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The removal of hydrogen sulfide (H2S) from contaminated airstream was studied in a biotrickling filter (BTF) packed with open-pore polyurethane foam as a carrier of Thiobacillus thioparus (DSMZ5368) with counter current gas/liquid flows. The effect of operating parameters on BTF performance was studied. Experiments were performed at different Empty Bed Residence Times (EBRT) from 9 to 45 seconds, and different initial H2S concentration from 25 to 85 ppm. The results showed reasonable performance of the BTF, in H2S removal from the synthetic gas stream. However, the performance was somewhat lower than other studies in BTF in which either Thiobacillus thioparus with other packings or polyurethane foam with other microbial cultures were used. The effect of liquid recirculation rate (LRR) in the range of 175-525 ml/min (0.46-1.34 m/h) on BTF performance was also studied. Results showed that increasing LRR from 175 to 350 mL/min resulted in significant enhancement of H2S removal efficiency, but further increase in LRR up to 525 mL/min had an insignificant effect. H2S elimination at different heights of the bed was studied and it was found that decrease in EBRT results in more homogeneous removal of the pollutant in BTF. Determination of microbial species in the BTF after 100 days performance showed that during BTF operation the only H2S degrading specie was Thiobacillus thioparus. [ABSTRACT FROM AUTHOR]

Purpose: To determine the mean value and normative distribution of intraocular pressure (IOP) in children and their association with demographic and ocular biometrics., Methods: Cluster sampling was done to select the students in urban areas of Shahroud, northeast Iran, while all students living in rural areas were selected. IOP was measured in mmHg using a non-contact tonometer, along with corneal and retinal imaging and ocular biometric measurement., Results: After applying the exclusion criteria, 9154 eyes of 4580 students were analyzed, of whom 2377 (51.9 %) were boys. The mean age of the participants was 12.35±1.73 years (range: 9-15 years). The mean IOP was 15.58±2.83 (15.47-15.69) in total, 15.31±2.77 (15.17-15.46) in boys, and 15.88±2.86 (15.73-16.03) in girls (p < 0.001). The mean IOP was 15.07 and 15.49 in students aged 9 and 15 years, respectively. The mean IOP was 15.7 ± 2.64 (15.58-15.81) in urban and 14.52±4.05 (14.27-14.77) in rural students (p < 0.001). In the multiple generalized estimating equation model, IOP had a positive association with female sex (β=0.84, P < 0.001), systolic blood pressure (β=0.02, P < 0.001), cup volume (β=0.99, P < 0.001), corneal thickness (β=0.04, P < 0.001) and anterior chamber volume (β=0.007, P < 0.001) and a negative association with living in the rural area (β=-0.65, P < 0.001), rim area (β=-0.39, P < 0.001), and corneal diameter (β=-0.18, P = 0.045). Furthermore, individuals with myopia exhibited a significantly higher IOP (β=0.35, P < 0.001) compared to those with emmetropia., Conclusion: This study showed the normative distribution of IOP and its associated factors in children. The results can be used in diagnosis and management of glaucoma., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2024 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.)

Purpose: To determine the distribution of macular thickness and macular volume in an elderly healthy population 60 years of age and above and their determinants., Methods: The sampling was performed using a multistage stratified random cluster sampling method on the geriatric population 60 years of age and above in Tehran, Iran. All participants underwent optometric examinations, slit-lamp examination, and optical biometry. Retinal imaging was performed by spectral-domain optical coherence tomography., Results: The means ± standard deviation and 95% confidence interval of central macular thickness (CMT), average macular thickness (AMT), and macular volume were 221 ± 33 (218-223) μm, 267 ± 29 (265-269) μm, and 8.36 ± 0.44 (8.33-8.39) mm 3 , respectively. The CMT was significantly lower in females than males (β: -5.77; P = 0.002). The AMT was significantly lower in females than males (β = -10.32; P < 0.001) and was significantly directly related to intraocular pressure (β = 0.63; P = 0.038). The macular volume was significantly lower in females than males (β = -0.13; P < 0.001) and decreased with age (β = -0.01; P < 0.001). In addition, the macular volume had a significant inverse and direct relationship with axial length (β = -0.04; P = 0.011) and keratometry (β = 0.03; P < 0.001)., Conclusions: Macular thickness in the Iranian geriatric population was slightly less than the populations studied in other countries. The role of sex should also be taken into account in the interpretation of macular thickness findings., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Journal of Current Ophthalmology.)

