The Barron Vacuum Donor Cornea Punches are second-generation marking punches that incorporate a vacuum to hold the donor cornea firmly in place during the resection of the transplant tissue from donor corneas. These donor punches build on BPI’s experience with the design and manufacture of vacuum trephines and non-vacuum donor cornea punches. The instrument is delivered in a sterile, hermitically-sealed tray with Tyvek lid. It is disposable and is intended for single use.
The Barron Vacuum Donor Cornea Punch is comprised of 5 components:
- Cutting Block (Base)
- Top with Blade
- Seating Ring
- Vacuum Syringe
- Gentian Violet Ink Pen
The cutting block (or base) of the the punch features a circular groove and 4 holes for aspirating the epithelial side of the cornea. These small holes are also used to mark the cornea as described below. There are 4 larger precisely-located corner holes that accept aligning pins that are in the punch top. A small-diameter, flexible silicone tube is attached to side of the base so that a vacuum can be created with the hand-operated vacuum syringe.
The punch top contains a stainless steel blade that is matched in diameter to the small vacuum holes in the base. Four stainless steel guide posts align with four corresponding holes in the cutting block, which accurately centers the blade over the donor cornea.
The seating ring is used to ensure complete contact between the peripheral cornea and the vacuum groove so that a perfectly round button can be cut from the center of the cornea.
The well of the cutting block has four small holes that may be inked with a sterile gentian violet marking pen (included) prior to placement of the donor cornea in order to identify the four quadrants of the cornea for cardinal suture alignment in the recipient bed. When the vacuum is applied to the cutting block, the epithelium of the donor cornea is pulled firmly against the 4 holes and the gentian violet ink is transferred to the cornea.
The blade of the 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 blades in the BPI punches are 0.3 mm thick, which yields sturdy blades that are less subject to accidental damage that might be caused by the surgeon or assistant during preparation for the operation.
Demonstration of the Barron Vacuum Donor Cornea Punch being used by a cornea surgeon
The Barron Vacuum Donor Cornea Punches come in 13 sizes, ranging from 6.0 mm in diameter 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.