Microsurgical Instruments: Magnifying surgeon’s sense of touch

George Stetten, MD, PhD Bioengineering PI
Professor of Bioengineering
Research Professor, CMU Robotics Institute
Director of the Visualization and Image Analysis (VIA)
Laboratory and the Music Engineering Laboratory (MEL)
Joel S. Schuman, MD, FACS Clinical PI
Eye & Ear Foundation Professor and Chairman,
Department of Ophthalmology
Director of UPMC Eye Center
Professor of Bioengineering
Glaucoma Service

A need exists for improving the perception of forces by touch when using tools to perform delicate surgical procedures. This is especially crucial in ophthalmology, where structures are cut and manipulated using only visual feedback while under a stereo microscope, without appreciable tactile sensation. Providing an enhanced sense of touch at the point of tissue contact would improve outcome and safety. The Hand-Held Force Magnifier (HHFM) aims to provide the sense of touch to a surgeon performing microsurgical procedures.

The HHFM is hand-held tool that contains a sensor to measure small forces between the tip of the tool and the tissue. This signal is amplified to produce larger forces on the handle in the same direct ion, using an actuator mounted on the back of the hand. The operator thus provides a moving platform against which these magnified forces are generated. The end result is that tissues feel stiffer than they really are, and small forces can be better controlled.