Aim: To determine the normative distribution of axial length (AL), anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), and some of their associated factors in subjects aged 60 and over., Methods: In this cross-sectional study, 160 clusters were sampled using multi-stage cluster sampling in Tehran, Iran. After a preliminary interview, the participants underwent optometric examinations including visual acuity and refraction measurement followed by slit lamp biomicroscopy. Finally, ocular imaging was done using the Pentacam AXL to measure AL, ACD, ACV, and ACA., Results: A total of 4519 eyes of 2436 participants were evaluated, of whom 58.0% ( n =1412) were female. The mean age of the subjects was 67.32±6.05y (range: 60-95y). The mean AL, ACD, ACV, and ACA was 23.22 mm (23.18-23.27 mm), 2.61 mm (2.59-2.62 mm), 126.56 mm 3 (125.08-128.04 mm 3 ), and 30.61° (30.3°-30.92°), respectively. In the multivariable model, after adjusting for the effect of both eyes, the longest and shortest AL was seen in myopic and hyperopic subjects, respectively. AL, ACD, ACV and ACA were significantly larger in men compared to women ( P <0.001). Except ACA, other evaluated parameters showed an inverse correlation with age ( P <0.001), however, this correlation was insignificant for AL ( P =0.623)., Conclusion: Normative value of AL, and other biometric parameters are specific for each ethnicity, age and sex group. Any alteration in these parameters and their effect on refraction should be considered in this age group, especially in case of cataract surgery., (International Journal of Ophthalmology Press.)

Objectives: This study evaluated the relationship between acquired cataract's different types and the ABO and Rh blood classes., Methods: Overall, 520 patients, by randomized sampling method, participated in this retrospective cross-sectional study. After reviewing the patient's medical records and laboratory results, the patient's demographics, ABO group, Rh, and cataract type were documented., Results: A total of 520 patients were included in the research, with a mean age of 67.57 ± 11.85. Most of them were female (n = 286, 55%). Mix (n = 230, 44%) and nuclear sclerotic (NS) (n = 167, 32%) cataracts were the most common types. The posterior subcapsular cataract (PSC) prevalence in females was significantly higher than in males (16.1% vs.7.3% p = 0.002). Also, men had more NS cataracts than females (89, 38% vs. 78, 27.3%) (p = 0.009). Patients with PSC were significantly younger than others (all p-values < 0.001). Our results showed that cataract types are independent of blood group types and Rh (P > 0.05)., Conclusion: Although our findings showed that cataract types are independent of blood group types and Rh, they can be compared with future studies on the association of other Blood-Group Systems in developing acquired cataracts., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Aim: To collect and present updated evidence about epidemiological aspects of retinoblastoma (Rb) in the world., Methods: A comprehensive search without the time and language restrictions was conducted in international databases, including MEDLINE, Scopus, Web of Science, and PubMed. The search keywords were "retinoblastoma" OR "retinal Neuroblastoma" OR "retinal glioma" OR "retinoblastoma eye cancer" OR "retinal glioblastoma"., Results: The worldwide incidence of Rb is 1 in 16 000-28 000 live births, but was higher in developing compared to developed countries. Several attempts for improving early detection and treatment had increased the Rb survival rate from 5% to 90% in developed countries over the past decade, but its survival was lower in developing countries (about 40% in low-income countries) and the majority of mortalities occurred in developing countries. The etiology of Rb could be viewed as genetics in the heritable form and environmental and lifestyle factors in the sporadic form. Some environmental risk factors such as in vitro fertilization; insect sprays; father's occupational exposure to oil mists in metal working, and poor living conditions might play a role in the occurrence of the disease. Although ethnicity might affect Rb incidence, sex has no documented effect and the best treatment approaches were now ophthalmic artery chemosurgery and intravitreal chemotherapy., Conclusion: Determining the role of genetics and environmental factors helps to accurately predict the prognosis and identify the mechanism of the disease, which can reduce the risk of tumor development., (International Journal of Ophthalmology Press.)

