TY - JOUR
T1 - Ultrasound-fluoroscopy registration for prostate brachytherapy dosimetry
AU - Dehghan, Ehsan
AU - Lee, Junghoon
AU - Fallavollita, Pascal
AU - Kuo, Nathanael
AU - Deguet, Anton
AU - Le, Yi
AU - Clif Burdette, E.
AU - Song, Danny Y.
AU - Prince, Jerry L.
AU - Fichtinger, Gabor
N1 - Funding Information:
Ehsan Dehghan was supported by an Ontario Ministry of Research and Innovation post-doctoral fellowship . Gabor Fichtinger was supported as Cancer Care Ontario Research Chair . This work was also supported by National Institutes of Health/National Cancer Institute (NIH/NCI) under Grants 2R44CA099374 and 1R01CA151395 , and by the Idea to Innovation Program of the Natural Sciences and Engineering Research Council of Canada .
PY - 2012/10
Y1 - 2012/10
N2 - Prostate brachytherapy is a treatment for prostate cancer using radioactive seeds that are permanently implanted in the prostate. The treatment success depends on adequate coverage of the target gland with a therapeutic dose, while sparing the surrounding tissue. Since seed implantation is performed under transrectal ultrasound (TRUS) imaging, intraoperative localization of the seeds in ultrasound can provide physicians with dynamic dose assessment and plan modification. However, since all the seeds cannot be seen in the ultrasound images, registration between ultrasound and fluoroscopy is a practical solution for intraoperative dosimetry. In this manuscript, we introduce a new image-based nonrigid registration method that obviates the need for manual seed segmentation in TRUS images and compensates for the prostate displacement and deformation due to TRUS probe pressure. First, we filter the ultrasound images for subsequent registration using thresholding and Gaussian blurring. Second, a computationally efficient point-to-volume similarity metric, an affine transformation and an evolutionary optimizer are used in the registration loop. A phantom study showed final registration errors of 0.84 ± 0.45. mm compared to ground truth. In a study on data from 10 patients, the registration algorithm showed overall seed-to-seed errors of 1.7 ± 1.0. mm and 1.5 ± 0.9. mm for rigid and nonrigid registration methods, respectively, performed in approximately 30. s per patient.
AB - Prostate brachytherapy is a treatment for prostate cancer using radioactive seeds that are permanently implanted in the prostate. The treatment success depends on adequate coverage of the target gland with a therapeutic dose, while sparing the surrounding tissue. Since seed implantation is performed under transrectal ultrasound (TRUS) imaging, intraoperative localization of the seeds in ultrasound can provide physicians with dynamic dose assessment and plan modification. However, since all the seeds cannot be seen in the ultrasound images, registration between ultrasound and fluoroscopy is a practical solution for intraoperative dosimetry. In this manuscript, we introduce a new image-based nonrigid registration method that obviates the need for manual seed segmentation in TRUS images and compensates for the prostate displacement and deformation due to TRUS probe pressure. First, we filter the ultrasound images for subsequent registration using thresholding and Gaussian blurring. Second, a computationally efficient point-to-volume similarity metric, an affine transformation and an evolutionary optimizer are used in the registration loop. A phantom study showed final registration errors of 0.84 ± 0.45. mm compared to ground truth. In a study on data from 10 patients, the registration algorithm showed overall seed-to-seed errors of 1.7 ± 1.0. mm and 1.5 ± 0.9. mm for rigid and nonrigid registration methods, respectively, performed in approximately 30. s per patient.
KW - Fluoroscopy
KW - Prostate Brachytherapy
KW - Registration
KW - Ultrasound
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U2 - 10.1016/j.media.2012.06.001
DO - 10.1016/j.media.2012.06.001
M3 - Article
C2 - 22784870
AN - SCOPUS:84866463028
SN - 1361-8415
VL - 16
SP - 1347
EP - 1358
JO - Medical image analysis
JF - Medical image analysis
IS - 7
ER -