154 results on '"Ocular biometrics"'
Search Results
2. Associations between corneal curvature and other anterior segment biometrics in young myopic adults
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Li Jiang, Zijing Du, Wei Sun, Shanqing Zhu, Lu Xiong, Xuejun Fang, Jin Zhou, Qingsong Zhang, Xiaohua Lei, Qingyan Zeng, Zheng Wang, and Yijun Hu
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Ocular biometrics ,Anterior segment biometrics ,Corneal biometrics ,Corneal curvature (CC) ,Myopia ,Refractive surgery ,Medicine ,Science - Abstract
Abstract To investigate the associations between corneal curvature (CC) and other anterior segment biometrics in young myopic adults. In this retrospective multi-center study, 7893 young myopic adults were included. CC and other anterior segment biometrics were measured by Scheimpflug imaging (Pentacam). CC was defined as SimK at central 3 mm area, and other anterior segment biometrics included white-to-white corneal diameter (WTW), central corneal thickness (CCT), corneal volume (CV) at 3 mm, 5 mm, and 7 mm area, anterior corneal astigmatism (ACA), posterior corneal astigmatism (PCA), anterior corneal eccentricity (ACE) and asphericity (ACAP), posterior corneal eccentricity (PCE) and asphericity (PCAP), anterior chamber depth (ACD), and anterior chamber volume (ACV). Univariate regression analyses were used to assess the associations between CC and other anterior segment biometrics, and multivariate regression analyses were further performed to adjusted for age, gender and spherical equivalent. CC was higher in patients of female gender and higher myopia (all P
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- 2024
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3. Association between body stature with ocular biometrics and refraction among Chinese preschoolers
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Linling Li, Chimei Liao, Xiaojuan Zhang, Juan Lu, Yangfa Zeng, Min Fu, and Decai Wang
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Association ,Body stature ,Ocular biometrics ,Refraction ,Preschool children ,Ophthalmology ,RE1-994 - Abstract
Abstract Purpose To evaluate the association of body stature with ocular biometrics and refraction in preschool children. Methods A cross-sectional, school-based study was conducted in Shenzhen, China. Preschool children aged 3 to 6 from 10 randomly-selected kindergartens were recruited. Ocular biometric parameters, including axial length (AL), anterior chamber depth (ACD), vitreous chamber depth (VCD), corneal radius curvature (CR), axial length to corneal radius ratio (AL-to-CR ratio) and lens thickness (LT) were measured using non-contact partial-coherence laser interferometry. Cycloplegic refractions were obtained by a desktop autorefractor. Body height and weight were measured using standard procedures. The association between body stature and ocular biometrics were analyzed with univariable and multivariable regression model. Results A total of 373 preschoolers were included. AL, ACD, VCD, CR, and AL-to-CR ratio, were positively associated with height and weight (p
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- 2024
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4. Ocular biometrics in eyes with different white-to-white corneal diameter in young myopic adults
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Li Jiang, Zijing Du, Changting Tang, Shanqing Zhu, Lu Xiong, Xuejun Fang, Jin Zhou, Qingsong Zhang, Wei Sun, Qingyan Zeng, Xiaohua Lei, Zheng Wang, and Yijun Hu
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Ocular biometrics ,Corneal biometrics ,Refractive surgery ,White-to-white corneal diameter (WTW) ,Myopia ,Medicine ,Science - Abstract
Abstract The interactions between white-to-white corneal diameter (WTW) and other ocular biometrics are important for planning of refractive surgery and understanding of ocular structural changes in myopia, but such interactions are rarely investigated in young myopic adults. This is a retrospective study involving 7893 young myopic adults from five centers. WTW and other ocular biometrics were measured by Pentacam. The ocular biometrics included anterior corneal curvature (AK) and posterior corneal curvature (PK), central corneal thickness (CCT) and corneal volume (CV), anterior and corneal eccentricity and asphericity, anterior corneal astigmatism (ACA) and posterior corneal astigmatism, anterior chamber depth (ACD), and anterior chamber volume (ACV). The ocular biometrics were compared among eyes of different WTW quartiles. Multivariate linear regression was used to assess the linear associations between WTW and other ocular biometrics adjusting for age, gender and spherical equivalent. In eyes of different WTW quartiles, other ocular biometrics were also significantly different (all P
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- 2024
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5. Association Between Peripheral Retinal Defocus and Myopia by Multispectral Refraction Topography in Chinese Children
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Bao T, Qin L, Hou G, Jiang H, Wang L, Wang Y, Wu J, Wang J, and Pang Y
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peripheral refractive errors ,myopia ,spherical equivalent ,logistic analysis ,ocular biometrics ,Ophthalmology ,RE1-994 - Abstract
Tong Bao,1,* Liru Qin,2,* Guimei Hou,1 Hongmei Jiang,1 Lifeng Wang,1 Ying Wang,1 Junhui Wu,1 Jinli Wang,3 Yunlei Pang4 1Department of Ophthalmological Examination, Chifeng Chaoju Eye Hospital, Chifeng, People’s Republic of China; 2Department of Ophthalmology, Inner Mongolia Baogang Hospital, Baotou, People’s Republic of China; 3Department of Cataract, Chifeng Chaoju Eye Hospital, Chifeng, People’s Republic of China; 4Department of Ophthalmic Plastic Surgery, Chifeng Chaoju Eye Hospital, Chifeng, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jinli Wang, Department of Cataract, Chifeng Chaoju Eye Hospital, Chifeng, People’s Republic of China, Email chaojueyewjl66@163.com Yunlei Pang, Department of Ophthalmic Plastic Surgery, Chifeng Chaoju Eye Hospital, Chifeng, People’s Republic of China, Email 29483645@qq.comObjective: To investigate the association between the peripheral refractive errors of the fundus in different regions and moderate and high myopia.Methods: In this case-control study, 320 children and adolescents aged 6 to 18 years were recruited. Peripheral refractive errors were measured using multispectral retinal refractive topography (MRT). Spherical equivalent (SE) and cylinder errors were classified into low, moderate, and high categories based on the magnitude range. Logistic regression was performed to test the factors associated with myopia.Results: There were 152 participants with low myopia and 168 participants with moderate and high myopia included in the current study. Participants with moderate and high myopia were most likely to be older, with larger axial length (AL), lower SE, less time to watch electronic devices on the weekend, a higher difference between central refractive error and paracentral refractive error from the superior side of the retina (RDV-S), but a smaller difference between the central refractive error and paracentral refractive error from the inferior side of the retina (RDV-I) than those with low myopia (all P < 0.05). After logistic analysis, female sex (odds ratio [OR] = 4.14; 95% confidence interval [CI] = 2.16– 7.97, P < 0.001), AL (OR = 6.88, 95% CI = 4.33– 10.93, P < 0.001), and RDV-I (OR = 0.52, 95% CI = 0.32– 0.86, P = 0.010) were independent factors for moderate and high myopia.Conclusion: Our study demonstrated that the retina peripheral refraction of the eyes (RDV-I) was associated with moderate and high myopia, and RDV-S was only associated with high myopia.Keywords: peripheral refractive errors, myopia, spherical equivalent, logistic analysis, ocular biometrics
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- 2024
6. Associations between corneal curvature and other anterior segment biometrics in young myopic adults.
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Jiang, Li, Du, Zijing, Sun, Wei, Zhu, Shanqing, Xiong, Lu, Fang, Xuejun, Zhou, Jin, Zhang, Qingsong, Lei, Xiaohua, Zeng, Qingyan, Wang, Zheng, and Hu, Yijun
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CORNEA , *BIOMETRY , *CURVATURE , *REGRESSION analysis , *MULTIVARIATE analysis - Abstract
To investigate the associations between corneal curvature (CC) and other anterior segment biometrics in young myopic adults. In this retrospective multi-center study, 7893 young myopic adults were included. CC and other anterior segment biometrics were measured by Scheimpflug imaging (Pentacam). CC was defined as SimK at central 3 mm area, and other anterior segment biometrics included white-to-white corneal diameter (WTW), central corneal thickness (CCT), corneal volume (CV) at 3 mm, 5 mm, and 7 mm area, anterior corneal astigmatism (ACA), posterior corneal astigmatism (PCA), anterior corneal eccentricity (ACE) and asphericity (ACAP), posterior corneal eccentricity (PCE) and asphericity (PCAP), anterior chamber depth (ACD), and anterior chamber volume (ACV). Univariate regression analyses were used to assess the associations between CC and other anterior segment biometrics, and multivariate regression analyses were further performed to adjusted for age, gender and spherical equivalent. CC was higher in patients of female gender and higher myopia (all P < 0.05). Eyes in higher CC quartiles had lower WTW, thinner CCT, lower CV at 3 mm and 5 mm, lower ACD, and lower ACV (all P < 0.001), but had larger ACA, larger PCA, less PCE and less PCAP (all P < 0.001), compared to eyes in lower CC quartiles. The trends of CV at 7 mm, ACE and ACAP were inconsistent in different CC quartiles. After adjusting for age, gender and spherical equivalent with multivariate linear regression, CC was positively correlated to CV at 7 mm (βs = 0.069), ACA (βs = 0.194), PCA (βs = 0.187), ACE (βs = 0.072), PCAP (βs = 0.087), and ACD (βs = 0.027) (all P < 0.05), but was negatively correlated to WTW (βs = − 0.432), CCT (βs = − 0.087), CV-3 mm (βs = − 0.066), ACAP (βs = − 0.043), PCE (βs = − 0.062), and ACV (βs = − 0.188) (all P < 0.05). CC was associated with most of the other anterior segment biometrics in young myopic adults. These associations are important for better understanding of the interactions between different anterior segment structures in young myopic patients, and are also useful for the exploration of the pathogenesis of myopia. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Association between body stature with ocular biometrics and refraction among Chinese preschoolers.
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Li, Linling, Liao, Chimei, Zhang, Xiaojuan, Lu, Juan, Zeng, Yangfa, Fu, Min, and Wang, Decai
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VISUAL accommodation ,STATURE ,PRESCHOOL children ,LASER interferometry ,BODY weight - Abstract
Purpose: To evaluate the association of body stature with ocular biometrics and refraction in preschool children. Methods: A cross-sectional, school-based study was conducted in Shenzhen, China. Preschool children aged 3 to 6 from 10 randomly-selected kindergartens were recruited. Ocular biometric parameters, including axial length (AL), anterior chamber depth (ACD), vitreous chamber depth (VCD), corneal radius curvature (CR), axial length to corneal radius ratio (AL-to-CR ratio) and lens thickness (LT) were measured using non-contact partial-coherence laser interferometry. Cycloplegic refractions were obtained by a desktop autorefractor. Body height and weight were measured using standard procedures. The association between body stature and ocular biometrics were analyzed with univariable and multivariable regression model. Results: A total of 373 preschoolers were included. AL, ACD, VCD, CR, and AL-to-CR ratio, were positively associated with height and weight (p < 0.05), whereas LT was negatively associated with height and weight (p < 0.01). No association was observed between stature and central cornea thickness and refraction. After adjusted for age and gender in a multivariable regression model, AL had positive associations with height (p < 0.01) and weight (p < 0.01). However, refraction had no significant association with stature parameters. Conclusion: Taller and heavier preschoolers had eyes with longer AL, deeper vitreous chamber, and flatter cornea. The significant associations between body stature and ocular biometric parameters reveal the driving influence of body development on the growth of eyeballs in preschoolers. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Ocular biometrics in eyes with different white-to-white corneal diameter in young myopic adults.