Research conducted on mobile apps providing mental health services has concluded that patients with mental disorders tend to use such apps to maintain mental health balance technology may help manage and monitor issues like bipolar disorder (BP). This study was conducted in four steps to identify the features of designing a mobile application for BP-affected patients including (1) a literature search, (2) analyzing existing mobile apps to examine their efficiency, (3) interviewing patients affected with BP to discover their needs, and 4) exploring the points of view of experts using a dynamic narrative survey. Literature search and mobile app analysis resulted in 45 features, which were later reduced to 30 after the experts were surveyed about the project. The features included the following: mood monitoring, sleep schedule, energy level evaluation, irritability, speech level, communication, sexual activity, self-confidence level, suicidal thoughts, guilt, concentration level, aggressiveness, anxiety, appetite, smoking or drug abuse, blood pressure, the patient's weight and the side effects of medication, reminders, mood data scales, diagrams or charts of the collected data, referring the collected data to a psychologist, educational information, sending feedbacks to patients using the application, and standard tests for mood assessment. The first phase of analysis should consider an expert and patient view survey, mood and medication tracking, as well as communication with other people in the same situation are the most features to be considered. The present study has identified the necessity of apps intended to manage and monitor bipolar patients to maximize efficiency and minimize relapse and side effects., Competing Interests: Conflict of InterestThe authors declare no competing interests., (© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Aim: To determine the distribution and associated factors of intraocular pressure (IOP) in an Iranian elderly population 60 years of age and above., Methods: The present report is part of the Tehran Geriatric Eye study (TGES), a population-based cross-sectional study that was conducted on the residents of Tehran 60 years of age and above. The sampling was performed using multistage stratified random cluster sampling methods from 22 districts of Tehran, Iran. Demographic and history information, blood samples, and blood pressure were collected from all participants. Ocular examinations included measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, and slit-lamp biomicroscopy. The IOP was measured using Goldmann applanation tonometry (GAT). Corneal imaging and ocular biometry were performed using Pentacam AXL., Results: The data of 3892 eyes of 2124 individuals were analyzed for this report. The mean age of the study participants was 66.49±5.31y (range: 60 to 95y). The mean IOP was 15.2 mm Hg (95%CI: 15.1 to 15.4), 15.3 mm Hg (95%CI: 15.1 to 15.5) and 15.1 mm Hg (95%CI: 15.0 to 15.3) in all participants, males, and females, respectively. Of the study participants, 1.3% had an IOP of ≥20 mm Hg. The mean IOP increased from 15.1 mm Hg in the age group 60-64y to 16.3 mm Hg in the age group ≥80y. According to the final multiple GEE model, the IOP was statistically significantly higher in men than in women. All the studied age groups, except for the 75-79-year-old age group, had significantly higher IOP compared to the 60-64-year-old age group. The IOP was significantly higher in underweight compared to other body mass index groups. Moreover, the IOP had a statistically significant direct relationship with the mean corneal power (mean CP), central corneal thickness (CCT), and systolic blood pressure., Conclusion: The present study presents the distribution of IOP in an Iranian elderly population. A higher IOP (within the range 14 to 17 mm Hg) is significantly associated with older age, male sex, high systolic blood pressure, increased mean CP, and CCT. These factors should be considered in the clinical interpretation of IOP., (International Journal of Ophthalmology Press.)

Objectives: This study aims to design a conceptual model for the effect of various factors on walking ability, participation, and quality of life in children with spastic diplegic cerebral palsy (SDCP) and test it based on field data using path analysis ., Materials & Methods: This cross-sectional study was performed on 181 children with SDCP. The following were used to measure each of the variables: the Modified Ashworth Scale, the Micro Manual Muscle Tester, the Timed Up and Go Test (TUG), the Boyd and Graham test, the goniometer, weight and height, the Gross Motor Function Classification System, the Life Habits Questionnaire, and cerebral palsy Quality of Life Questionnaire for Children. The structural model was tested in Amos 17., Results: All paths of the proposed model were significant (P <0.05). Among evaluated variables, muscle strength (B = -0.466), balance (B = 0.326), and spasticity (B = 0.143) affected walking ability. Moreover, as an intermediate factor, walking ability affected the subjects' participation (B = -0.819) and quality of life (B = -0.183)., Conclusion: Muscle strength, balance, and spasticity are the most influential factors in the walking ability of children with SDCP. Furthermore, walking ability and participation are two critical factors in promoting the quality of life of these children., Competing Interests: The authors declare that there is no conflict of interest.

