In vivo monitoring of microwave ablation in a porcine model using ultrasonic differential attenuation coefficient intercept imaging.

In this study, the feasibility of using ultrasonic differential attenuation coefficient intercept (Δα) imaging to evaluate thermal lesions induced by microwave ablation (MWA) was explored using an in vivo porcine model. The attenuation coefficient intercept (Δα is estimated by subtracting an initial value of Δα images. Receiver operating characteristic (ROC) curves and the area under ROC curve (AUC) were employed to statistically assess the predictability of ultrasonic imaging. Ultrasonic Δα values were approximately 0.13 dB/cm and 0.16 dB/cm in a normal liver and kidney, respectively, increasing to 2.9 dB/cm and 2.55 dB/cm in ablated regions after MWA. The CNR values of the ultrasonic Δα images (0.9 dB and 0.6 dB in the liver and kidney, respectively) were significantly higher (p < 0.05) than the values of B-mode images (0.6 dB and 0.3 dB). The AUC value of the ultrasonic Δα image was higher than the B-mode image value, 0.95 compared with 0.88. This in vivo study suggests that ultrasonic Δα imaging has the potential to evaluate thermal lesions with high accuracy and better image contrast for monitoring MWA.