The keratotomy is a complex manoeuvre involving a number of steps performed in quick succession.  Careful wound construction creates a self-sealing incision to minimise leakage of fluid during the operation and reduce the risk of postoperative leakage. Keratome blades vary not just in size and geometry, but cut differently depending on the brand of the manufacturer.  Positioning of the keratotomy is critical as too limbal results in bleeding with chemosis and too corneal causes astigmatism.  Upon entry into the eye, collateral damage to the endothelium, iris, anterior capsule and lens needs to be avoided.