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Jiang, Li, Du, Zijing, Tang, Changting, Zhu, Shanqing, Xiong, Lu, Fang, Xuejun, Zhou, Jin, Zhang, Qingsong, Sun, Wei, Zeng, Qingyan, Lei, Xiaohua, Wang, Zheng, and Hu, Yijun
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CORNEA , *BIOMETRY , *DIAMETER , *OPTIC disc , *ASTIGMATISM - Abstract
The interactions between white-to-white corneal diameter (WTW) and other ocular biometrics are important for planning of refractive surgery and understanding of ocular structural changes in myopia, but such interactions are rarely investigated in young myopic adults. This is a retrospective study involving 7893 young myopic adults from five centers. WTW and other ocular biometrics were measured by Pentacam. The ocular biometrics included anterior corneal curvature (AK) and posterior corneal curvature (PK), central corneal thickness (CCT) and corneal volume (CV), anterior and corneal eccentricity and asphericity, anterior corneal astigmatism (ACA) and posterior corneal astigmatism, anterior chamber depth (ACD), and anterior chamber volume (ACV). The ocular biometrics were compared among eyes of different WTW quartiles. Multivariate linear regression was used to assess the linear associations between WTW and other ocular biometrics adjusting for age, gender and spherical equivalent. In eyes of different WTW quartiles, other ocular biometrics were also significantly different (all P < 0.05). After adjusting for age, gender and spherical equivalent, WTW was positively correlated to AK (β = 0.26 to 0.29), ACA (β = 0.13), anterior corneal asphericity (β = 0.05), PK (β = 0.33 to 0.34), posterior corneal asphericity (β = 0.13), ACD (β = 0.29), and ACV (β = 40.69), and was negatively correlated to CCT (β = − 6.83), CV (β = − 0.06 to − 0.78), anterior corneal eccentricity (β = − 0.035), and posterior corneal eccentricity (β = − 0.14) (all P < 0.001). In conclusion, we found that in young myopic adults, larger WTW was associated with thinner corneal thickness, flatter corneal curvature, more anterior corneal toricity, less corneal eccentricity and asphericity, and broader anterior chamber. Our findings may fill in the gap of literature, and help us better understand how the anterior segment structures interact with the WTW in myopia. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Analysis of Multimodal Biometric System Based on ECG Biometrics
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Singh, Sandeep Pratap, Tiwari, Shamik, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Jain, Raj, editor, Travieso, Carlos M., editor, and Kumar, Sanjeev, editor
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- 2023
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10. IPAD: Iterative pruning with activation deviation for sclera biometrics
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Matej Vitek, Matic Bizjak, Peter Peer, and Vitomir Štruc
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Biometrics ,Sclera segmentation ,Ocular biometrics ,Ocular segmentation ,Model pruning ,Lightweight deep learning ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
The sclera has recently been gaining attention as a biometric modality due to its various desirable characteristics. A key step in any type of ocular biometric recognition, including sclera recognition, is the segmentation of the relevant part(s) of the eye. However, the high computational complexity of the (deep) segmentation models used in this task can limit their applicability on resource-constrained devices such as smartphones or head-mounted displays. As these devices are a common desired target for such biometric systems, lightweight solutions for ocular segmentation are critically needed. To address this issue, this paper introduces IPAD (Iterative Pruning with Activation Deviation), a novel method for developing lightweight convolutional networks, that is based on model pruning. IPAD uses a novel filter-activation-based criterion (ADC) to determine low-importance filters and employs an iterative model pruning procedure to derive the final lightweight model. To evaluate the proposed pruning procedure, we conduct extensive experiments with two diverse segmentation models, over four publicly available datasets (SBVPI, SLD, SMD and MOBIUS), in four distinct problem configurations and in comparison to state-of-the-art methods from the literature. The results of the experiments show that the proposed filter-importance criterion outperforms the standard L1 and L2 approaches from the literature. Furthermore, the results also suggest that: (i) the pruned models are able to retain (or even improve on) the performance of the unpruned originals, as long as they are not over-pruned, with RITnet and U-Net at 50% of their original FLOPs reaching up to 4% and 7% higher IoU values than their unpruned versions, respectively, (ii) smaller models require more careful pruning, as the pruning process can hurt the model’s generalization capabilities, and (iii) the novel criterion most convincingly outperforms the classic approaches when sufficient training data is available, implying that the abundance of data leads to more robust activation-based importance computation.
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- 2023
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11. Benchmarking Neural Network Compression Techniques for Ocular-Based User Authentication on Smartphones
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Ali Almadan and Ajita Rattani
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On-device AI ,edge computing ,ocular biometrics ,mobile biometrics ,neural network compression ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
With the unprecedented mobile technology revolution, mobile devices have transcended from being the primary means of communication to an all-in-one platform. Consequently, an increasing number of individuals are accessing online services for e-commerce and banking via smartphones instead of traditional desktop computers. However, smartphones can be easily misplaced, lost, or stolen more often than other computing devices, thereby demanding effective user authentication mechanisms for device unlocking and secured transactions. Ocular biometrics has obtained significant attention from academia and industry because of its accuracy, security, and ease of use in mobile devices. Several studies have demonstrated the efficacy of deep learning models for ocular-based user authentication on smartphones. However, these high-performing models require enormous space and computational complexity due to the millions of parameters and computations involved. These requirements make their deployment on resource-constrained smartphones challenging. To this end, a handful of studies have been proposed for compact-size ocular-based deep-learning models to facilitate on-device deployment. In this paper, we conduct a thorough analysis of the existing neural network compression techniques applied as a standalone and in combination for ocular-based user authentication. Extensive experimental validation is performed on the two latest large-scale ocular biometric datasets collected using smartphones, namely, UFPR and VISOB 2.0 datasets. This study benchmarks the results of advanced compression techniques for further research and development in lightweight models for ocular-based user authentication on smartphones.
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- 2023
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12. Low-Dose Atropine Induces Changes in Ocular Biometrics in Myopic Children: Exploring Temporal Changes by Linear Mixed Models and Contribution to Treatment Effect by Mediation Analyses.
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Hvid-Hansen, Anders, Jacobsen, Nina, Hjortdal, Jesper, Møller, Flemming, Ozenne, Brice, and Kessel, Line
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ATROPINE , *TREATMENT effectiveness , *CHOROID , *BIOMETRY , *CONFIDENCE intervals - Abstract
This study aimed to investigate changes in non-cycloplegic ocular biometrics during the initial six months of treatment with a 0.1% atropine loading dose and 0.01% atropine compared with a placebo and analyze their contribution to the treatment effect on cycloplegic spherical equivalent (SE) progression. The study was based on a randomized, double-masked, placebo-controlled, multicenter trial evaluating a 0.1% atropine six-month loading dose and 0.01% atropine in reducing myopic progression in Danish children. The treatment phase was 24 months, and the washout phase was 12 months. Parameters measured included changes in axial length (AL), anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and choroidal thickness (ChT), while cycloplegic SE and lens power were calculated. Longitudinal changes and contributions to treatment effects were analyzed using constrained linear mixed models and mediation analyses, respectively. After six months, AL was 0.13 mm shorter (95% confidence interval [CI], −0.18 to −0.07 [adjusted p < 0.001]) and 0.06 mm shorter (95% CI, −0.11 to −0.01 [adjusted p = 0.060]) with a 0.1% atropine loading dose and 0.01% atropine, respectively, compared to the placebo group. Similar concentration-dependent changes were found with ACD, LT, VCD, ChT, and cycloplegic SE. Although the treatment effects trended toward concentration-dependent responses, only the treatment effect mediated by AL at three months differed significantly between 0.01% atropine and a 0.1% atropine loading dose (adjusted p = 0.023). Several ocular biometrics, including AL, ACD, and LT, changed dose-dependently during low-dose atropine treatment. Moreover, the treatment effect of atropine on SE progression was mediated by a subset of ocular biometrics, mainly AL, with trends toward concentration dependency and distributional shifts over time. [ABSTRACT FROM AUTHOR]
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- 2023
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13. The distribution pattern of corneal volume in Chinese myopic patients from multiple centers
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Changting Tang, Linyuan Qin, Wei Wang, Suqing Lu, Yinan Li, Ying Fang, Honghua Yu, and Yijun Hu
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corneal biometrics ,corneal volume (CV) ,myopia ,ocular biometrics ,refractive surgery ,Medical technology ,R855-855.5 ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
Abstract Corneal volume (CV) is a useful index for detecting forme fruste keratoconus from normal corneas. It can be used to evaluate the whole cornea, since it can measure corneal areas up to 10 mm in diameter. Thus, CV has become the clinicians' interest as a diagnostic tool of corneal ectatic disease and a measure of corneal integrity to determine suitability for refractive surgery. We conducted a cross‐sectional study including 7893 myopic patients from five ophthalmic centers to investigate the distribution pattern of CV. Our study showed that distribution of CV‐3, CV‐5, and CV‐7 mm were slightly positively skewed and the 2.5th to 97.5th percentiles were 3.6–4.4, 10.4–12.8, 22.5–27.5 mm3, respectively. Central corneal thickness (CCT) was significantly correlated with CV in all measurement regions. The correlation between CV and CCT showed an inconsistent trend with the increase of age. The correlation coefficient between CV and CCT did not change significantly with the increase of myopia degree in low to moderate myopia, but fluctuated significantly in high myopia (less than −6.0 diopters). According to our results, corneal volume follows a slightly positively skewed distribution pattern in myopic Chinese patients. The information is useful for screening refractive surgery candidates and assessing the risk of corneal refractive surgery.
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- 2023
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14. High prevalence of myopia and low hyperopia reserve in 4411 Chinese primary school students and associated risk factors
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Yu Yue, Xianmao Liu, Shu Yi, Bo Liu, Hong Yi, and Hong Li
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Myopia ,Prevalence ,Ocular biometrics ,Risk factors ,Ophthalmology ,RE1-994 - Abstract
Abstract Purpose To investigate the prevalence of myopia in Chinese primary school students and their ocular biometrics including axial length (AL), corneal radius of curvature (CRC) and spherical equivalent refraction (SER). To analyze their association with potential myopia risk factors, such as body mass index (BMI), cram school, time of outdoor activity and electronic screen use. Methods In this cross-sectional study of 4500 primary school students from 5 schools, participants underwent refraction using non-cycloplegic autorefractor and visual acuity testing. A follow-up study in the same schools was conducted in 2022. Myopia was defined as SER ≤ -0.50 diopter (D) and uncorrected visual acuity (UCVA)
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- 2022
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15. Accuracy of new-generation intraocular lens calculation formulas in eyes with variations in predicted refraction.
