title: Single-energy metal artifact reduction in postimplant computed tomography for I-125 prostate brachytherapy: Impact on seed identification.
abstract: To evaluate the effectiveness of the single-energy metal artifact reduction (SEMAR) technique for improving the accuracy of I-125 seed identification in postimplant computed tomography (CT) after prostate brachytherapy.
  
  
  
  Postimplant CT images of 40 patients treated with I-125 prostate brachytherapy were acquired. For all patients, 2 data sets were reconstructed, 1 with SEMAR algorithms (SEMAR image), and the other without SEMAR algorithms (non-SEMAR image). Seed locations are automatically detected by the automatic seed finder tool, and their locations were compared between the SEMAR and non-SEMAR images. Dosimetric parameters using seed locations as detected were compared.
  
  
  
  The true-positive fraction of properly detected seeds on the SEMAR image as determined from a reference seed distribution defined by one investigator was significantly higher than the true-positive fraction on the non-SEMAR image (p = 0.011). The variabilities in D90(p = 0.001), V100(p = 0.007), and V150(p = 0.007) were significantly reduced for seed location on the SEMAR image as compared with non-SEMAR image.
  
  
  
  Prostate postimplant CT with SEMAR improved the accuracy of seed localization and postimplant dosimetric parameters.
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan. Electronic address: shiraishi@rad.med.keio.ac.jp.
authors: Yutaka
authors: Y
authors: Shiraishi
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan. Electronic address: yamada@rad.med.keio.ac.jp.
authors: Yoshitake
authors: Y
authors: Yamada
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors: Tomoki
authors: T
authors: Tanaka
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors: Takahisa
authors: T
authors: Eriguchi
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors: Shuichi
authors: S
authors: Nishimura
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors: Kayo
authors: K
authors: Yoshida
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors: Takashi
authors: T
authors: Hanada
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors: Toshio
authors: T
authors: Ohashi
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors: Naoyuki
authors: N
authors: Shigematsu
authors: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors: Masahiro
authors: M
authors: Jinzaki
mesh_terms: D000465:Algorithms; D016477:Artifacts; D001918:Brachytherapy / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008297:Male; D008670:Metals; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D011874:Radiometry / Q000379:methods; D011879:Radiotherapy Dosage; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D007457:Iodine Radioisotopes; D008670:Metals
keywords: Brachytherapy; I-125; Metal artifact reduction; Prostate