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X-linked juvenile retinoschisis (XLRS) is an inherited retinal disease caused by mutations in the RS1 gene, resulting in splitting of the retinal layers and visual disturbances. To provide insights on this disease in our cohort, genetic examination, clinical presentation, and functional analysis were performed. We observed three main RS1 mutations in our cohort of six unrelated patients: RS1-D126G, RS1-R209H, and RS1-R213W. The RS1-D126G mutation, exclusively reported in Thai patients so far, showed the highest prevalence. Phenotypically, the D126G mutation manifested early (0.3–4 years old), presenting as asymmetrical visual acuity and schisis. Functional analysis revealed that the molecular pathomechanism of D126G was the failure of protein secretion attributable to endoplasmic reticulum retention. The understanding of the genotype-phenotype relationship and the pathomechanisms of specific mutations in a particular population could immensely benefit the pipeline of personalised treatment design for XLRS. [ABSTRACT FROM AUTHOR]

Alzheimer's disease is a type of neurodegenerative disorder that is characterized by the progressive degeneration of brain cells, leading to cognitive decline and memory loss. It is the most common cause of dementia and affects millions of people worldwide. While there is currently no cure for Alzheimer's disease, early detection and treatment can help to slow the progression of symptoms and improve quality of life. This research presents a diagnostic tool for classifying mild cognitive impairment and Alzheimer's diseases using feature-based machine learning applied to optical coherence tomographic angiography images (OCT-A). Several features are extracted from the OCT-A image, including vessel density in five sectors, the area of the foveal avascular zone, retinal thickness, and novel features based on the histogram of the range-filtered OCT-A image. To ensure effectiveness for a diverse population, a large local database for our study was collected. The promising results of our study, with the best accuracy of 92.17,% will provide an efficient diagnostic tool for early detection of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Purpose: To compare the efficacy in pupil dilatation between a mixture containing 0.75% tropicamide and 2.5% phenylephrine and the alternate application of 1% tropicamide and 10% phenylephrine eye drops. Material and Methods : Patients requiring pupil dilatation were randomized to receive one drop of the mixture every 10 min for four times or our standard application of one drop of 1% tropicamide alternating with one drop of 10% phenylephrine every 10 min for two cycles. Pupil size was measured under bright light with the pupil gauge before, and every 5 min after initial application for 40 min. Application of the drops was discontinued once the pupil diameter reached 7 mm. Blood pressure and pulse rate were monitored every 15 min. Results: Of 40 patients (age 57.3±10.9 years, range 35-70 years), 22 were randomized into the mixture group and 18 into the alternate drug group. Baseline pupil sizes were 1.7±0.5 mm in the mixture group and 1.8±0.4 mm in the alternate drug group. The pupils were successfully dilated to 7 mm within 40 min in 17 patients of the mixture group compared to seven patients in the alternate drug group ( P =0.004, Log Rank test). The mean pupil sizes at 40 min were 6.6±0.8 and 6.0±0.9 mm in the mixture and alternate drug groups respectively ( P =0.050, t-test). Blood pressure and pulse rate were stable and similar in both groups. Conclusions: The mixture of 0.75% tropicamide and 2.5% phenylephrine is superior to our standard application of 1% tropicamide alternating with 10% phenylephrine. It provides faster and more successful pupil dilatation within 40 min.

X-linked retinitis pigmentosa (XLRP), a rare form of retinitis pigmentosa (RP), is predominantly caused by mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene. Affected males often present with severe phenotypes and early disease onset. In contrast, female carriers are usually asymptomatic or show stationary phenotypes. Herein, we reported an 8-year-old female carrier, a daughter of a confirmed RP father with RPGR mutation, with an early onset of progressive cone-rod pattern retinal dystrophy. Additionally, the carrier experienced visual snow-like symptom as long as she recalled. Ophthalmological examination showed the reduction of visual acuity and attenuation of photoreceptor functions since the age of 5 years. Further analysis revealed a heterozygous pathogenic variant of the RPGR gene and a random X-inactivation pattern. Although she harboured an identical RPGR variant as the father, there were phenotypic intrafamilial variations. The information on the variety of genotypic and phenotypic presentations in XLRP carriers is essential for further diagnosis, management, and monitoring of these cases, including the design of future gene therapy trials. [ABSTRACT FROM AUTHOR]

