Limited depth corneal punch

Abstract

A single-use adjustable depth trephine corneal punch device that allows a goal trephination depth of a donor cornea to be set and cut prior to a surgical procedure for cutting selected portions of an actual patient cornea. The corneal punch includes a punch block having a central well for receiving a donor cornea, a punch top mounted atop the punch block and having a central cylindrical opening coaxially aligned with the well, and means for cutting a selected portion of the donor cornea in the central well, wherein the means for cutting includes a punch blade mounted atop the punch top and through the opening for combined limited rotation less than about 312 degrees and limited axial movement from a reference or “start” point and into juxtaposed relation against the cornea and a limited axial downward movement during rotation wherein to make a shallow cut in the cornea.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application is a continuation application of U.S. patent application Ser. No. 16 / 661,232, filed Oct. 23, 2019, which in turn claims the benefit of U.S. Provisional Patent Application Ser. No. 62 / 749,366, filed Oct. 23, 2018, for a Limited Depth Corneal Punch, the disclosures of which is hereby incorporated by reference in its entirety, including the drawings.BACKGROUND OF THE INVENTION1. Field of the Invention[0002]The present invention pertains to a single-use adjustable depth trephine device that allows a goal trephination depth of a donor cornea to be set and cut prior to a surgical procedure for cutting selected portions of an actual patient cornea.2. Description of the Prior Art[0003]Corneal transplant trephine devices were introduced in the 1980's for the cutting of donor cornea tissue in cases of cornea transplants. Typically, the diseased patient cornea was replaced with the donor tissue using a procedure called penetrating ke...

AI Technical Summary

Benefits of technology

The present invention is about a device that allows for the removal of a portion of cornea from a donor cornea for use in a surgery that needs to be performed on a patient. The device includes a punch block with a well for receiving the donor cornea, a punch top with a cylindrical opening, and a means for cutting a selected portion of the donor cornea. The means for cutting includes a punch blade mounted atop the punch top that combines limited rotation and axial movement to provide a shallow cut in the cornea. The device also includes a blade holder for positioning the cutting end of the blade atop the donor cornea. The blade holder has a groove for limiting its movement. The bottom of the reference cylinder is designed to match the curvature of the well in the punch block and engage the selected area of the cornea. The technical effect of this invention is to provide a precise and safe tool for removing corneal tissue from a donor cornea.

Problems solved by technology

Rather than replace the entire cornea, which often leads to severe astigmatism because of the suturing required in the penetrating keratoplasty procedure, doctors are now replacing only the lower part of the cornea that includes the endothelium.

However, using this “touch” method is inaccurate and requires a certain amount of skill in this medical art.

There is no known device that has a rotating blade in a punch top for use with harvesting donor tissue.

The narrow range of angles produced by the Moria trephine is important because it indirectly affects the depth penetration and applications and is, therefore, not practical for use in harvesting donor tissue because it would require manual positioning in a separate punch block.

Images