Abstract
Purpose :
A critical knowledge gap exists in how systemic disease markers relate to the clinical manifestations of sickle cell retinopathy (SCR). This prospective observational study investigated the link between hematologic values and retinal injury on OCT and cerebrovascular disease (CVD).
Methods :
73 patients (38 males), aged 5-20 years with sickle cell disease (SCD) (68 SS and 5 Sβ0 thalassemia) underwent funduscopy and SD-OCT imaging. 52 of these patients had brain MRI, 49 of the 52 also had MRA. Data on CVD include history of stroke, silent cerebral infarct (SCI) by MRI, cerebral arteriopathy by MRA and abnormal transcranial Doppler (TCD). Hematologic values and markers of hemolysis were collected. Χ2 and Fisher’s exact tests of proportions were used to compare frequency of abnormal findings across subpopulations. For continuous variables, 2-tailed, unpaired t tests were used for age and Mann-Whitney test were used for blood tests results. P values of <.05 were considered statistically significant.
Results :
While funduscopic findings in our cohort showed no correlation with CVD, 20/21 patients with CVD had evidence of SCR by OCT (p=0.008). The outcome of OCT detecting retinal injury from SCD had 95.24% sensitivity (95% CI 76.18% to 99.88%) and 38.71% specificity (95% CI 21.85% to 57.81%) of showing SCI by MRI. There was no significant correlation between OCT findings and abnormal TCD. Correlations of hematologic values with OCT and CVD are demonstrated in the table.
A logistic regression model was statistically significant (p = 0.000). The model explained 58.0% of the variance in SCI and correctly classified 84.6% of cases as with or without SCI. For each unit increase of reticulocyte, there was 1.43 times increase in the odds of SCI. Subjects with abnormal OCT were 11.5 times more likely to exhibit SCI on MRI. Increasing WBC, higher indirect bilirubin and AST were associated with an increased likelihood of having SCI.
Conclusions :
A correlation between abnormal OCT and CVD strongly suggesting that retinal OCT may aid in detection and monitoring SCD related CVD. A significant correlation between higher reticulocyte percentage, higher AST and abnormal OCT, stroke and SCI suggests that retinopathy may be another component of the hemolytic sub-phenotype of SCD and that patients with higher levels of hemolysis may benefit from closer monitoring for the development of SCR and brain damage.
This is a 2021 ARVO Annual Meeting abstract.