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Purpose: To evaluate the risk factors associated with contamination of lens cases in a group of orthokeratology (ortho-k) lens wearers.Method: Ortho-k patients attending the Contact Lens Clinic of the Hospital were required to complete a checklist about their routine daily care and handling of lens cases. Their cases were then collected for analysis. Contamination was evaluated by determining the optical density (OD) of crystal violet stained biofilm present in the cases. OD values were divided into three groups, lower, middle, and upper tertiles, and associations between risk factors were determined by multivariate analysis.Results: A total of 194 subjects were recruited. Twenty-five subjects used cylindrical lens cases (CC), 98 flat cases with ridges (FCR), and 71 flat cases without ridges (FC). FCRs were the most heavily contaminated and CC showed least contamination (FCR > FC, OR 2.16, CI 1.11-4.18, p =  0.023; FCR > CC, OR 8.86, CI 2.97-26.44, p <0.001; FC > CC, OR 2.33, CI 1.35-12.45, p =  0.013). Replacing lens cases monthly significantly reduced the risk of high contamination (OR 0.013, CI 0.06-0.30, p <  0.001), compared to those used for three months. Cases that were not rinsed (OR 3.44, CI 1.50-7.86, p =  0.003) or rinsed by other methods (OR 4.07, CI 1.67-9.92, p =  0.002) had significantly more contamination, compared to those rinsed with multipurpose solution. Lens cases, which were not dried (OR 11.36, CI 2.06-62.93, p =  0.005) or air-dried (OR 8.71, CI 1.16-65.56, p =  0.036), showed more contamination compared to those wiped with tissue daily.Conclusion: Case design (cylindrical), monthly replacement, daily rinsing with MPS, and wiping with tissue daily can effectively reduce biofilm formation in contact lens cases. [ABSTRACT FROM AUTHOR]

Cognition is very important in our daily life. However, amblyopia has abnormal visual cognition. Physiological changes of the brain during processes of cognition could be reflected with ERPs. So the purpose of this study was to investigate the speed and the capacity of resource allocation in visual cognitive processing in orientation discrimination task during monocular and binocular viewing conditions of amblyopia and normal control as well as the corresponding eyes of the two groups with ERPs. We also sought to investigate whether the speed and the capacity of resource allocation in visual cognitive processing vary with target stimuli at different spatial frequencies (3, 6 and 9 cpd) in amblyopia and normal control as well as between the corresponding eyes of the two groups. Fifteen mild to moderate anisometropic amblyopes and ten normal controls were recruited. Three-stimulus oddball paradigms of three different spatial frequency orientation discrimination tasks were used in monocular and binocular conditions in amblyopes and normal controls to elicit event-related potentials (ERPs). Accuracy (ACC), reaction time (RT), the latency of novelty P300 and P3b, and the amplitude of novelty P300 and P3b were measured. Results showed that RT was longer in the amblyopic eye than in both eyes of amblyopia and non-dominant eye in control. Novelty P300 amplitude was largest in the amblyopic eye, followed by the fellow eye, and smallest in both eyes of amblyopia. Novelty P300 amplitude was larger in the amblyopic eye than non-dominant eye and was larger in fellow eye than dominant eye. P3b latency was longer in the amblyopic eye than in the fellow eye, both eyes of amblyopia and non-dominant eye of control. P3b latency was not associated with RT in amblyopia. Neural responses of the amblyopic eye are abnormal at the middle and late stages of cognitive processing, indicating that the amblyopic eye needs to spend more time or integrate more resources to process the same visual task. Fellow eye and both eyes in amblyopia are slightly different from the dominant eye and both eyes in normal control at the middle and late stages of cognitive processing. Meanwhile, abnormal extents of amblyopic eye do not vary with three different spatial frequencies used in our study. [ABSTRACT FROM AUTHOR]

Aims: To assess diabetic retinopathy (DR) prevalence between elderly onset and younger onset diabetes with similar diabetes duration and evaluate the association between DR prevalence and serum insulin-like growth factor 1 (IGF-1) levels.Methods: A total of 1787 patients with diabetes were enrolled between January 2010 and November 2015. Fundoscopy examination was performed. Patients were divided into three groups by age of diagnosis (<45, 45-64, and ⩾65years) for the analysis of the prevalence of DR. Among them, 150 patients underwent serum IGF-1 measurement. The serum IGF-1 level was compared between patients <65years and ⩾65years.Results: Among 1787 patients, 779 (43.6%) had DR, in which proliferative DR (PDR) 229 (12.8%) patients. For similar diabetes duration, DR prevalence was lower in elderly onset patients. Patients ⩾65years at diagnosis had significantly lowest PDR prevalence of the three groups for similar diabetes duration. IGF-1 levels were lower in patients ⩾65years than in patients <65years (104.89±49.91ng/mL vs. 141.73±62.04ng/mL, P<0.001).Conclusions: Elderly onset patients with diabetes have lower prevalence of PDR than those younger onset patients for similar diabetes duration, which may relate with lower serum IGF-1 levels in older patients. Thus, less stringent glycemic control in older onset patients with diabetes may not increase the prevalence of PDR. [ABSTRACT FROM AUTHOR]

