|There are two imaging modalities integrated with HIFU to detect the region-of-interest: ultrasound and MRI. Ultrasound imaging uses the same energy modality and pathway as therapeutic pulse for HIFU ablation guidance and lesion monitoring, so unsatisfactory acoustic coupling or blocking by ribs or other organs could be identified. Despite the low cost and easy integration of ultrasound diagnostic system, the image quality itself may not be sufficient to detect solid tumor/cancer without registration with other diagnosis information (i.e., CT, MRT and PET). In contrast, MRI has excellent anatomical resolution and high sensitivity for tumor detection, offering accurate planning of the tissue to be targeted, itâs bulky, expensive and operation complicated. Thereby current temperature monitoring technique for HIFU ablation is based on either ultrasound or MRI. [Zhou Y (2011) Thermography in High-Intensity Focused Ultrasound Ablation].