Abstract
Purpose :
To examine the relationship of cataract surgery to the thickness of individual retinal layers as estimated by optical coherence tomography (OCT) analysis using the Iowa Reference Algorithms in a large population based study of older adults.
Methods :
Participants (n=1913) in the 2008-2010 BDES examination phase underwent OCT imaging. The macula images were segmented into 10 retinal layers: nerve fiber (NFL), ganglion cell (GCL), inner plexiform (IPL), inner nuclear (INL), outer plexiform (OPL), outer nuclear (ONL), inner segment/outer segment (IS/OS), outer segment junction (OSJ), outer photo receptor (OPR) and the retinal pigment epithelial (RPE). The mean thickness of each layer was calculated averaging the 4 subfields in the inner ring of the Early Treatment Diabetic Retinopathy Study grid. OCT scans were excluded for participants with diabetes, late macular degeneration, full thickness macular holes, and scans with poor quality. Lens status was determined by history and confirmed by slit lamp and red reflex photographs. Participants with or without cataract, as determined by standardized grading, had similar results so were combined in this analysis.
Results :
The mean age of participants was 75 (range 63-100) years. Total retinal thickness within the inner ring was marginally thicker in eyes with cataract surgery (N=461, mean 329.8 µm) compared to eyes without (N=1613, mean 326.6 µm) after adjustment for age and sex (p=0.07). This was attenuated with additional adjustment for presence of epiretinal membrane, vitreomacular traction and partial thickness holes (p=0.305). Specific layers show different patterns. The NFL (p<.001), INL (p=0.04), IS/OS (p=0.002) and OSJ layers (p=0.05) are thicker in persons with cataract surgery compared to those without. The GCL (p=0.09) and OPR (p=0.07) layers are slightly thinner for eyes with surgery. Eyes where the surgery had been at least 5 years prior did not show as much thickening as those with surgery within the past 5 years, but both groups still had thicker retinal layers than persons without surgery. Similar associations were found in the central circle and outer ring.
Conclusions :
Overall, eyes that have undergone cataract surgery appear to have thicker retinal layers on OCT analysis than eyes without surgery. These data suggest that lens status should be taken into account when examining relationships of retinal thickness as determined by OCT.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.