Development, comparison, and internal validation of prediction models to determine the visual prognosis of patients with open globe injuries using machine learning approaches.

INTRODUCTION: Open globe injuries (OGI) represent a main preventable reason for blindness and visual impairment, particularly in developing countries. The goal of this study is evaluating key variables affecting the prognosis of open globe injuries and validating internally and comparing different machine learning models to estimate final visual acuity. MATERIALS AND METHODS: We reviewed three hundred patients with open globe injuries receiving treatment at Khatam-Al-Anbia Hospital in Iran from 2020 to 2022. Age, sex, type of trauma, initial VA grade, relative afferent pupillary defect (RAPD), zone of trauma, traumatic cataract, traumatic optic neuropathy (TON), intraocular foreign body (IOFB), retinal detachment (RD), endophthalmitis, and ocular trauma score (OTS) grade were the input features. We calculated univariate and multivariate regression models to assess the association of different features with visual acuity (VA) outcomes. We predicted visual acuity using ten supervised machine learning algorithms including multinomial logistic regression (MLR), support vector machines (SVM), K-nearest neighbors (KNN), naïve bayes (NB), decision tree (DT), random forest (RF), bagging (BG), adaptive boosting (ADA), artificial neural networks (ANN), and extreme gradient boosting (XGB). Accuracy, positive predictive value (PPV), recall, F-score, brier score (BS), Matthew correlation coefficient (MCC), receiver operating characteristic (AUC-ROC), and calibration plot were used to assess how well machine learning algorithms performed in predicting the final VA. RESULTS: The artificial neural network (ANN) model had the best accuracy to predict the final VA. The sensitivity, F1 score, PPV, accuracy, and MCC of the ANN model were 0.81, 0.85, 0.89, 0.93, and 0.81, respectively. In addition, the estimated AUC-ROC and AUR-PRC of the ANN model for OGI patients were 0.96 and 0.91, respectively. The brier score and calibration log-loss for the ANN model was 0.201 and 0.232, respectively. CONCLUSION: As classic and ensemble ML models were compared, results shows that the ANN model was the best. As a result, the framework that has been presented may be regarded as a good substitute for predicting the final VA in OGI patients. Excellent predictive accuracy was shown by the open globe injury model developed in this study, which should be helpful to provide clinical advice to patients and making clinical decisions concerning the management of open globe injuries.

Clinical characteristics and management outcome of acute infectious endophthalmitis.

PURPOSE: This study aimed to investigate the demographics, clinical characteristics, and management outcomes of patients with acute infectious endophthalmitis (AIE). METHODS: This retrospective chart review was conducted on all patients admitted with the clinical diagnosis of infectious endophthalmitis from 2017 to 2022. Demographic data, patients' clinical characteristics, the type of acute infectious endophthalmitis (post-operative, post-traumatic, bleb-associated, and endogenous endophthalmitis), the type of surgical procedure in the post-operative cases, the microbiologic analysis results of vitreous samples, therapeutic measures, and visual outcomes of patients were recorded. RESULTS: In this study, 182 participants, including 122 male (67%) and 60 (33%) female, were involved. The mean age of patients was 54.56 ± 21 years, with a range of 1-88 years old. The most prevalent type of AIE was post-operative (59.9%), followed by endogenous (19.2%), post-traumatic (17%), and bleb-associated (3.8%). The most common type of intraocular surgery in the post-operative subgroups of AIE patients was phacoemulsification (57.8%). The median (interquartile range) of the primary and final BCVA of patients was 1.5 (1.35, 1.85) and 0.65 (0.35, 1.35), respectively. Vitreous haziness grade (OR, 2.89; 95% CI, 1.11-5.74; p = 0.009) and the primary VA (OR, 60.34; 95% CI, 2.87-126.8; p = 0.008) revealed statistical significance for final vision loss. CONCLUSION: AIE is a devastating condition with poor visual outcomes, which presents with acute inflammatory signs and symptoms regardless of its type. However, prompt and appropriate treatment leads to visual recovery to a functional level in many patients.

An intelligent decision support system for acute postoperative endophthalmitis: design, development and evaluation of a smartphone application.