Introduction: Silibinin is a natural flavonoid compound known to induce apoptosis in cancer cells. Despite silibinin's safety and efficacy as an anticancer drug, its effects on inducing immunogenic cell death (ICD) are largely unknown. Herein, we have evaluated the stimulating effects of silibinin on ICD in cancer cells treated with silibinin alone or in combination with chemotherapy. Methods: The anticancer effect of silibinin, alone or in combination with doxorubicin or oxaliplatin (OXP), was assessed using the MTT assay. Compusyn software was used to analyze the combination therapy data. Western blotting was conducted to examine the level of STAT3 activity. Flow cytometry was used to analyze calreticulin (CRT) and apoptosis. The heat shock protein (HSP70), high mobility group box protein1 (HMGB1), and IL-12 levels were assessed by ELISA. Results: Compared to the negative control groups, silibinin induced ICD in CT26 and B16F10 cells and significantly enhanced the induction of this type of cell death by doxorubicin, and these changes were allied with substantial increases in the level of damage-associated molecular patterns (DAMPs) including CRT, HSP70, and HMGB1. Furthermore, conditioned media from cancer cells exposed to silibinin and doxorubicin was found to stimulate IL-12 secretion in dendritic cells (DCs), suggesting the link of this treatment with the induction of Th1 response. Silibinin did not augment the ICD response induced by OXP. Conclusion: Our findings showed that silibinin can induce ICD and it potentiates the induction of this type of cell death induced by chemotherapy in cancer cells., (© 2023 The Author(s).)

Purpose: To assess contrast sensitivity in clear and colored soft contact lenses under different lighting conditions., Methods: This study was performed on 34 medical students. Visual acuity was measured using a tumbling E chart at a distance of 6 m, and contrast sensitivity was determined by Pelli Robson chart at a distance of 1 m. These tests were repeated in mesopic (3 lux) and glare (2000 lux) conditions. Then, a clear contact lens was applied to one eye and a colored contact lens was applied to the other. After 2 hr, visual acuity and contrast sensitivity were measured for each individual. The results were compared with and without contact lenses under normal, mesopic, and glare conditions., Results: The mean refractive error was 0.44 ± 0.20 diopters. Repeated measures ANOVA showed a decline in contrast sensitivity with colored and clear contact lenses as compared to no-lens condition ( P < 0.001). Additionally, lighting conditions had a significant impact on contrast sensitivity ( P < 0.001); contrast sensitivity was lower in mesopic and glare conditions than under normal lighting condition., Conclusion: In addition to the drop in contrast sensitivity under unusual lighting conditions (e.g., glare and mesopic), wearing soft contact lenses can further reduce contrast sensitivity in different lighting conditions. Therefore, people who wear contact lenses should be aware of this reduction in visual performance in conditions like driving at night or in the fog., Competing Interests: The authors declare that they have no conflict of interest., (Copyright © 2021 Mahjoob et al.)

Purpose: To determine the distribution of keratometry values in a wide age range of 6-90 years., Methods: In this cross-sectional study, samples were selected from two villages in Iran using multi-stage random cluster sampling. After completing optometry and ophthalmic examinations for all cases, corneal imaging was done using Pentacam, and keratometry values were determined., Results: Of the 3851 selected people, 3314 people participated in the study, and after applying the exclusion criteria, analyses were done on data from 2672 people. Mean age of the participants was 36.30 ± 18.51 years (from 6 to 90 years). Mean keratometry (mean-K) in flat and steep meridians was 42.98 (42.9-43.06) diopters (D) and 43.98 (43.91-44.07) D, respectively. Average of mean-K was 43.48 (43.41-43.56) D. Mean-K increased linearly up to the age of 70 years, and the cornea became slightly flat afterwards (coefficient = 0.01; P < 0.001). Mean-K was significantly higher in females ( P < 0.001). Myopic cases had the highest mean-K ( P < 0.001). The correlation of mean-K with age, gender, central corneal thickness, anterior chamber depth, pupil diameter, and spherical equivalent was investigated in a multiple regression model. Only older age and female gender showed a statistically significant association with mean-K. Overall, 31.62% (29.14-34.09) of the sample in this study had at least 1.0 D of corneal astigmatism., Conclusions: This is one of the few studies worldwide that demonstrates changes in keratometry in a wide age range from childhood to old age. Results indicated that age and gender are variables associated with keratometry., Competing Interests: There are no conflicts of interest., (Copyright: © 2021 Journal of Current Ophthalmology.)