Autophagy is recognized as a promising therapeutic target for traumatic brain injury (TBI). Crocetin is an aglycone of crocin naturally occurring in saffron and has been found to alleviate brain injury diseases. However, whether crocetin affects autophagy after TBI remains unknown. Therefore, we explore crocetin roles in autophagy after TBI. We used a weight-dropped model to induce TBI in C57BL/6J mice. Neurological severity scoring (NSS) and grip tests were used to evaluate the neurological level of injury. Brain edema, neuronal apoptosis, neuroinflammation and autophagy were detected by measurements of brain water content, TUNEL staining, ELISA kits and western blotting. Crocetin ameliorated neurological dysfunctions and brain edema after TBI. Crocetin reduced neuronal apoptosis and neuroinflammation and enhanced autophagy after TBI. Crocetin alleviates TBI by inhibiting neuronal apoptosis and neuroinflammation and activating autophagy. [ABSTRACT FROM AUTHOR]

The present study aimed to explore temporal frequency discrimination in amblyopia, and the influence of attentional load on amblyopic temporal cognition. Twenty anisometropic amblyopes, 20 strabismic amblyopes and 20 normal subjects were recruited. A flickering disk was used for visual stimuli. A two-alternative, forced-choice staircase paradigm was used to measure the temporal frequency discrimination thresholds of amblyopic eyes, fellow eyes and normal dominant eyes under reference temporal frequencies of 5, 10 and 20 Hz. The just-noticeable differences data were analyzed statistically. In addition, the temporal frequency discrimination thresholds of the subjects were measured under different conditions of attentional load. The changes in temporal frequency discrimination thresholds were compared between amblyopic and normal eyes when attention was loaded. At the reference temporal frequencies of 5 and 10 Hz, temporal thresholds of amblyopic eyes were significantly increased compared with fellow eyes (P<0.05). Regarding strabismic amblyopia, temporal thresholds of fellow eyes were increased compared with normal eyes (P<0.05). However, no correlation was identified between the temporal-frequency discrimination thresholds and the LogMAR visual acuities in amblyopic eyes. In addition, higher attentional load caused greater changes in temporal thresholds in amblyopic eyes, but the situation was not the same for lower attentional load. In conclusion, in the present study a deficit of temporal frequency discrimination in amblyopic eyes and the fellow eyes of strabismic amblyopes was identified. Furthermore, the influence of attentional load on temporal frequency discrimination in amblyopic eyes was increased compared with normal eyes. [ABSTRACT FROM AUTHOR]

To investigate the effects of orthokeratology (ortho -k) lenses with aspheric and spherical base curve designs on corneal refractive power (CRP) and peripheral refraction. Children aged 8 to 12 years with myopia between −0.75 D to −4.00 D, astigmatism ≤1.00 D, and corneal astigmatism ≤1.50 D were randomly assigned to the base curve aspheric (BCA) and base curve spherical (BCS) ortho -k lens groups. CRP was assessed for the central 8 mm cornea along horizontal and vertical meridians, and peripheral refraction was measured at 10°, 20°, and 30° along the nasal and temporal retina. Primary measurements included relative corneal refractive power change (RCRPC) and relative peripheral refraction change (RPRC). The 3-month results of the 33 and 29 subjects (right eye only) in the BCA and BCS groups, respectively, were obtained. Nonsignificant differences were found in the baseline data between the two groups (p > 0.05). At the 3-month follow-up visit, the mean RCRPC in the BCA group (2.08 ± 0.65 D) was significantly greater than that in the BCS group (1.32 ± 0.81 D) (F 1,51 = 25.25, p < 0.001). The BCA group (-1.82 ± 0.65 D) exhibited a larger absolute RPRC than the BCS group (-0.98 ± 0.54 D) (F 1,57 = 33.73, p < 0.001). It was found that the BCA ortho -k lens resulted in a more aspheric treatment zone and a more myopic relative peripheral refraction (RPR) along the horizontal meridian. The more myopic RPR was contributed by a more hyperopic central refraction and a more myopic peripheral refraction in the BCA group. [ABSTRACT FROM AUTHOR]

