Abstract
Purpose:
Diabetic retinopathy is among the leading causes of preventable vision loss in working-aged individuals, and early diagnosis may prevent progression to advanced disease. Our objective is to study the potential use of a retinal acuity meter (RAM) with a brightness acuity meter (BAM) as a screening tool to identify patients with early diabetic macular edema.
Methods:
Three groups of patients were identified in the ophthalmology clinic at Bellevue Hospital Center in New York: diabetics with known macular edema, diabetics without edema, non-diabetic patients. Recovery time was measured after a 15-second macular photostress using the RAM and BAM. Macular edema was diagnosed by ophthalmoscopy and confirmed by measuring macular thickness via Heidelberg Spectralis optical coherence tomography (OCT). A Mann-Whitney test was used for statistical analysis.
Results:
38 eyes from 21 patients were analyzed. Retinal acuity ranged from 20/20 to 20/200 and macular photostress recovery time ranged from 10 to 46 seconds. When comparing eyes with macular edema to controls, macular photostress recovery was slightly delayed in patients with edema (mean recovery time 23.2s v. 21.0s), but did not reach statistical significance. There was a mildly positive correlation between recovery time and central foveal thickness by OCT (Pearson’s correlation coefficient, p=0.13). The relationship between central foveal thickness or photostress recovery and hemoglobin A1c (HbA1c) were also analyzed, but did not show significant correlation.
Conclusions:
Patients with diabetic macular edema demonstrated slightly delayed macular photostress recovery time although the data did not reach statistical significance. A larger sample size may confirm this finding. Given the ease of use, the RAM and BAM may be used by non-ophthalmologists internists as a screening test of macular function in patients with diabetes. Early referrals to ophthalmologists based on these screening results may result in prevention of irreversible vision loss.
Keywords: 499 diabetic retinopathy •
498 diabetes •
505 edema