MR and CT image fusion for postimplant analysis in permanent prostate seed implants

Results of a dummy run of postimplant dosimetry between multi-institutional centers in prostate brachytherapy with 125I seeds

“…11 Polo et al compared CT-and CT/MRI-based postimplant dosimetry in 21 patients and found that the CT-based prostate volume was higher than the CT/MRIbased volume, which resulted in an underestimation of the CT-based dosimetry. 12 Thus, CT/MRI fusion images may be effective for understanding the anatomy-based imaging contours of the prostate and its adjacent tissues. At present, postimplant dosimetry based on CT/MRI fusion imaging is recommended as a solution to these various issues.…”

CT-based postimplant dosimetry of prostate brachytherapy: comparison of 1-mm and 5-mm section CT

“…2,[4][5][6][7][8][9] Although CT/magnetic resonance imaging (MRI) fusion is the best available tool for visualizing the prostate and seeds, MRI has the disadvantages of high cost and low availability. [11][12][13] For these reasons, CT-based dosimetry is widespread as a preferred modality for postimplant dosimetry owing to its availability, low cost, and the capability of visualizing the prostate and the seeds. The basic methods of CT-based postimplant dosimetry have changed little.…”

NCS Report 20: Dosimetry and quality control of brachytherapy with low-energy photon sources (I-125)

“…In clinical cases the signal voids of seeds and blood vessels are difficult to discriminate and also seeds close to the rectum may be difficult to identify. Therefore some authors recommend to use a combination of CT and MRI to localise the seeds in relation to the prostate and other structures [67][68][69][70][71].…”