Identification and management of different types of bacillary layer detachment in eyes with rhegmatogenous retinal detachment

PURPOSE: To describe the preoperative and postoperative features of eyes with fovea-off rhegmatogenous retinal detachment (RRD) and different types of bacillary layer detachment (BALAD), which consists of an intraretinal split within the photoreceptor inner segment myoid zone or formation of a inner lamellar defect at the fovea visible on spectral-domain optical coherence tomography (OCT). METHODS: Retrospective cohort study of patients with primary RRD and BALAD who underwent pars plana vitrectomy (PPV). OCT, multicolor images, and logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuities (BCVAs) were obtained preoperatively and at 1, 3, 6, and 12 months after the operation. Three types of BALAD were identified preoperatively on the basis of OCT: cavity, transition and lamellar hole. RESULTS: Among the 42 eyes included, 23 were classified as cavity, 6 as transition and 13 as lamellar hole BALAD. All types showed a sharp red round area at the fovea on multicolor images. After standard PPV, additional internal limiting membrane (ILM) peeling was carried out in none eyes with cavity BALAD, in 2 eyes with transition BALAD and in all BALAD-lamellar hole eyes. Post-operatively, no eyes showed evidence of full-thickness macular hole (FTMH). At 12 months post-operatively, external limiting membrane (ELM) and ellipsoid zone (EZ) appeared continuous in 69% (29/42) eyes (24 cavity/transition and 5 BALAD lamellar-hole, P = 0.006) and 54.8% (23/42) eyes (20 cavity/transition and 3 BALAD lamellar-hole, P = 0.004), respectively. Accordingly, BCVA was worse in the eyes with BALAD-lamellar hole than in those with cavity/transition BALAD (0.6 ± 0.4 vs. 0.3 ± 0.2; P = 0.01). CONCLUSION: Multicolor imaging is useful to identify BALAD. Cavity and transition BALAD are likely to not progress to FTMH after retinal reattachment. ILM peeling and cover flap prevented FTMH formation in eyes with BALAD-lamellar hole in this cohort. 12 months postoperatively, restoration rates of integrity of ELM and EZ bands and BCVA scores remained lower in eyes with BALAD-lamellar hole in comparison to those with cavity/transition BALAD.