PERFLUOROPROPANE 12-PERCENT VERSUS 20-PERCENT - EFFECT ON INTRAOCULAR-PRESSURE AND GAS TAMPONADE AFTER PARS-PLANA VITRECTOMY

A randomized prospective study was performed on 30 nonglaucomatous eye s undergoing pars plana vitrectomy and intraoperative fluid-gas exchan ge, comparing the effect of two perfluoropropane gas concentrations (1 2% and 20%) on postoperative intraocular pressure, early postoperative bubble size, and intravitreal longevity. No significant differences i n mean intraocular bubble size at 36 to 48 hours and mean peak and fin al follow-up intraocular pressure were found between the 12% group (n = 15) and the 20% group (n = 15, unpaired T-test). Intravitreal longev ity was significantly greater for the 20% concentration (mean +/- stan dard deviation = 8.4 +/- 1.8 weeks) compared with the 12% concentratio n (mean +/- standard deviation = 6.7 +/- 1.6 weeks). In nonglaucomatou s eyes under careful observation and appropriate antiglaucoma therapy, the choice between a 12% or 20% concentration of perfluoropropane gas determined primarily longevity of gas tamponade rather than postopera tive pressure or early bubble size.