Prostate MRI has become the benchmark examination to search for tumor targets, thanks to a multi-parameter protocol, including T2 sequences, diffusions, and T1 with gadolinium injection. A PIRADS prognostic score is performed on the different sequences and if the lesions are at high risk of malignancy (PIRADS 4 and 5), a targeted biopsy is performed. Minimally invasive ablations called focal treatments are developing more and more: HIFU, cryotherapy, laser, etc. Ultrasound remains the most widespread examination due to its availability, but with less sensitivity than MRI. Ablations are performed under ultrasound with fusion of MRI images In order to assess the ablation area under MRI, the measurement of temperature variations appears necessary to verify the effectiveness of ablation and the lesion volume. Temperature maps are feasible in cardiac MRI during radiofrequency. The thermal mapping MRI sequence is performed in cardiac MRI at the IHU in Bordeaux.