Purpose: To describe the ophthalmic findings and mutation analyses of the PAX6 gene in Thai aniridia patients. Methods: Ten patients from six unrelated families underwent a comprehensive ophthalmic examination. Mutations in the PAX6 gene were screened by single-strand conformational polymorphism (SSCP) and direct DNA sequencing of the SSCP variants. Results: Seven patients developed cataracts and six developed glaucoma. Mutation analysis demonstrated four different truncating mutations, two of which were de novo. These included one novel insertion/deletion mutation (c.474del12insGA in exon 5) and three nonsense mutations. R203X and R240X are common recurrent mutations, while Q277X in exon 10 is novel. All mutations resulted in loss of function of the PAX6 protein. Conclusion: Our data confirm inter- and intrafamilial variable phenotypic manifestations of which the underlying mechanisms may be haploinsufficiency or dominant-negative mutation. [ABSTRACT FROM AUTHOR]

Objective: To examine subfoveal choroidal thickness (SFCT) in Thai population using enhanced depth imaging spectral- domain optical coherence tomography (EDI-OCT) and to study its correlation with foveal retinal pigment epithelium thickness (FRPE), central neurosensory retinal thickness (CNRT), age, and refraction., Material and Method: Four hundred eighty eyes from 240 subjects without glaucoma, retinal, or choroidal diseases underwent scanning of the retina and choroid using EDI-OCT SFCT FRPE, and CNRT measurements were based on the 1:1 micron images and wereperformed by two independent observers. The reliability ofmeasurements between the observers was evaluated by intraclass correlation coefficient (ICC). The correlations of SFCT with FRPE, CNRT, age, and refractive error were analyzed, Results: The mean age of the subjects was 36.22 years (range 20-81years). The means (95% reference intervals) of SFCT, CNRT andFRPE were 294.02 μm (137.14-450.90 μm), 174.22 μm (141.82-206.62 μm), and 41.94 μm (34.65-49.23 μm), respectively. SFCT and CNRThad excellent reliability between the two observers [ICC = 0.947 (95% CI, 0.918-0.963) and 0.929 (95% CI, 0.906-0.945), respectively], while FRPE showed good reliability [ICC = 0. 729 (95% CI, 0.637-0.793)]. SFCT had a low positive correlation with FRPE (r = 0.179, p<0. 0001) but not with CNRT (p = 0.317). SFCT showed a positive correlation with refraction (r = 0.338, p<0.0001) and a negative correlation with age (r = -0.166, p<0.0001). Regression analysis suggested that the SFCT decreased by 12.23 pm per one decade oflife and by 11.42 pm per one diopter of myopia., Conclusion: Normal values of SFCT in Thai population were obtained SFCT significantly decreased with older age and higher myopia. SFCT was associated with FRPE, reflecting the same vascular supply of the choroid and retinal pigment epithelium. When measured with our technique based on the 1:1 micron images, the reliability ofSFCT measurement was very high despite highly morphologic inter-individual variations.

Objective: To study the prevalence of optic atrophy in patients with proliferative diabetic retinopathy (PDR) who underwent intravitreal bevacizumab injection and risk factors associated with optic atrophy., Material and Method: A retrospective case control study enrolled 269 cases (394 eyes) of patients with PDR, in which 166 cases (219 eyes) received intravitreal bevacizumab injection. Associated factors such as type of DM, hemoglobin A1c level, hypertension, hypercholesterolemia, chronic kidney disease, previous intravitreal surgery retinal detachment, and vitreous hemorrhage were recorded. Criteria for diagnosis of optic atrophy were decreased visual acuity, pale optic disc and decreased nerve fiber layer thickness, which was measured by Stratus optical coherence tomography (OCT). The association between intravitreal bevacizumab injection and optic atrophy was analyzed by multiple logistic regression., Results: Two hundred sixty nine patients with PDR, consisting of 166 patients with intravitreal bevacizumab injection and 103 cases without bevacizumab injection. Optic atrophy was found in 11.4% (25/219 eyes) and 8% (14/175 eyes) respectively. There was no evidence that intravitreal bevacizumab injection and associated systemic diseases were related to optic atrophy. The risk factor that was related to optic atrophy was previous intravitreal surgery (adjusted odds ratio (OR), 2.57 [95% CI, 1.13, 5.84], p = 0.024)., Conclusion: Anti-VEGF (bevacizumab) does not increase the risk of optic atrophy. The ophthalmologists should be aware of subsequent optic atrophy development in patients with PDR who undergo surgical intervention.

