Program Information
Comparison of the Delineation of Ablation Regions with Electrode Displacement Elastography and Acoustic Radiation Force Impulse Imaging
W Yang*, T Varghese , T Ziemlewicz , M Alexander , M Lubner , J Hinshaw , S Wells , F Lee Jr , University of Wisconsin, Madison, WI
Presentations
WE-DE-708-4 (Wednesday, August 2, 2017) 10:15 AM - 12:15 PM Room: 708
Purpose: To compare our previously introduced quasi-static ultrasound elastography technique, electrode displacement elastography (EDE), with a dynamic technique, referred to as acoustic radiation force impulse imaging (ARFI), for monitoring the microwave ablation (MWA) procedure for liver tumor with phantom and clinical studies.
Methods: Forty-nine patients diagnosed with either a hepatic carcinoma or metastases were recruited. EDE and ARFI images were acquired using a Siemens Acuson S2000 system for identical imaging locations after a MWA procedure. EDE data was analyzed using a cross-correlation based algorithm and ARFI images were obtained using the built-in ‘Virtual Touch’ function on the system. The size of the ablation inclusion and image quality was compared with 10 independent measurement with two tissue mimicking phantoms.
Results: A comparison study with two observers, indicate that the ablated region on ARFI images was recognizable on an average of 20 patients utilizing B-mode imaging reference, however delineable ablation boundaries could be generated on an average of 4 patients. On the other hand, the ablated region was delineable on an average of 40 patients with EDE, with less imaging depth dependence. Tissue mimicking phantom evaluations show that the ablation region dimensions measured on EDE and ARFI images was within 8%, while the image contrast and contrast to noise ratio with EDE was 2 – 3 times higher than that obtained with ARFI.
Conclusion: The monitoring ability for MWA in terms of delineation rate and contrast to noise ratio was improved with EDE when compared to ARFI on a commercial system. EDE is potentially an alternative imaging modality to provide real-time feedback on the size of the ablation zone, which is a key factor of the treatment outcome of MWA. EDE will be further compared with CT, which is the current gold standard, with an image fusion technique.
Funding Support, Disclosures, and Conflict of Interest: This study was funded by NIH grant 2R01 CA112192.
Contact Email: