
Medical & Biotechnology
The human body presents environmental challenges no less demanding than that of space or energy. IFOS has developed a technology platform for instrumenting needles and catheters for use in image-assisted biopsies and surgery. The integration of very small fiber Bragg gratings within the structure of surgical tools provides real- time shape, tip position, tip force, and other measurements that are superimposed on the platform console. The materials are MRI-compatible so that the smart surgical instruments can be used whether the imaging and guidance platform is ultrasound, CT, or MRI based. The measurement of instrument tip position, force, temperature, and shape enhances the ability of the surgeon to perform precision minimally invasive procedures. This results in better patient outcomes and clinical economics.
In a collaboration involving a team of world class researchers and engineers at IFOS, Stanford University’s Mechanical Engineering Department, and the Stanford School of Medicine and Hospital, an MRI-compatible biopsy needle has been developed that can be actively steered using light. A laser source delivers light along a fiber, which in turn provides energy that causes a memory alloy to bend in a controlled fashion, thus allowing the needle a degree of freedom for optical steering. IFOS sensorized medical device technology for biopsy and surgery under the MEDIFOS™ trade name is commercialized by our sister company Opterro.

Medisense™ Smart Surgical Instruments
The high-resolution strain measurement capability of FBGs monitoring by IFOS’s interrogator technology enables intelligent configurations of sensors to perform real-time 3D shape determination. IFOS has demonstrated this capability in ultra-fine (< 1-mm O.D.) biopsy needles whose performance was tested in MRI-guided animal tests at Stanford University.
The slightest strain at any of four points along the needle will cause various shifts in the 12 monitored wavelengths (three FBGs per sensing point). Given the overall geometry of the needle, this information can be algorithmically correlated to the exact shape of the needle with very high precision.
The SteerSense needle tip has high dexterity, which resolves the need for further manipulation of the shaft, such as the rotation used in passive steering. Since our steering mechanism does not have to be removed during the procedure, users can maintain real-time and full control of positioning during the needle-based procedures.