Reduction of respiratory motion effect on histotripsy ablation in porcine liver models by use of jet ventilation

Monday, March 6, 2023

12:00 PM – 1:00 PM

Location: Phoenix Convention Center, North Ballroom 120 D

Poster Presenter(s)

JW

John E. Winterholler, MD (he/him/his)

Resident Physician, Interventional Radiology
UW Hospitals and Clinics

Disclosure(s): No financial relationships to disclose

Author/Co-author(s)

Meridith A. Kisting, MA

Research Assistant
University of Wisconsin Hospitals and Clinics
Katrina L. Falk, MS (she/her/hers)

Graduate Research Fellow
University of Wisconsin Madison
AK

Adrienne L. Kisting, BS

Research Assistant
University of Wisconsin
JW

Jim White, BME

Lab Manager
University of Wisconsin - Madison
ML

Meghan Lubner, MD

Professor
University of Wisconsin - Madison
Paul F. Laeseke, MD, PhD

Assistant Professor
University of Wisconsin
LM

Lori Mankowski-Gettle, MD, MBA

Associate Professor
University of Wisconsin Hospitals and Clinics
LS

Lindsay Stratchko, DO

Assistant Professor
University of Wisconsin
JS

John F. Swietlik, MD

Assistant Professor
University of Wisconsin
JH

J. Louis Hinshaw, MD

Professor
University of Wisconsin School of Medicine and Public Health
TF

Tatiana Ferreira, DVM, PhD

Associate Professor
University of Wisconsin
TM

Timothy McCormick, DO

Assistant Professor
University of Wisconsin
FL

Fred T. Lee, Jr., MD

Professor of Radiology, Biomedical Engineering, and Urology
University Of Wisconsin
Timothy J. Ziemlewicz, MD

Associate Professor of Radiology
University of Wisconsin Hospital and Clinics

Disclosure(s):

John E. Winterholler, MD: No financial relationships to disclose

Meridith A. Kisting, MA: No financial relationships to disclose

Lindsay Stratchko, DO: Elucent Medical, Inc: Shareholder (Ongoing)

Fred T. Lee, MD, Jr.: Canon Medical Inc., Medical Advisory Board: Board Membership (Ongoing), Contracted Research (Ongoing); Ethicon, Inc.,: Consultant (Ongoing); Histosonics, Inc.: Board Membership (Ongoing), Contracted Research (Ongoing); Medtronic Inc.,: Intellectual Property Rights (Ongoing), Royalties (Ongoing)

Timothy J. Ziemlewicz, MD: Elephas: Advisory Committee or Review Panel Member (Ongoing), Consultant (Ongoing); Histosonics Inc.: Ownership Interest (Ongoing), Research Grant Recipient (Ongoing); J&J / Ethicon / NeuWave: Consultant (Ongoing), Research Grant Recipient (Ongoing); Medical Engineering Innovations: Ownership Interest (Ongoing), Salaried Employee (Ongoing)

Purpose: Histotripsy is a non-invasive, non-thermal, non-ionizing local treatment modality which is currently in clinical trials for the treatment of liver tumors. In contrast to thermal ablation methods, histotripsy uses externally applied ultrasound energy, subjecting it to respiratory motion effects resulting in elongation of the craniocaudal dimension of the treatment zone in prior studies. Jet ventilation is an anesthesia technique which allows decreased hepatic motion due to low tidal volume and rapid rate. The purpose of this study was to evaluate if using jet ventilation as compared with conventional ventilation can result in decreased craniocaudal dimension of histotripsy treatment zones.

Materials and Methods: Six female swine underwent two 2.5 cm sphere hepatic histotripsy treatments, one each with jet ventilation (JV) and conventional ventilation (CV) (12 total treatment zones). Whether JV or CV were performed first and laterality of treatments were alternated between animals. Histotripsy (Histosonics, Inc.) and JV (Monsoon III, Acutronic Medical Systems) were performed with clinical grade systems. Post procedural magnetic resonance imaging (MRI) was obtained immediately following ablation and antero-posterior (AP), transverse (Trv), and craniocaudal (CC) dimensions of each zone measured in the portal venous phase. Volume was calculated using an ellipsoid formula (L x W x H x π/6). Livers were harvested for pathologic analysis.

Results: The mean CC length of the JV treatment, 2.8 (standard deviation 0.3) cm was significantly shorter than the CV treatment, 3.6 (0.3) cm, p< 0.05. AP and Trv dimensions were not significantly different between JV, 3.2 (0.5) x 2.5 (0.3) cm, and CV, 2.8 (0.3) x 2.8 (0.2) cm, p=0.25 and 0.28, respectively. There was no difference in volume of treatment zones between JV, 12.0 (4.4) mL and CV, 14.6 (2.1) mL, p=0.25. Pathologic analysis is pending to evaluate differences in transition zones from treated to normal tissue between ventilation modalities.

Conclusion: Jet ventilation during histotripsy reduces respiratory motion effect in the craniocaudal dimension which has the potential to improve the precision of histotripsy.