Journal of Digital Imaging

, Volume 23, Issue 6, pp 780–792

Incorporation of Preprocedural PET into CT-Guided Radiofrequency Ablation of Hepatic Metastases: a Nonrigid Image Registration Validation Study

Authors

  • Peng Lei
    • Department of Diagnostic Radiology and Nuclear Medicine, School of MedicineUniversity of Maryland
    • Fischell Department of BioengineeringUniversity of Maryland
  • Omkar Dandekar
    • Department of Diagnostic Radiology and Nuclear Medicine, School of MedicineUniversity of Maryland
    • Department of Electrical and Computer EngineeringUniversity of Maryland
  • David Widlus
    • Department of Diagnostic Radiology and Nuclear Medicine, School of MedicineUniversity of Maryland
    • Department of Diagnostic Radiology and Nuclear Medicine, School of MedicineUniversity of Maryland
    • Fischell Department of BioengineeringUniversity of Maryland
    • Department of Electrical and Computer EngineeringUniversity of Maryland
Article

DOI: 10.1007/s10278-009-9204-x

Cite this article as:
Lei, P., Dandekar, O., Widlus, D. et al. J Digit Imaging (2010) 23: 780. doi:10.1007/s10278-009-9204-x

Abstract

This study evaluates the accuracy of augmenting initial intraprocedural computed tomography (CT) during radiofrequency ablation (RFA) of hepatic metastases with preprocedural positron emission tomography (PET) through a hardware-accelerated implementation of an automatic nonrigid PET–CT registration algorithm. The feasibility of augmenting intraprocedural CT with preprocedural PET to improve localization of CT-invisible but PET-positive tumors with images from actual RFA was explored. Preprocedural PET and intraprocedural CT images from 18 cases of hepatic RFA were included. All PET images in the study originated from a hybrid PET/CT scanner, and PET–CT registration was performed in two ways: (1) direct registration of preprocedural PET with intraprocedural CT and (2) indirect registration of preprocedural CT (i.e., the CT of hybrid PET/CT scan) with intraprocedural CT. A hardware-accelerated registration took approximately 2 min. Calculated registration errors were 7.0 and 8.4 mm for the direct and indirect methods, respectively. Overall, the direct registration was found to be statistically not distinct from that performed by a group of clinical experts. The accuracy, execution speed, and compactness of our implementation of nonrigid image registration suggest that existing PET can be overlaid on intraprocedural CT, promising a novel, technically feasible, and clinically viable approach for PET augmentation of CT guidance of RFA.

Key words

CTRadiofrequency ablationImage registrationMutual informationPET

Copyright information

© Society for Imaging Informatics in Medicine 2009