BACKGROUND: Today, clinical decision support systems based on artificial intelligence can significantly help physicians in the correct diagnosis and quick rapid treatment of endophthalmitis as the most important cause of blindness in emergency diseases. This study aimed to design, develop, and evaluate an intelligent decision support system for acute postoperative endophthalmitis. METHODS: This study was conducted in 2020-2021 in three phases: analysis, design and development, and evaluation. The user needs and the features of the system were identified through interviews with end users. Data were analyzed using thematic analysis. The list of clinical signs of acute postoperative endophthalmitis was provided to ophthalmologists for prioritization. 4 algorithms support vector machine, decision tree classifier, k-nearest neighbors, and random forest were used in the design of the computing core of the system for disease diagnosis. The acute postoperative endophthalmitis diagnosis application was developed for using by physicians and patients. Based on the data of 60 acute postoperative endophthalmitis patients, 143 acute postoperative endophthalmitis records and 12 non-acute postoperative endophthalmitis records were identified. The learning process of the algorithm was performed on 70% of the data and 30% of the data was used for evaluation. RESULTS: The most important features of the application for physicians were selecting clinical signs and symptoms, predicting diagnosis based on artificial intelligence, physician-patient communication, selecting the appropriate treatment, and easy access to scientific resources. The results of the usability evaluation showed that the application was good with a mean (± SD) score of 7.73 ± 0.53 out of 10. CONCLUSION: A decision support system with accuracy, precision, sensitivity and specificity, negative predictive values, F-measure and area under precision-recall curve 100% was created thanks to widespread participation, the use of clinical specialists' experiences and their awareness of patients' needs, as well as the availability of a comprehensive acute postoperative endophthalmitis clinical dataset.

Acute effects of coffee consumption on the microcirculation of macula and optic nerve head.

Purpose: This study aimed to evaluate the acute changes in retinal vasculature following coffee consumption. Methods: This is an interventional case series. The subjects were 22 healthy young adults. They were asked to rest in a silent room for 15 min; then, their heart rate, blood pressure, and arterial oxygen saturation pressure were measured with a single patient monitoring system. Optical coherence tomography (OCT) and OCT angiography (OCT-A) imaging of the disc and macula were performed for both eyes of the subjects. These measurements were repeated 45 min after drinking a cup of 450 ml of coffee containing a standard dose of 130 mg of caffeine. Macular and optic nerve head neurovasculature changes were assessed. Results: The results of our study did not show a significant change in peripapillary retinal nerve fiber layer thickness and neural structural and vascular parameters of the optic nerve head. Although assessments of macular vasculature showed a significant decrement in superficial (p = 0.01) and deep vessel density (p = 0.05) at parafovea, vessel densities (VDs) at the fovea, and deep capillary plexus at perifovea showed no significant change. Conclusion: Consuming one cup of coffee (150 mg caffeine) statistically changes central foveal thickness and parafoveal blood flow but likely does not have a clinical impact in healthy young adults.

Evaluation of the Effect of Religious Fasting on Retinal Vessel Density and Retinal Thickness Using Optical Coherence Tomography Angiography.

We conducted this study to assess the effect of religious fasting on intraocular pressure (IOP) as well as retinal parameters and retinal thickness during Ramadan using optical coherence tomography angiography (OCTA) performed on a spectral domain device. All the participants ate a pre-dawn meal and drink, and then fasted for at least 15 hours. We assessed a total of 61 eyes from 31 healthy volunteers with a mean age of 32.87 ± 8.07. A significant decrease was found in the median IOP after fasting at 10.00 mmHg in comparison with the pre-fasting value of 12.00 mmHg (p < .0001). Retinal peri-papillary capillary (RPC) whole image, RPC inside disk, and RPC mean values showed significant decreases after fasting (p = .011, .012, and .032 respectively). RPC whole vessel density (VD), RPC inside VD, and RPC VD mean values also showed significant decreases after fasting period (p = .025, <.0001, and .003, respectively). Religious fasting during the warm season could decrease IOP. It could also reduce the blood flow of the retina, specifically the macula, and the retinal peri-papillary VD.

