Purpose
Previous studies have shown that corneal incision architecture is significant in allowing wounds to self-seal and prevent operative complications. Ultra compact micro vibration motors (MVM) that are ubiquitous in cell phones and other devices can be easily fitted to surgical instruments to provide new modalities in cutting. We designed a device that attaches to microsurgical instruments and generates planar blade oscillations with the goal of improving broad corneal incisions similar to those created during manual small-incision cataract surgery. In this project we analyzed the force required to initiate and maintain an incision as well as incision appearance to determine the effect of outfitting blades with the MVM attachment.
Methods
Ballistic gelatin was used as a tissue analog. The analog was placed into a sample holder outfitted with two Omega strain gauges. The testing frame was fitted with a stepper motor that moved a #5 Beaver blade along a manufactured rail system. Voltage across the strain gage circuit was measured using an oscilloscope. From these measurements, forces required to initiate and maintain an incision were calculated for blades outfitted with the MVM attachment and compared to control blades without the MVM attachment. Once incisions were completed, wound architecture was examined using light microscopy at 80x magnification.
Results
The force required to initiate incisions with the MVM attachment was close to 2.3N compared to 3.5N without vibration. The force exerted during the steady loading portion of the incision was lower with blades fitted with the MVM attachment than those without, indicating that once the incision had been initiated it was easier to maintain. Appearance of ballistic gelatin samples under light microscopy revealed smoother incision margins with vibrating blades than those without.
Conclusions
Outfitting blades with the MVM attachment reduces the force required to initiate and maintain an incision, reducing tissue tension and improving wound appearance. If these results were confirmed with further testing on cornea tissue and more in-depth wound analysis, these findings would suggest a possible role for MVM attachments in improving corneal incision formation and architecture.