Fiber optic sensors-based thermal analysis of perfusion-mediated tissue cooling in liver undergoing laser ablation

The current challenge in the field of thermo-ablative treatments of tumors is to achieve a balance between complete destruction of malignant cells and safeguarding of the surrounding healthy tissue. Blood perfusion plays a key role for thermal ablation success, especially in the case of highly vascularized organs like liver. This work aims at monitoring the temperature within perfused swine liver undergoing laser ablation (LA). Temperature was measured through seven arrays of Fiber Bragg Grating sensors (FBGs) around the laser applicator. To mimic reality, blood perfusion within the ex-vivo liver was simulated using artificial vessels. The influence of blood perfusion on LA was carried out by comparing the temperature profiles in two different spatial configurations of vessels and fibers. The proposed setup permitted to accurately measure the heat propagation in real-time with a temperature resolution of 0.1 °C and to observe a relevant tissue cooling near to the vessel up to 65%.