NASA-Inspired Shape-Sensing Fibers Enable Minimally Invasive Surgery

Friday, February 01 2008 The grouping of three FBGs at any point in the multi-core fiber's cross-section is referred to as a sensor triplet. The portion of fiber between one sensor triplet and the next is referred to as a tether segment. To determine the optical fiber's shape, we begin at the first sensor triplet and use the strain measurements from each core's FBG to compute the characteristics of the bend at that point. Using this data, the next sensor triplet's location within the optical fiber is extrapolated. By repeating this process for each sensor triplet in the fiber, the overall shape of the fiber can be determined.¹

Beyond Medicine

The global market for minimally invasive surgery (MIS) devices and instruments is expected to reach $18.5 billion by 2011, with average annual growth rate (AAGR) of 7.5% between 2006 and 20112. Incorporating location and position information into the next-generation of devices will enhance the navigation of surgical instruments and improve patient care.

The challenge of determining the dynamic shape and position is of interest outside the medical field such as in aerospace and ocean surveillance. Shape modification of aircraft wings during flight can provide significant performance improvements by matching the aerodynamic shape to flight conditions and by maintaining smooth lifting surfaces without control surface discontinuities. Ocean surveillance ships have a mission to gather underwater acoustical data, including submarine hunting patrols, counter drug missions, and deep water search and rescue. Ships on hunting duty often use towed sonar arrays, which consist of a string of long, flexible modules containing hydrophones that are used to locate underwater noise sources. Shape technology can enhance performance by providing information on the disposition of the flexible cable.

This article was written by Trevor Rice, Business Development Manager for Luna Innovations, Roanoke, VA. For more information, visit here.

References

¹. Characterization of a fiber-optic shape and position sensor (Proceedings Paper) Proceedings Vol. 6167; Smart Structures and Materials 2006: Smart Sensor Monitoring Systems and Applications, Daniele Inaudi; Wolfgang Ecke; Brian Culshaw; Kara J. Peters; Eric Udd, Editors, 616704 Date: 30 March 2006. 2. “Trends in the Noninvasive and Minimally Invasive Medical Device Market”, June 2006, www.piribo.com, Business Communications Company.