A flexible infusion micro-cannula for subretinal surgery.

Injection of fluids or drugs into the subretinal space is often necessary during subretinal surgery. The authors have developed a flexible micro-cannula for subretinal surgery that can be used for submacular injection of drugs or for atraumatic hydrodissection of the retina. The novel features of the soft tip include reduced diameter (200 microns), increased length, and material selection for resistance to tip buckling. The authors have used this cannula following pars plana vitrectomy for 14 patients with subfoveal choroidal neovascularization secondary to age-related macular degeneration (13 patients) and angioid streaks (1 patient). The cannula creates a relatively atraumatic retinotomy and allows an efficient, controlled injection of subretinal fluid. This micro-cannula seems to be a valuable tool for the subretinal infusion of fluids or drugs.