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

Abstract

In this study, the feasibility of using ultrasonic differential attenuation coefficient intercept (Δα 0 ) imaging to evaluate thermal lesions induced by microwave ablation (MWA) was explored using an in vivo porcine model. The attenuation coefficient intercept (Δα 0 is estimated by subtracting an initial value of Δα 0 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 0 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 0 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 0 image was higher than the B-mode image value, 0.95 compared with 0.88. This in vivo study suggests that ultrasonic Δα 0 imaging has the potential to evaluate thermal lesions with high accuracy and better image contrast for monitoring MWA.