Medical Device Link.

Originally Published EMDM January/February 2002

SPECIAL REPORT

MEMS: Making Everything Much Simpler

This catheter-tip sensor is immune to interference.

Frequently, physicians performing MIS procedures are required to maneuver around sensitive organs and perform delicate manipulations through a keyhole-sized opening, a challenge that can be further complicated by unwieldy tools. "The instruments [used] are long," says Randall Wolf of Ohio State University (Columbus, OH, USA), explaining the difficulties that surgeons face. "It's like holding a 2-ft-long pencil by the eraser and trying to write your name with it." Increasingly, however, microelectromechanical systems (MEMS) are being included on these devices to provide improved performance.

"More and more, surgeons are recognizing that there is a real need for these kinds of products," says Michele Migliuolo, president of Verimetra Inc. (Pittsburgh, PA, USA), a firm that manufactures MEMS. One such component being developed by Verimetra is a strain gauge for minimally invasive pinchers that indicates how hard a physician is pulling on a suture. "It's hard to tell how much force you're using with these long devices," says Migliuolo, "a problem that often leads to pulling too hard, breaking the knot, and having to start over." Measuring just 100 x 500 µm, the gauge solves this problem by providing an audio or visual output that varies with changes in the gripping force.

Return to Article: Making it Smaller: Manufacturing Minimally Invasive Devices

A fibre-optic pressure sensor that can be imbedded into the tip of a catheter is also making MIS easier for surgeons. Offered by Fiso Technologies (Sainte Foy, QC, Canada), the FOP-M-055-300 sensor measures just 0.55 x 0.5 mm and eliminates many of the problems associated with external invasive and fluid-filled pressure transducers. "Interference is a big challenge for the traditional sensors employed in these kinds of procedures where lasers, electric scalpels, or magnetic resonance imaging are also often used," says Fiso sales and marketing director Jeff Meilleur. "Since this sensor uses a white-light interrogation technique that is immune to these disturbances, however, it gives surgeons a more accurate picture of the situation, allowing them to do a better job." The sensor also eliminates inaccuracies resulting from air bubbles, accidental movement of the flush line, and pressure changes in the surrounding environment.

Copyright ©2002 European Medical Device Manufacturer