Phenotypic heterogeneity in family members of patients with retinitis pigmentosa

Purpose: To describe the phenotypic variations in family members of patients with retinitis pigmentosa (RP) with different modes of inheritance and to assess the ocular abnormalities in RP families. Methods: A descriptive analysis of three types of inheritance of RP was carried out, where 64 family members were examined at a tertiary eye care center, South India. They underwent comprehensive eye examination, fundus photography, fundus autofluorescence (FAF), full?field electroretinogram (FFERG), and spectral domain optical coherence tomography (SD?OCT). Analysis was performed between mild and severe forms of abnormalities to delineate retinal structural and functional defects in RP families. Results: The mean age was 38.55 ± 17.95 years. Males were 48.4%. In autosomal recessive and X?linked recessive groups, 74.2% and 77.3%, respectively, were asymptomatic, whereas in autosomal dominant group, 27.3% were asymptomatic. The proportion of the cases with abnormalities in all three groups was higher on ERG (59.6%), followed by OCT (57.5%), visual acuity (43.7%), peripheral FAF (23.5%), and macular FAF (11.8%). However, these abnormalities and the clinical pictures of the family members had no statistical difference across the three groups of inheritance. Conclusion: Structural and functional retinal alterations were noted in four out of five asymptomatic members, suggesting the need for careful screening of RP families and the pressing need for pre?test (genetic) counseling

Imaging drusens using spectral domain optical coherence tomography

Purpose: the purpose was to evaluate pathological changes of photoreceptor layer and retinal pigment epithelium in eyes with drusens using Spectral Domain Optical Coherence Tomography [SD-OCT]

Methods: twenty-nine eyes of 29 patients with [drusens] dry age-related macular degeneration and 43 eyes of 43 controls were included in this study. All subjects underwent complete ophthalmic examination including SD-OCT. Central foveal thickness [CFT], photoreceptor layer [PRL] thickness and retinal pigment epithelial [RPE] thickness were measured and compared between the groups. P value < 0.05 was considered statistically significant

Results: best corrected visual acuity [BCVA] ranged between 20/20 and 20/200. RPE [36.10 +/- 5.48 [micro]m Vs 39.27 +/- 4.30] and PRL thickness [53.93 +/- 7.36 [micro]m Vs 61.20 +/- 4.50 [micro]m] were significantly reduced in patients with drusens compared to controls. Increase in age was a significant risk factor for drusens [OR: 1.22, p < 0.001] and increased PRL thickness was a protective factor [OR: 0.720, p = 0.002]. PRL thickness was significantly associated with BCVA [p = 0.019]

Conclusion: with an increased resolution of SD-OCT, the involvement of the outer retinal layers was more clearly defined. SD-OCT may allow for the early detection of exudative changes

Macular thickness measurements using copernicus spectral domain optical coherence tomography

To provide normal macular thickness measurements using Spectral Domain Optical Coherence Tomography [SDOCT, Copernicus, Optopol Technologies, Zawierci, Poland]. Fifty-eight eyes of 58 healthy subjects were included in this prospective study. All subjects had comprehensive ophthalmic examination including best-corrected visual acuity [BCVA]. All the subjects underwent Copernicus SDOCT. Central foveal thickness [CFT] and photoreceptor layer [PRL] thickness were measured and expressed as mean and standard deviation. Mean retinal thickness for each of the 9 regions defined in the Early Treatment Diabetic Retinopathy Study was reported. The data were compared with published literature in Indians using Stratus and Spectralis OCTs to assess variation in instrument measurements. The mean CFT in the study sample was 173.8 +/- 18.16 microns [131-215 microns] and the mean PRL thickness was 65.48 +/- 4.23 microns [56-74 microns]. No significant difference [p = 0.148] was found between CFT measured automated [179.28 +/- 22 microns] and manually [173.83 +/- 18.1 microns]. CFT was significantly lower in women [167.62 +/- 16.36 microns] compared to men [180.03 +/- 18 microns] [p = 0.008]. Mean retinal thickness reported in this study was significantly different from published literature using Stratus OCT and Spectralis OCT. We report the normal mean retinal thickness in central 1 mm area to be between 138 and 242 microns in Indian population using Copernicus SDOCT. We suggest that different OCT instruments cannot be used interchangeably for the measurement of macular thickness as they vary in segmentation algorithms

Spectral domain optical coherence tomography characteristics in diabetic retinopathy

To report the appearance of diabetic retinopathy lesions using spectral domain optical coherence tomography [SD-OCT]. A total of 287 eyes of 199 subjects were included. All the subjects underwent complete ophthalmic examination including SD-OCT. The appearance of various lesions of diabetic retinopathy and the retinal layers involved were reported. In subjects with macular edema the prevalence of incomplete PVD was 55.6%. SD-OCT brings new insights into the morphological changes of the retina in diabetic retinopathy

Communications between intraretinal and subretinal space on optical coherence tomography of neurosensory retinal detachment in diabetic macular edema

