The Barron Radial Vacuum Trephine is a second-generation corneal trephine that is similar in operation to the Hessburg-Barron Vacuum Trephine. Like the Hessburg-Barron Vacuum Trephine, the Radial Vacuum Trephine utilizes a vacuum to hold the cornea against thetrephine during the trephination of the cornea, and needs no auxiliary vacuum equipment. It uses a simple hand-operated syringe to create the vacuum. The use of a stabilizing vacuum causes the cornea to be held in its natural contour, thereby producing a perpendicular incision in the cornea to provide an optimal recipient opening for donor tissue. The instrument is fabricated from the highest grade stainless steel and FDA-approved polymer materials. It is delivered in a transparent plastic tray with a hermetically sealed Tyvek lid.
The Barron Radial Vacuum Trephine was developed to assist physicians in the placement of corneal sutures. This is accomplished through the use of 16 small projections in the vacuum chamber. The projections also improve the stabilization of the cornea to eliminate distortion of the cornea during the trephination cut.
When the trephine is placed on the cornea and vacuum is applied, these projections make slight indentations in the cornea which can then be marked with an accompanying gentian violet ink pen after the trephine is removed from the eye. With the suture points evenly marked around the cornea, the surgeon can minimize astigmatism, which is a common side effect of penetrating keratoplasty.
As with all BPI trephine products, the blade of the Barron Radial Vacuum Trephine 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. Some other manufacturers of vacuum trephines construct their instruments by bending thin (0.1 mm thick) razor blades into a cylinder, a process that results in a non-circular cylinder. Those thin blades are also easily nicked, bent, or chipped. BPI uses a process that was developed to yield quality blades that are uniquely suited for corneal surgery, and are precision machined to yield a perfect circular cylinder that is needed for predictable surgical results. The blades in the BPI trephines are a durable 0.3 mm thick, which provides blades that are less subject to accidental damage that might be caused by the surgeon or assistant during preparation for the operation.
To facilitate optimal location of the trephine as it is positioned on the patient’s eye, fine cross-hairs are incorporated inside each trephine blade. These help physicians to align the trephine with the center of the desired cut. The cross-hairs are positioned in such a way that they are as close to the surface of the cornea as possible without contacting the epithelium.
The blade is then mounted in a spoke adapter that allows the blade to be precisely lowered at a rate of 0.25 mm per each revolution.
An introduction to the use of the Barron Radial Vacuum Trephine
The Barron Radial Vacuum Trephines come in 11 sizes, with blades ranging from 6.0 mm to 9.0 mm in diameter. There are two families of punches that can be used in conjunction with the Radial Vacuum Trephines, the Donor Cornea Punch and the Barron Vacuum Donor Cornea Punch. The punches are available in 0.25 mm diameter increments to provide flexibility in matching donor tissue with the incision made by the trephine. The Barron Radial Vacuum Trephines are only available through Katena Products, Inc. or one of their authorized world-wide distributors. Please contact Katena to place orders for the Radial Vacuum Trephines.