High intraocular pressure in four vitrectomized eyes with intravitreal C3F8 without high altitude travel

It is well known that altitude ascent with intravitreal gas can cause expansion of gas and intraocular pressure (IOP) elevation. According to Boyle's law, the gas bubble will not expand unless a higher altitude than the gas insertion site has been reached. We report four cases in which intravitreal gas was injected at an altitude of 790 m (Jerusalem). All four cases developed high IOP even though they did not reach a higher altitude in their post-operative period.A report of four patients following vitrectomy with 12% mixture of perfluoropropane and air are presented. All four patients arrived with ocular pain following the ascent by car of 765-1100 m to Jerusalem where the vitrectomy and gas insertion was conducted. Upon examination, all four patients had high IOP (30-55 mm Hg). IOP was well controlled with IOP-lowering medications. None of the patients suffered from long-term complications.Caution should be taken with altitude changes in patients with intravitreal gas even if there was no ascent from the altitude in which the vitrectomy was performed.