Three Simple Approaches to Visualize the Transparent Vitreous Cortex during Vitreoretinal Surgery

Background: Initial historical considerations to perform a pars plana vitrectomy were made for opaque vitreous cortex due to dense asteroid hyalosis or vitreous hemorrhages. However, current indications for vitreoretinal surgery include mainly vitrectomies in the presence of a clear vitreous, for example retinal detachments, epiretinal membranes or macular holes, thus visualization of the transparent vitreous gel facilitates proper vitreous removal. Materials and Methods: The transparent structure of the vitreous cortex as well as the thin epiretinal membrane may become visible during surgery by mild vitreous hemorrhages or intravitreous application of 0.05 ml crystalline triamcinolone acetonide. Eyes with a significant breakdown of the blood-retinal barrier accumulate intravenously applied vital dyes, for example fluorescein, in the vitreous cavity. Results: Mild accidental intraoperative bleedings or intended injection of 0.05 ml autologous blood may help to stain transparent vitreous structures and visualize the remaining vitreous. Intravitreous triamcinolone crystals attach to the surface of the vitreous cortex, bursa premacularis or retina itself allowing better visualization of a controlled vitreous removal. A preoperative diagnostic fluorescein angiography in eyes with active uveitis or diabetic retinopathy may lead to a moderate accumulation of the dye in the vitreous cavity and greenish staining of the vitreous cortex at the vitreoretinal interface. Discussion: A safe and complete removal of clear vitreous or transparent membranes may be achieved by the intraoperative application of autologous blood or triamcinolone. The preoperative systemic application of fluorescein greatly enhances the visualization of previously clear structures.