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Chang, Pingjun, Qian, Shuyi, Wang, Yalan, Li, Siyan, Yang, Fuman, Hu, Yiwen, Liu, Zhuohan, and Zhao, Yun-e
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INTRAOCULAR lenses , *PHOTOREFRACTIVE keratectomy , *CATARACT surgery , *VISUAL accommodation , *CORNEA - Abstract
Purpose: To investigate the characteristics of eyes with large variations in predicted refraction using four traditional intraocular lens (IOL) formulas and evaluate the accuracy of new-generation intraocular lens power calculation formulas. Methods: Eyes that had variation in predicted refraction (≥ 0.75 D) using four traditional formulas (SRK/T, Holladay 1, Hoffer Q, and Haigis formulas) were included. Axial length (AL), anterior chamber depth (ACD), average keratometry (AK), and the ratio of axial length to corneal radius (AL/CR) were measured. New-generation formulas (Barrett Universal II, Emmetropia Verifying Optical 2.0, Kane, and Pearl-DGS formulas) and traditional formulas were compared. The median absolute error (MedAE) was the main parameter to evaluate the accuracy of formulas. Results: A total of 79 participants (79 eyes) who had variation in predicted refraction of (≥ 0.75 D) using four traditional formulas out of 510 eyes (510 patients) underwent uncomplicated cataract surgeries. The Barrett Universal II (0.29 D), EVO 2.0 (0.31 D), Kane (0.30 D), and Pearl-DGS (0.33 D) formulas produced significantly lower median absolute errors (MedAEs) than the Hoffer Q (0.61 D) and Holladay 1 (0.59 D) formulas (P < 0.01). The Wang-Koch (WK) adjustment significantly improved the accuracy of the Holladay 1 formula in long eyes (P < 0.001). Conclusions: Abnormal AL, ACD, and AK are more likely to lead to prediction errors using traditional formulas. New-generation formulas and traditional formulas with WK adjustment showed satisfactory prediction accuracy. [ABSTRACT FROM AUTHOR]
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- 2023
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16. Effect of 0.02% and 0.01% atropine on ocular biometrics: A two-year clinical trial
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Ming Wang, Can Cui, Shi-Ao Yu, Ling-ling Liang, Jing-Xue Ma, and Ai-Cun Fu
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myopia ,children ,efficacy ,ocular biometrics ,low-concentration atropine ,Pediatrics ,RJ1-570 - Abstract
BackgroundSeveral studies have shown that various concentrations of low-concentration atropine can reduce myopia progression and control axial elongation safely and efficiently in children. The aim of this study was to evaluate the effects of 0.02% and 0.01% atropine on ocular biometrics.MethodsCohort study. 138 and 142 children were randomized to use either 0.02% or 0.01% atropine eye drops, respectively. They wore single-vision (SV) spectacles, with one drop of atropine applied to both eyes nightly. Controls (N = 120) wore only SV spectacles. Ocular and corneal astigmatism were calculated using Thibos vector analysis and split into J0 and J45.ResultsThe changes in cycloplegic spherical equivalent refraction (SER) and axial length (AL) were −0.81 ± 0.52D, −0.94 ± 0.59D, and −1.33 ± 0.72D; and 0.62 ± 0.29 mm, 0.72 ± 0.31 mm, and 0.89 ± 0.35 mm in the 0.02% and 0.01% atropine and control groups, respectively (all P 0.05). Intraocular pressure (IOP), corneal curvature, ocular astigmatism J45, and corneal astigmatism (including J0 and J45) remained stable over time in the three groups (all P > 0.05). The contributions to SER progression from the changes in AL, lens and corneal power of the three groups were similar (P > 0.05). The contribution of AL change alone to the change in SER was 56.3%, 63.4% and 78.2% in the above corresponding three groups.ConclusionsAfter 2 years, 0.02% and 0.01% atropine had no clinical effects on corneal and lens power, ocular and corneal astigmatism, ACD or IOP compared to the control group. 0.02% and 0.01% atropine helped to control myopia progression mainly by reducing AL elongation.
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- 2023
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17. Changes in Ocular Biometric Parameters Over a 24-Hour Period in Ocular Hypertensive Patients.
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Fan, Shan, Gulati, Vikas, Neely, Donna G., Andersen, Austin, and Toris, Carol B.
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Purpose: To identify 24-h changes in ocular biometric parameters in subjects with ocular hypertension (OHT), and to determine if an intraocular pressure (IOP)-lowering drug alters these parameters. Methods: Thirty volunteers with OHT (58.6 ± 9.2 years of age) were enrolled in this randomized, double-masked, placebo-controlled, crossover study. Participants self-administered 0.2% brimonidine or placebo 3 times daily for 6 weeks. Measurements of seated and supine IOP, central cornea thickness (CCT), anterior chamber depth (ACD), axial length (AXL), and lens thickness were made at 8 am, 3 pm, 8 pm, and 3 am. Statistical tests were Student's 2-tailed paired t-tests or 2-way analysis of variance (ANOVA) followed by one-way ANOVA and post hoc testing. Results: Time of day had a significant effect on IOP, CCT, ACD, and AXL. In placebo-treated eyes, CCT was greater at 3 am than at any other time (P < 0.01), ACD and AXL were greater at 3 am and 8 pm than at 3 pm (P < 0.01). Daytime IOPs were higher than nighttime (seated, P = 0.007; supine, P = 0.018), and supine IOP at night was higher than seated IOP during the day (P < 0.001). Brimonidine did not lower IOP at night nor did it alter the 24-h patterns of CCT, ACD, and AXL. Conclusions: Ocular biometric parameters exhibit characteristic 24-h fluctuations in patients with OHT. At night compared with day, the supine IOP increases, the cornea thickens, the anterior chamber deepens, and the AXL increases. Brimonidine does not alter these parameters at times when it lowers IOP (day) nor when it does not (night). Clinical Trial Registration number: NCT0132419. [ABSTRACT FROM AUTHOR]
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- 2022
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18. Deep Sclera Segmentation and Recognition
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Rot, Peter, Vitek, Matej, Grm, Klemen, Emeršič, Žiga, Peer, Peter, Štruc, Vitomir, Kang, Sing Bing, Series Editor, Singh, Sameer, Founding Editor, Bischof, Horst, Advisory Editor, Bowden, Richard, Advisory Editor, Dickinson, Sven, Advisory Editor, Jia, Jiaya, Advisory Editor, Lee, Kyoung Mu, Advisory Editor, Sato, Yoichi, Advisory Editor, Schiele, Bernt, Advisory Editor, Sclaroff, Stan, Advisory Editor, Uhl, Andreas, editor, Busch, Christoph, editor, Marcel, Sébastien, editor, and Veldhuis, Raymond, editor
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- 2020
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19. Cross-sensor periocular biometrics in a global pandemic: Comparative benchmark and novel multialgorithmic approach.
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Alonso-Fernandez, Fernando, Raja, Kiran B., Raghavendra, R., Busch, Christoph, Bigun, Josef, Vera-Rodriguez, Ruben, and Fierrez, Julian
- Subjects
- *
BIOMETRY , *SUPPORT vector machines , *LOGISTIC regression analysis , *SPECTRAL imaging , *COVID-19 , *SYSTEM integration , *IMAGE registration , *HUMAN facial recognition software - Abstract
The massive availability of cameras and personal devices results in a wide variability between imaging conditions, producing large intra-class variations and a significant performance drop if images from heterogeneous environments are compared for person recognition purposes. However, as biometric solutions are extensively deployed, it will be common to replace acquisition hardware as it is damaged or newer designs appear or to exchange information between agencies or applications operating in different environments. Furthermore, variations in imaging spectral bands can also occur. For example, face images are typically acquired in the visible (VIS) spectrum, while iris images are usually captured in the near-infrared (NIR) spectrum. However, cross-spectrum comparison may be needed if, for example, a face image obtained from a surveillance camera needs to be compared against a legacy database of iris imagery. Here, we propose a multialgorithmic approach to cope with periocular images captured with different sensors. With face masks in the front line to fight against the COVID-19 pandemic, periocular recognition is regaining popularity since it is the only region of the face that remains visible. As a solution to the mentioned cross-sensor issues, we integrate different biometric comparators using a score fusion scheme based on linear logistic regression This approach is trained to improve the discriminating ability and, at the same time, to encourage that fused scores are represented by log-likelihood ratios. This allows easy interpretation of output scores and the use of Bayes thresholds for optimal decision-making since scores from different comparators are in the same probabilistic range. We evaluate our approach in the context of the 1st Cross-Spectral Iris/Periocular Competition, whose aim was to compare person recognition approaches when periocular data from visible and near-infrared images is matched. The proposed fusion approach achieves reductions in the error rates of up to 30%–40% in cross-spectral NIR–VIS comparisons with respect to the best individual system, leading to an EER of 0.2% and a FRR of just 0.47% at FAR = 0.01%. It also represents the best overall approach of the mentioned competition. Experiments are also reported with a database of VIS images from two different smartphones as well, achieving even bigger relative improvements and similar performance numbers. We also discuss the proposed approach from the point of view of template size and computation times, with the most computationally heavy comparator playing an important role in the results. Lastly, the proposed method is shown to outperform other popular fusion approaches in multibiometrics, such as the average of scores, Support Vector Machines, or Random Forest. • Multialgorithmic approach for periocular recognition using images from different sensors. • Integration of systems at the score level using linear logistic regression fusion. • Evaluation in both visible-to-visible and visible-to-near-infrared comparisons. • Comparison with popular fusion approaches employed in multibiometrics. • Best overall approach evaluated in cross-eyed periocular competitions. [ABSTRACT FROM AUTHOR]
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- 2022
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20. High prevalence of myopia and low hyperopia reserve in 4411 Chinese primary school students and associated risk factors.
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Yue, Yu, Liu, Xianmao, Yi, Shu, Liu, Bo, Yi, Hong, and Li, Hong
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SCHOOL children ,MYOPIA ,HYPEROPIA ,AT-risk students ,MEDICAL personnel ,BODY mass index ,VISUAL acuity - Abstract
Purpose: To investigate the prevalence of myopia in Chinese primary school students and their ocular biometrics including axial length (AL), corneal radius of curvature (CRC) and spherical equivalent refraction (SER). To analyze their association with potential myopia risk factors, such as body mass index (BMI), cram school, time of outdoor activity and electronic screen use.Methods: In this cross-sectional study of 4500 primary school students from 5 schools, participants underwent refraction using non-cycloplegic autorefractor and visual acuity testing. A follow-up study in the same schools was conducted in 2022. Myopia was defined as SER ≤ -0.50 diopter (D) and uncorrected visual acuity (UCVA) < 0.00 logMAR (6/6). Logistic regression models were used to determine factors associated with myopia.Results: After excluding 389 participants, the overall prevalence of myopia was 33.6%. The prevalence of high myopia was 0.6%. The prevalence of myopia in girls was significantly higher than that in boys (37.6% vs. 30.0%, p < 0.001). The height, weight and BMI were significantly associated with AL (r = 0.471, r = 0.440, r = 0.276, p < 0.001, respectively). AL/CRC ratio was more highly correlated with SER than AL alone. Regression analysis showed that AL/CRC and hyperopia reserve were associated with myopia onset in the subsequent year (F = 201.557, p < 0.001; F = 68.934, p < 0.001). The cut point of hyperopia reserve for myopia in the subsequent year for grade 1 students was + 0.31D. Age (p < 0.001), parental myopia (p = 0.001) and lack of outdoor activity between classes (p = 0.049) were independently associated with higher prevalence rates of myopia.Conclusion: The prevalence of myopia among Chinese schoolchildren is alarming high. Consistent with previous cross-sectional data, AL/CRC and hyperopia reserve could function as myopia detection indicators. The hyperopia reserve among children aged between 6 ~ 7 years was low. Healthcare providers need to raise parents' awareness of the importance of regular eye examination and proper optical correction. [ABSTRACT FROM AUTHOR]- Published
- 2022
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21. Unraveling effects of ocular features on the performance of periocular biometrics.
