Optical Coherence Tomography Protocols for Screening of Hydroxychloroquine Retinopathy in Asian Patients

Abstract

To investigate the distribution of outer retinal changes in hydroxychloroquine (HCQ) retinopathy and explore optical coherence tomography (OCT) protocols to maximize the sensitivity of HCQ retinopathy detection in Asian patients. Diagnostic validity assessment. Setting: Institutional. Forty-eight eyes (24 patients) with HCQ retinopathy underwent 6-mm horizontal and vertical line scans and 6× 6-mm2 volume scans using spectral-domain OCT (SD-OCT), and 9-mm line scans and 6× 6-mm2 and 12× 9-mm2 volume scans using swept-source OCT (SS-OCT). Distances from the fovea to the defective photoreceptors were measured in the temporal, nasal, superior, and inferior directions from line scan OCT images. The sensitivity of retinopathy detection, indicated by photoreceptor defects, was compared among protocols. Detection of photoreceptor defects and distances from the fovea to the defects. The average minimum distance from the fovea to an area of photoreceptor defects was 1.84±1.26mm (mean ± standard deviation). The distances were greater than 3mm horizontally and vertically in 15 (31.3%) and 17 (35.4%) eyes with HCQ retinopathy, respectively, and only wide-field line or volume scans could detect defects in the eyes. The 9-mm line scans detected HCQ retinopathy significantly better than 6-mm scans (P < .001); the sensitivity of the wide volume scan was significantly greater than the standard volume scan (P= .001). The 12× 9-mm2 volume scan detected retinopathy with the greatest sensitivity (100%). Our study recommends a wide-field OCT scan to screen Asian patients taking HCQ medications.