Effect of Cataract Surgery onIntra-ocular Pressure

Abstract

Cataract is the opacity of the lens that leads to gradual painless blurring of vision and eventual loss of sight so it is the leading cause of self-declared vision impairment. It is one of the few normal physiological changes in the aging process, so its incidence increases with age and occurs on both eyes. Cataract surgery has become one of the most common elective surgical procedures as its volume has increased dramatically over the past 20 years, about 8 million cataract operation per year worldwide. Cataract extraction and intraocular lens implantation increases the width, depth, volume and angle of the anterior chamber in eyes with angle closure glaucoma, which in turn lead to decrease in the intraocular pressure(IOP) soon in the post-operative period. Although the facility of outflow is known to increase after cataract surgery, the angle width does not change in normal or open angle glaucoma patients after cataract surgery. This suggests improved function of trabecular meshwork itself rather than improved aqueous access to the trabecular meshwork. Also in primary open angle glaucoma, phacoemulsification alone may decrease intraocular pressure in patients with mild to moderate medically controlled glaucoma but in patients with uncontrolled progressive glaucoma, phaco trabeculectomy is needed.