The pathogenesis of development and progression of neurosensory retinal detachment [NSD] in diabetic macular edema [DME] is not yet fully understood. The purpose of this study is to describe the spectral domain optical coherence tomography [SD-OCT] morphological characteristics of NSD associated with DME in the form of outer retinal communications and to assess the correlation between the size of communications and various factors. This was an observational retrospective nonconsecutive case series in a tertiary care eye institute. We imaged NSD and outer retinal communications in 17 eyes of 16 patients having NSD associated with DME using SD-OCT. We measured manually the size of the outer openings of these communications and studied its correlation with various factors. Statistical analysis [correlation test] was performed using the Statistical Package for Social Sciences [SPSS] software [version 14.0]. The main outcome measures were correlation of the size of communications with dimensions of NSD, presence of subretinal hyper-reflective dots, and best-corrected visual acuity [BCVA]. The communications were seen as focal defects of the outer layers of elevated retina. With increasing size of communication, there was increase in height of NSD [r = 0.701, P = 0.002], horizontal diameter of NSD [r = 0.695, P = 0.002], and the number of hyper-reflective dots in the subretinal space [r = 0.729, P = 0.002]. The minimum angle of resolution [logMAR] BCVA increased with the increasing size of communications [r = 0.827, P< 0.0001]. Outer retinal communications between intra and subretinal space were noted in eyes having NSD associated with DME. The size of communications correlated positively with the size of NSD and subretinal detachment space hyper-reflective dots, and inversely with BCVA

Prevalence of myopia and its association with diabetic retinopathy in subjects with type II diabetes mellitus: a population-based study

To report the prevalence of myopia and its association with diabetic retinopathy in subjects with type II diabetes mellitus and compare the diabetic retinopathy status in the myopic group vs the emmetropic group. Population-based study. The population-based study estimated the prevalence of myopia from 1058 subjects, who were more than 40 years old and had type II diabetes mellitus; the patients were enrolled from a cross-sectional study. Participants answered a detailed questionnaire and underwent biochemical, physical and comprehensive ocular examination which included grading of nuclear sclerosis by lens opacities classification system III [LOCS III], seven field fundus photography and ultrasonography. Diabetic retinopathy and diabetic maculopathy were graded using the Klein's classification and early treatment diabetic retinopathy study [ETDRS] criteria respectively. The prevalence of mild, moderate and high myopia in type 2 diabetes was 15.9, 2.1 and 1.9% respectively. The prevalence of any myopia was found to be 19.9% in our study population. After adjusting the age, gender, duration of diabetes, hemoglobin A1c and other factors, increasing age was associated with mild and moderate myopia [OR 1.11 [95% CI 1.05 - 1.18]]. Compared to emmetropia, complete posterior vitreous detachment [CPVD] was associated with high myopia [50% Vs 12.2%, P < 0.0001]. Myopia had no association with diabetic retinopathy. The prevalence of myopia and high myopia was found to be 19.9 and 1.9% respectively among subjects with type II diabetes. Myopia was not associated with diabetic retinopathy, thereby, suggesting the need for a longitudinal study

Prevalence of visual impairment and associated risk factors in subjects with type II diabetes mellitus: Sankara Nethralaya diabetic retinopathy epidemiology and molecular genetics study [SN-DREAMS, report 16]

To report the prevalence of visual impairment [VI] and the associated risk factors in type II diabetic subjects. The study included type II diabetes mellitus subjects who were enrolled from a cross-sectional study. Participants underwent biochemical testing and comprehensive ocular examination including stereo fundus photography. The VI was defined based on the World Health Organization criteria. The prevalence of VI was 4% in the cohort. The risk factors associated with the presence of VI included a female gender, age greater than 60 years, low socio-economic status, hypertension, microalbuminuria, macroalbuminuria, neuropathy, use of insulin and alcohol. Various ocular risk factors are nuclear sclerosis, subjects who have undergone cataract surgery, myopia and sight-threatening diabetic retinopathy [STDR]. After adjusting for the factors using stepwise logistic regression analysis, hypertension, use of alcohol, post-cataract surgery and myopia were not risk factors. Stepwise logistic regression analysis indicated that VI was higher among subjects older than 60 years [odds ratio [OR]: 4.95 [2.67-9.15]] and those who belonged to a low socio-economic status [OR: 2.91 [1.24-6.85]]. The systemic risk factors for VI included microalbuminuria [OR: 2.91 [1.59-5.33]], macroalbuminuria [OR: 4.65 [1.57-13.77]] and presence of neuropathy [OR: 1.97 [1.09-3.59]] among subjects. Subjects with nuclear sclerosis [OR: 36.82 [11.12-112.36]] and presence of STDR [OR: 4.17 [1.54-11.29]] were at a higher risk of VI. Cataract was the most common cause of VI in the cohort. Visual impairment, among type II diabetic subjects [4%], is a major public health problem that needs to be addressed. Cataract is the most common reversible cause of vision impairment in this population

Morphological and Functional Correlates in Goldmann-Favre Syndrome: A Case Series

The purpose of this study is to describe the correlation of findings between results from spectral domain optical coherence tomography (SD-OCT) and microperimetry in a case series regarding patients with Goldmann-Favre syndrome. Goldmann-Favre syndrome is a rare autosomal recessive hereditary vitreo-retinal degeneration that impacts the functionality of vision in subjects. Three men with this condition were assessed and subjected to microperimetry and SD-OCT. Two of the men were brothers. This study finds that the retinoschisis and macular cystoid changes noted in the SD-OCT matched the scotomas revealed by the microperimetry. The findings of each of the individual cases are reported herein.