Purpose: A multi‐level model was used to analyse factors, including environmental factors, affecting the controlling effect of orthokeratology on myopia progression. Methods: A 2‐year prospective study was conducted in the West China Hospital, Sichuan University. Age, sex, height, baseline spherical equivalent refraction, choroidal thickness, axial length and other biometric ocular parameters were collected. Additionally, data on the following environmental factors were obtained: near‐work distance and time, sleep time and time spent outdoors. After the baseline measurements, participants were followed up every 3 months for 2 years of lens wear. The primary outcome measure was axial length elongation over 2 years of orthokeratology. All variables were included in a univariate, three‐level analysis model with inclusion in the final multivariate multi‐level model if statistically significant. Results: Thirty‐three participants (average age 9.73 ± 1.55 years) were included in this study. During the 2‐year period of lens wearing, binocular changes in axial length increased significantly from the ninth month and continued until the end of the follow‐up. Changes in axial length after 2 years of lens wearing were 0.44 ± 0.30 mm and 0.37 ± 0.26 mm in the right and left eyes, respectively (both p < 0.001). Based on the 2‐year multi‐level model, age, sex, baseline spherical equivalent refraction, flatter keratometry meridian and near‐work time influence the effect of orthokeratology. Conclusions: This is the first study to use a multi‐level model to analyse factors, including environmental factors, that affect myopia control using orthokeratology. These results showed that younger age, being female, having lower myopia at baseline, a steeper flattest keratometry meridian and no more than 5 h of near work per day were associated with better myopia control effect using orthokeratology over a 2‐year treatment period. [ABSTRACT FROM AUTHOR]

The structure of the retinal vascular tree can reflect many indicators of ophthalmic health status. Retinal vessel segmentation, an important basis for the quantitative analysis of vascular structure, has been developed over decades. However, in the areas of imaging quality and contrast, there are still vascular ruptures and missed detection by existing methods. Moreover, the problem of false positives caused by existing lesions has not been properly addressed. Inspired by the primary visual cortex of the biological visual system, this paper proposes Anisotropic Perceptive Convolution (APC) and Anisotropic Enhancement Module (AEM) to model visual cortex cells and their orientation selection mechanism, respectively, as well as a novel network named W-shaped Deep Matched Filtering (WS-DMF) having a W-shaped overall framework. In the feature extraction backbone, a DMF based on a multilayer aggregation of APC is designed to enhance vascular features and inhibit the expression of pathological features. In addition, AEMs are embedded into DMF to enhance the orientation and position information of high-dimensional features. Furthermore, in order to enhance the ability of APC for perceiving linear textures (such as blood vessels), an Orientation Anisotropic Loss (OAL) is introduced. Based on experiments on several widely used datasets and several professional vessel segmentation metrics, the proposed method exhibits strong abilities of vessel extraction and lesion inhibition, surpassing many state-of-the-art algorithms. The results indicate the potential value of WS-DMF in clinical practice. The source code is available at https://www.github.com/tyb311/WS-DMF. [Display omitted] • In order to reduce the missed detection of vessels under poor imaging quality, we propose an anisotropic perceptual convolution (APC) layer to highlight the vascular structure by extracting locally linear textures and suppressing isotropic regions. • To reduce the phenomenon of vessel rupture, we propose a deep matched filtering (DMF) backbone based on the aggregation of a multilayer orientation perception convolution, enabling the model to deduce and connect the broken vessels. • Moreover, in order to enhance the anisotropic features (i.e., vessels), we design the Anisotropic Enhancement Modules (AEM) to emphasize the orientation and position of vessels in high-dimensional space. • Qualitative and quantitative experiments on several widely used datasets show that the proposed method has excellent performance. [ABSTRACT FROM AUTHOR]

Purpose The aim was to compare the impact of rigid gas-permeable ( RGP) contact lenses on vision-related quality of life ( VR-QOL) in keratoconic patients with different grades of severity. Methods This comparative study was conducted from December 2012 to September 2013 on 46 patients with bilateral keratoconus. Patients were divided into three groups according to the average of the steep keratometry ( K) readings in the two eyes of each patient. Main outcome measures included binocular visual acuity ( VA), lens wearing time, the 25-item National Eye Institute Visual Function Questionnaire ( NEI-VFQ-25), foreign body ( FB) sensation, comfort and overall satisfaction. Results Patients with severe keratoconus showed significantly reduced wearing time compared with the other two groups (4.8 ± 2.5 hours per day). Regarding the subjective criteria, there was no significant difference on NEI-VFQ-25 scores, foreign body sensation, comfort and overall satisfaction between mild and moderate keratoconus groups but scores in the group with severe keratoconus were significantly lower than the other two groups. Binocular VA strongly correlated with NEI-VFQ-25 scores; however, NEI-VFQ-25 scores had no significant correlations with different disease severities. Conclusions Appropriate correction with RGP lenses contributes to good VR-QOL for keratoconic patients; however, as the disease progresses to a steep keratometric value of more than 52 dioptres (6.50 mm), RGP lenses did not guarantee a relatively good VR-QOL. Other lens options with new designs might bring better life quality for these patients with severe keratoconus. [ABSTRACT FROM AUTHOR]