Does QuantiFERON-Positive Tubercular Serpiginous-Like Choroiditis Affect Retinal and Choroidal Structures Differently in Affected Eyes Compared to Fellow Eyes and Healthy Controls? A Comparative OCT and OCT-A Study

Purpose To evaluate long-term structural and microvascular alterations in QuantiFERON-positive tubercular serpiginous-like choroiditis (TB-SLC) using swept-source OCT and OCT angiography, and to compare affected eyes with fellow eyes and healthy controls.Methods This retrospective cohort study included 11 patients (16 affected eyes) with QuantiFERON-positive TB-SLC and 20 age- and sex-matched healthy controls (40 eyes). In unilateral cases, fellow eyes served as internal controls. Best-corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI), and vessel density (VD) of the superficial (SCP), deep (DCP), and choriocapillaris (CC) plexuses, along with foveal avascular zone (FAZ) parameters, were analyzed.Results Mean follow-up duration was 73.6 ± 44.8 months. BCVA improved significantly from 0.68 ± 0.34 to 0.42 ± 0.29 logMAR (p = .004). CMT decreased from 412.6 ± 98.3 µm to 321.4 ± 74.5 µm (p = .001), SFCT from 287.5 ± 72.1 µm to 251.8 ± 65.4 µm (p = .018), and CVI from 0.61 ± 0.05 to 0.58 ± 0.04 (p = .032). Despite clinical improvement, affected eyes showed significantly reduced VD compared with controls, with diffuse sectoral reductions in the CC and DCP (all p ≤ .004), while SCP changes were less pronounced. Deep FAZ area was significantly enlarged in affected eyes (p = .004), whereas superficial FAZ did not differ. In unilateral cases, fellow eyes were comparable to controls, while affected eyes had reduced CC and DCP VD, enlarged deep FAZ, and worse BCVA (all p < .01). Greater baseline inflammatory severity was associated with poorer outcomes.Conclusion In TB-SLC, clinical improvement does not necessarily indicate complete microvascular recovery. Persistent CC and DCP impairment and deep FAZ enlargement suggest long-term chorioretinal remodeling, highlighting OCTA metrics as potential biomarkers of residual vascular damage.