Objective: To identify the prognostic factors that predict visual outcome in eyes with penetrating ocular injuries with retained intraocular foreign bodies (IOFBs)., Design: Retrospective cases series, Material and Method: The authors reviewed the records of 228 patients who had penetrating eye injuries with retained posterior segment IOFBs managed at Siriraj Hospital between June 1995 and February 2008. One hundred and forty-one patients (61.8%) were included in the present study. Associations between final visual outcome and various pre-operative and post operative variables were statistically analyzed., Results: After a mean follow-up of 10.4 +/- 7.7 months, 68 eyes (48.2%) achieved visual acuity of 6/18 or better The final visual acuity ranged between 6/24 and 6/60 in 22 eyes (15.6%) and 51 eyes (36.2%) had visual acuity less than 6/60. Final visual acuity significantly depended on initial visual acuity (p = 0.002), size of entry wound (p = 0.020), size of foreign body (p = 0.018), presence of vitreous hemorrhage (p = 0.014), retinal detachment (p = 0.026) and endophthalmitis (p < 0.0001)., Conclusion: Visual outcome in penetrating ocular injuries with retained IOFBs was affected by initial visual acuity, size of entry wound, size of foreign body, vitreous hemorrhage, retinal detachment and endophthalmitis. These factors may be helpful for pre-operative counseling and predicting the final visual outcome.

Background: Posterior capsule rupture is one of the most common intra-operative complications of cataract surgery and may lead to other sequelae that affect visual outcome., Objective: To determine the visual outcome and sequelae at 1 year after cataract surgery complicated by posterior capsule rupture and factors related to poor visual outcome., Material and Method: Retrospective chart reviews of the patients who underwent cataract surgery complicated by posterior capsule rupture in Siriraj Hospital between January 2006 and December 2009 were performed. Data collected included demographic data, underlying systemic diseases, pre-existing ophthalmic diseases, type of cataract, type of operation, vitrectomy methods, type of intraocular lens (IOL) implantation, pre-operative and post-operative visual acuity, subsequent complications and management., Results: There were 525 cases that received cataract surgery complicated by posterior capsule rupture. After excluding 280 cases with the follow-up period of shorter than 1 year 245 eyes of 242 patients were studied. These comprised 111 males and 131 females. The mean age was 69.3 years, ranged from 40 to 92 years. The mean logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA) at 1 year was 0.43 (median 0.24). The proportion of patients who had BCVA of 0.3 logMAR or better was 64.5%. After excluding eyes with pre-existing diseases, 72.9% got this level of BCVA. Vitrectomy was required in 75.5%; which consisted of anterior vitrectomy (68.6%) and posterior vitrectomy (6.9%). Primary intra-ocular lens insertion was performed in 87.4%, mostly in the ciliary sulcus (75.5%). Subsequent complications occurred in 13.9%, which included secondary glaucoma (4.9%), cystoid macular edema (2.4o), endophthalmitis (1.6%), rhegmatogenous retinal detachment (1.2%o), IOL displacement (1.2%), uveitis (1.2%), corneal decompensation (0.8%) and fibrous ingrowth (0.4%). The factors associated with the poor visual outcome worse than 0.3 logMAR were pre-existing ocular diseases, incision requiring more than 2 stitches, posterior vitrectomy and subsequent complications (p < 0.05)., Conclusion: Most of the patients had favorable visual outcome after cataract surgery complicated by posterior capsule rupture. Meticulous vitrectomy to prevent subsequent complications and foldable IOL insertion to minimize the wound size are recommended.

