Ablative Margin Quantification Using Deformable Versus Rigid Image Registration in Colorectal Liver Metastasis Thermal Ablation: A Retrospective Single-Center Study

Authors

Yuan-Mao Lin
Iwan Paolucci
Jessica Albuquerque Marques Silva
Caleb S O'Connor
Jun Hong
Ketan Y Shah
Mohamed E Abdelsalam
Peiman Habibollahi
Kyle A Jones
Kristy K Brock
Bruno C Odisio

Publication Date

9-1-2024

Journal

European Radiology

Abstract

Purpose: To investigate the correlation of minimal ablative margin (MAM) quantification using biomechanical deformable (DIR) versus intensity-based rigid image registration (RIR) with local outcomes following colorectal liver metastasis (CLM) thermal ablation.

Methods: This retrospective single-institution study included consecutive patients undergoing thermal ablation between May 2016 and October 2021. Patients who did not have intraprocedural pre- and post-ablation contrast-enhanced CT images for MAM quantification or follow-up period less than 1 year without residual tumor or local tumor progression (LTP) were excluded. DIR and RIR methods were used to quantify the MAM. The registration accuracy was compared using Dice similarity coefficient (DSC). Area under the receiver operating characteristic curve (AUC) was used to test MAM in predicting local tumor outcomes.

Results: A total of 72 patients (mean age 57; 44 men) with 139 tumors (mean diameter 1.5 cm ± 0.8 (SD)) were included. During a median follow-up of 29.4 months, there was one residual unablated tumor and the LTP rate was 17% (24/138). The ranges of DSC were 0.96-0.98 and 0.67-0.98 for DIR and RIR, respectively (p < 0.001). When using DIR, 27 (19%) tumors were partially or totally registered outside the liver, compared to 46 (33%) with RIR. Using DIR versus RIR, the corresponding median MAM was 4.7 mm versus 4.0 mm, respectively (p = 0.5). The AUC in predicting residual tumor and 1-year LTP for DIR versus RIR was 0.89 versus 0.72, respectively (p < 0.001).

Conclusion: Ablative margin quantified on intra-procedural CT imaging using DIR method outperformed RIR for predicting local outcomes of CLM thermal ablation.

Clinical relevance statement: The study supports the role of biomechanical deformable image registration as the preferred image registration method over rigid image registration for quantifying minimal ablative margins using intraprocedural contrast-enhanced CT images.

Key points: • Accurate and reproducible image registration is a prerequisite for clinical application of image-based ablation confirmation methods. • When compared to intensity-based rigid image registration, biomechanical deformable image registration for minimal ablative margin quantification was more accurate for liver registration using intraprocedural contrast-enhanced CT images. • Biomechanical deformable image registration outperformed intensity-based rigid image registration for predicting local tumor outcomes following colorectal liver metastasis thermal ablation.

Keywords

Humans, Male, Female, Liver Neoplasms, Colorectal Neoplasms, Retrospective Studies, Middle Aged, Tomography, X-Ray Computed, Margins of Excision, Aged, Treatment Outcome, Adult, Ablation techniques, Colorectal neoplasms, Computed tomography, Image processing, computer assisted, Liver, Ablation techniques, Colorectal neoplasms, Computed tomography, Image processing, computer assisted, Liver

DOI

10.1007/s00330-024-10632-8

PMID

38334762

PMCID

PMC11815991

PubMedCentral® Posted Date

2-12-2025

PubMedCentral® Full Text Version

Author MSS

Published Open-Access

yes