Wide-field choroidal thickness and vascularity index in myopes and emmetropes.

PURPOSE: To study regional variations in choroidal thickness (CT), luminal thickness and stromal thickness of the choroid, and choroidal vascularity index (CVI) in low myopic and emmetropic eyes using wide-field optical coherence tomography (OCT). METHODS: Sixty-nine healthy young adults between 20 and 38 years of age participated in this study, including 40 low myopes (mean ± SD spherical equivalent (MSE) refractive error: -3.00 ± 1.39 D, range: -6.00 to -0.62 D) and 29 emmetropes (MSE: -0.05 ± 0.09 D, range: -0.25 to +0.12 D). Wide-field CT, luminal thickness, stromal thickness and CVI were measured across five eccentricities (fovea, parafovea, perifovea; near-periphery and periphery) and four quadrants (nasal, temporal, inferior and superior), in vertical and horizontal meridians, while controlling for a range of extraneous factors potentially influencing the CT. Custom-written software was used to segment and binarize the OCT images. RESULTS: Wide-field CT, luminal thickness and stromal thickness, averaged across all participants, exhibited significant topographical variation, with the foveal (379 ± 8 µm, 200 ± 4 µm, 179 ± 4 µm, respectively) and peripheral (275 ± 8 µm, 161 ± 4 µm, 114 ± 4 µm, respectively) regions presenting the thickest and thinnest regions (all p < 0.001). Wide-field CVI showed a progressively higher percentage (greater vascularity) with increasing eccentricity from the fovea towards the periphery (p < 0.001). Macular CT and stromal choroidal thickness were significantly thinner in myopes compared to emmetropes (p < 0.05). Myopes (55.7 ± 0.3%) showed a slightly higher CVI compared with emmetropes (54.4 ± 0.4%) (p < 0.05). CONCLUSIONS: Low myopia in young adults was associated with significant choroidal thinning across the macular, but not extramacular regions, with this decrease in choroidal thickness mostly attributed to thinning in the stromal component of the choroid, rather than the luminal (vascular) component.

Effect of antiglaucoma agents on short-term intraocular pressure fluctuations after intravitreal bevacizumab injections.

PURPOSE: To evaluate the effect of prophylactic pressure-lowering medications on intraocular pressure (IOP) spikes after intravitreal injections (IVIs) METHODS: In this randomized double-blind clinical trial, 74 eyes that were candidates for intravitreal anti-vascular endothelial growth factor (VEGF) injection (IVI) (0.05 mL, 1.25 mg of bevacizumab) were enrolled and sorted randomly into five groups, group 1: topical timolol 0.5% (n = 16); group 2: topical brimonidin (n = 15); group 3: oral acetazolamide 250 mg (n = 14); group 4: intravenous mannitol (1.5 gr/kg) (n = 16); group 5: no intraocular pressure-lowering medication (n = 13). Medications were administered 30-60 min prior to injection. None of the patients had history of glaucoma. Intraocular pressure was measured before (baseline), 5 min after (T5), 10 min after (T10), 15 min after (T15) and 30 min after (T30) IVI using Goldmann Tonometer. RESULTS: There was a statistically significant, but relatively weak negative correlation between the amount of vitreous reflux post-IVI intraocular pressure elevation (Spearman's rho = -0.315, p = 0.006). There was no difference of the amount of vitreous reflux (P = 0.196) between study groups. The baseline mean IOP for Groups 1, 2, 3,4 and 5 were 11.19 ± 3.7, 10.07 ± 2.19, 11 ± 2.98, 10.13 ± 3.48 and12.54 ± 2.60 mmHg, respectively. (P = 0.214) There was no difference of peak IOP spike between groups at T5: 37 ± 19.7, 34.80 ± 15.76, 33.43 ± 18.29, 33.56 ± 16.88, 34.92 ± 9.99 mmHg (P = 0.977). There was also no difference of IOP at T10, T15 and T30 between study groups: P = 0.979, P = 0.994 and P = 0.692, respectively. CONCLUSION: Although it is advisable to prevent IOP spikes, our study showed that use of prophylactic pressure-lowering medications with every mechanism of action has no effect in IOP spikes following intravitreal bevacizumab injections in non-glaucomatous eyes. Trial registrationThe study was registered with clinicaltrails.gov (ID# NCT02140450). Trial registration date: 05.09.2014.

