Miniaturized Catheter-Integrated Photoacoustic Ablation Monitoring System: A Feasibility Study

Current gold standard approach of radiofrequency ablation (RFA) utilizes computed tomography (CT) and magnetic resonance imaging (MRI) for pre- and post-operative assessments, lacking the real-time monitoring of the ablation process. Photoacoustic (PA) imaging solves this limitation by utilizing a laser-generated real-time functional imaging process, allowing an operator to observe how the ablation process is going. Nevertheless, the PA RFA essentially depends on two separate insertions of the PA imaging technique and the RFA catheter, imposing a challenge in utilizing this technique in muscular tissue. To solve this problem, we present a miniaturized catheter-integrated PA ablation monitoring system for performing the PA RFA in one insertion, where we integrated an ultrasound (US) transducer, an optical fiber, and a RFA into 4 mm in diameter. The proposed miniaturized catheter-integrated PA RFA is evaluated using an ex-vivo porcine cardiac tissue, showing the ablation monitoring by providing temporal ablation extent (AE) feedback at a wide range of PA spectrum scanning. We expect the proposed system will simplify and minimize the complication of the ablation procedure.