The Barron Donor Cornea Punch® is a disposable, single-use instrument for the harvesting of donor corneal tissue for corneal keratoplasty procedures such as penetrating keratoplasty and the more recently developed endothelial keratoplasty. The punch set is comprised of a nylon cutting block and a top that contains the cutting blade. It is delivered with a plastic ring that protects the blade during shipment. The top, blade protector ring, and cutting block are held together with a silicone band, and the assembly is hermetically packaged in a pouch and sterilized with ethylene oxide.
The punch features a solid stainless steel blade that is permanently mounted in a nylon housing with four stainless steel guide posts to align with four corresponding holes in the cutting block. The guide posts, which are precision aligned with the blade, accurately center the blade over the donor cornea as the tissue is cut. The well of the cutting block has four small holes that may be inked with a sterile marking pen (included) to identify the four quadrants of the cornea for cardinal suture alignment in the recipient bed.
The punch has been redesigned to incorporate a nylon top that has openings to provide a view of the donor tissue as it is being cut. This enables the surgeon to verify the correct seating of the top, and the desired location of the cut before preforming the trephination.
The blades in the BPI punches were modified in 2020 to use a thinner wall that is 0.13 mm thick, which provides a razor-sharp cutting edge. Unlike punches from other suppliers that use a bent razor blade, the Barron Donor Punches® have a perfectly circular and uninterrupted cutting edge. In addition, the single bevel edge ensures the inside wall of the blade that is adjacent to the harvested tissue is perfectly vertical, thereby minimizing tension and distortion of the endothelial tissue during the trephination.
The blade of the Barron Donor Cornea Punch® is fabricated from the hardest stainless steel that is available, and its manufacture employs a proprietary, multiple stage honing of the blade edge to give an unsurpassed sharpness
The holes in the cutting block are located approximately 0.6 mm inside the edge of the cut that will be made by the blade. The marking can either be done from the top of block prior to placement of the donor tissue (see left diagram), or from the bottom after the donor tissue has been placed in the well of the cutting block and the top put in place.
The Barron Donor Cornea Marking Punches® come in 14 sizes, with blade diameters ranging from 6.0 mm to 9.5 mm. There are two families of vacuum trephines that can be used in conjunction with the donor punches: the Hessburg-Barron Vacuum Trephine® and the Barron Radial Vacuum Trephine?.The Barron Donor Cornea Punches are sold only through Distributors. They are sold as the on Marking Donor Punch® by JedMed Instruments and as the Barron Donor Cornea Punch® by Katena Products. Contact one of these distributors to purchase these punches.