Treatment planning of intracranial targets on MRI derived substitute CT data
2013 (English)In: Radiotherapy and Oncology, ISSN 0167-8140, E-ISSN 1879-0887, Vol. 108, no 1, 118-122 p.Article in journal (Refereed) Published
BACKGROUND: The use of magnetic resonance imaging (MRI) as a complement to computed tomography (CT) in the target definition procedure for radiotherapy is increasing. To eliminate systematic uncertainties due to image registration, a workflow based entirely on MRI may be preferable. In the present pilot study, we investigate dose calculation accuracy for automatically generated substitute CT (s-CT) images of the head based on MRI. We also produce digitally reconstructed radiographs (DRRs) from s-CT data to evaluate the feasibility of patient positioning based on MR images. METHODS AND MATERIALS: Five patients were included in the study. The dose calculation was performed on CT, s-CT, s-CT data without inhomogeneity correction and bulk density assigned MRI images. Evaluation of the results was performed using point dose and dose volume histogram (DVH) comparisons, and gamma index evaluation. RESULTS: The results demonstrate that the s-CT images improves the dose calculation accuracy compared to the method of non-inhomogeneity corrected dose calculations (mean improvement 2.0 percentage points) and that it performs almost identically to the method of bulk density assignment. The s-CT based DRRs appear to be adequate for patient positioning of intra-cranial targets, although further investigation is needed on this subject. CONCLUSIONS: The s-CT method is very fast and yields data that can be used for treatment planning without sacrificing accuracy.
Place, publisher, year, edition, pages
2013. Vol. 108, no 1, 118-122 p.
magnetic resonance, radiotherapy, treatment planning, dose calculation, substitute CT
Medical Image Processing Radiology, Nuclear Medicine and Medical Imaging Cancer and Oncology
Research subject radiofysik
IdentifiersURN: urn:nbn:se:umu:diva-68958DOI: 10.1016/j.radonc.2013.04.028ISI: 000324155900018PubMedID: 23830190OAI: oai:DiVA.org:umu-68958DiVA: diva2:619141
Included in thesis in manuscript form.2013-05-022013-05-022013-10-17Bibliographically approved