Purpose: To determine the distribution of keratoconus indices in a 5-93-year-old healthy eyes of a rural population in Iran., Methods: In this cross-sectional study, multi-stage cluster sampling was applied to select subjects from two villages in the north and southwest of Iran. After obtaining informed consent, all subjects underwent ophthalmologic and optometric examinations. Corneal imaging by the Pentacam was done in subjects above 5 years between 9 a.m. and 2 p.m., at least 3 h after wakeup. All subjects who had abnormal keratoconus indices were excluded. Our main outcome was keratometry-flat (K f ), keratometry-steep (K s ), keratoconus index (KI), and central keratoconus index (CKI)., Results: The mean ± standard deviation of K f , K s , KI, and CKI was 43.12 ± 1.74, 44.25 ± 1.65, 1.02 ± 0.02, and 1.01 ± 0.01, respectively. According to multiple linear regression analysis, the mean index surface variance (ISV) (b: -1.367, P < 0.001), index vertical asymmetry (IVA) (b: -0.012, P < 0.001), KI (b: -0.011, P < 0.001), CKI (b: -0.001, P < 0.001), index height asymmetry (IHA) (b: -0.491, P: 0.005), and index height decentration (IHD) (b: -0.001, P < 0.001) were lower in men compared to women. Moreover, age had an indirect association with ISV (b: -0.030, P < 0.001) and average pachymetric progression index (RPI&#95;avg) (b: -0.001, P < 0.001), and a direct association with KI, CKI, and IHA. Spherical equivalence had an indirect association with KI (b: -0.001, P < 0.001) and RPI&#95;avg (b: -0.004, P < 0.001) and a direct association with CKI (b: 0.001, P < 0.001). Among all variables, sex had the greatest impact on ISV, IVA, KI, IHA, IHD, and minimum sagittal curvature., Conclusions: The Keratoconus indices of our study were similar to other studies. Although age, living place, and type of refractive error were associated with some indices, sex was the strongest determinant of Keratoconus indices in a population of healthy eyes., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 Journal of Current Ophthalmology.)

Purpose: To determine the distribution of residual and corneal astigmatism (CA) in children aged 6-18 years and their relationship with age, sex, spherical equivalent, and biometric parameters., Methods: In this cross-sectional study, multi-stage stratified cluster sampling was done to select students from Dezful, a city in Southwestern Iran. Examinations included the measurement of visual acuity with and without optical correction, refraction with and without cycloplegia, and biometry using the Biograph (Lenstar, Germany). The main outcomes in this report were corneal and residual astigmatism. The CA was measured by Biograph (difference between k1 and k2), and residual astigmatism was calculated using Alpine method. The power vector method was applied to analyze the data of astigmatism., Results: Of 864 students that were selected, 683 (79.1%) participated in the study. The mean residual and CA were -0.84 diopter (D) and -0.85 D, respectively. According to the results of J0 and J45 vectors, residual astigmatism was -0.33 D and 0.04 D, and CA was 0.38 D and 0.01 D, respectively. With-the-rule (WTR), against-the-rule (ATR), and oblique astigmatism were seen in 3.4%, 66.8%, and 4.5% of the children with residual astigmatism and 67.94%, 1.3%, and 1.5% of the children with CA. Residual astigmatism decreased with an increase in spherical refractive error, whereas CA increased with an increase in spherical refractive error., Conclusion: The results of the present study showed a high prevalence and amount of residual astigmatism with ATR pattern among the 6-18-year-old population and the compensatory effect of this type of astigmatism on CA that mostly followed a WTR pattern., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 Journal of Current Ophthalmology.)

Purpose: To review current non-surgical management methods of intermittent exotropia (IXT) which is one of the most common types of childhood-onset exotropia., Methods: A search strategy was developed using a combination of the words IXT, divergence excess, non-surgical management, observation, overcorrecting minus lens therapy, patch/occlusion therapy, orthoptics/binocular vision therapy, and prism therapy to identify all articles in four electronic databases (PubMed, Web of Science, Google Scholar, and Scopus). To find more articles and to ensure that the databases were thoroughly searched, the reference lists of the selected articles were also reviewed from inception to June 2018 with no restrictions and filters., Results: IXT is treated when binocular vision is impaired, or the patient is symptomatic. There are different surgical and non-surgical management strategies. Non-surgical treatment of IXT includes patch therapy, prism therapy, orthoptic sessions, and overcorrecting minus lens therapy. The objective of these treatments is to reduce the symptoms and the frequency of manifest deviation by decreasing the angle of deviation or enhancing the ability to control it., Conclusions: Evidence of the efficacy of non-surgical management options for IXT is not compelling. More comprehensive randomized controlled trial studies are required to evaluate the effectiveness of these procedures and detect the most effective strategy., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 Journal of Current Ophthalmology.)

