259 - MRI Appearance of Vascular Malformations After Cryoablation

Tuesday, April 14, 2026

3:27 PM - 3:36 PM ET

Presenting Author(s)

KC

Ke Chen, MD

Interventional radiologist
United Health Network, Canada

Author/Co-author(s)

AQ

Aziz Qazi, MD

Vascular and Interventional Radiologist
University of Toronto, University Health Network, Canada
SL

Sean Lau, BSc, MSc

Research Coordinator
University Health Network, Canada

Purpose: Cryoablation is an increasingly used technique for the treatment of soft tissue vascular malformations. MRI is the preferred modality for post-treatment evaluation, but descriptions of expected imaging findings remain limited. The objective of this study is to describe MRI findings of vascular malformations after cryoablation and highlight characteristic imaging patterns.

Materials and Methods: From January 2023 through March 2025, 58 patients with vascular malformations underwent cryoablation using a standard protocol. Twenty patients (34%) had pre- and post-procedural MRI follow-up. MRI protocol includes T1 and T2 fat saturated sequences, followed by gadolinium contrast enhanced sequences. Lesions were evaluated for changes in size, T2 signal, contrast enhancement, and associated tissue findings. Follow up imaging was done between 2- and 17-months post-procedure (median of 7 months).

Results: At follow-up MRI, 15 out of 20 patients (75%) demonstrated size reduction: 3 decreased over 50% (15%), 11 decreased less than 50% (55%), and 1 completely regressed (5%). Four lesions (20%) remained stable in size, and one lesion (5%) increased in size. T2 signal decreased or appeared wispier in 6 patients (30%), while 14 (70%) remained stable. Enhancement decreased or appeared wispier in 6 patients (30%), was unchanged in 10 (50%), increased in 1 (5%), and showed complete resolution in 1 (5%). Ancillary findings included adjacent muscle T2 hypersignal in 5 patients (25%).

Conclusion: MRI of vascular malformations after cryoablation most frequently demonstrates partial size reduction (75%), decreased or wispier T2 signal (30%), and stable enhancement pattern (50%). Adjacent muscle hypersignal is a common ancillary finding (25%) and is an expected post-procedural change. These results provide a practical reference for the expected range of post treatment imaging appearances.