Choroidal thickness on optical coherence tomography as a longitudinal predictor of visual outcomes in intermediate uveitis.

To assess longitudinal changes in subfoveal choroidal thickness (SFCT) and mean choroidal thickness (MCT) in intermediate uveitis, eyes with at least one follow-up visit were included. These eyes were stratified into clinically worsened, stable, or improved based on changes in clinical parameters including Standardization of Uveitis Nomenclature (SUN) classification, to evaluate their prognostic value for future best-corrected visual acuity (BCVA) and central retinal thickness (CRT). Spectral domain optical coherence tomography (Heidelberg Engineering, Germany) was used to image the central macula. SFCT, MCT, and CRT were measured manually within the central 1 mm. Mixed-effects regression analysis controlling for age and sex was used to evaluate the prognostic value of SFCT and MCT regarding future BCVA and CRT. A total of 91 eyes from 52 patients were included in the analysis. While 12 eyes worsened, 62 remained stable, and 17 improved. Choroidal thickness remained stable over time, with no significant differences in SFCT or MCT change between clinical groups (p > 0.5 for all). When controlling for age and sex, both the baseline SFCT (estimate = -0.35 × 10- ³ logMAR per µm, p = 0.040) and MCT (estimate = -0.42 × 10-³ logMAR per µm, p = 0.018) were prognostic for future BCVA. MCT, but not SFCT, was significantly associated with future CRT (estimate = -0.15 μm per µm, p = 0.010 vs. -0.13 μm per µm, p = 0.140). Choroidal thickness in terms of baseline SFCT and MCT is prognostic of future BCVA and could serve as a prognostic structural biomarker for intermediate uveitis.