The role of the vitreous in the intraocular pressure rise after neodymium-YAG laser capsulotomy

H. D. Schubert, W. J. Morris, S. L. Trokel and E. A. Balazs

Autologous liquid vitreous injected into the anterior chamber of the phakic owl monkey eye leads to markedly increased intraocular pressure (IOP) peaking at one to two hours. In contrast, neodymium-YAG laser shock waves focused in the center of the anterior chamber of the same animal led to a mild decrease in IOP. Debris produced by laser pulses focused on the residual cortex of owl monkey eyes that had undergone extracapsular surgery failed to increase the IOP. Similarly, injection of dialyzed vitreous did not have any significant influence on IOP. We conclude that the disruption of the integrity of the anterior cortical gel and the subsequent release of a dialyzable intravitreal substance with a molecular weight of less than 10,000 daltons into the anterior chamber may contribute to the IOP rise after surgical discission, including neodymium-YAG laser posterior capsulotomy.