Research SummaryEvaluation of cornea friendly phaco-tip position during clear corneal phacoemulsification cataract surgery: a randomised, triple-blind, parallel group trial of phacoemulsification with bevel-up versus bevel-down
Corneal endothelial damage following phacoemulsification still remains to be a major concern of modern day cataract surgery. Corneal decompensation is the most common (0.5%) surgical complication resulting in poor vision. With the increasing number of surgeries to curb cataract blindness, it is logical to expect the number of decompensated corneas to increase. With the current trends, it can be estimated that about 31,500 cases of bullous keratopathy may be added every year to the existing load of corneal blindness which is potentially preventable.
In theory, damage to the corneal endothelium is minimised by delivering the lowest phaco energy only in the direction necessary to emulsify the lens nucleus. Furthermore, phacoemulsification should occur in the posterior chamber rather than in the iris plane or the anterior chamber. The convention is to turn the bevel towards the nucleus. Few hypothesise that in the bevel-up technique, the phaco tip, and therefore the source of heat, are farther from the endothelial cells, thereby decreasing the chance of endothelial cell damage. There is no conclusive evidence to affirm the most cornea friendly phaco tip position. This prospective randomised, parallel group, exploratory, triple-blind trial intends to establish evidence in this regard.
Figure Legend: Figure 1: Burden of corneal blindness in India Figure 2: Estimated requirement of corneal transplants in India per year Figure 3: Phaoemulsification with bevel-up and bevel-down technique