Fiber optic extrinsic Fabry-Perot interferometry pressure sensors for in-vivo urodynamic analysis

We report a fiber-optic sensing system based on Extrinsic Fabry-Perot Interferometry (EFPI), for pressure detection in medical applications. The system allows dual channel detection, with probes having typical sensitivity of 1.3 nm/kPa and accuracy of 0.6 cmH2O, diameter of 0.2 mm, and perfect biocompatibility. Pressure probes have been applied to urodynamic analysis, measuring both bladder and abdominal pressure. Measurements have been carried out in-vivo on seven patients having different bladder conditions. The fiber-optic probes have been compared with a PICO2000 urodynamic instrument, showing improved accuracy, a good reproduction of bladder-related events, and increased responsivity to local pressure variations.