Homogeneous catheter for esophagus high-resolution manometry using fiber Bragg gratings

摘要

The high resolution manometry of the upper gastrointestinal tract is moving from research into clinical practice [1], [2]. Hence, there is a need for easy to use and patient friendly diagnosis devices for high resolution esophagus manometry. Besides established methods like perfusion manometry and solid state sensor manometry the use of optical fiber sensor catheters based on fiber Bragg gratings (FBGs) is gaining interest among physicians and medical equipment manufacturers [3], [4]. This paper presents design, prototyping and characterization of a fiber Bragg grating pressure sensor catheter. It uses a two layer polymer coating for the transformation of radial forces into axial strain of the optical fiber. The sensitivity with respect to pressure is in the range of 1 mmHg, the spatial resolution is provided by 32 sensors with a pitch of 10 mm. The coating technique is scalable to smaller diameters down to 0.5 mm and the flexibility isrnhomogeneous over the whole length and can be adjusted by the choice of the coating materials.