Objective: This study was conducted to evaluate the level of agreement in keratometry measurements between a rotating Scheimpflug imaging-based system (Pentacam) and a handheld auto-refractokeratometer (handheld NIDEK ARK-30)., Method: This analytical cross-sectional study was conducted in the right eyes of 579 subjects. Keratometry measurements were conducted with the Pentacam and the handheld NIDEK ARK-30 systems. The SPSS Software version 22 and MedCalc V3 were applied to estimate descriptive statistics using paired t-test, Pearson correlation coefficient, 95% limits of agreement (LoA), and Bland-Altman plot., Results: In the total sample, the inter-device difference in the mean flat and steep keratometry values was -0.266 diopter (D) (P-value<0.001) and 0.052D (P-value=0.093), respectively. There was a significant difference in mean flat keratometry between the two devices in all groups of refractive errors (paired difference <0.5D and P-value<0.001). The difference in mean steep keratometry was significant only in myopic subjects (P-value=0.046). The 95% LoA between the two devices measurements was 2.51D, 3.98D, and 6.37D for flat keratometry and 2.6D, 3.2D, and 3.9D for steep keratometry in emmetropic, myopic, and hyperopic subjects, respectively., Conclusion: Our study showed relatively wide limits of agreement between handheld NIDEK ARK-30 and Pentacam; therefore, these devices cannot be used interchangeably for measuring corneal curvature., (Copyright © 2019 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.)

Purpose: To compare contrast sensitivity (CS) in multi-transfused β-thalassemia patients who received deferoxamine with those who received Osveral., Methods: In this cross sectional study a total of 60 β-thalassemia patients (30 used deferoxamine and 30 used deferasirox) were regarded as case group and 30 age and sex matched healthy subjects were selected as control group. All subjects had a set of examinations including refraction, visual acuity, Biomicroscopy, ophthalmoscopy and CS. Contrast threshold was assessed with the use of Freiberg visual acuity and contrast test under the mesopic light condition for three frequencies; 1, 5, 15cpd. All data analysis was performed using SPSS, version 17., Results: In visual acuity tests, thalassemic patients did not have any problem. Contrast threshold was higher in thalassemic patients who infuse deferoxamine (1.87±0.63, 1.46±0.81, and 2.96±1.68 in 1, 5, and 15cpd, respectively) than that of those who intake deferasirox (1.74±0.80 (P=0.743), 0.99±0.74 (P=0.047), and 2.42±1.36 (P=0.321) for 1, 5, and 15cpd, respectively), and also than healthy patients (1.33±0.58 (P=0.009), 0.95±0.68 (P=0.022), and 2.24±1.23 (P=0.135) for 1, 5, and 15cpd, respectively). Comparing those who used deferasirox with healthy subjects, contrast threshold was higher in deferasirox group at all special frequencies (P>0.05). No significant relationship was observed between CS values and duration of transfusion, serum ferritin concentration and dose of chelation therapy (P>0.05)., Conclusions: CS tests can detect visual disturbance in thalassemic patients before the impairment of visual acuity. It is suggested that CS tests be included in their regular eye examination., (Copyright © 2018 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.)

Purpose: To determine the agreement and validity of keratometric measurements in children with the Nidek ARK-510A auto-refractokeratometer compared to rotating Scheimpflug imaging with Pentacam and biograph with Lenstar LS 900., Methods: This study was conducted on 5620 schoolchildren aged 6-12 years in Shahroud, Iran. Minimum and maximum keratometry values and corneal astigmatism magnitude were compared by calculation of Paired difference, interclass correlation coefficient, and 95% limits of agreement (LoA) between devices., Results: After applying the exclusion criteria, 4215 right eyes were enrolled into the study. Mean minimum keratometry with Nidek ARK-510A, Pentacam, and Lenstar was 43.13±1.51, 43.14±1.48, and 42.87±1.46 diopters (D), respectively, and mean maximum keratometry was 43.97±1.59, 44.00±1.56, and 43.75±1.54D, respectively. Nidek ARK-510A overestimated minimum and maximum keratometry by 0.25±0.37 and 0.22±0.41, respectively, compared to Penatcam. The LoA between Nidek ARK-510A and Pentacam for minimum and maximum keratometry measurements were -0.98 to 0.47D and -1.02 to 0.57D, respectively. The LoA between Nidek ARK-510A and Lenstar for minimum and maximum keratometry measurements were -0.70 to 0.72D and -0.79 to 0.85D, respectively. The agreement between devices was best in emmetropes, worst in hyperopes. For astigmatic vector components, the agreements between devices were poor but best agreement was between Nidek ARK-510A and Pentacam., Conclusions: Keratometry measurement with Nidek ARK-510A was not significantly different from Pentacam and Lenstar, and this device can be used in screening programs in emmetropes., (Copyright © 2019 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.)