- Author
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Kumar, Gautam, Bakshi, Sambit, Khan, Muhammad Attique, and Albarakati, Hussain Mobarak
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- *
BIOMETRIC identification , *INTERNETWORKING , *CONTACT lenses , *DISTRIBUTION (Probability theory) , *IRIS recognition - Abstract
Periocular recognition has grown in popularity in biometrics applications over the years, and it is now being used in several large-scale national initiatives. Even though periocular patterns are unique, extrinsic factors like illumination, disease in the eye, camera-eye angle, and sensor interoperability can influence them. The use of contact lenses, particularly color cosmetic lenses, can complicate ocular biometrics by obscuring feature patterns and altering inter-class and intra-class distributions. This paper presents an in-depth analysis of changes in the eye (iris and sclera) color on periocular recognition performance. For this purpose, the proposed method generates an augmented dataset by masking out the ocular region (sclera and iris area) from a subject's periocular images and replacing it with other subjects' ocular regions. We simulate the uses of colored contact lenses by performing three experiments, and for each experiment, three cases are considered (recognition using the left eye, right eye, and both eyes). Statistical parameters are measured and compared to evaluate the performance, reliability, flexibility, robustness, and usability of periocular biometrics under different scenarios. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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22. Ocular Biometric Risk Factors for Progression of Primary Angle Closure Disease: The Zhongshan Angle Closure Prevention Trial.
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Xu, Benjamin Y., Friedman, David S., Foster, Paul J., Jiang, Yu, Porporato, Natalia, Pardeshi, Anmol A., Jiang, Yuzhen, Munoz, Beatriz, Aung, Tin, and He, Mingguang
- Subjects
- *
ANGLE-closure glaucoma , *RECEIVER operating characteristic curves , *GLAUCOMA , *BIOMETRY , *INTRAOCULAR pressure - Abstract
To assess baseline ocular biometric risk factors for progression from primary angle closure suspect (PACS) to primary angle closure (PAC) or acute angle closure (AAC). Prospective, observational study. Six hundred forty-three mainland Chinese with untreated PACS. Participants underwent baseline clinical examinations, including gonioscopy, anterior segment OCT (AS-OCT) imaging, and A-scan ultrasound biometry as part of the Zhongshan Angle Closure Prevention (ZAP) Trial. Primary angle closure suspect was defined as an inability to visualize pigmented trabecular meshwork in 2 or more quadrants based on static gonioscopy. Primary angle closure was defined as development of intraocular pressure above 24 mmHg or peripheral anterior synechiae. Progression was defined as development of PAC or an AAC attack. Multivariable logistic regression models were developed to assess biometric risk factors for progression. Six-year progression from PACS to PAC or AAC. Six hundred forty-three untreated eyes (609 nonprogressors, 34 progressors) of 643 participants were analyzed. In a multivariable model with continuous parameters, narrower horizontal angle opening distance of 500 μm from the scleral spur (AOD 500 ; odds ratio [OR], 1.10 per 0.01-mm decrease; P = 0.03), flatter horizontal iris curvature (IC; OR, 1.96 per 0.1-mm decrease; P = 0.01), and older age (OR, 1.11 per 1-year increase; P = 0.01) at baseline were associated significantly with progression (area under the receiver operating characteristic curve [AUC], 0.73). Smaller cumulative gonioscopy score was not associated with progression (OR, 1.03 per 1-modified Shaffer grade decrease; P = 0.85) when replacing horizontal AOD 500 in the multivariable model. In a separate multivariable model with categorical parameters, participants in the lowest quartile of horizontal AOD 500 (OR, 3.10; P = 0.002) and IC (OR, 2.48; P = 0.014) measurements and 59 years of age or older (OR, 2.68; P = 0.01) at baseline showed higher odds of progression (AUC, 0.72). Ocular biometric measurements can help to risk-stratify patients with early angle closure for more severe disease. Anterior segment OCT measurements of biometric parameters describing the angle and iris are predictive of progression from PACS to PAC or AAC, whereas gonioscopy grades are not. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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23. Ocular recognition databases and competitions: a survey.
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Zanlorensi, Luiz A., Laroca, Rayson, Luz, Eduardo, Britto Jr., Alceu S., Oliveira, Luiz S., and Menotti, David
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DEEP learning ,CONTACT lenses ,DATABASES ,CONTESTS ,IRIS recognition ,DRUG utilization - Abstract
The use of the iris and periocular region as biometric traits has been extensively investigated, mainly due to the singularity of the iris features and the use of the periocular region when the image resolution is not sufficient to extract iris information. In addition to providing information about an individual's identity, features extracted from these traits can also be explored to obtain other information such as the individual's gender, the influence of drug use, the use of contact lenses, spoofing, among others. This work presents a survey of the databases created for ocular recognition, detailing their protocols and how their images were acquired. We also describe and discuss the most popular ocular recognition competitions (contests), highlighting the submitted algorithms that achieved the best results using only iris trait and also fusing iris and periocular region information. Finally, we describe some relevant works applying deep learning techniques to ocular recognition and point out new challenges and future directions. Considering that there are a large number of ocular databases, and each one is usually designed for a specific problem, we believe this survey can provide a broad overview of the challenges in ocular biometrics. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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24. Research progress in clinical application of a swept-source optical coherence tomography biometer OA-2000
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Bo Liu, Xuan Liao, and Chang-Jun Lan
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oa-2000 ,ocular biometrics ,clinical application ,optical low coherent reflectometry ,repeatability ,consistency ,Ophthalmology ,RE1-994 - Abstract
With the advances in cataract phacoemulsification and intraocular lens implantation, more and more attention has been paid to the postoperative effects by both clinicians and patients. Meanwhile, the instruments for the preoperative measurements are also evolving. Various types of ocular biometers have emerged, which have evolved the principles from ultrasound to swept-source optical coherence tomography(SS-OCT). The OA-2000, a new type of SS-OCT based ocular biometer with fully automatic three-dimensional scanning, has the advantages of simple and safe operation, high resolution, excellent repeatability, fast measurement and good tissue penetration. It can obtain multiple ocular biological parameters in one measurement, which enables a wide application prospect. Here, we review the measurement principle and clinical application of OA-2000.
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- 2020
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25. Relationship Between Peripheral Refraction in Different Retinal Regions and Myopia Development of Young Chinese People
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Xiangyue Zheng, Dejin Cheng, Xiaoli Lu, Xiaoyi Yu, Yuting Huang, Yujie Xia, Chuni Lin, and Zhao Wang
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peripheral refraction ,myopia ,multispectral refractive topography ,ocular biometrics ,retinal eccentricity ,Medicine (General) ,R5-920 - Abstract
ObjectiveTo observe the associations between regional peripheral refraction and myopia development in young Chinese people.MethodsTwo hundred and forty-one young adult subjects (21 emmetropes, 88 low myopes, 94 moderate myopes, and 38 high myopes) aged 18–28 years were included, and only the right eyes were tested. Eye biometrics were measured before pupil dilation using the Lenstar. Relative peripheral refractive errors (RPRE) were measured after pupil dilation using multispectral refractive topography (MRT), at nine retinal eccentricities: 0–5, 5–10, 10–15, 15–20, 20–25, 25–30, 30–35, 35–40, and 40–45 degrees.ResultsIn this study, RPRE increased with eccentricity, and it shows a growing trend with the increase of the degree of myopia among emmetropia, low myopia and moderate myopia groups, and RPRE varied with myopia severity at eccentricities between 20 and 35 degrees only. In addition, axial length (AL) and RPRE were positively correlated between 20 and 45 degrees, and AL was an independent risk factor for RPRE between 20 and 35 degrees.ConclusionThese findings indicate that the eccentricities between 20 and 35 degrees RPRE may be closely related to refractive development and eye growth in young Chinese people.
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- 2022
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26. A comprehensive investigation into sclera biometrics: a novel dataset and performance study.
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Vitek, Matej, Rot, Peter, Štruc, Vitomir, and Peer, Peter
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- *
SCLERA , *BIOMETRY , *EYELASHES , *PERFORMANCE theory , *IRIS recognition , *VISIBLE spectra , *BLOOD vessels - Abstract
The area of ocular biometrics is among the most popular branches of biometric recognition technology. This area has long been dominated by iris recognition research, while other ocular modalities such as the periocular region or the vasculature of the sclera have received significantly less attention in the literature. Consequently, ocular modalities beyond the iris are not well studied and their characteristics are today still not as well understood. While recent needs for more secure authentication schemes have considerably increased the interest in competing ocular modalities, progress in these areas is still held back by the lack of publicly available datasets that would allow for more targeted research into specific ocular characteristics next to the iris. In this paper, we aim to bridge this gap for the case of sclera biometrics and introduce a novel dataset designed for research into ocular biometrics and most importantly for research into the vasculature of the sclera. Our dataset, called Sclera Blood Vessels, Periocular and Iris (SBVPI), is, to the best of our knowledge, the first publicly available dataset designed specifically with research in sclera biometrics in mind. The dataset contains high-quality RGB ocular images, captured in the visible spectrum, belonging to 55 subjects. Unlike competing datasets, it comes with manual markups of various eye regions, such as the iris, pupil, canthus or eyelashes and a detailed pixel-wise annotation of the complete sclera vasculature for a subset of the images. Additionally, the datasets ship with gender and age labels. The unique characteristics of the dataset allow us to study aspects of sclera biometrics technology that have not been studied before in the literature (e.g. vasculature segmentation techniques) as well as issues that are of key importance for practical recognition systems. Thus, next to the SBVPI dataset we also present in this paper a comprehensive investigation into sclera biometrics and the main covariates that affect the performance of sclera segmentation and recognition techniques, such as gender, age, gaze direction or image resolution. Our experiments not only demonstrate the usefulness of the newly introduced dataset, but also contribute to a better understanding of sclera biometrics in general. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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27. Poglobljen pogled v beločnično biometrijo: nova podatkovna množica in študija delovanja.
