Distributed fiber-optic sensors for thermal monitoring in radiofrequency thermal ablation in porcine phantom

In this paper, we report for the first time the application of two distributed fiber-optic sensing systems in medical radiofrequency thermal ablation (RFTA). Measurement systems are based on a distributed temperature sensor based on high-speed detection of Rayleigh signature, and a linearly chirped fiber Bragg grating (LCFBG) sensor that detects temperature distribution on 1.5 cm length. Both technologies are capable of achieving sub-0.1mm spatial resolution. The sensing systems have been applied to monitor the temperature pattern induced by RFTA, measuring temperature gradients in excess of 5 degrees C/mm. All tests have been performed on porcine liver tissue, the phantom of human liver. The results show the premises for the realization of a distributed sensor installed on a RFTA device, capable of real-time prediction and estimation of the ablation effect.