Improved MR-thermometry during hepatic microwave ablation by correcting for intermittent electromagnetic interference artifacts. (March 2020)

• Record Type: Journal Article
• Authors: Lu, Aiming; Woodrum, David A.; Felmlee, Joel P.; Favazza, Christopher P.; Gorny, Krzysztof R.
• Is Part Of: Physica medica. Volume 71(2020)
• Page Start: 100
• Page End: 107
• Publication Date: 2020-03
• Subjects: Microwave ablation -- MRI guided ablation -- Electromagnetic interfere correction -- MR thermometry -- Proton resonance frequency shift; Medical physics -- Periodicals; Biophysics -- Periodicals; Biophysics -- Periodicals; Imagerie médicale -- Périodiques; Radiothérapie -- Périodiques; Rayons X -- Sécurité -- Mesures -- Périodiques; Physique -- Périodiques; Médecine -- Périodiques; 610.153
• DOI: 10.1016/j.ejmp.2020.02.013
• Languages: English
• ISSNs: 1120-1797

Abstract

Highlights: MR thermometry is useful for monitoring MRI-guided microwave ablation but can suffer from intermittent electromagnetic interference. A fast and effective method is proposed to detect and correct for EMI in MR thermometry images during reconstruction. Substantially improved temperature and thermal damage maps have been demonstrated on our clinical hepatic MWA data. Ex vivo tissue sample study shows the correction introduced minimal errors to the temperature maps and thermal damage maps. Abstract: MRI-guided microwave ablation (MWA) is a minimally invasive treatment for localized cancer. MR thermometry has been shown to be able to provide vital information for monitoring the procedure in real-time. However, MRI during active MWA can suffer from image quality degradation due to intermittent electromagnetic interference (EMI). A novel approach to correct for EMI-contaminated images is presented here to improve MR thermometry during clinical hepatic MWA. The method was applied to MR-thermometry images acquired during four MR-guided hepatic MWA treatments using a commercially available MRI-configured microwave generator system. During the treatments MR thermometry data acquisition was synchronized to respiratory cycle to minimize the impact of motion. EMI was detected and corrected using uncontaminated k-space data from nearby frames in k-space. Substantially improved temperature and thermal damage maps have been obtained and the treatment zone can be better visualized. Our ex vivo tissue sample study shows the correction introduced minimal errors to the temperature maps and thermal damage maps.