Fundus auto fluorescence and spectral domain ocular coherence tomography in the early detection of chloroquine retinopathy

Purpose: To determine the sensitivity of spectral domain ocular coherence tomography (SD-OCT) and fundus auto fluorescence (FAF) images as a screening test to detect early changes in the retina prior to the onset of chloroquine retinopathy. Method: The study was conducted using patients taking chloroquine (CQ), referred by the Rheumatology Department to the Ophthalmology Department at Tygerberg Academic Hospital. Group A consisted of 59 patients on CQ for less than 5 years, and Group B consisted of 53 patients on CQ for more than 5 years. A 200 × 200 macula thickness map, 5-line raster SD-OCT on a Carl Zeiss Meditec Cirrus HD-OCT and FAF images on a Carl Zeiss Meditec Visucam 500 were recorded for 223 eyes. Images were reviewed independently, and then those of Groups A and B compared. Results: There were no statistically significant differences between Groups A and B. The criteria included the internal limiting membrane and the retinal pigment epithelium (ILM-RPE) thickness, interdigitation zone integrity ( p = 0.891, df = 1, χ ² = 0.1876), ellipsoid zone integrity ( p = 0.095, df = 2, χ ² = 4.699) and FAF image irregularities ( p = 0.479, df = 1, χ ²= 4995978). Conclusion: The inclusion of SD-OCT and FAF as objective tests into the prescribed screening guidelines does not appear to simplify the detection of subclinical injury in patients on chloroquine treatment.