CORNEAL SEGMENT FOR TREATING KERATECTASIAS OF VARIOUS ORIGINS Russian patent published in 2014 - IPC A61F9/07 

FIELD: medicine.

SUBSTANCE: invention can be used for treating keratectasias of various origins by polymer keratoplasty with corneal segment (CS) implantation. That is ensured by making an integral CS of an optically transparent biocompatible material. The segment is ring-shaped with end openings. The CS length makes 90 to 220 angular degrees with an outer diameter of 7.1 mm and an inner diameter of 6.0 mm, with oval points. A CS cross-section is convex-convex for form outer and inner ribs in a junction of the two convex surfaces. A line connecting the ribs matches with a long axis of the CS cross-section. An anterior surface of the segment has a constant radius curve. An apex of the above curve is found on a cross axis of the segment. An inclination of the long section in relation to the CS plane makes 25-30 degrees. An apex of an anterior surface of the segment drawn from the apex of the curve to the middle of the long axis makes 150 to 350 mcm at a pitch of 50 mcm. An opposite convex portion of the CS facing a posterior surface of the cornea has a constant radius curve or reduces to an inner rib of the segment. An apex of the posterior surface of the segment is 50 mcm and drawn from the apex of the curve to the middle to the long axis or at 35 mcm from the inner rib respectively.

EFFECT: reducing high order aberration, stabilised progression of the disease, enlarged intact central optical area, enhancement and wider indications for photorefraction keratectomy as a method for residual ametropy correction.

3 dwg