Chemical vitrectomy: change of solid gel vitreous to sol for vitrectomy by changing pH of vitreous toward the slight acid side.

Solid gel vitreous was changed to sol by changing the pH of the vitreous toward the slightly acid side by using diluted acetic acid of various weak concentrations. For human and rabbit vitreous in vitro, the gel sol change with regard to time in respect to concentration of the weak acid was noted. Rabbit eyes in vivo were used. In vitro and in vivo complete change of gelly vitreous to sol was achieved in about one hour by use of 0.3 mL of 0.5% acetic acid without any effect on the retina, choroid, optic disc, or the lens. This chemical vitreous fragmentation for vitrectomy was tried successfully on human eyes using 0.5 mL of 0.5% acetic acid without any bad effect in cases of vitreous hemorrhage not clearing in two months, posterior perforating injuries, and before cutting vitreous bands. A simplified method for pars plana irrigation drainage of liquid or chemically liquefied vitreous is described.