Visual prognosis, clinical features, and predisposing factors in non-HIV patients with cytomegalovirus retinitis.

PURPOSE: To study the characteristics and visual outcome of cytomegalovirus retinitis in patients of a tertiary referral ophthalmology center. METHODS: This retrospective cross-sectional study included 16 patients who presented with CMV retinitis between February 2014 and January 2017. Demographics, clinical signs, course of treatment, and visual and anatomical results were analyzed. RESULTS: Twenty five eyes of 16 patients were included. Eleven (68.8%) were females. The mean age was 29.37 ± 17.12 (range 11-73) years. Involvement was bilateral in 9 (56.2%) cases. HIV serology was negative in all patients. Best-corrected visual acuity was 0.57 ± 0.55 logarithm of the minimal angle of resolution (LogMAR) at the time of presentation and decreased to 0.69 ± 0.55 LogMAR on final visit (P = 0.332). None of the patients participating in this study was HIV-positive. CONCLUSION: CMV retinitis is a devastating complication in immunosuppressed. The visual acuity usually decreases despite aggressive appropriate treatment. This observation supports the increasing incidence of CMV infection in non-HIV patients.

Optical Coherence Tomography and Biometry in High Myopia with Tilted Disc.

PURPOSE: The purpose of this study was to compare retinal thickness and biometric parameters between highly myopic eyes with and without tilted optic discs. METHODS: A total of 60 eyes from 60 highly myopic individuals (defined as a mean spherical equivalent refraction of -6.00 D or greater and axial length ≥26 mm) underwent detailed ophthalmic examination. Twenty-one eyes (13 females and 8 males; mean age: 29 ± 7 years) with tilted optic discs were recruited and compared with 39 eyes (23 females and 16 males; mean age: 28 ± 6 years) of control subjects without tilted optic discs using spectral domain optical coherence tomography (OCT) and the Lenstar biometer. Disc ovality was assessed using the ratio of minimum to maximum disc diameter (index of tilt). A ratio of ≤0.80 was considered as a tilted optic disc. RESULTS: There were no significant differences in biometric parameters between two groups. However, myopia in the tilted disc group was significantly greater compared to the non-tilted group (-8.82 ± 1.58 D vs. -7.84 ± 1.22 D, p = 0.01). Comparison of OCT sectoral macular nerve fiber layer measurements between groups showed significant differences in inner ring thicknesses for the nasal (p = 0.01), inferior (p < 0.001), and temporal (p = 0.04) quadrants. A significant difference was also seen in outer ring macular nerve fiber layer thickness for the temporal quadrant (p = 0.03). No significant differences were demonstrated in optic disc peripapillary retinal nerve fiber layer (RNFL) thickness between the two groups. CONCLUSIONS: Mean spherical equivalent refractive error is strongly correlated with optic disc tilt; however, other biometric factors are independent of tilt. Structural examination of the eye using OCT can be employed to differentiate between eyes with tilted optic discs and those with normal discs. Peripapillary RNFL appears to be unaffected by tilted discs.

Effect of oral photochemotherapy (8-methoxypsoralen + UVA) on the electrophysiologic function of retina.

