Optical coherence tomography angiography parameters in patients on hydroxychloroquine therapy

Area of Science:

• Ophthalmology
• Retinal Imaging
• Pharmacological Research

Background:

• Hydroxychloroquine (HCQ) is widely used for autoimmune diseases.
• Long-term HCQ use can lead to retinal toxicity.
• Early detection of retinal changes is crucial for patient management.

Purpose of the Study:

• To evaluate subclinical retinal microvascular changes in long-term HCQ users (≥5 years).
• To compare retinal parameters between HCQ users and a healthy control group using OCTA.
• To assess the potential of OCTA in identifying early HCQ-induced retinal alterations.

Main Methods:

• A case-control study involving 59 HCQ users and 59 controls.
• Optical coherence tomography angiography (OCTA) was used to assess foveal avascular zone (FAZ), macular vessel density (VD) in superficial and deep capillary plexus (SCP and DCP), and retinal thickness.
• Statistical analyses included independent t-tests, Mann-Whitney U tests, and Spearman's rank correlation.

Main Results:

• No significant differences in FAZ area or central foveal thickness (CFT) between groups.
• Significant parafoveal and perifoveal retinal thinning observed in HCQ users (p<0.001).
• Significantly higher macular VD in the foveal and parafoveal deep capillary plexus (DCP) of HCQ users (p<0.001).

Conclusions:

• Long-term HCQ use is associated with significant parafoveal and perifoveal retinal thinning.
• OCTA reveals variable microvascular changes in long-term HCQ users.
• OCTA shows promise for the early detection of HCQ-induced retinal alterations.