Role of optical coherence tomography in assessment of anterior and posterior ocular changes in rheumatoid arthritis patients with and without dry eye

Aim To assess dry eye indices, choroidal thickness, retinal and optic disc vessel density in rheumatoid arthritis (RA) patients using anterior segment optical coherence tomography (AS-OCT), enhanced depth imaging OCT, and optical coherence tomography angiography, comparing them to healthy controls. Settings and design A prospective comparative observational study was conducted at the Ophthalmology Department of Ain Shams University Hospital between November 2022 and November 2024. Patients and methods Fifty eyes of 50 RA patients and 50 eyes of 50 healthy age-matched and sex-matched controls were included in this study. All participants underwent a comprehensive ophthalmic examination, including Schirmer test (I and II) and tear break-up time. AS-OCT was used to measure epithelial thickness, central corneal thickness, tear meniscus height, and tear meniscus area. Enhanced depth imaging OCT was used to measure subfoveal choroidal thickness. OCT angiography was used to assess superficial capillary plexus vessel density (VD), deep capillary plexus (DCP) VD, foveal avascular zone size, and radial peripapillary capillary VD. Results RA patients showed significantly lower Schirmer I (13.00±2.36 vs. 15.60±1.54 mm, P <0.001), Schirmer II (10.12±2.62 vs. 12.46±1.16 mm, P <0.001), tear break-up time (11.32±1.94 vs. 14.98±1.90 s, P <0.001), and tear meniscus area (0.02±0.01 vs. 0.03±0.01 mm 2 , P <0.001) compared to controls. Superior epithelial thickness was significantly thinner in RA patients (47.28±4.98 vs. 49.20±3.61 µm, P =0.030). Superficial capillary plexus VD was significantly lower in RA patients in superior (51.22±5.35 vs. 54.22±3.34%, P =0.001), nasal (50.00±4.99 vs. 52.50±4.01%, P =0.007), temporal (49.72±5.28 vs. 52.92±4.20%, P =0.001), and foveal (16.11±5.18 vs. 20.62±9.37%, P =0.004) regions. DCP VD was significantly lower in RA patients in inferior (54.30±5.52 vs. 56.80±3.95%, P =0.011) and superior (55.24±5.44 vs. 58.02±3.56%, P =0.003) regions. Disease duration showed a significant negative correlation with DCP VD in all quadrants except the fovea. Conclusion RA patients exhibit significant changes, including tear film instability, superior corneal epithelial thinning, and reduced retinal microvascular density in multiple retinal quadrants. The correlation between disease duration and DCP VD suggests progressive microvascular decrease with longer disease duration.