The impact of removing the epiretinal membrane and inner limiting membrane for sustained subretinal fluid by macular neovascularization refractory to anti-VEGF therapy.

Purpose: Anti-vascular endothelial growth factor (VEGF) therapy is the most prevalent intervention for exudative lesions secondary to neovascular age-related macular degeneration (nAMD) and other macular neovascularization (MNV). However, in some cases refractory to the latest anti-VEGF agents is associated with epiretinal membrane (ERM) or vitreomacular traction. We applied a vitrectomy to remove those pathologies which may be effective for reducing the exudation. Observations: In this case report, we present 2 cases with sustained subretinal fluid and macular neovascularization secondary to nAMD or dome-shaped macula that poorly responded to anti-VEGF therapy. In both cases, removing thin ERM or vitreomacular traction with an inner limiting membrane peeling promptly resolved the subretinal fluid and no recurrence was observed thereafter. Conclusions and importance: Vitrectomy could be an effective modality for anti-VEGF drug-resistant MNV cases with vitreomacular traction or ERM even in the anti-VEGF era.

Histological investigation of rabbit ligamentum flavum with special reference to differences in spinal levels.

The structure of the ligamentum flavum has yet to be fully elucidated and no studies have investigated fine structural differences at different spinal levels in any animals. The aim of the present study was to clarify structural differences in the ligamentum flavum at different spinal levels (cervical: C3/4 and C5/6; upper thoracic: T2/3; lower thoracic: T9/10; lumbar: L3/4) using light and electron microscopy of rabbit specimens. Light microscopy using resorcin-fuchsin staining revealed that the distribution of elastic fibers was diffuse in the cervical and upper thoracic regions, but was generally dense in the lower thoracic and lumbar regions. Electron microscopy demonstrated that the cervical and upper thoracic regions were rich in collagen fibers. Conversely, the lower thoracic and lumbar regions were rich in elastic fibers. Quantitative image analyses displayed thick elastic fibers in the lower thoracic and lumbar regions, with high area ratios. Radiographic examinations revealed that ranges of motion were large at the cervical region, but small at the lower thoracic and lumbar regions. These findings suggest that structure of the ligamentum flavum varies at different spinal levels with respect to differences in motion.