Abstract
Purpose: :
To determine correlation between retinal thickness measured by optical coherence tomography (OCT) and visual acuity (VA) in patients with central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO). Symptom duration and subclassifications of macular edema were also examined.
Methods: :
Charts of patients who had been evaluated for the diagnosis of CRVO or BRVO were retrospectively reviewed. Eyes that underwent both OCT and flourescein angiography (FA) were included. Reasons for exclusion included resolved retinal edema, presence of macular ischemia, blood in the fovea, dense cataract, prior history of amblyopia, or visually significant age–related macular degeneration. Macular edema was classified into 3 categories based on OCT: cystoid macular edema (CME) only, subretinal fluid (SRF) only, and CME with SRF. When available, symptom onset reported by the patient was recorded.
Results: :
Fifty eyes of 49 patients were included in the study. There were 18 eyes of 17 patients with CRVO and 32 eyes of 32 patients with BRVO. Twenty two patients were male and 27 were female. The average age was 68.2 (+/–13.2) for the CRVO group and 67.2 (+/– 13.4) for the BRVO group. Nineteen patients with CRVO and 15 patients with BRVO were excluded from the study based upon the above exclusion criteria. Average retinal thickness was 618 +/– 171 µm for the CRVO group and 402 +/– 146 µm for the BRVO group. Symptom duration was known for 33 of 50 eyes. Mean duration was 159 +/– 205 days for the CRVO group and 260 +/– 329 days for the BRVO group. Mean VA, expressed as log MAR, was 0.99 +/– 0.61 for the CRVO group and 0.71 +/– 0.49 for the BRVO group. There was a moderate correlation between retinal thickness and VA: all study eyes, r=0.51; CRVO group, r=0.36; BRVO group, r=0.54. There was a moderate correlation between retinal thickness and VA for the groups with CME only (r=0.50) and SRF only (r=0.51), but not for CME with SRF group (r=–0.048). Correlation between retinal thickness and VA existed for symptom duration < 6 months (r=0.54), but not for groups with duration between 6 months and < 18 months (r=–0.001) and duration > 18 months (r=–0.034).
Conclusions: :
Macular thickness measured by OCT shows a moderate correlation with VA in eyes with CRVO and BRVO. The strongest correlation was found in eyes with BRVO and with symptom duration < 6 months. When type of edema was subclassified, retinal thickness and VA correlated moderately for eyes that had either CME or SRF alone, but not for those that had CME and SRF.
Keywords: vascular occlusion/vascular occlusive disease • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • visual acuity