Abstract
Purpose :
Sickle cell patients are postulated to sustain sickling episodes in the retina that can result in ischemia and retinal infarction, which may manifest as retinal thinning. The purpose of this study is to investigate the prevalence of retinal thinning seen on spectral domain optical coherence tomography (SDOCT) imaging of sickle cell eyes.
Methods :
Sickle cell and control (age and race matched) subjects were prospectively enrolled from a university retina clinic into this observational study. Subjects underwent visual acuity testing, slit lamp biomicroscopy, dilated ophthalmoscopy and SDOCT imaging at baseline. Sickle cell retinal lesions, degree of vascular tortuosity, caliber of arteriovenous anastamoses and stage of retinopathy were noted. Early Treatment of Diabetic Retinopathy (ETDRS) subfield measurements were compared between sickle cell and control subjects and also amongst sickle cell hemoglobin subtypes. Associations between ETDRS subfield measurements and hemoglobin subtype, retinopathy stage and systemic diseases were assessed.
Results :
513 sickle cell eyes (260 patients) and 75 control eyes (39 patients) had median visual acuities of 20/20. There were 318 Hgb SS eyes (161 patients), 133 Hgb SC eyes (68 patients) and 62 Hgb SThal eyes (31 patients). Mean age was 38 years for sickle cell patients and 42 years for controls (P =0.045). The sickle cell retinopathy stages ranged from 0 to 5, with Stage 2 as the predominant type for Hgb subtypes SS (267 of 318, 84 %) and SThal (48 of 62,77.4 %) eyes but Stages 2 and 3 were about equal in Hgb SC eyes ( Hgb (Stage 2: 64 of 133, 48.1%; Stage 3: 55 of 133, 41.4%). ETDRS central (P=.002), inner (nasal P=.009, superior P=.021, temporal P<.001, inferior P=.017) and temporal outer (P=.012) subfield measurements were thinner in sickle cell compared with control eyes. Hemoglobin SS eyes had significantly thinner inner ETDRS subfield measurements compared with SC and SThal eyes. Retinal thinning in all subfields was associated with age (P=.017). Various subfields were associated with stage of retinopathy, vascular tortuosity, presence of hemorrhage, seafans and sunburst lesions. No association was found between retinal thinning and usage of hydroxyurea usage or arteriovenous anastamosis caliber.
Conclusions :
The macula is thinner in sickle cell compared with control eyes; retinal thinning correlates with age, sickle cell stage and is most severe in hemoglobin SS subtypes.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.