Purpose: The aim of this study was to determine the distribution of corneal eccentricity (E-value) in a normal population and to examine related factors., Methods: In this cross-sectional study, two villages were selected in Iran using multistage cluster sampling. Selected persons were invited to have a comprehensive eye examination. Examinations in each village were performed at a specific location under standard conditions. After testing for vision and refraction and conducting the slit-lamp exam, E-value was measured with Pentacam., Results: Of the 3851 selected individuals, 3314 participated in the study. After applying the exclusion criteria, data from 2610 subjects was used in the analysis for this report. Mean E-value was 0.53 [95% confidence interval (CI): 0.52 to 0.54]. E-value was not significantly different between males and females. Mean E-value reduced with age from 0.60 in subjects aged 6-20 years to 0.47 in subjects older than 70 years. The hyperopic group of participants had significantly lower E-value than myopic and emmetropic ones ( P  < 0.001). The relationship of E-value with age, gender, and other anterior segment variables and spherical equivalent was examined in a multiple linear regression model. In multiple linear regression model, age (coef = -0.003), spherical equivalent refraction (coef = -0.005), pupil diameter (coef = 0.018), anterior chamber volume (coef = -0.001), and anterior chamber angle (coef = 0.003) significantly correlated with E-value., Conclusions: The results of this study showed that the cornea in normal populations is prolate, and the degree of prolateness varies by age, such that older age is associated with a less prolate cornea. This study showed that factors such as age and refractive errors and anterior chamber indices influence the E-value.

Purpose: This study was performed to investigate whether occupationally related color vision deficiency can occur from welding., Methods: A total of 50 male welders, who had been working as welders for at least 4 years, were randomly selected as case group, and 50 age matched non-welder men, who lived in the same area, were regarded as control group. Color vision was assessed using the Lanthony desatured panel D-15 test. The test was performed under the daylight fluorescent lamp with a spectral distribution of energy with a color temperature of 6500K and a color rendering index of 94 that provided 1000lx on the work plane. The test was carried out monocularly and no time limit was imposed. All data analysis were performed using SPSS, version 22., Results: The prevalence of dyschromatopsia among welders was 15% which was statistically higher than that of nonwelder group (2%) (p=0.001). Among welders with dyschromatopsia, color vision deficiency in 72.7% of cases was monocular. There was positive relationship between the employment length and color vision loss (p=0.04). Similarly, a significant correlation was found between the prevalence of color vision deficiency and average working hours of welding a day (p=0.025)., Conclusions: Chronic exposure to welding light may cause color vision deficiency. The damage depends on the exposure duration and the length of their employment as welders., (Copyright © 2016 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.)

Purpose: To determine the prevalence of uncorrected refractive errors, need for spectacles, and the determinants of unmet need in underserved rural areas of Iran., Methods: In a cross-sectional study, multistage cluster sampling was done in 2 underserved rural areas of Iran. Then, all subjects underwent vision testing and ophthalmic examinations including the measurement of uncorrected visual acuity (UCVA), best corrected visual acuity, visual acuity with current spectacles, auto-refraction, retinoscopy, and subjective refraction. Need for spectacles was defined as UCVA worse than 20/40 in the better eye that could be corrected to better than 20/40 with suitable spectacles., Results: Of the 3851 selected individuals, 3314 participated in the study. Among participants, 18.94% [95% confidence intervals (CI): 13.48-24.39] needed spectacles and 11.23% (95% CI: 7.57-14.89) had an unmet need. The prevalence of need for spectacles was 46.8% and 23.8% in myopic and hyperopic participants, respectively. The prevalence of unmet need was 27% in myopic, 15.8% in hyperopic, and 25.46% in astigmatic participants. Multiple logistic regression showed that education and type of refractive errors were associated with uncorrected refractive errors; the odds of uncorrected refractive errors were highest in illiterate participants, and the odds of unmet need were 12.13, 5.1, and 4.92 times higher in myopic, hyperopic and astigmatic participants as compared with emmetropic individuals., Conclusion: The prevalence of uncorrected refractive errors was rather high in our study. Since rural areas have less access to health care facilities, special attention to the correction of refractive errors in these areas, especially with inexpensive methods like spectacles, can prevent a major proportion of visual impairment.