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Vitek, Matej, Rot, Peter, Štruc, Vitomir, and Peer, Peter
- Abstract
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- Published
- 2020
28. Low-Dose Atropine Induces Changes in Ocular Biometrics in Myopic Children:Exploring Temporal Changes by Linear Mixed Models and Contribution to Treatment Effect by Mediation Analyses
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Hvid-Hansen, Anders, Jacobsen, Nina, Hjortdal, Jesper, Møller, Flemming, Ozenne, Brice, Kessel, Line, Hvid-Hansen, Anders, Jacobsen, Nina, Hjortdal, Jesper, Møller, Flemming, Ozenne, Brice, and Kessel, Line
- Abstract
This study aimed to investigate changes in non-cycloplegic ocular biometrics during the initial six months of treatment with a 0.1% atropine loading dose and 0.01% atropine compared with a placebo and analyze their contribution to the treatment effect on cycloplegic spherical equivalent (SE) progression. The study was based on a randomized, double-masked, placebo-controlled, multicenter trial evaluating a 0.1% atropine six-month loading dose and 0.01% atropine in reducing myopic progression in Danish children. The treatment phase was 24 months, and the washout phase was 12 months. Parameters measured included changes in axial length (AL), anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and choroidal thickness (ChT), while cycloplegic SE and lens power were calculated. Longitudinal changes and contributions to treatment effects were analyzed using constrained linear mixed models and mediation analyses, respectively. After six months, AL was 0.13 mm shorter (95% confidence interval [CI], −0.18 to −0.07 [adjusted p < 0.001]) and 0.06 mm shorter (95% CI, −0.11 to −0.01 [adjusted p = 0.060]) with a 0.1% atropine loading dose and 0.01% atropine, respectively, compared to the placebo group. Similar concentration-dependent changes were found with ACD, LT, VCD, ChT, and cycloplegic SE. Although the treatment effects trended toward concentration-dependent responses, only the treatment effect mediated by AL at three months differed significantly between 0.01% atropine and a 0.1% atropine loading dose (adjusted p = 0.023). Several ocular biometrics, including AL, ACD, and LT, changed dose-dependently during low-dose atropine treatment. Moreover, the treatment effect of atropine on SE progression was mediated by a subset of ocular biometrics, mainly AL, with trends toward concentration dependency and distributional shifts over time. Keywords: myopia; low-dose atropine; ocular biometrics; axial length; spherical equivalent, This study aimed to investigate changes in non-cycloplegic ocular biometrics during the initial six months of treatment with a 0.1% atropine loading dose and 0.01% atropine compared with a placebo and analyze their contribution to the treatment effect on cycloplegic spherical equivalent (SE) progression. The study was based on a randomized, double-masked, placebo-controlled, multicenter trial evaluating a 0.1% atropine six-month loading dose and 0.01% atropine in reducing myopic progression in Danish children. The treatment phase was 24 months, and the washout phase was 12 months. Parameters measured included changes in axial length (AL), anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and choroidal thickness (ChT), while cycloplegic SE and lens power were calculated. Longitudinal changes and contributions to treatment effects were analyzed using constrained linear mixed models and mediation analyses, respectively. After six months, AL was 0.13 mm shorter (95% confidence interval [CI], −0.18 to −0.07 [adjusted p < 0.001]) and 0.06 mm shorter (95% CI, −0.11 to −0.01 [adjusted p = 0.060]) with a 0.1% atropine loading dose and 0.01% atropine, respectively, compared to the placebo group. Similar concentration-dependent changes were found with ACD, LT, VCD, ChT, and cycloplegic SE. Although the treatment effects trended toward concentration-dependent responses, only the treatment effect mediated by AL at three months differed significantly between 0.01% atropine and a 0.1% atropine loading dose (adjusted p = 0.023). Several ocular biometrics, including AL, ACD, and LT, changed dose-dependently during low-dose atropine treatment. Moreover, the treatment effect of atropine on SE progression was mediated by a subset of ocular biometrics, mainly AL, with trends toward concentration dependency and distributional shifts over time.
- Published
- 2023
29. Low-Dose Atropine Induces Changes in Ocular Biometrics in Myopic Children: Exploring Temporal Changes by Linear Mixed Models and Contribution to Treatment Effect by Mediation Analyses
- Author
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Anders Hvid-Hansen, Nina Jacobsen, Jesper Hjortdal, Flemming Møller, Brice Ozenne, and Line Kessel
- Subjects
spherical equivalent ,General Medicine ,myopia ,axial length ,low-dose atropine ,ocular biometrics - Abstract
This study aimed to investigate changes in non-cycloplegic ocular biometrics during the initial six months of treatment with a 0.1% atropine loading dose and 0.01% atropine compared with a placebo and analyze their contribution to the treatment effect on cycloplegic spherical equivalent (SE) progression. The study was based on a randomized, double-masked, placebo-controlled, multicenter trial evaluating a 0.1% atropine six-month loading dose and 0.01% atropine in reducing myopic progression in Danish children. The treatment phase was 24 months, and the washout phase was 12 months. Parameters measured included changes in axial length (AL), anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and choroidal thickness (ChT), while cycloplegic SE and lens power were calculated. Longitudinal changes and contributions to treatment effects were analyzed using constrained linear mixed models and mediation analyses, respectively. After six months, AL was 0.13 mm shorter (95% confidence interval [CI], −0.18 to −0.07 [adjusted p < 0.001]) and 0.06 mm shorter (95% CI, −0.11 to −0.01 [adjusted p = 0.060]) with a 0.1% atropine loading dose and 0.01% atropine, respectively, compared to the placebo group. Similar concentration-dependent changes were found with ACD, LT, VCD, ChT, and cycloplegic SE. Although the treatment effects trended toward concentration-dependent responses, only the treatment effect mediated by AL at three months differed significantly between 0.01% atropine and a 0.1% atropine loading dose (adjusted p = 0.023). Several ocular biometrics, including AL, ACD, and LT, changed dose-dependently during low-dose atropine treatment. Moreover, the treatment effect of atropine on SE progression was mediated by a subset of ocular biometrics, mainly AL, with trends toward concentration dependency and distributional shifts over time.Keywords: myopia; low-dose atropine; ocular biometrics; axial length; spherical equivalent This study aimed to investigate changes in non-cycloplegic ocular biometrics during the initial six months of treatment with a 0.1% atropine loading dose and 0.01% atropine compared with a placebo and analyze their contribution to the treatment effect on cycloplegic spherical equivalent (SE) progression. The study was based on a randomized, double-masked, placebo-controlled, multicenter trial evaluating a 0.1% atropine six-month loading dose and 0.01% atropine in reducing myopic progression in Danish children. The treatment phase was 24 months, and the washout phase was 12 months. Parameters measured included changes in axial length (AL), anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and choroidal thickness (ChT), while cycloplegic SE and lens power were calculated. Longitudinal changes and contributions to treatment effects were analyzed using constrained linear mixed models and mediation analyses, respectively. After six months, AL was 0.13 mm shorter (95% confidence interval [CI], −0.18 to −0.07 [adjusted p < 0.001]) and 0.06 mm shorter (95% CI, −0.11 to −0.01 [adjusted p = 0.060]) with a 0.1% atropine loading dose and 0.01% atropine, respectively, compared to the placebo group. Similar concentration-dependent changes were found with ACD, LT, VCD, ChT, and cycloplegic SE. Although the treatment effects trended toward concentration-dependent responses, only the treatment effect mediated by AL at three months differed significantly between 0.01% atropine and a 0.1% atropine loading dose (adjusted p = 0.023). Several ocular biometrics, including AL, ACD, and LT, changed dose-dependently during low-dose atropine treatment. Moreover, the treatment effect of atropine on SE progression was mediated by a subset of ocular biometrics, mainly AL, with trends toward concentration dependency and distributional shifts over time.
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- 2023
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30. Electronic devices and myopic refraction among children aged 6‐14 years in urban areas of Tianjin, China.
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Liu, Shengxin, Ye, Sheng, Xi, Wei, and Zhang, Xin
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- *
ELECTRONIC equipment , *METROPOLITAN areas , *SMARTPHONES , *MULTIPLE regression analysis , *VISUAL accommodation - Abstract
Purpose: To assess associations between different types of electronic devices, myopic refraction and ocular biometric parameters in children aged 6–14 years in urban areas of Tianjin, China. Methods: A school‐based, cross‐sectional study was performed on 566 children (302 boys and 264 girls). The children underwent a comprehensive eye examination, including cycloplegic autorefraction and ocular biometry. The children's parents completed a detailed questionnaire that included each child's demographics, the use of electronic devices and other related risk factors. Results: Myopia was not associated with time spent using various electronic devices. However, the mean spherical equivalent refraction (SER) decreased by 0.28 D (p = 0.042) and 0.33 D (p = 0.018) for each 1‐h increase in the time spent using smart phones and computers, respectively. In the multiple linear regression analyses of factors associated with the SER, the standardised coefficient B for time spent reading and writing was approximately four to five times larger than the standardised coefficient for time spent using smart phones or computers. Time spent using tablets and watching television was not significantly associated with the SER. A longer axial length (AL) was associated with more time spent using smart phones (B = 0.23, p = 0.006) and computers (B = 0.26, p = 0.002) but not using tablets (p = 0.45) and watching television (p = 0.45). No significant association was found between other ocular biometric parameters and time spent using various electronic devices. Conclusions: On average, a more myopic SER and longer AL were both associated with more time spent using smart phones and computers, but not with time spent using tablets and watching television. The magnitude of the association between SER and time spent reading and writing was a substantially larger than that for smart phone or computer use. Different types of electronic devices had differing levels of association with myopic refraction. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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31. IPAD: Iterative pruning with activation deviation for sclera biometrics.
