Print Email Facebook Twitter Flexible Sensors for Minimally Invasive Medical Instruments Title Flexible Sensors for Minimally Invasive Medical Instruments Author Mimoun, B.A.Z. Contributor Dekker, R. (promotor) Faculty Electrical Engineering, Mathematics and Computer Science Department ECTM Date 2013-04-22 Abstract Being able to measure medical parameters directly inside the body in a minimally invasive way allows for a more accurate, faster, safer and cheaper diagnosis. A typical example can be found in the diagnosis of coronary artery diseases, where simultaneous measurement of intracoronary blood flow and pressure is needed. The aim of this Thesis is to provide the technological means to implement diverse sensing functionalities, such as pressure and flow sensing, at the tip of minimally invasive medical instruments. Because of the cylindrical shape and the small diameter of catheters and guidewires (Ø = 1 mm and 360 µm, respectively), it is almost unavoidable that complex sensing/and or electronics systems must include flexible or foldable parts. FleXss, a Matlab-based graphical user interface was created. It allows a quick and easy analytical modeling of the stress-strain distribution in multilayered devices during and after fabrication, with the possibility to apply external bending. A generic technological platform allowing for the design, fabrication and assembly of partially flexible sensor systems at the tip of minimally invasive medical instruments was also developed. The Flex-to-Rigid (F2R) technology specifically addresses the handling and mounting issues arising when working with small, ultra-flexible devices. Moreover, the fabrication of ultra-flexible sensors requires the opening of high density vias in polyimide coatings. A two-step plasma etching recipe combining both isotropic and anisotropic profiles, resulting in residue-free wine glass shaped vias, was developed. The design of a polyimide-based 5 mm diameter flexible calorimetric flow sensor was optimized in order to fit around a medical guidewire. It was possible to successfully bend the improved flow sensor around a 360 µm wire, by keeping in the tensile plane only structures that are small compared to the bending diameter. All structures that are oriented perpendicular to the bending axis are embedded in the stress neutral plane. Numerical studies showed that the performance of the mechanically improved sensor is similar to the less flexible original device. It was moreover experimentally proven that the constant temperature sensor driving mode is superior to the constant power mode in terms of sensitivity and applicability for in-vivo use. Subject flexible devicesmedical instrumentspolyimidemultilayered devices reliabilitythermoelectric flow sensors To reference this document use: https://doi.org/10.4233/uuid:767547aa-1cd6-40cc-b9d6-95a3d6bbc1db Publisher CPI Wohrmann Print Services ISBN 9789462033368 Part of collection Institutional Repository Document type doctoral thesis Rights (c) 2013 Mimoun, B.A.Z. Files PDF Thesis_BMimoun_FINAL_NOCOVER.pdf 107.96 MB Close viewer /islandora/object/uuid:767547aa-1cd6-40cc-b9d6-95a3d6bbc1db/datastream/OBJ/view