Drusen and RPE atrophy automated quantification by optical coherence tomography in an elderly population

Abstract

PurposeCorrelate OCT-derived measures of drusen and retinal pigment epithelium (RPE) atrophy areas (RAs) with demographic features in an elderly population.Patients and methodsSubjects aged 50 years and older underwent Cirrus OCT scanning. Drusen area and volume were obtained from the macula within a central circle (CC) of 3 mm and a surrounding perifoveal ring (PR) of 3-5 mm, using the RPE analysis software (6.0). RA measurements were generated for the 6 × 6 mm 2 retinal area. Gender, age, smoking status, and systolic blood pressure (SBP) were considered.ResultsA total of 434 eyes were included. RA was larger in women (0.63±0.16 vs 0.26±0.08 mm 2, P=0.05) and with increasing age. The PR drusen area increased with increasing age (P<0.001), whereas the CC drusen area remained stable after the age of 70 years (0.25±0.06 mm 2 for ages 70-79 years and 0.25±0.07 mm 2 for ages >80 years). Drusen volume in the CC was smaller after the age of 80 years (0.009±0.003 mm 3) compared with the 70- to 79-year-old group (0.02±0.008 mm 3). Drusen measurements were similar between smokers and nonsmokers, but the PR drusen area (0.29 mm 2, P=0.05) and volume (0.40 mm 3, P=0.005) were correlated with years smoked. RA (0.24 mm 2, P=0.10), PR drusen area (0.29 mm 2, P=0.05), and volume (0.40 mm 3, P=0.005) were found to be directly associated with SBP. There was a high correlation between the eyes of the same subject.ConclusionOCT-based automated algorithms can be used to analyze and describe drusen and geographic atrophy burden in such population-based studies of elderly patients.