- Author
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Vitek, Matej, Bizjak, Matic, Peer, Peter, and Štruc, Vitomir
- Subjects
SCLERA ,BIOMETRY ,HEAD-mounted displays ,HUMAN fingerprints ,COMPUTATIONAL complexity - Abstract
The sclera has recently been gaining attention as a biometric modality due to its various desirable characteristics. A key step in any type of ocular biometric recognition, including sclera recognition, is the segmentation of the relevant part(s) of the eye. However, the high computational complexity of the (deep) segmentation models used in this task can limit their applicability on resource-constrained devices such as smartphones or head-mounted displays. As these devices are a common desired target for such biometric systems, lightweight solutions for ocular segmentation are critically needed. To address this issue, this paper introduces IPAD (Iterative Pruning with Activation Deviation), a novel method for developing lightweight convolutional networks, that is based on model pruning. IPAD uses a novel filter-activation-based criterion (ADC) to determine low-importance filters and employs an iterative model pruning procedure to derive the final lightweight model. To evaluate the proposed pruning procedure, we conduct extensive experiments with two diverse segmentation models, over four publicly available datasets (SBVPI, SLD, SMD and MOBIUS), in four distinct problem configurations and in comparison to state-of-the-art methods from the literature. The results of the experiments show that the proposed filter-importance criterion outperforms the standard L 1 and L 2 approaches from the literature. Furthermore, the results also suggest that: (i) the pruned models are able to retain (or even improve on) the performance of the unpruned originals, as long as they are not over-pruned, with RITnet and U-Net at 50% of their original FLOPs reaching up to 4 % and 7 % higher IoU values than their unpruned versions, respectively, (ii) smaller models require more careful pruning, as the pruning process can hurt the model's generalization capabilities, and (iii) the novel criterion most convincingly outperforms the classic approaches when sufficient training data is available, implying that the abundance of data leads to more robust activation-based importance computation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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32. Accommodative Exercises to Lower Intraocular Pressure
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Jeremy Reitinger, Thomas J.W. Stokkermans, Chiu-Yen Kao, Huachun A Wang, Carol B. Toris, George Tye, and Sangeetha Ragupathy
- Subjects
Refractive error ,medicine.medical_specialty ,Intraocular pressure ,Article Subject ,genetic structures ,Scleral spur ,03 medical and health sciences ,0302 clinical medicine ,Cornea ,Ophthalmology ,Medicine ,Dioptre ,business.industry ,RE1-994 ,medicine.disease ,eye diseases ,Ciliary muscle ,medicine.anatomical_structure ,030221 ophthalmology & optometry ,Ocular biometrics ,sense organs ,business ,Accommodation ,030217 neurology & neurosurgery ,Research Article - Abstract
Purpose. This study investigated how a conscious change in ocular accommodation affects intraocular pressure (IOP) and ocular biometrics in healthy adult volunteers of different ages. Methods. Thirty-five healthy volunteers without ocular disease or past ocular surgery, and with refractive error between −3.50 and +2.50 diopters, were stratified into 20, 40, and 60 year old (y.o.) age groups. Baseline measurements of central cornea thickness, anterior chamber depth, anterior chamber angle, cornea diameter, pupil size, and ciliary muscle thickness were made by autorefraction and optical coherence tomography (OCT), while IOP was measured by pneumotonometry. Each subject’s right eye focused on a target 40 cm away. Three different tests were performed in random order: (1) 10 minutes of nonaccommodation (gazing at the target through lenses that allowed clear vision without accommodating), (2) 10 minutes of accommodation (addition of a minus 3 diopter lens), and (3) 10 minutes of alternating between accommodation and nonaccommodation (1-minute intervals). IOP was measured immediately after each test. A 20-minute rest period was provided between tests. Data from 31 subjects were included in the study. ANOVA and paired t-tests were used for statistical analyses. Results. Following alternating accommodation, IOP decreased by 0.7 mmHg in the right eye when all age groups were combined ( p = 0.029). Accommodation or nonaccommodation alone did not decrease IOP. Compared to the 20 y.o. group, the 60 y.o. group had a thicker ciliary muscle within 75 μm of the scleral spur, a thinner ciliary muscle at 125–300 μm from the scleral spur, narrower anterior chamber angles, shallower anterior chambers, and smaller pupils during accommodation and nonaccommodation ( p ’s
- Published
- 2020
33. Differential Effects on Ocular Biometrics by 0.05%, 0.025%, and 0.01% Atropine
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Shu Min Tang, Fen Fen Li, Yuzhou Zhang, Alvin L. Young, Chi Pui Pang, Ka Wai Kam, Clement C Y Tham, Li Jia Chen, and Jason C. S. Yam
- Subjects
0303 health sciences ,medicine.medical_specialty ,genetic structures ,business.industry ,Spherical equivalent ,Placebo ,Differential effects ,eye diseases ,03 medical and health sciences ,Ophthalmology ,Atropine ,0302 clinical medicine ,030221 ophthalmology & optometry ,Medicine ,Ocular biometrics ,sense organs ,Once daily ,business ,Corneal astigmatism ,Volume concentration ,030304 developmental biology ,medicine.drug - Abstract
Purpose To evaluate changes in ocular biometrics in groups receiving 0.05%, 0.025%, and 0.01% atropine compared with placebo over 1 year based on the Low-Concentration Atropine for Myopia Progression (LAMP) study. Design Double-blinded, randomized, placebo-controlled trial. Participants Three hundred eighty-three children aged 4 to 12 years who were assigned randomly to receive 0.05%, 0.025%, 0.01% atropine, or placebo once daily in both eyes and completed the first year of the LAMP study. Methods Cycloplegic spherical equivalent (SE), axial length (AL), corneal curvature (K), and anterior chamber depth (ACD) were measured by IOLMaster. Corneal astigmatism and lens power were calculated. The ocular biometric parameter changes were compared among groups. Contributions to SE progression from ocular parameters were determined and compared among groups. Main Outcome Measures Changes in ocular biometrics and their associations with the changes in SE. Results Over 1 year, changes in AL were 0.20 ± 0.25 mm, 0.29 ± 0.20 mm, 0.36 ± 0.29 mm, and 0.41 ± 0.22 mm in the 0.05% atropine, 0.025% atropine, 0.01% atropine, and placebo groups, respectively (P 0.05). Conclusions Low-concentrations of atropine (0.05%, 0.025%, and 0.01%) have no clinical effect on corneal or lens power. Antimyopic effects of low-concentration atropine act mainly on reducing AL elongation, and therefore could reduce the risk of subsequent myopia complications.
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- 2020
34. Convolutional neural networks for ocular smartphone-based biometrics.
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Ahuja, Karan, Islam, Rahul, Barbhuiya, Ferdous A., and Dey, Kuntal
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ARTIFICIAL neural networks , *SMARTPHONES , *BIOMETRIC identification , *SIGNAL convolution , *MACHINE learning - Abstract
Ocular biometrics in the visible spectrum has emerged as an area of significant research activity. In this paper, we propose a hybrid convolution-based model, for verifying a pair of periocular images containing the iris. We compose the hybrid model as a combination of an unsupervised and a supervised convolution neural network, and augment the combination with the well-known geometry-based Root SIFT model. We also compare the performance of both convolution-based models against each other, as well as, with the baseline Root SIFT. In the first (unsupervised w.r.t target dataset) convolution based deep learning approach, we use a stacked convolutional architecture, using external models learned a-priori on external facial and periocular data, on top of the baseline Root SIFT model applied on the provided data, and apply different score fusion models. In the second (supervised w.r.t target dataset) approach, we again use a stacked convolution architecture; but here, we learn the feature vector in a supervised manner. On the MICHE-II dataset, we obtain an AUROC of 0.946 and 0.981, and EER of 0.092 and 0.066, for the two models respectively. The hybrid model we propose, which combines these two convolutional neural networks, outperforms the constituents, in case both images arise from the same device type, but not necessarily so otherwise, obtaining a AUROC of 0.986 and EER of 0.053. We also benchmark our performance on the standard VISOB database, where we outperform the state of the art methods, achieving a TPR of 99.5% at a FPR of 0.001%. Given the robustness and significant performance of our methodology, our system can be used in practical applications with minimal error. [ABSTRACT FROM AUTHOR]
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- 2017
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35. Ocular biometrics in the visible spectrum: A survey.
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Rattani, Ajita and Derakhshani, Reza
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BIOMETRY , *FEATURE extraction , *VISIBLE spectra , *RECOGNITION (Psychology) , *NEAR infrared radiation - Abstract
Ocular biometrics encompasses the imaging and use of characteristic features extracted from the eyes for personal recognition. Ocular biometric modalities in visible light have mainly focused on iris, blood vessel structures over the white of the eye (mostly due to conjunctival and episcleral layers), and periocular region around eye. Most of the existing studies on iris recognition use the near infrared spectrum. However, conjunctival vasculature and periocular regions are imaged in the visible spectrum. Iris recognition in the visible spectrum is possible for light color irides or by utilizing special illumination. Ocular recognition in the visible spectrum is an important research area due to factors such as recognition at a distance, suitability for recognition with regular RGB cameras, and adaptability to mobile devices. Further these ocular modalities can be obtained from a single RGB eye image, and then fused together for enhanced performance of the system. Despite these advantages, the state-of-the-art related to ocular biometrics in visible spectrum is not well known. This paper surveys this topic in terms of computational image enhancement, feature extraction, classification schemes and designed hardware-based acquisition set-ups. Future research directions are also enumerated to identify the path forward. [ABSTRACT FROM AUTHOR]
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- 2017
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36. Ocular biometrics as a function of age, gender, height, weight, and its association with spherical equivalent in children
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Abbasali Yekta, Akbar Fotouhi, Mehdi Khabazkhoob, Reza Pakzad, Mohammad Hassan Emamian, and Hassan Hashemi
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Male ,0301 basic medicine ,medicine.medical_specialty ,Biometry ,Biometrics ,Anterior Chamber ,Spherical equivalent ,Refraction, Ocular ,03 medical and health sciences ,Sex Factors ,0302 clinical medicine ,Lens thickness ,Ophthalmology ,medicine ,Humans ,Child ,Mathematics ,Body Weight ,General Medicine ,Axial length ,Refractive Errors ,Body Height ,Cross-Sectional Studies ,030104 developmental biology ,Vitreous chamber ,030221 ophthalmology & optometry ,Ocular biometrics ,Female - Abstract
Purpose: To determine the distribution of ocular biometric components, including axial length, lens thickness, and vitreous chamber depth, their relationship with personal characteristics, and spherical equivalent refraction after adjusting axial length and vitreous chamber depth for personal characteristics. Methods: Among 6- to 12-year-old children, urban subjects were selected using random cluster sampling, and in rural areas, all eligible subjects were considered for enrollment. Ocular biometrics were measured using BioGraph. Data were summarized as mean and 95% confidence intervals. Linear regression was used to investigate the relationships between the study variables. Results: Data from 4938 children were analyzed. Mean axial length, lens thickness, and vitreous chamber depth were 23.02 (95% confidence interval: 22.97–23.07) mm, 3.48 (95% confidence interval: 3.47–3.49) mm, and 20.63 (95% confidence interval: 20.59–20.66) mm, respectively. According to the multiple linear regression model, axial length and vitreous chamber depth associated positively with height (β = 0.020, P Conclusion: This cross-sectional study showed a general pattern of ocular biometric components. The axial length value was almost similar to European countries, but less than that in the Eastern and Southeast Asian populations. By increasing age, axial length and vitreous chamber depth increased while lens thickness and spherical equivalent decreased. Among all ocular biometric components, axial length was strongest determinant for spherical equivalent.
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- 2020
37. Effect of short-term peripheral myopic defocus on ocular biometrics using Fresnel 'press-on' lenses in humans
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Nabin Joshi, Steven R. Ali, Inna Samandarova, Ryo Kubota, Amitava Gupta, Arkady Selenow, and Maksud Oliva
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Adult ,Male ,medicine.medical_specialty ,Biometry ,Time Factors ,genetic structures ,Physiology ,Science ,Visual Acuity ,Refraction, Ocular ,Article ,law.invention ,Cohort Studies ,Young Adult ,law ,Ophthalmology ,Myopia ,medicine ,Humans ,Central visual field ,Vision, Ocular ,Spectacle lenses ,Multidisciplinary ,Choroid ,business.industry ,Fresnel lens ,Axial length ,Axial elongation ,eye diseases ,Peripheral ,Axial Length, Eye ,Left eye ,Eyeglasses ,Hyperopia ,Medicine ,Ocular biometrics ,Female ,sense organs ,Visual Fields ,business ,Neuroscience - Abstract
This study assessed axial length and choroidal thickness changes following short-term peripheral myopic defocus in normal adult subjects. Twenty subjects underwent defocus sessions by viewing a full-field projected movie 4 m away for 4 h in the morning, while wearing spectacle lenses, corrected for distance vision in both eyes. The right eye, serving as the test eye, was peripherally defocused using a Fresnel lens overlay of + 3.50 D with a central clear aperture of 11.5 mm (correlating to a clear central visual field of approximately 23°), while the left eye served as the control (with no Fresnel lens overlay). A subset of 10 subjects from the same cohort also underwent additional defocus sessions with + 5.00 D of peripheral defocus. Axial length was measured and radial sub-foveal choroidal scans were obtained before and after the defocus sessions. The increase in axial length of the test eyes were significantly less than the control eyes under both peripheral defocus conditions (p
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- 2021
38. Prevention of Choroidal Thinning by 0.01% Atropine Administered 24 h Before Exposure to Hyperopic Blur in Young Myopes
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Beata P. Sander
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Adult ,Atropine ,Male ,medicine.medical_specialty ,genetic structures ,Population ,White People ,Persistence (computer science) ,Young Adult ,Ophthalmology ,medicine ,Myopia ,Humans ,Pharmacology (medical) ,Young adult ,education ,Pharmacology ,education.field_of_study ,Dose-Response Relationship, Drug ,business.industry ,Choroid ,eye diseases ,medicine.anatomical_structure ,Hyperopia ,Ocular biometrics ,Female ,sense organs ,business ,medicine.drug - Abstract
Purpose: To evaluate the persistence of atropine's effect upon choroidal thickness and ocular biometrics and its interaction with hyperopic blur in a population of young adult myopes. Methods: Twen...
