Four-Dimensional Optoacoustic Temperature Mapping In Laser-Induced Thermotherapy

Photoablative laser therapy is in common use for selective destruction of malignant masses, vascular and brain abnormalities. Tissue ablation and coagulation are irreversible processes occurring shortly after crossing a certain thermal exposure threshold. As a result, accurate mapping of the temperature field is essential for optimizing the outcome of these clinical interventions. Here we demonstrate four-dimensional optoacoustic temperature mapping of the entire photoablated region. Accuracy of the method is investigated in tissue-mimicking phantom experiments. Deviations of the volumetric optoacoustic temperature readings provided at 40ms intervals remained below 10% for temperature elevations above 3 degrees C, as validated by simultaneous thermocouple measurements. The excellent spatio-temporal resolution of the new temperature monitoring approach aims at improving safety and efficacy of laser-based photothermal procedures.