Air travel with intraocular gas. II. Clinical considerations.

The patient with a residual intraocular gas volume of 0.6 mL, approximately 10% of the volume of the eye, can compensate for the decrease in cabin pressure as an airplane ascends without a symptomatic rise in intraocular pressure. Larger volumes may be accommodated in aircraft that decompress to less than 8000 ft or that take off from altitudes above sea level. The patient with residual intraocular gas who experiences pain or dimness of vision in an ascending airplane can obtain relief if the cabin altitude is decreased by 2000 ft. This will require a modest adjustment in the altitude of the airplane.