Intraocular Pressure and Its Determinants in Subjects With Type 2 Diabetes Mellitus in India / 예방의학회지

OBJECTIVES: This study was conducted to show the intraocular pressure (IOP) distribution and the factors affecting IOP in subjects with type 2 diabetes mellitus (DM) in India. METHODS: We measured the anthropometric and biochemical parameters for confirmed type 2 DM patients. A comprehensive ocular examination was performed for 1377 subjects aged > 40 years and residing in Chennai. RESULTS: A significant difference in IOP (mean +/- standard deviation) was found between men and women (14.6+/-2.9 and 15.0+/-2.8 mmHg, p = 0.005). A significantly elevated IOP was observed among smokers, subjects with systemic hypertension and women with clinically significant macular edema (CSME). After a univariate analysis, factors associated significantly with higher IOP were elevated systolic blood pressure, elevated resting pulse rate and thicker central corneal thickness (CCT). In women, elevated glycosylated hemoglobin was associated with a higher IOP. After adjusting for all variables, the elevated resting pulse rate and CCT were found to be associated with a higher IOP. CONCLUSIONS: Systemic hypertension, smoking, pulse rate and CCT were associated with elevated intraocular pressure in type 2 DM. Women with type 2 DM, especially those with CSME, were more prone to have an elevated IOP.

Effect of Illumination on Colour Vision Testing with Farnsworth-Munsell 100 Hue Test: Customized Colour Vision Booth versus Room Illumination

PURPOSE: To evaluate a customized, portable Farnsworth-Munsell 100 (FM 100) hue viewing booth for compliance with colour vision testing standards and to compare it with room illumination in subjects with normal colour vision (trichromats), subjects with acquired colour vision defects (secondary to diabetes mellitus), and subjects with congenital colour vision defects (dichromats). METHODS: Discrete wavelengths of the tube in the customized booth were measured using a spectrometer using the normal incident method and were compared with the spectral distribution of sunlight. Forty-eight subjects were recruited for the study and were divided into 3 groups: Group 1, Normal Trichromats (30 eyes); Group 2, Congenital Colour Vision Defects (16 eyes); and Group 3, Diabetes Mellitus (20 eyes). The FM 100 hue test performance was compared using two illumination conditions, booth illumination and room illumination. RESULTS: Total error scores of the classical method in Group 2 as mean+/-SD for room and booth illumination was 243.05+/-85.96 and 149.85+/-54.50 respectively (p=0.0001). Group 2 demonstrated lesser correlation (r=0.50, 0.55), lesser reliability (Cronbach's alpha, 0.625, 0.662) and greater variability (Bland & Altman value, 10.5) in total error scores for the classical method and the moment of inertia method between the two illumination conditions when compared to the other two groups. CONCLUSIONS: The customized booth demonstrated illumination meeting CIE standards. The total error scores were overestimated by the classical and moment of inertia methods in all groups for room illumination compared with booth illumination, however overestimation was more significant in the diabetes group.

Diabetic retinopathy in type II diabetics detected by targeted screening versus newly diagnosed in general practice

<p><b>INTRODUCTION</b>The aim of this study was to compare the occurrence of diabetic retinopathy in targeted screening diabetic patients (Group I) with newly diagnosed diabetic patients in general practice (Group II).</p><p><b>MATERIALS AND METHODS</b>This was an observational cross-sectional study. Data were obtained from 25,313 subjects who participated in the diabetic screening camps, and 128 newly diagnosed diabetes who presented to the diabetic retinopathy screening camps in general practice in rural and urban south India. The study variables were collected from all patients who underwent eye examination from the target screening detected diabetics [(n = 173) Group I] and those newly diagnosed in general practice [(n = 128) Group II]. The variations in prevalence of diabetic retinopathy and sight-threatening diabetic retinopathy in Group I and Group II and the factors affecting it were identified.</p><p><b>RESULTS</b>The occurrence of diabetic retinopathy was 6.35% (95% CI, 2.5-9.5) in Group I and 11.71% (95% CI, 5.6-16.4) in Group II. No significant difference was observed on occurrence of diabetic retinopathy, including sightthreatening retinopathy, in rural versus urban population and in Group I versus Group II. Patients diagnosed in general practice (Group II) with systolic blood pressure (BP) >140 were more likely to have retinopathy (P = 0.02).</p><p><b>CONCLUSIONS</b>Diabetic retinopathy including sightthreatening complications was found at the time of diagnosis of diabetes in the targeted screening group as well as in newly diagnosed diabetics in the general practice group.</p>