En face OCT detects and monitors HCQ toxicity in Asian patients

The extent and progression of hydroxychloroquine (HCQ) retinopathy can be monitored using en face OCT, according to this retrospective study.

Study design

The authors used swept-source OCT to perform imaging and segmentation of the outer photoreceptor layers on 62 eyes of 31 Asian patients with HCQ retinopathy. The images were qualitatively and quantitatively analyzed and correlated with fundus autofluorescence and visual field findings.

Outcomes

The images revealed a beaten-bronze appearance in areas with photoreceptor defects, while intact photoreceptors had smooth surfaces. Investigators could gauge retinopathy progression by monitoring areas of intact photoreceptors for change over several visits. Information derived from the OCT images was consistent with findings from 30-2 visual field examinations.

Limitations

We know from earlier work by Marmor and colleagues that HCQ retinopathy manifests differently in Asian patients compared with other ethnicities. All eyes in this study had confirmed HCQ toxicity with standard means. It is unclear if this modality can be used to screen patients with mild disease.

Clinical significance

Hydroxychloroquine retinopathy remains a potential cause of vision loss. Ophthalmologists often struggle trying to balance 2 competing goals: preventing patients from losing vision from HCQ toxicity versus enabling patients to continue a drug that is otherwise helpful to them and safe for the vast majority of patients. En face imaging—a quick and easy test—may represent another way to help diagnose eyes with HCQ toxicity and to follow them over time.