Usefulness of Virtual Expiratory CT Images to Compensate for Respiratory Liver Motion in Ultrasound/CT Image Fusion: A Prospective Study in Patients with Focal Hepatic Lesions
- Author:
Tae Wook KANG
1
;
Min Woo LEE
;
Dong Ik CHA
;
Hyun Jung PARK
;
Jun Sung PARK
;
Won Chul BANG
;
Seon Woo KIM
Author Information
- Publication Type:Original Article
- Keywords: Ultrasonography; Computed tomography; Fusion imaging; Liver; Respiration
- MeSH: Ethics Committees, Research; Humans; Informed Consent; Liver; Prospective Studies; Respiration; Ultrasonography; Weights and Measures
- From:Korean Journal of Radiology 2019;20(2):225-235
- CountryRepublic of Korea
- Language:English
- Abstract: OBJECTIVE: To assess whether virtual expiratory (VE)-computed tomography (CT)/ultrasound (US) fusion imaging is more effective than conventional inspiratory (CI)-CT/US fusion imaging for hepatic interventional procedures. MATERIALS AND METHODS: This prospective study was approved by the Institutional Review Board, and informed consent was obtained from each patient. In total, 62 patients with focal hepatic lesions referred for hepatic interventional procedures were enrolled. VE-CT images were generated from CI-CT images to reduce the effects of respiration-induced liver motion. The two types of CT images were fused with real-time US images for each patient. The operators scored the visual similarity with the liver anatomy upon initial image fusion and the summative usability of complete image fusion using the respective five-point scales. The time required for complete image fusion and the number of point locks used were also compared. RESULTS: In comparison with CI-CT/US fusion imaging, VE-CT/US fusion imaging showed significantly higher visual similarity with the liver anatomy on the initial image fusion (mean score, 3.9 vs. 1.7; p < 0.001) and higher summative usability for complete image fusion (mean score, 4.0 vs. 1.9; p < 0.001). The required time (mean, 11.1 seconds vs. 22.5 seconds; p < 0.001) and the number of point locks (mean, 1.6 vs. 3.0; p < 0.001) needed for complete image fusion using VE-CT/US fusion imaging were significantly lower than those needed for CI-CT/US fusion imaging. CONCLUSION: VE-CT/US fusion imaging is more effective than CI-CT/US fusion imaging for hepatic interventional procedures.