title: Three-dimensional viewing of and dosimetric calculations in Au-198 implants of the prostate.
abstract: A three-dimensional system for dosimetric calculation of radiation from interstitial brachytherapeutic implants was developed and was compared with conventional dosimetry performed with a commercial two-dimensional system. Software programs written for this study enabled the authors to place radioactive sources in the correct reconstructed anatomic locations, compute the isodose distribution around these sources, and display the isodose curves in their correct relationship to anatomic structures. Eight radiation oncologists evaluated the usefulness of both systems. Verification studies in phantoms and in 20 patients with gold-198 implants in the prostate gland showed that the experimental system was very accurate in volume reconstruction, seed localization, isodose distribution, point-dose calculation, and computation of dose-volume histograms. Although the dose depictions in the two systems matched almost exactly, statistically significant differences existed in interpretation of the dosimetric data generated by both systems. For example, the oncologists consistently believed that the dose to the prostate was lower when the three-dimensional system was used (P less than or equal to .0001).
authors.affiliation: Division of Radiation Oncology, University of Iowa College of Medicine, Iowa City.
authors.forename: V N
authors.initials: VN
authors.lastname: Avizonis
authors.forename: D H
authors.initials: DH
authors.lastname: Hussey
authors.forename: K M
authors.initials: KM
authors.lastname: Anderson
authors.forename: S K
authors.initials: SK
authors.lastname: Jani
authors.forename: K S
authors.initials: KS
authors.lastname: Berbaum
mesh_terms: D001918:Brachytherapy; D003196:Computer Graphics; D005069:Evaluation Studies as Topic; D006050:Gold Radioisotopes / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D008961:Models, Structural; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D012984:Software
chemical_list: D006050:Gold Radioisotopes