The microperimetry of resolved cotton-wool spots in eyes of patients with hypertension and diabetes mellitus.

BACKGROUND: Retinal cotton-wool spots (CWSs) are an important manifestation of retinovascular disease in hypertension (HTN) and diabetes mellitus (DM). Conventional automated perimetry data have suggested relative scotomas in resolved CWSs; however, this has not been well delineated using microperimetry. This study evaluates the retinal sensitivity in documented resolved CWSs using microperimetry. METHODS: Retinal CWSs that resolved after 10 to 119 months (median, 51 months) and normal control areas were photographed to document baseline lesions. Eye-tracking, image-stabilized microperimetry with simultaneous scanning laser ophthalmoscopy was performed over resolved CWSs, adjacent uninvolved areas near the lesion, and in location-matched normal patients (age-matched). RESULTS: A total of 16 eyes in patients with DM or HTN (34 resolved CWSs) and 16 normal control eyes (34 areas) were imaged. The mean (SD) sensitivity of resolved CWSs in the eyes of patients with HTN and DM was 11.67 (3.88) dB and 7.21 (5.48) dB, respectively. For adjacent control areas in the eyes of patients with HTN and DM, the mean (SD) sensitivity was 14.00 (2.89) dB and 11.80 (3.45) dB, respectively. Retinal sensitivity was significantly lower in areas of resolved CWSs than in the surrounding controls for patients with HTN (P = .01) and those with DM (P < .001). Scotomas in patients with DM were denser than those of patients with HTN (P < .05). CONCLUSIONS: Cotton-wool spots in patients with DM and HTN leave permanent relative scotomas detected by microperimetry. Scotomas are denser in eyes of patients with DM than in those with HTN. In addition, among patients with DM, adjacent retinas not involved with CWSs have lower retinal sensitivity than in age-matched controls.

The association between percent disruption of the photoreceptor inner segment-outer segment junction and visual acuity in diabetic macular edema.

PURPOSE: To evaluate the integrity of the photoreceptor inner segment/outer segment (IS/OS) junction using spectral-domain optical coherence tomography (SD OCT) in patients with diabetic macular edema and to correlate the relationship between the integrity of the IS/OS junction and visual acuity. DESIGN: Retrospective, comparative, consecutive case series. METHODS: Sixty-two eyes from 38 patients with diabetic macular edema underwent SD OCT imaging. For each patient, 2 experienced observers masked to visual acuity measured several SD OCT variables, including central macular thickness, retinal volume, global disruption scale of outer retina, percentage disruption of the outer retina, and history of previous treatments. Visual acuity recorded as number of Early Treatment Diabetic Retinopathy Study letters was used as the outcome variable in univariate and multivariate analysis testing the measured SD OCT variables as predictors. RESULTS: A statistically significant correlation between percentage disruption of the IS/OS junction and visual acuity was found (P = .0312). Additionally, there was a strong trend suggesting a relationship between macular volume and visual acuity, although borderline significance was found (P = .07). CONCLUSIONS: Disruption of the photoreceptor IS/OS junction is an important predictor of visual acuity among diabetic macular edema patients.

Mutation screening of patients with Leber Congenital Amaurosis or the enhanced S-Cone Syndrome reveals a lack of sequence variations in the NRL gene.

PURPOSE: To determine if mutations in the retinal transcription factor gene NRL are associated with retinopathies other than autosomal dominant retinitis pigmentosa (adRP). METHODS: Genomic DNA was isolated from blood samples obtained from 50 patients with Leber Congenital Amaurosis (LCA), 17 patients with the Enhanced S-Cone Syndrome (ESCS), and a patient with an atypical retinal degeneration that causes photoreceptor rosettes with blue cone opsin. The 5' upstream region (putative promoter), untranslated exon 1, coding exons 2 and 3, and exon-intron boundaries of the NRL gene were analyzed by direct sequencing of the PCR-amplified products. RESULTS: Complete sequencing of the NRL gene in DNA samples from this cohort of patients revealed only one nucleotide change. The C->G transversion at nucleotide 711 of NRL exon 3 was detected in one LCA patient; however, this change did not alter the amino acid (L237L). CONCLUSIONS: No potential disease causing mutation was identified in the NRL gene in patients with LCA, ESCS, or the atypical retinal degeneration. Together with previous studies, our results demonstrate that mutations in the NRL gene are not a major cause of retinopathy. To date, only missense changes have been reported in adRP patients, and sequence variations are rare. It is possible that the loss of NRL function in humans is associated with a more complex clinical phenotype due to its expression in pineal gland in addition to rod photoreceptors.