BACILLARY LAYER DETACHMENT IN PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT

PURPOSE: To evaluate the frequency, clinical and optical coherence tomography (OCT) predictors, and postoperative anatomical and functional outcomes of bacillary layer detachment (BALAD) in eyes undergoing surgical repair for fovea-off rhegmatogenous retinal detachment (RRD). METHODS: This retrospective, single-center observational study was conducted at a tertiary eye care hospital in India. Primary fovea-off RRD that underwent surgical repair between January 2020 and December 2024 were analyzed. Preoperative spectral-domain OCT images were reviewed for BALAD and other predefined retinal biomarkers. Clinical and imaging parameters were compared between the BALAD and non-BALAD groups. Univariate and multivariable logistic regression analyses identified predictors of BALAD formation. Occurrence rate and preoperative predictors of BALAD were analyzed, and postoperative macular reattachment, external limiting membrane/ellipsoid zone continuity, best-corrected visual acuity, and single-surgery success were assessed over 24 weeks. RESULTS: Two hundred and seventy primary fovea-off RRD eyes were analyzed. BALAD was detected in 51 eyes (18.9%). Younger age ( P = 0.014) and greater subretinal fluid height ( P = 0.002) were independent predictors of BALAD. Anatomical reattachment rates at 24 weeks were 88.5% in BALAD eyes and 77.3% in non-BALAD eyes ( P = 0.286). External limiting membrane/ellipsoid zone restoration occurred in 42.3% and 33.3%, respectively ( P = 0.247). Best-corrected visual acuity improvement trajectories were similar, though slower in BALAD eyes ( P < 0.001). Resurgery rates were comparable between groups ( P > 0.999). CONCLUSION: BALAD is a relatively common OCT feature in fovea-off RRD, predominantly affecting younger, fluid-rich eyes with higher subretinal fluid height. Its presence does not adversely affect anatomical reattachment or single-surgery success.