Objective: To evaluate the efficacy of nonmydriatic digital retinal images for determining diabetic retinopathy., Material and Method: Single field 45-degree digital retinal images of 225 eyes from 142 diabetic patients were obtained with a nonmydriatic camera. The images were diagnosed and graded by a general ophthalmologist. These results were compared with clinical diagnosis obtained by retinal specialists, after examination by using biomicroscope with plus lens and indirect ophthalmoscope of the patients. International clinical diabetic retinopathy disease severity scale was used for grading diabetic retinopathy in all cases., Results: Presence of diabetic retinopathy was detected in 70 eyes (31.1%). The sensitivity and specificity for determining diabetic retinopathy was 68.57% (95%CI 57.00-78.20) and 92.25% (95%CI 87.00-95.50), respectively. The positive predictive value and negative predictive value was 80.00% (95%CI 68.20-88.20) and 86.67% (95%CI 80.60-91.00). Overall accuracy was 84.89%., Conclusion: Single field 45-degree nonmydriatic digital retinal images were limited by fair sensitivity for determining diabetic retinopathy although overall accuracy from the present study was relatively high. Upcountry, this tool might facilitate increased access of diabetic patients for eye evaluation but cannot replace standard eye examination.

Objectives: To compare the incidence and characteristics of patients with endophthalmitis after extracapsular cataract extraction (ECCE) to those after phacoemulsification, Material and Method: Records of patients receiving intravitreal antibiotic injection to treat endophthalmitis after cataract surgery between Jan 2001 and Dec 2004 were reviewed. Demographic data and other characteristics including associated diseases, details of cataract surgical procedure and intraoperative complication, onset of endophthalmitis after cataract surgery, presenting symptoms and signs of endophthalmitis, how endophthalmitis was managed, causative organisms, duration of hospitalization and results of treatment were collected. This information was compared between those of endophthalmitis patients after ECCE and those after phacoemulsification., Results: There were 5 cases who developed endophthalmitis after ECCE and 31 cases after phacoemulsification. The incidence was 0.365% after ECCE and 0.279% after phacoemulsification (p = 0.589). Visual acuity (VA) before cataract surgery in ECCE group was worse than the phacoemulsification group (median VA: counting fingers vs 6/36, p = 0.001). Median onset of endophthalmitis was 8 days after ECCE and 6 days after phacoemulsification. Presenting symptoms and signs were similar. Causative agents were identified in 4 (80%) and 14 (45%) cases in the ECCE and phacoemulsification groups respectively. Gram-positive bacteria were the major cause of infection in both groups. Endophthalmitis caused by citrobacter sp. in ECCE group and enterococcus or streptococcus sps. the phacoemulsification in the group ended up with enucleation or no light perception., Conclusion: The present study has not demonstrated an apparent difference between endophthalmitis after ECCE and those after phacoemulsification. Endophthalmitis after either procedure can be managed as the same condition.

Aims: To compare the efficacy and ocular adverse effects of topical prednisolone acetate, ketorolac tromethamine, and fluorometholone acetate in reducing inflammation after phacoemulsification., Method: One hundred and twenty eyes were enrolled in a prospective, investigator-masked, randomized controlled trial. Each drug was prescribed 4 times a day for 28 days. The following data were recorded weekly: visual acuity, intraocular pressure, slit lamp biomicroscopy, grading of cells and flare in the anterior chamber, and ocular symptoms., Results: The number of eyes with a minimal amount of cells in the anterior chamber in the ketorolac group was less than the prednisolone group on day 7 (11:20, p = 0.008) and day 14 (23:31, p = 0.015), and than fluorometholone group on day 7 (11:21, p = 0.011). Intraocular pressure in the prednisolone group was higher than the ketorolac group on day 21 (14.6:12.2 mmHg, p = 0.016). One eye in the prednisolone group had intraocular pressure of 32 mmHg. Burning sensation was reported frequently in the ketorolac group., Conclusion: All 3 drugs were effective in reducing post-operative inflammation. The efficacy of prednisolone acetate and fluorometholone acetate was comparable. Ketorolac tromethamine showed less efficacy than corticosteroids, however, it did not induce ocular hypertension.