Gel injection adjustable keratoplasty

Abstract

The present invention provides a surgical technique that allows for subtle modification of the corneal curvature by interlamellar injection of a synthetic gel at the corneal periphery while sparing the optical zone. The gel viscosity, volume and disposition within the surgical annular track as well as the diameter of the track, width, depth, and location are all parameters in the refractive change obtained. Following ultrasonic pachymetry performed centrally and at a selected wound entrance located about 2.5 to 3.5 mm from the apex, a one millimeter or so wide, about 75-85% corneal thickness depth radial incision is performed with a micrometric diamond knife adjusted to about 86% corneal thickness. Inserted through the partial-depth incision, a corkscrew-like dissector or helicoidal spatula forms a 360.degree. annular track centered about the apex. Shaped like the dissector, a modified 30 gauge needle is fully inserted in the intralamellar track and a transparent gel is manually injected while retracting the needle, thus filling the annular channel. Using a surgical keratometer mounted to an operation microscope, the final corneal power is adjusted by massaging and removing the gel as necessary.

Dependencies are inferred from the claim text.