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- 2021
39. Sex Differences in Rate of Axial Elongation and Ocular Biometrics in Elementary School Students
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Hiroto Terasaki, Taiji Sakamoto, Ryo Asaoka, Naoya Yoshihara, Naoko Kakiuchi, and Takehiro Yamashita
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medicine.medical_specialty ,axial elongation rate ,genetic structures ,business.industry ,Clinical Ophthalmology ,Axial length ,axial length ,Axial elongation ,Ophthalmology ,Lens thickness ,school myopia ,medicine ,Ocular biometrics ,sense organs ,business ,Original Research - Abstract
Hiroto Terasaki,1,* Takehiro Yamashita,1,* Ryo Asaoka,2â 5 Naoya Yoshihara,1 Naoko Kakiuchi,1 Taiji Sakamoto1 1Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan; 2Department of Ophthalmology, Seirei Hamamatsu General Hospital, Shizuoka, Japan; 3Seirei Christopher University, Shizuoka, Japan; 4Nanovision Research Division, Research Institute of Electronics, Shizuoka University, Shizuoka, Japan; 5The Graduate School for the Creation of New Photonics Industries, Shizuoka, Japan*These authors contributed equally to this workCorrespondence: Hiroto TerasakiDepartment of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, JapanTel +81 99-275-5402Fax +81 99-265-4894Email teracchi@m2.kufm.kagoshima-u.ac.jpPurpose: To determine the relationship between the ocular biometrics and axial length (AL) elongation and its rate in elementary school children.Methods: This is a prospective observational study of 102 right eyes of third-grade elementary school students who were 8 to 9 years old. All participants underwent measurements of the AL, anterior chamber depth (ACD), and lens thickness (LT) annually for 3 years. The AL elongation during the first half and second half was calculated by subtracting the AL of the 1st year from that at the 2nd year, and AL of the 3rd year minus 2nd year. The total AL elongation (TALE) was obtained by summing up the first and second half AL elongations. The growth rate change (GRC) was obtained by subtracting the first half AL elongation from second half AL elongation. Spearman correlations were used to determine the correlation between the 1st year ocular biometrics and the TALE and GRC.Results: The mean TALE was 0.54 ± 0.26 mm in boys and 0.46 ± 0.31 mm in girls. The mean GRC was 0.00 ± 0.16 mm in boys and â 0.04 ± 0.14 mm in girls. In boys and girls, the TALE was significantly larger in the eyes with myopic ocular biometrics such as a deeper ACD, thinner LT, and longer AL during the 1st year (|r|=0.41 to 0.46, P < 0.05). The GRC was significantly accelerated in the eyes of only the girls with hyperopic ocular biometrics such as a shallower ACD, thicker LT, and shorter AL during the 1st year (|r|=0.31 to 0.41, P< 0.05).Conclusion: In boys and girls, the TALE tends to be larger in eyes with myopic biometrics at the 1st year examination. The GRC tended to accelerate in the eyes with hyperopic ocular biometry during the 1st year only in girls.Keywords: axial elongation rate, axial length, school myopia
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- 2021
40. Ocular biometrics: A survey of modalities and fusion approaches.
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Nigam, Ishan, Vatsa, Mayank, and Singh, Richa
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BIOMETRIC identification , *COMPUTER surveys , *EYE movements , *IMAGE fusion , *BENCHMARK problems (Computer science) - Abstract
Biometrics, an integral component of Identity Science , is widely used in several large-scale-county-wide projects to provide a meaningful way of recognizing individuals. Among existing modalities, ocular biometric traits such as iris, periocular, retina, and eye movement have received significant attention in the recent past. Iris recognition is used in Unique Identification Authority of India’s Aadhaar Program and the United Arab Emirate’s border security programs, whereas the periocular recognition is used to augment the performance of face or iris when only ocular region is present in the image. This paper reviews the research progression in these modalities. The paper discusses existing algorithms and the limitations of each of the biometric traits and information fusion approaches which combine ocular modalities with other modalities. We also propose a path forward to advance the research on ocular recognition by (i) improving the sensing technology, (ii) heterogeneous recognition for addressing interoperability, (iii) utilizing advanced machine learning algorithms for better representation and classification, (iv) developing algorithms for ocular recognition at a distance, (v) using multimodal ocular biometrics for recognition, and (vi) encouraging benchmarking standards and open-source software development. [ABSTRACT FROM AUTHOR]
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- 2015
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41. Ocular Anatomical and Functional Characteristics in Anisometropic Chinese Children
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Yuanyuan Zhong, Li Zeng, Jiang Liu, Zhi Chen, and Jianlong Yang
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Male ,medicine.medical_specialty ,Biometry ,genetic structures ,Adolescent ,Refraction, Ocular ,Anisometropia ,Lens thickness ,Anterior Eye Segment ,Ophthalmology ,medicine ,Myopia ,Humans ,Child ,business.industry ,Choroid ,Accommodation, Ocular ,Axial length ,medicine.disease ,Refractive Errors ,eye diseases ,Axial Length, Eye ,medicine.anatomical_structure ,Vitreous chamber ,Ocular biometrics ,Female ,sense organs ,Accommodative lag ,Negative correlation ,business ,Tomography, Optical Coherence ,Optometry - Abstract
SIGNIFICANCE This research found that anterior and posterior biometrics differ in many aspects between fellow eyes of anisometropic children. This might shed light on the mechanisms underlying the onset and progression of anisometropia and myopia. PURPOSE This study aimed to investigate the ocular biometric parameters, peripheral refraction, and accommodative lag of fellow eyes in anisometropic children. METHODS Anisometropic children were recruited. Axial length (AL), vitreous chamber depth (VCD), central corneal thickness, anterior chamber depth (ACD), lens thickness (LT), simulated K readings, central and peripheral refractive errors, and accommodative lag were measured in both eyes. The subfoveal choroidal thickness, average choroidal thickness, and choroid vessel density of the 6 × 6-mm macular area were measured by optical coherence tomography. RESULTS Thirty-two children aged 11.1 ± 1.7 years were enrolled. The average degree of anisometropia was 2.49 ± 0.88 D. The AL, VCD, ACD, and simulated K reading values were significantly larger in the more myopic eyes, whereas the LT value was significantly smaller. Subfoveal choroidal thickness (P = .001) and average choroidal thickness (P = .02) were smaller in the more myopic eyes than in the contralateral eyes, whereas choroid vessel density (P = .03) was larger. The amount of anisometropia had a significant positive correlation with the difference in AL (r = 0.869, P < .001), VCD (r = 0.853, P < .001), and ACD (r = 0.591, P < .001) and a negative correlation with the difference in LT (r = -0.457, P = .009). CONCLUSIONS Ocular biometrics differ in many aspects between the fellow eyes of anisometropic Chinese children, and the difference is correlated with the degree of anisometropia.
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- 2021
42. Lack of cone mediated retinal function increases susceptibility to form-deprivation myopia in mice
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Cara Motz, Susov Dhakal, Erica Landis, Machelle T. Pardue, Ranjay Chakraborty, Han na Park, P. Michael Iuvone, Michael A. Bergen, and Victoria Yang
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Male ,0301 basic medicine ,Refractive error ,medicine.medical_specialty ,genetic structures ,Dopamine ,Visual Acuity ,Refraction, Ocular ,Retina ,Article ,law.invention ,Mice ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,0302 clinical medicine ,law ,Ophthalmology ,Myopia ,medicine ,Animals ,Chromatography, High Pressure Liquid ,GNAT2 ,Keratometer ,Chemistry ,Retinal ,medicine.disease ,Heterotrimeric GTP-Binding Proteins ,eye diseases ,Sensory Systems ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,Retinal Cone Photoreceptor Cells ,030221 ophthalmology & optometry ,Form deprivation ,3,4-Dihydroxyphenylacetic Acid ,Ocular biometrics ,Female ,Retinal function ,Disease Susceptibility ,sense organs ,Sensory Deprivation ,Tomography, Optical Coherence ,medicine.drug - Abstract
Retinal photoreceptors are important in visual signaling for normal eye growth in animals. We used Gnat2 (cplf3/cplf3) (Gnat2(−/−)) mice, a genetic mouse model of cone dysfunction to investigate the influence of cone signaling in ocular refractive development and myopia susceptibility in mice. Refractive development under normal visual conditions was measured for Gnat2(−/−) and age-matched Gnat2(+/+) mice, every 2 weeks from 4 to 14 weeks of age. Weekly measurements were performed on a separate cohort of mice that underwent monocular form-deprivation (FD) in the right eye from 4 weeks of age using head-mounted diffusers. Refraction, corneal curvature, and ocular biometrics were obtained using photorefraction, keratometry and optical coherence tomography, respectively. Retinas from FD mice were harvested, and analyzed for dopamine (DA) and 3,4-dihydroxyphenylacetate (DOPAC) using high-performance liquid chromatography. Under normal visual conditions, Gnat2(+/+) and Gnat2(−/−) mice showed similar refractive error, axial length, and corneal radii across development (p>0.05), indicating no significant effects of the Gnat2 mutation on normal ocular refractive development in mice. Three weeks of FD produced a significantly greater myopic shift in Gnat2(−/−) mice compared to Gnat2(+/+) controls (−5.40 ± 1.33 D vs −2.28 ± 0.28 D, p=0.042). Neither the Gnat2 mutation nor FD altered retinal levels of DA or DOPAC. Our results indicate that cone pathways needed for high acuity vision in primates are not as critical for normal refractive development in mice, and that both rods and cones contribute to visual signalling pathways needed to respond to FD in mammalian eyes.