Purpose: To evaluate tear film stability and optical aberrations in eyes wearing plano Lotrafilcon B contact lenses (CL)., Methods: Tear Deformation Time (TDT) and aberrometric parameters were assessed in 86 normal emmetropic eyes before and 6 h after wearing CL., Result: A statistically significant decrease in TDT and increase in root mean square (RMS) values of higher order aberrations (HOA) were revealed 6 h after CL insertion (both P < 0.001). The low order aberrations (LOA) RMS values measured with CL were higher than those in naked eyes, but the difference was not statistically significant. None of individual Zernike polynomials showed any significant alteration., Conclusion: Our findings indicated that the Lotrafilcon B contact lens affects HOA more than LOA. The tear film was less stable after wearing CL.

Aims: The aim of this study was to assess ocular changes in thalassemia patients who have received multiple transfusions and chelate binding therapy in order to avoid iron accumulation., Settings and Design: A cross-sectional study., Subjects and Methods: A total of 54 thalassemia major patients were selected as case group, and 54 age- and sex-matched healthy subjects were regarded as a control group. Ocular examination included visual acuity, refraction testing, slit lamp examination, funduscopy, tonometry, perimetry, tear break-up time test, and color vision testing were performed for all the participants. We computed the frequency and duration of blood transfusion, the mean serum ferritin level, pretransfusion hemoglobin concentration, and type, duration, and daily dose of chelation therapy for thalassemia patients based on their records., Statistical Analysis Used: All data analysis was performed using SPSS, version 19., Results: All the thalassemic patients were asymptomatic, but abnormal ocular findings (dry eye (33.3%), cataract (10.2%), retinal pigment epithelium degeneration (16.7%), color vision deficiency (3.7%), and visual field defects (33.7%)) were seen in 68.5% of thalassemic group. The prevalence of ocular abnormalities in normal group was 19.4%, which was significantly lower than that in thalassemia patients (P = 0.000). No significant correlation was found between ocular abnormalities and mean serum ferritin level (P = 0.627) and mean hemoglobin concentration (P = 0.143). Correlation of number of blood transfusion with the presence of ocular abnormalities was found to be statistically significant (P = 0.005)., Conclusions: As life expectancy for beta-thalassemia patients extends, regular ophthalmological evaluation to detect early changes in their ocular system is recommended.

Context: Sunglasses should follow minimum requirements to sufficiently protect eyes. It is not known whether all items obtainable from the market are appropriately designed., Aims: To compare ultraviolet (UV)-protective properties of commercially available sunglasses obtained from authorized and unauthorized Iranian sellers. Settings and Study Design: An analytic-descriptive study performed in a metropolitan area (Tehran)., Materials and Methods: Using a UV-visible standard spectrophotometer, the percentage transmittance was scanned between 280 and 400 nm in 348 pairs of nonprescription sunglasses (price range: 20-80 US$) obtained anonymously and randomly from authorized (permitted by the Ministry of Health, 189 pairs) and unauthorized (159 pairs) sellers in the Iranian capital city, Tehran. The Australian/New Zealand Standard (AS/NZS) and the American National Standards Institute [ANSI] standards were followed., Statistical Analysis: Chi-square test, independent samples t-test or Mann-Whitney U-test. Results UV-protective properties of the sunglasses obtained from authorized sellers complied with AS/NZS and ANSI guidelines in 92.6% and 95.2% of items, respectively. The corresponding rates for sunglasses obtained from unauthorized sellers were 0% and 8.2%, respectively (P < 0.001 for both). The rate of defective polarizing capability of lenses was 27.4% in sunglasses obtained from authorized sellers versus 90.4% in sunglasses obtained from unauthorized sellers (P < 0.001). Neither brand nor price played significant contributions to UV protection/lens polarizing capability of sunglasses obtained from authorized sellers., Conclusions: Sunglasses provided by unauthorized sellers are alarmingly unreliable and could be potentially hazardous for the eye. Brand and price do not guarantee optimal protection against UV radiation or polarizing performance of the lens.