Multiatlas Fusion with a Hybrid CT Number Correction Technique for Subject-Specific Pseudo-CT Estimation in the Context of MRI-Only Radiation Therapy |
| |
| Affiliation: | 1. Department of Informatics, Ferhat Abbas University, Sétif, Algeria;2. IEMN, UMR CNRS 8520, Department OAE, University of Valenciennes and Hainaut-Cambresis, UVHC, Valenciennes, France;3. Department of Radiotherapy, Institut Curie - Hôpital René Huguenin Saint-Cloud, France;1. Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, ON, Canada;2. Department of Radiation Therapy, Sunnybrook Odette Cancer Centre, University of Toronto, ON, Canada;3. Department of Oncology Nursing, Sunnybrook Odette Cancer Centre, University of Toronto, ON, Canada;4. Patient and Family Education Program, Sunnybrook Odette Cancer Centre, University of Toronto, ON, Canada;5. Department of Oncology, Queen''s University, Kingston, ON, Canada;1. Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil;2. Fundação Pró-Sangue/Hemocentro of São Paulo, Molecular Biology Department, São Paulo, Brazil;3. Infectious Disease Division (DIPA), Federal University of São Paulo, São Paulo, Brazil;1. Vanderbilt University School of Medicine, Nashville, Tennessee, USA;2. Department of Radiation Oncology, Vanderbilt University Medical Center, Nashville, Tennessee, USA;3. Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA;1. McMaster University, Faculty of Science, Hamilton, Ontario, Canada;2. Tom Baker Cancer Centre, Radiation Therapy Department, Calgary, Alberta, Canada;3. Juravinski Cancer Centre, Radiation Therapy/Medical Physics Department, Hamilton, Ontario, Canada |
| |
| Abstract: | ObjectiveTo propose a hybrid multiatlas fusion and correction approach to estimate a pseudo–computed tomography (pCT) image from T2-weighted brain magnetic resonance (MR) images in the context of MRI-only radiotherapy.Materials and MethodsA set of eleven pairs of T2-weighted MR and CT brain images was included. Using leave-one-out cross-validation, atlas MR images were registered to the target MRI with multimetric, multiresolution deformable registration. The subsequent deformations were applied to the atlas CT images, producing uncorrected pCT images. Afterward, a three-dimensional hybrid CT number correction technique was used. This technique uses information about MR intensity, spatial location, and tissue label from segmented MR images with the fuzzy c-means algorithm and combines them in a weighted fashion to correct Hounsfield unit values of the uncorrected pCT images. The corrected pCT images were then fused into a final pCT image.ResultsThe proposed hybrid approach proved to be performant in correcting Hounsfield unit values in terms of qualitative and quantitative measures. Average correlation was 0.92 and 0.91 for the proposed approach by taking the mean and the median, respectively, compared with 0.86 for the uncorrected unfused version. Average values of dice similarity coefficient for bone were 0.68 and 0.72 for the fused corrected pCT images by taking the mean and the median, respectively, compared with 0.65 for the uncorrected unfused version indicating a significant bone estimation improvement.ConclusionA hybrid fusion and correction method is presented to estimate a pCT image from T2-weighted brain MR images. |
| |
| Keywords: | Pseudo-CT MR-only radiotherapy brain hybrid CT number correction multiatlas fusion |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