CONTEXT: Since we had observed electroretinographic (ERG) abnormalities in some patients undergoing photochemotherapy with normal eye examination, we decided to investigate the effects of this therapy on retinal function. OBJECTIVE: To investigate the effects of oral photochemotherapy (8-methoxypsoralen + Ultraviolet-A) on electrophysiologic function of retina. MATERIALS AND METHODS: Patients with vitiligo, psoriasis or eczema were enrolled. Patients with any abnormal eye exam or a positive drug or family history for retinal disease were excluded. Baseline standard ERG was provided with the RETIport32 device. The second ERG was performed 6 months after the first and at least 1 week after the last photochemotherapy session (mean number of sessions: 45 ± 11). The outcome measures were changes in rod response, standard combined response, single-flash cone response, 30-Hz flicker (N1-P1) and oscillatory potentials amplitudes. RESULTS: Forty patients were enrolled; 20 of them (mean age: 31.1 ± 12 years) completed the study. The mean rod response b-wave amplitude decreased from 88.9 ± 47.5 to 86.4 ± 36.6 and standard combined response b-wave amplitude decreased from 266.52 to 261.85 µV (p = 0.422 and p = 0.968, respectively) and the standard combined response a-wave amplitude increased from 155.4 ± 40.0 at baseline to 165.1 ± 48.4 in the follow-up ERG (p = 0.092). The mean single-flash cone response a-wave amplitude decreased insignificantly in the follow-up ERG trace (34.5 ± 13.7 and 29 ± 15.4, respectively, p = 0.242). The mean single-flash cone response b-wave amplitude showed an insignificant increase (p = 0.087). The amplitudes of 30-Hz flicker wave and oscillatory potentials did not change significantly in the follow-up ERG (p = 0.551 and p = 0.739, respectively). CONCLUSION: Since no significant change in ERG traces was observed, oral photochemotherapy seems safe for retinal electrophysiologic function.

Sulfur Mustard Exposure and Non-Ischemic Central Retinal Vein Occlusion.

A 41-year-old man was referred with a complaint of visual loss in his left eye and his best corrected visual acuity was 20/80. Slit lamp examination showed arborizing conjunctival vessels and dry eye. Fundus examination and fluorescein angiography revealed a non-ischemic central retinal vein occlusion. Cardiovascular, rheumatologic, and hematologic work up showed no abnormal findings. An ascertained history of exposure to sulfur mustard during the Iran-Iraq war was documented in his medical history. Four sessions of intravitreal bevacizumab injections were done as needed. After two-year follow-up, visual acuity in his left eye improved to 20/25 and macular edema was resolved without any need for further interventions. We conclude that sulfur mustard gas exposure may be considered as a predisposing factor for central retinal vein occlusion, as was found in our patient (an Iranian war veteran) by excluding all yet known etiologies and predisposing factors.

Electrophysiologic evaluation of retinal function in patients with psoriasis and vitiligo.

PURPOSE: To investigate the relation between psoriasis and vitiligo with the electrophysiologic function of the retinal photoreceptors. METHODS: Patients with psoriasis or vitiligo referred for PUVA therapy were enrolled. Complete eye examination was performed. Patients with any drug or familial history or abnormal eye examination that might affect the retinal function were excluded. Standardized full-field electroretinogram (ERG) elicited with Ganzfeld stimuli using the commercial ERG system (Retiport32; Roland Consult) according to International Society for Clinical Electrophysiology of Vision guidelines was performed. The outcome measures were the difference between the mean rod response, standard combined response, single-flash cone response and 30-Hz flicker wave amplitudes of the patients and normal population. RESULTS: Seventy-six eyes of 38 patients (vitiligo: 21; psoriasis: 17) and 40 eyes of 20 normal subjects were enrolled in this study. The mean age of patients was 31.3 ± 11.3 years (range 16-54 years). Twenty-two patients (58 %) were female. The mean rod response b-wave, standard combined a- and b-waves, single-flash cone response b-wave and the 30-Hz flicker (N1-P1) amplitudes were significantly lower than the normal population in the same range of age as the study group. There was no significant difference between the patients with vitiligo and those with psoriasis in all wave amplitudes (P = 0.094). CONCLUSION: This study showed that overall retinal electrophysiologic function in patients with vitiligo or psoriasis is significantly impaired compared with normal population, independent of age and sex.

A simple method for detecting vitrectomy infusion line position in hazy media, in case of poor visualization.

