Evaluation of photoreceptor outer segment length in hydroxychloroquine users.

Objective: This study aims to evaluate the photoreceptor outer segment (PROS) length in patients who use hydroxychloroquine (HCQ) prior to the development of retinopathy.

Methods: In this prospective, single-centre, comparative study, 44 patients using HCQ for ≥5 years, 30 patients using HCQ <5 years, and 45 age- and sex-matched healthy controls were enrolled. The participants underwent a detailed ophthalmologic examination, spectral-domain optical coherence tomography (SD-OCT) imaging, and 10-2 automated visual field testing.