Application of SS-OCTA to evaluate the effects of long-term hydroxychloroquine treatment on retinal structure and microcirculation in patients with systemic lupus erythematosus.

Propose: The application of swept-source optical coherence tomography angiography (SS-OCTA) technique is used to detect the effects of long-term use of hydroxychloroquine (HCQ) on retinal structure and microcirculation in patients with systemic lupus erythematosus (SLE) before visual dysfunction occurs.

Methods: Retrospective case-control study. A total of 73 SLE patients (73 eyes) who had taken HCQ regularly for a long period of time were included as the SLE patient group, while 21 healthy individuals (21 eyes) were included as the control group. Based on the duration of HCQ use (HCQ course), the SLE patient group was divided into baseline group (6 months ≤ medication time < 1 year), low-risk group ( 1 year ≤ medication time < 5 years), and high-risk group (medication time ≥ 5 years). All participants underwent bilateral SS-OCTA macular imaging (6 mm*6 mm), slit-lamp examination, non-contact tonometry, computerized visual field (30 - 2) test, and fundus autofluorescence imaging (FAF).

Results: Compared among the groups, the full-layer retinal thickness and superficial blood vessel density of the fovea, below the inner circle, temporal side of the outer circle and above the outer circle decreased in the macular area (6 mm*6 mm) in high-risk group of SLE patients, while the area and circumference of FAZ increased (P < 0.0125). Correlation analysis suggested that the duration of SLE disease and HCQ cumulative dose were negatively correlated with superficial retinal capillary plexus vessel density (SCP-VD) in the three regions of inner retina, full-layer retinal thickness in the fovea, fovea, temporal side of the inner circle, and above the inner circle (r < 0,P < 0.05), and positively correlated with the area and circumference of FAZ (r > 0,P < 0.05).

Conclusion: Analysis by SS-OCTA examination showed that long-term HCQ treatment had adverse effects on the inner retina, SCP-VD and FAZ parameters in subclinical SLE patients without visual impairment.