Overlapped seed localization in seed implant brachytherapy.

A procedure for the determination of the location of prostate implant seeds that are wholly overlapped in a projection view has been developed. The procedure mainly consists of a series of image processing and an in-house developed localization software based on a three-film technique. To verify the efficacy of the procedure, a simulation phantom was built and nine sets of simulation were performed. For the assessment of the location of the seeds in the phantom, three images, one in anterior-posterior direction and two others in oblique angles, were acquired and a series of image processing was applied to the images for the removal of unnecessary background and the improvement of imaging quality. In this study, three types were considered; first, when two seeds were overlapped in one of projection images, second, more than three seeds were overlapped in one of projection images, and the third, all images contained wholly overlapped seeds. The developed software separates wholly overlapped seeds by calculating the distance between seeds in each film. This software can provide valuable information for establishing effective quality assurance in permanent prostate brachytherapy.

[1]  Ismail B. Tutar,et al.  Tomosynthesis-based localization of radioactive seeds in prostate brachytherapy. , 2003, Medical physics.

[2]  D H Brinkmann,et al.  Automated seed localization from CT datasets of the prostate. , 1998, Medical physics.

[3]  R. Marks,et al.  Three-dimensional seed reconstruction from an incomplete data set for prostate brachytherapy. , 2004, Physics in medicine and biology.

[4]  J J Prete,et al.  Source localization from axial image sets by iterative relaxation of the nearest neighbor criterion. , 1999, Medical physics.

[5]  M D Altschuler,et al.  Rapid, accurate, three-dimensional location of multiple sees in implant radiotherapy treatment planning. , 1983, Physics in medicine and biology.

[6]  John D. Austin,et al.  Adaptive histogram equalization and its variations , 1987 .

[7]  D. D'Souza,et al.  Intra-operative dosimetry of trans-rectal ultrasound guided 125I prostate implants using C-arm fluoroscopic images , 2006, Journal of medical physics.

[8]  D Tubic,et al.  Automated seed detection and three-dimensional reconstruction. I. Seed localization from fluoroscopic images or radiographs. , 2001, Medical physics.

[9]  H I Amols,et al.  A three-film technique for reconstruction of radioactive seed implants. , 1981, Medical physics.

[10]  D D Jackson.  An automatic method for localizing radioactive seeds in implant dosimetry. , 1983, Medical physics.

[11]  D Tubic,et al.  Automated seed detection and three-dimensional reconstruction. II. Reconstruction of permanent prostate implants using simulated annealing. , 2001, Medical physics.

[12]  N Pallikarakis,et al.  Three-dimensional localisation based on projectional and tomographic image correlation: an application for digital tomosynthesis. , 1999, Medical engineering & physics.

[13]  Xinhua Zhuang,et al.  Image Analysis Using Mathematical Morphology , 1987, IEEE Transactions on Pattern Analysis and Machine Intelligence.

[14]  R. Robb,et al.  Prostate brachytherapy seed localization by analysis of multiple projections: identifying and addressing the seed overlap problem. , 2004, Medical physics.

[15]  Blasko,et al.  10-year biochemical (prostate-specific antigen) control of prostate cancer with (125)I brachytherapy. , 2001, International journal of radiation oncology, biology, physics.

[16]  C C Ling,et al.  A CT-based evaluation method for permanent implants: application to prostate. , 1993, International journal of radiation oncology, biology, physics.

[17]  R. Marks,et al.  Three-dimensional seed reconstruction for prostate brachytherapy using Hough trajectories , 2004, Physics in medicine and biology.

[18]  N. Otsu.  A threshold selection method from gray level histograms , 1979 .

[19]  M S Rosenthal,et al.  An automatic seed identification technique for interstitial implants using three isocentric radiographs. , 1983, Medical physics.

[20]  Paul S Cho,et al.  Fast cross-projection algorithm for reconstruction of seeds in prostate brachytherapy. , 2002, Medical physics.