730 - The Hidden Risk of Histotripsy: Imaging Surveillance and Recognition of Complications

Monday, April 13, 2026

4:45 PM - 4:51 PM ET

Author/Co-author(s)

Rebecca Choi, MD

Resident
Johns Hopkins, United States

Abstract Presenter(s)

ZS

Zachary Smith de la Cuesta, MD

Resident
Johns Hopkins Hospital, United States

Author/Co-author(s)

IO

Ifeyinwa Ojukwu, MS

Medical Student
Johns Hopkins School of Medicine, United States
Mark L. Lessne, MD, FSIR

Vascular and Interventional Radiologist
Charlotte Radiology, United States
BH

Brian Holly, MD

Assistant Professor
Johns Hopkins Hospital, United States
Christos Georgiades, MD, PhD

Professor, Director of Interventional Oncology
Johns Hopkins University, United States

Learning Objectives:

Review the principles of histotripsy and its distinct imaging characteristics compared with thermal ablation.

Recognize early and late complications of histotripsy, including residual tumor viability, recurrence, and unintended injury to adjacent structure.

Identify expected post-ablation findings and distinguish them from incomplete or suboptimal treatment on follow-up imaging.

Background: Histotripsy is a novel ultrasound technology that ablates tissue through high-pressure, microsecond pulses that induce cavitation, enabling precise tumor targeting while minimizing collateral injury. Unlike thermal ablation, which allows intraprocedural confirmation of treatment adequacy through temperature monitoring, no reliable method exists to ensure complete tissue destruction during histotripsy. This makes follow-up imaging essential for evaluating treatment response. The imaging appearance after histotripsy differs from other ablation techniques, reflecting its mechanical mechanism. Compared with thermal methods, histotripsy is associated with less post-procedural inflammation, improved lesion resorption, and a distinct temporal evolution of signal intensity (Table). We will also review complications observed after histotripsy, including transient local skin reactions (Figure), suboptimal tumor destruction, and, rarely, paradoxical tumor progression.

Clinical Findings/Procedure Details:

	Histotripsy	Microwave Ablation	Cryoablation
Immediate (Hours)	T1/T2 hypointense; peripheral enhancement only	Non-enhancing core with thin hyperemic rim	Mixed T1/T2; minimal or early enhancement possible
Early (Weeks)	T2-hyperintense as homogenate absorbed	T1 hyperintense necrosis; T2 rim of edema	Shrinking lesion; hypointense rim, thin enhancement
Late (Months)	Lesion resorbs → T2-hypointense scar	Lesion shrinks further → scar/parenchymal defect (low T2/ADC)
Residual/Recurrent	Heterogeneous residual tissue	Nodular contrast enhancement at margin

We will present illustrative postprocedural MR cases demonstrating both successful and adverse outcomes, including an example of a transient skin rash that appeared immediately after treatment and resolved within one week without additional intervention.

Conclusion and/or Teaching Points:

Histotripsy outcomes must be carefully assessed with follow-up imaging, given the lack of reliable intraprocedural confirmation.

Recognizing imaging features of incomplete ablation and complications is critical to guiding further management.

Standardized surveillance protocols are needed to optimize safety and oncologic efficacy.