Harmeet S. Gill, MD (North York, Canada), Melanie Kirby-Allen, MD, FRCP (Toronto, Canada), Wai-Ching Lam, MD, FRCS (Toronto, Canada)


Individuals with sickle cell disease (SCD) are at risk for developing proliferative retinopathy and visionthreatening complications. This study aims to determine the prevalence and age of onset of clinically significant retinopathy, and to suggest an appropriate timeframe for referral to ophthalmology.


We reviewed consecutive records from 1987 to 2005 retrospectively for children with SCD referred t o the Ophthalmology Service at the Hospital for Sick Children, Toronto. Data obtained included age, sex, sickle cell genotype, and presence of systemic manifestations of SCD. The genotypes hemoglobin SS, SC, and SB-Thalassemia were considered separately for univariate and survival analyses.


The hemoglobin SS group consisted of 163 patients. Over follow-up, 1 patient (0.06%) had PR (age at first eye findings 16 y), 23 patients (14.1%) had non-proliferative retinopathy (NPR), and 139 patients (85.3%) had no retinopathy. The hemoglobin SC group consisted of 73 patients. Over follow-up, 6 patients (8.2%) had PR (age at first eye findings: mean =13.7y, median =13y, range =9-18y), 18 patients (24.7%) had NPR, and 49 patients (67.1%) had no retinopathy. The hemoglobin SB-Thalassemia group consisted of 27 patients. Over follow-up, no patients had PR, 3 patients (11.1%) had NPR, and 24 patients (88.9%) had no retinopathy. In all genotypes, the survival rates for time to retinopathy based on age, sex, and presence of systemic manifestations were not statistically significant. The odds ratio estimate of developing retinopathy for the SC versus SS genotypes was 3.153 (95% confidence interval [CI] 1.593-6.241).


Proliferative retinopathy is a rare event in the pediatric sickle cell population. We recommend SC patients be referred for full ocular examination at age 9 years and be followed biennially if normal. For the hemoglobin SS and other genotypes, PR is more rare, and so patients can be referred for ocular examination at age 13 years and followed biennially if normal.