Inflow and outflow relations after intraocular fluid-Healon exchange in a case of chronic ocular hypotension.

A 47-year-old patient was legally blind in her only eye for months due to long-lasting ocular hypotension following chronic uveitis and several operations for cataract and secondary glaucoma. With injections of 0.7 to 2.5 cc 1% Healon into the anterior chamber and vitreous cavity at intervals of 2 to 12 months, intraocular pressure levels between 5 and 12 mmHg could be maintained resulting in an improvement of the visual acuity up to 25/100. The treatment has been continued for over 5 years. A positive correlation was found between the volume of injected Healon and the integral of intraocular pressure over time, and between visual acuity and pressure level. Reduced aqueous flow, high trabecular outflow resistance, and a low rate of clearance of Healon from the vitreous cavity is obviously responsible for the long-lasting elevation of low intraocular pressure levels and for the restoration of useful vision.