Abstract
Purpose:
We evaluated the progression of hydroxychloroquine (HCQ) retinopathy after stopping the drug, relative to the severity of initial damage.
Methods:
Eleven patients were studied with HCQ retinopathy graded as early (patchy parafoveal damage on fields and/or OCT); moderate (ring damage but no visible retinopathy); severe (damage extends to the RPE). Each was followed for 13-40 months after the drug was stopped. Measurements include visual acuity, 10-2 automated fields, SD-OCT and fundus autofluorescence. SD-OCT results were quantified by the Zeiss Cirrus ETDRS cube values, and by direct measurement of the ellipsoid zone (EZ) line.
Results:
Severe cases showed progressive and prominent thinning of the fovea and parafovea, expansion of visible retinopathy, and shortening of the EZ line, throughout the follow-up period. Visual acuity and visual fields did not change significantly except for acuity in one severe case in which the foveolar EZ line was lost. Moderate cases also showed progressive thinning, but it was most prominent in the first year and there was no progression of EZ line damage. Visual acuity and fields showed no consistent changes. Early cases were stable for all parameters with a hint of some possible EZ line repair.
Conclusions:
Severe HCQ retinopathy can progress steadily post-treatment for at least 40 months, and vision is threatened as foveolar cone structure becomes disrupted. Moderate cases progress less and retain foveolar architecture. Early cases do not progress. We cannot rule out the possibility of later progression in early and moderate cases, but the likelihood of foveal damage seems minimal. The status of foveal outer segment markers is probably a critical parameter for judging the risk to visual acuity. Our data suggest that early recognition of HCQ retinopathy is highly relevant to reduce late progression and to prevent visual loss.
Keywords: 688 retina •
585 macula/fovea •
503 drug toxicity/drug effects