Isfahan University of Medical Sciences

Science Communicator Platform

Share By
Evaluating the Effect of Co-Registered Diagnostic Mr Images Based Ct Simulation on Target Volume Delineation and Dose Distribution for Tomotherapy of Rectal Cancer Publisher

Summary: Research shows MRI/CT combo improves cancer treatment precision, reducing harm to healthy organs. #CancerTreatment #MedicalImaging

B Rahmani BARANOOSH ; D Shahbazigahrouei DARYOUSH ; M Roayaei MAHNAZ
Authors

Source: Journal of Biomedical Physics and Engineering Published:2025


Abstract

Background: Magnetic Resonance Imaging (MRI) has become a complementary imaging method for the treatment planning process due to the limitations of Computed Tomography (CT) imaging. Objective: This study aimed to assess the effect of co-registered MRI and CT (MRI/CT)-based target delineation on the dose to the target, small bowel, bladder, and femoral heads during Helical Tomotherapy (HT). Material and Methods: In this cross-sectional prospective study, MRI in a prone position were obtained for 12 patients with rectal cancer at one-day intervals with simulation CT. Following the co-registration process with the deformable algorithm, target volumes are defined. Gross Tumor Volume (GTV), Clinical Target Volume (CTV), and Planning Target Volume (PTV) were delineated for each CT and MRI/CT. Results: GTV, CTV, and PTV mean values were significantly higher in the CTbased target delineation method than those in the MRI/CT-based method. In MRI/ CT-based plans, the mean HI value was significantly lower, and the mean Conformity Index (CI) value was significantly higher than that in CT-based plans. In a small bowl, the most of dosimetric parameters (Dmax, Dmean, D50%, D50%, V40%, and V45%) were significantly higher for the CT-based plans. In the bladder, all dosimetric parameters, except V30%, were statistically higher in CT-based plans. Conclusion: Co-registered MRI/CT-based treatment planning can produce better dose coverage for the target and reduce the delivered dose to the Organs at Risk (OARs) when compared to CT-based planning. © 2025 Elsevier B.V., All rights reserved.
Other Related Docs
9. Optimization of Ct Slice Thickness in 3D-Crt and Imrt Planning of Low Grade Glioma, International Journal of Radiation Research (2021)