PURPOSE: To introduce a simple and practical method for detecting vitrectomy infusion line position in a hazy media. METHODS: The position of the infusion cannula was evaluated before and during vitrectomy in 17 eyes of 17 patients with hazy media. This procedure was performed by using the light pipe inserted partially into the cannula and determining the color of transmitted light into the vitreous cavity. Dark red or brownish color was considered as suprachoroidal placement and bright whitish color as the correct position of the cannula tip. RESULTS: In 13 patients, the position of the cannula was considered as a precise position by using the aforementioned method at the beginning of the operation, and vitrectomy was performed without any infusion line-related complications. In two cases, the incorrect placement of the infusion cannula was confirmed with this technique, and the cannula was reinserted and repositioned. In two cases, secondary slippage of the cannula in suprachoroidal space was detected by using this method during vitrectomy, and another cannula was tried in another position. CONCLUSION: Using the color of light pipe inserted partially into the cannula is a safe and simple method for evaluating the position of the infusion line in the eye.

Evaluating the Efficacy and Safety of Aflibercept Biosimilar (P041) Compared with Originator Product in Patients with Neovascular Age-Related Macular Degeneration.

OBJECTIVE: To assess the noninferiority of biosimilar aflibercept (P041, CinnaGen) to the originator aflibercept (AFL, Regeneron) in terms of efficacy, safety, and immunogenicity. DESIGN: This was a phase Ш, 52-week, multicenter, randomized, double-masked, and active control trial involving eyes in a 1:1 ratio. SUBJECTS: Patients with active subfoveal choroidal neovascularization secondary to age-related macular degeneration randomized into the 2 groups of P041 and AFL. METHODS: Patients received an injection of aflibercept every 4 weeks for 3 doses, followed by administration every 8 weeks up to week 48. MAIN OUTCOME MEASURES: The primary outcome was the noninferiority analysis of eyes maintaining vision at week 52. Secondary outcomes included the changes in visual acuity and retinal thickness, safety evaluation, and immunogenicity during the study. RESULTS: In total, 168 eyes of 168 patients were included. At week 52, the proportion of patients maintaining vision was 94.44% in the P041 group compared with 94.52% in the AFL group. The 95% confidence interval (CI) for the difference of maintaining vision from baseline did not exceed the predefined noninferiority margin of 10% (difference, -0.0008; 95% CI, -0.074 to 0.074; P = 0.98). Secondary outcomes indicated similar results in both arms (all P > 0.05). Safety measured outcomes and immunogenicity were similar between the 2 study groups. CONCLUSIONS: Biosimilar aflibercept was noninferior to AFL in eyes with neovascular age-related macular degeneration. Other efficacy and safety findings also indicated the similarity of 2 products. FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Image calibration in choroidal vascularity index measurement.

Choroid is a tissue with a very high blood flow which is a metabolic supporter of the retina. Recently, the study of choroidal blood flow in ocular and systemic disorders is a hot topic in scientific research. With the advent of enhanced depth imaging OCT (EDI-OCT), it is possible to measure the entire choroidal thickness. The choroidal vascularity index (CVI) is a relatively new index in studying choroidal hemodynamics. However, the CVI measurement needs image processing. Image calibration is a necessary step before any image processing with software such as ImageJ.

Incidence of Retinopathy of Prematurity in Neonates with Neonatal Sepsis.

BACKGROUND: One of the most important complications of premature birth is retinopathy of prematurity (ROP). Sepsis may increase the incidence of this complication. The aim of this study is to compare the incidence of ROP in neonates with and without sepsis. METHODS: In a retrospective case-control study, preterm infants admitted to the neonatal intensive care unit (NICU) of Ghaem hospital from 2014 to 2022 were examined. The case group consisted of 155 preterm infants with definite sepsis (positive blood culture and clinical signs of sepsis) and the control group included 145 preterm infants without sepsis whose maternal and neonatal characteristics were collected; they were examined by a retinologist and evaluated for ROP at 32 weeks or four weeks after birth. Finally, we used the chi-square and the t test to compare the two groups. RESULTS: Out of 155 preterm infants with sepsis, 70% and out of 145 preterm infants without sepsis, 58% had ROP (P=0.023). Also, low birth weight, low initial Apgar score and low 5-minute Apgar score were significantly associated with ROP (P<0.05). CONCLUSION: Based on the results of this study, sepsis is a serious risk factor for ROP. We can reduce its incidence and complication by preventing sepsis in premature infants.

