Twenty-three and 25-gauge forceps can be more difficult to use than 20-gauge forceps. Illumination and vitrectomy devices have been optimized for cannula-based surgery procedures leaving, an opening for improvements to the instrumentation. The smaller-gauge instruments must be designed within a smaller envelope determined by the cannula's inner diameter. The smaller tip profiles create stress concentrations, which make grasping and holding internal membranes more difficult, often leading to tearing or shredding. This presents several problems, including making it more difficult to complete the membrane peel and potentially leading to longer surgical time.

Most microsurgical instruments currently available are scaled-down versions of their 20-gauge forefathers. Very few instruments have been specifically designed with the smaller gauges in mind. There are many benefits to the smaller gauge surgery. Smaller tips allow the user better visualization and increase ability to grab fine membranes with less risk. There is also a reduction in surgical time because there is no need to suture at the end of the case. In cooperation with Synergetics, Inc. (O'Fallon, MO), I have designed new forceps that mimic attributes of 20-gauge instruments while allowing the benefits of the smaller gauges to be maintained.

INSTRUMENT DESIGN
The Apte Corset forceps (Synergetics, Inc.) are different from other forceps in that they are wider at the tip, allowing for a larger grasping platform (Figures 1 and 2). The larger platform distributes the closing force of the jaws over a greater area, reducing pressure points on the membrane that lead to tearing (Figure 3). The platforms are covered with a patented microserration technology that gives the jaws a structured surface finish, allowing for better membrane grasping. The tip has an hourglass profile, optimizing the visualization at the tip (Figures 2 and 4). The tip and shaft are blackened to reduce glare (Figure 4). The proximal end of the forceps is widened to provide stability in closing and improve the lifespan and durability of the instrument. All sharp outer edges of the instrument are rounded over to reduce the chance of retinal damage. The resulting forceps are versatile and are usable for peeling both fine internal limiting membrane and thicker diabetic membranes.

Rajendra S. Apte, MD, PhD, is an Assistant Professor and Director of Education, Ophthalmology and Visual Sciences, and Developmental Biology at the Barnes Retina Institute, Washington University School of Medicine. Dr. Apte reports that he is a consultant for Synergetics, Inc. He can be reached at +1 314 747 5262; fax: +1 314 362 6793; or via e-mail at apte@vision.wustl.edu.