Choroidal Hyperreflective Foci in Stargardt Disease Shown by Spectral-Domain Optical Coherence Tomography Imaging: Correlation With Disease Severity

IMPORTANCE: The presence of choroidal hyperreflective foci in Stargardt disease is, to our knowledge, a potentially new finding. Evaluation of these foci may aid in better understanding of the disease process. OBJECTIVES: To report the presence of choroidal hyperreflective foci in spectral-domain optical coherence tomography (SD-OCT) images from eyes with Stargardt disease and investigate the relationship between the number of hyperreflective foci and disease severity. DESIGN, SETTING, AND PARTICIPANTS: Twenty-six eyes of 13 patients with a clinical diagnosis of Stargardt disease were evaluated in a retrospective case series. Patient data were collected between January 1, 2009, and August 31, 2014. MAIN OUTCOMES AND MEASURES: The number of choroidal hyperreflective foci in Stargardt disease as well as correlation with visual acuity, central macular thickness (CMT), and disease duration were the main outcomes. A total of 707 macular SD-OCT scans of 13 patients with Stargardt disease were reviewed and evaluated for the presence and number of retinal/choroidal hyperreflective foci, central macular thickness, visual acuity, and disease duration. Enhanced depth imaging with OCT (EDI-OCT) scans available for 2 patients were compared with SD-OCT scans. A PubMed/Google search was performed to identify SD-OCT images in Stargardt disease; these findings were reviewed for the presence of choroidal hyperreflective foci. RESULTS: The mean (SD) numbers of hyperreflective foci in each retinal/choroidal layer in decreasing frequency were as follows: Bruch membrane/retinal pigment epithelial (RPE) complex, 78.22 (24.39); choriocapillaris, 25.77 (17.57); Sattler layer, 18.59 (12.89); outer retina, 16.64 (6.96); inner retina, 0.95 (1.58); and Haller layer, 0.73 (0.87). The number of hyperreflective foci in the Bruch membrane/RPE complex increased exponentially with decreasing CMT (R2 = 0.99; P = .008). The number of hyperreflective foci in the Bruch membrane/RPE complex, choriocapillaris, and Sattler layer increased proportionally with decreasing visual acuity (R2 = 0.97, R2 = 0.95, and R2 = 0.99, respectively; and P = .007, P = .006, and P = .008, respectively). Direct correlation existed between the number of hyperreflective foci in the choriocapillaris and the Sattler layer and disease duration (R2 = 0.98 and R2 = 0.99, respectively; and P = .006 and P =.009, respectively). In the 10 studies on Stargardt disease, choroidal hyperreflective foci were present in 51 of 54 SD-