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- 2019
43. Effect of 0.02% and 0.01% atropine on ocular biometrics: A two-year clinical trial.
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Wang M, Cui C, Yu SA, Liang LL, Ma JX, and Fu AC
- Abstract
Background: Several studies have shown that various concentrations of low-concentration atropine can reduce myopia progression and control axial elongation safely and efficiently in children. The aim of this study was to evaluate the effects of 0.02% and 0.01% atropine on ocular biometrics., Methods: Cohort study. 138 and 142 children were randomized to use either 0.02% or 0.01% atropine eye drops, respectively. They wore single-vision (SV) spectacles, with one drop of atropine applied to both eyes nightly. Controls ( N = 120) wore only SV spectacles. Ocular and corneal astigmatism were calculated using Thibos vector analysis and split into J0 and J45., Results: The changes in cycloplegic spherical equivalent refraction (SER) and axial length (AL) were -0.81 ± 0.52D, -0.94 ± 0.59D, and -1.33 ± 0.72D; and 0.62 ± 0.29 mm, 0.72 ± 0.31 mm, and 0.89 ± 0.35 mm in the 0.02% and 0.01% atropine and control groups, respectively (all P < 0.05). Both anterior chamber depth (ACD) and ocular astigmatism (including J0) increased, and lens power decreased in the three groups (all P < 0.05). However, there were no differences in the changes in ACD, ocular astigmatism, and lens power among the three groups (all P > 0.05). Intraocular pressure (IOP), corneal curvature, ocular astigmatism J45, and corneal astigmatism (including J0 and J45) remained stable over time in the three groups (all P > 0.05). The contributions to SER progression from the changes in AL, lens and corneal power of the three groups were similar ( P > 0.05). The contribution of AL change alone to the change in SER was 56.3%, 63.4% and 78.2% in the above corresponding three groups., Conclusions: After 2 years, 0.02% and 0.01% atropine had no clinical effects on corneal and lens power, ocular and corneal astigmatism, ACD or IOP compared to the control group. 0.02% and 0.01% atropine helped to control myopia progression mainly by reducing AL elongation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Wang, Cui, Yu, Liang, Ma and Fu.)
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- 2023
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44. VISOB 2.0 - The Second International Competition on Mobile Ocular Biometric Recognition
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Narsi Reddy, Hoang Mark Nguyen, Ajita Rattani, and Reza Derakhshani
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biology ,Biometrics ,Computer science ,business.industry ,Deep learning ,Speech recognition ,Word error rate ,Curitiba ,020207 software engineering ,02 engineering and technology ,biology.organism_classification ,Competition (economics) ,0202 electrical engineering, electronic engineering, information engineering ,Ocular biometrics ,020201 artificial intelligence & image processing ,Artificial intelligence ,business - Abstract
Following the success of VISOB 1.0 visible light ocular biometrics competition at IEEE ICIP 2016, we organized VISOB 2.0 competition at IEEE WCCI 2020. The aim of VISOB 2.0 competition was to evaluate and compare the performance of ocular biometrics recognition approaches in visible light using (a) stacks of five images captured in burst mode and (b) subject-independent evaluation, where subjects do not overlap between training and testing set. We received three submissions in which the authors developed various deep learning based and texture-analysis based methods. The best results were obtained by a team from Federal University of Parana (Curitiba, Brazil), achieving an Equal Error Rate (EER) of \(5.25\%\) in a subject-independent evaluation setting.
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- 2021
45. Probing Fairness of Mobile Ocular Biometrics Methods Across Gender on VISOB 2.0 Dataset
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Ajita Rattani, Ali Almadan, and Anoop Krishnan
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021110 strategic, defence & security studies ,Authentication ,Facial expression ,Biometrics ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Computer science ,Deep learning ,0211 other engineering and technologies ,Usability ,02 engineering and technology ,Statistics ,0202 electrical engineering, electronic engineering, information engineering ,Ocular biometrics ,020201 artificial intelligence & image processing ,Artificial intelligence ,business ,Mobile device - Abstract
Recent research has questioned the fairness of face-based recognition and attribute classification methods (such as gender and race) for dark-skinned people and women. Ocular biometrics in the visible spectrum is an alternate solution over face biometrics, thanks to its accuracy, security, robustness against facial expression, and ease of use in mobile devices. With the recent COVID-19 crisis, ocular biometrics has a further advantage over face biometrics in the presence of a mask. However, fairness of ocular biometrics has not been studied till now. This first study aims to explore the fairness of ocular-based authentication and gender classification methods across males and females. To this aim, VISOB 2.0 dataset, along with its gender annotations, is used for the fairness analysis of ocular biometrics methods based on ResNet-50, MobileNet-V2 and lightCNN-29 models. Experimental results suggest the equivalent performance of males and females for ocular-based mobile user-authentication in terms of genuine match rate (GMR) at lower false match rates (FMRs) and an overall Area Under Curve (AUC). For instance, an AUC of 0.96 for females and 0.95 for males was obtained for lightCNN-29 on an average. However, males significantly outperformed females in deep learning based gender classification models based on ocular-region.
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- 2021
46. A standoff system for noncooperative ocular biometrics.
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Doynov, Plamen and Derakhshani, Reza
- Abstract
The iris and more recently vascular patterns seen on the white of the eye have been considered for ocular biometrics. The non-contact nature, uniqueness, and permanence of ocular features makes them promising. Among new challenges are to develop commercial systems for less constrained environments and at extended distances. Such systems need to have minimal burden on the user and be robust for non-cooperative users. We present the design and development of standoff system for noncooperative ocular biometrics using system integration approach. Review of existing commercial and experimental long-range biometric systems is presented. The process of selection of sensors and illumination techniques is described. The development of user interfaces and algorithms for a working prototype is explained. The performance is evaluated with images of 28 subjects, acquired at distances up to 9 meters. The conflicting requirements for the design of this standoff biometric system, and the resulting performance limitations with impact on image quality are discussed. [ABSTRACT FROM PUBLISHER]
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- 2012
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47. Ocular biometrics databases: Standards and data interchange formats.
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Doynov, Plamen and Derakhshani, Reza
- Abstract
The current challenges to developing commercial Ocular Biometric systems are to create applications that tolerate unconstrained environments. Designs for sensors, user interfaces, and algorithms must perform well under variable illumination, poses, and camera distances, with low-quality images, and within other real-world conditions. Practical deployment requires interoperability of data and processing algorithms from multiple systems. Facilitating meaningful progress ultimately demands Biometric Databases that contain real-world data. Accelerated standardization offers practical means to organize the tremendous volume of emerging biometric information. Standards enable data exchanges that are grounded on comparable and compatible formats. This paper describes the development of a research-oriented Ocular Biometric Database that contains images acquired in conditions relevant to unconstrained environments. The data was collected with different sensors and imaging systems under diverse conditions representing real-world applications. Images and related data were stored in a database adhering to extended biometric standards requirements and biometric data-interchange formats. Assessment and applicability reviews were performed on existing national and international standards pertaining to ocular biometrics and were used during the development. The paper describes the design approach with a goal to achieve interoperability and standardization of data and results. It also addresses recent developments in biometric data acquisition, pre- and post-processing, information storage, exchange, and access control. [ABSTRACT FROM PUBLISHER]
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- 2012
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48. Myopic anisometropia: ocular characteristics and aetiological considerations.
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Vincent, Stephen J, Collins, Michael J, Read, Scott A, and Carney, Leo G
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ANISOMETROPIA , *REFRACTIVE errors , *MYOPIA , *OCULAR dominance , *ETIOLOGY of diseases , *BIOMETRIC eye scanning systems - Abstract
Anisometropia represents a unique example of ocular development, where the two eyes of an individual, with an identical genetic background and seemingly subject to identical environmental influences, can grow asymmetrically to produce significantly different refractive errors. This review provides an overview of the research examining myopic anisometropia, the ocular characteristics underlying the condition and the potential aetiological factors involved. Various mechanical factors are discussed, including corneal structure, intraocular pressure and forces generated during near work that may contribute to development of anisomyopia. Potential visually guided mechanisms of unequal ocular growth are also explored, including the influence of astigmatism, accommodation, higher-order aberrations and the choroidal response to altered visual experience. The association between binocular vision, ocular dominance and asymmetric refraction is also considered, along with a review of the genetic contribution to the aetiology of myopic anisometropia. Despite a significant amount of research into the biomechanical, structural and optical characteristics of anisometropic eyes, there is still no unifying theory, which adequately explains how two eyes within the same visual system grow to different endpoints. [ABSTRACT FROM AUTHOR]
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- 2014
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49. A longitudinal study of the effect of ocular biometrics measures on myopia onset
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Minjuan Zhu, Yang Yu, Jun Zhao, Shan Li, Shuiqiang Chen, Hong-Wei Deng, Hua-hong Zhong, and Zhengyang Tao
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Male ,medicine.medical_specialty ,Refractive error ,Longitudinal study ,Biometry ,Adolescent ,Spherical equivalent ,Refraction, Ocular ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Ophthalmology ,medicine ,Myopia ,Humans ,Longitudinal Studies ,Child ,business.industry ,High myopia ,Axial length ,medicine.disease ,Sensory Systems ,Confidence interval ,Axial Length, Eye ,Linear relationship ,030221 ophthalmology & optometry ,Ocular biometrics ,030211 gastroenterology & hepatology ,Female ,business - Abstract
To investigate the relationship between ocular biometrics (OB) and myopia onset. OB data from students in 4 grades (aged from 6 to 14 years) in China were collected in a 1.5-year longitudinal study. Refractive error was assessed with cycloplegic autorefraction. At baseline, 934 (56.33%) of the subjects (right eye) had myopia. The mean spherical equivalent (SE) and axial length to corneal radius (AL/CR) were − 2.14 ± 1.49 and 3.14 ± 0.11, respectively, in the subjects with myopia and − 0.09 ± 0.21 and 2.98 ± 0.07, respectively, in the subjects without myopia. The correlation between the SE and AL/CR was r = − 0.823 (P < 0.001). The slopes of the SE changing with the AL/CR (and R-squares) were − 0.28 to − 1.80 (0.01–0.14) in the no myopia group, − 3.40 to − 6.20 (0.20–0.48) in the low myopia group, and − 3.37 to − 11.34 (0.16–0.74) in the moderate and high myopia groups. The baseline AL/CR values in grades 1, 3, and 5 were higher in those who developed myopia within 1.5 years. The odds ratio of the AL/CR to myopia onset in 1.5 years was 1.096 (95% confidence interval (CI): 1.060–1.135). Of the five indicators, the AL/CR showed the best correlation with the SE. The adjoint and linear relationship between the AL/CR and the SE tended to increase with SE progression. When myopia progressed beyond a certain range, the AL/CR was significantly different in those without initial myopia who developed it within 1.5 years compared with those who did not. After adjusting for age, sex, school, and grade, the interpretation capability of the current AL/CR to myopia onset in 1.5 years was limited.
- Published
- 2020
50. Towards adept hand-crafted features for ocular biometrics
- Author
-
Ritesh Vyas
- Subjects
Modality (human–computer interaction) ,business.industry ,Computer science ,Iris recognition ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,medicine.anatomical_structure ,Feature descriptor ,Benchmark (computing) ,medicine ,Ocular biometrics ,Periocular Region ,Segmentation ,Computer vision ,Artificial intelligence ,Iris (anatomy) ,business - Abstract
This article presents a hand-crafted feature descriptor for ocular recognition, which as opposed to the deep-learning based approaches, is free from any kind of learning. The proposed approach is able to mitigate the limitations of iris recognition, such as poor iris segmentation, partial or covered iris. The proposed approach leverages by the unique texture present in the periocular region, which can provide complementary details along with the iris modality, or can act as a potential stand alone trait. The proposed descriptor is evaluated on three benchmark databases, namely VISOB, CrossEyed and MICHE. Two of these databases (VISOB and MICHE) provide eye images captured through the smartphones, whereas the third database provides standard eye images registered in visible as well as near-infrared wavelengths. Hence, the evaluation reported in this article becomes a comprehensive one. The experimental results exhibit that the proposed approach proves to be suitable in challenging evaluation frameworks.
- Published
- 2020
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