Optical fiber sensors-based temperature distribution measurement in ex vivo radiofrequency ablation with submillimeter resolution.
Radiofrequency thermal ablation (RFTA) induces a high-temperature field in a biological tissue having steep spatial (up to 6°C∕mm) and temporal (up to 1°C∕s) gradients. Applied in cancer care, RFTA produces a localized heating, cytotoxic for tumor cells, and is able to treat tumors with sizes up to 3 to 5 cm in diameter. The online measurement of temperature distribution at the RFTA point of care has been previously carried out with miniature thermocouples and optical fiber sensors, which exhibit problems of size, alteration of RFTA pattern, hysteresis, and sensor density worse than 1 sensor∕cm. In this work, we apply a distributed temperature sensor (DTS) with a submillimeter spatial resolution for the monitoring of RFTA in porcine liver tissue. The DTS demodulates the chaotic Rayleigh backscattering pattern with an interferometric setup to obtain the real-time temperature distribution. A measurement chamber has been set up with the fiber crossing the tissue along different diameters. Several experiments have been carried out measuring the space-time evolution of temperature during RFTA. The present work showcases the temperature monitoring in RFTA with an unprecedented spatial resolution and is exportable to in vivo measurement; the acquired data can be particularly useful for the validation of RFTA computational models.
Università di Pavia, Dipartimento di Ingegneria Civile ed Architettura, via Ferrata 3, 27100 Pavia (PV), Italy.
Edoardo Gino
EG
Macchi
University of Limerick, Optical Fibre Sensors Research Centre, Plassey House, Limerick, Ireland.
Daniele
D
Tosi
Università di Pavia, Dipartimento di Ingegneria Civile ed Architettura, via Ferrata 3, 27100 Pavia (PV), Italy.
Giovanni
G
Braschi
Università di Pavia, Dipartimento di Ingegneria Civile ed Architettura, via Ferrata 3, 27100 Pavia (PV), Italy.
Mario
M
Gallati
Politecnico di Milano, Dipartimento di Meccanica, via La Masa 34, 20158 Milano (MI), Italy.
Alfredo
A
Cigada
Politecnico di Milano, Dipartimento di Meccanica, via La Masa 34, 20158 Milano (MI), Italy.
Giorgio
G
Busca
University of Limerick, Optical Fibre Sensors Research Centre, Plassey House, Limerick, Ireland.
Elfed
E
Lewis
D000818:Animals; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D008099:Liver / Q000502:physiology; D055100:Optical Fibers; D013552:Swine; D013696:Temperature; D062125:Thermometry / Q000295:instrumentation* / Q000379:methods