Subfoveal choroidal thickness following pars plana vitrectomy in tractional diabetic macular edema.

PURPOSE: To evaluate changes in subfoveal choroidal thickness (SCT) in cases of tractional diabetic macular edema (DME) after pars plana vitrectomy (PPV). METHODS: This prospective study included 31 eyes of 31 patients who underwent PPV for the management of tractional DME. Best-corrected visual acuity (BCVA), SCT, and central macular thickness (CMT) were measured before the operation, as well as one, three, and six months following the surgery in the operated eyes and at baseline, as well as six months in the fellow eyes. RESULTS: The SCT decline in eyes with tractional DME was statistically significant six months postoperatively (P = 0.009). A statistically significant decline was observed in the CMT values one, three, and six months postoperatively in eyes with tractional DME (P = 0.02, P < 0.001, and P < 0.001, respectively). There was a statistically significant improvement in the visual acuity of the affected eyes three (P = 0.047) and six months (P = 0.017) postoperatively. CONCLUSION: After PPV for the treatment of tractional DME, a statistically significant decrease in the CMT values is detectable from the first month after surgery, followed by the improvement of BCVA from the third month. It is worth mentioning that a decrease was found in the SCT six months postoperatively.

Seasonal variations in anterior segment angle parameters in myopes and emmetropes.

CLINICAL RELEVANCE: Seasonal variations are known to occur in a range of ocular parameters and in conditions including refractive error and glaucoma. It is of clinical importance to know if seasonal changes also occur in anterior segment angle parameters, given that they can influence these conditions. BACKGROUND: The study aimed to examine the seasonal variations in anterior segment angle parameters in healthy young adults. METHODS: Twenty-three emmetropic participants with a mean age of 26.17 ± 4.43 years and 22 myopic participants with a mean age of 27.27 ± 4.47 years completed four seasons of data collection. Anterior segment angle parameters were measured using swept-source anterior segment optical coherence tomography. Intraocular pressure (IOP) and objective refraction were also measured. Repeated-measures analysis of variance was used to determine the effect of season and refractive error on the various ocular parameters. RESULTS: A significant main effect of season was found for the majority of anterior segment angle parameters, including the angle opening distance at 500 and 750 µm from the scleral spur (p = 0.02, p = 0.006, respectively), angle recess area at 500 and 750 µm from the scleral spur (both p = 0.002), and trabecular iris space area at 500 and 750 µm from the scleral (p = 0.02, p = 0.008, respectively). However, measures of anterior chamber depth and trabecular iris angle did not exhibit statistically significant seasonal variations (all p > 0.05). A significant main effect of season was also found for the changes in IOP (p = 0.004) and objective refraction (p < 0.001). There was no season by refractive group interaction for any anterior segment angle parameter or IOP (all p > 0.05). CONCLUSION: There is a small but significant seasonal changes in the anterior segment angle parameters, refractive error, and IOP in healthy young adult males, in which the anterior segment angle dimensions are narrower, the IOP is higher, and the refraction is more myopic during winter.

Paracentral Acute Middle Maculopathy and Nonischemic Central Retinal Vein Obstruction in a Young Patient with Protein C Deficiency.

Purpose: To report a case of protein C deficiency with paracentral acute middle maculopathy (PAMM) and nonischemic central retinal vein obstruction (NI-CRVO). Case Report. A previously healthy twenty-one-year-old male was referred with sudden-onset, painless, unilateral paracentral scotomata in the right eye for a week. His uncorrected visual acuity was 20/20 in both eyes. In fundus examination of the right eye, mild venous tortuosity, retinal hemorrhages, and a gray-white opacity in the papillomacular bundle were observed. In the macular spectral-domain optical coherence tomography images, a hyperreflective band was noticed at the level of the inner nuclear layer, indicating PAMM. Fundus appearance and fluorescein angiography findings indicated NI-CRVO diagnosis made. The systemic and laboratory evaluations disclosed a protein C deficiency. Conclusion: In this report, in a healthy young male, combined PAMM and NI-CRVO showed to be the cause of blurred vision in the setting of protein C deficiency.