title: Evaluation of bone scan index change over time on automated calculation in bone scintigraphy.
abstract: OBJECTIVE
  Bone scintigraphy (bone scan) is useful in detecting metastatic bone lesions through visual assessment of hot spots. A semi-quantitative analysis method that evaluates bone scan images has been eagerly anticipated. BONENAVI is software that enables automatic assessment of bone scan index (BSI). BSI is useful for stratifying cancer patients and monitoring their therapeutic response. The purpose of this study was to evaluate the BONENAVI reading in determining BSI and hot spots at different time intervals after radioisotope injection.
  
  
  METHODS
  We evaluated 32 patients, including 22 males and 10 females. Ten patients had breast cancer, 20 patients had prostate cancer, and 2 had malignant pheochromocytoma. Patients were injected with 740 MBq of (99m)Tc-methylene diphosphonate and bone scintigraphy was performed at 2, 4, and 6 h after injection on each patient. The BSI and the number of hot spots were obtained from BONENAVI software. Bone scan images were also visually assessed to exclude false positives due to artifacts. Analyses were performed in all lesions, selected true lesions, segment based and cancer type based. Non-parametric statistical analyses for pairwise multiple group comparison were performed using Friedman test followed with post hoc analysis.
  
  
  RESULTS
  The BSIs and the number of hot spots were significantly increased with time, with significant differences between each of time points (P < 0.001). Analysis of regional BSI (rBSI) and hot spot number changes of selected 15 true lesions also showed similar increase (P < 0.001). In general, the pelvic segment was the most prone to rBSI changes and the chest segment was the most prone to hot spot number changes. Visual assessment showed that BONENAVI diagnosed some typical artifacts as metastases (hot spots).
  
  
  CONCLUSIONS
  BONENAVI reading of BSIs and hot spot numbers was highly affected by acquisition time. In serial or follow-up examinations (in particular, for monitoring therapeutic efficacy), acquisition time should be fixed for each patient. Cautious interpretation should be made on segments with high physiological uptake. BONENAVI reading was prone to misinterpretation of artifacts. Visual assessment is necessary to rule out this possibility.
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Showa-machi 3-39-22, Maebashi, Gunma, 371-8511, Japan.|Dr. Hasan Sadikin Central General Hospital, Jl. Dr. Pasteur No. 38, Bandung, 40161, Indonesia.
authors.forename: Rini
authors.initials: R
authors.lastname: Shintawati
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Showa-machi 3-39-22, Maebashi, Gunma, 371-8511, Japan.
authors.forename: Arifudin
authors.initials: A
authors.lastname: Achmad
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Showa-machi 3-39-22, Maebashi, Gunma, 371-8511, Japan. tetsuyah92md@gmail.com.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Higuchi
authors.affiliation: Department of Radiology, Gunma University Hospital, Showa-machi 3-39-15, Maebashi, Gunma, 371-8511, Japan.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Shimada
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Showa-machi 3-39-22, Maebashi, Gunma, 371-8511, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Hirasawa
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Showa-machi 3-39-22, Maebashi, Gunma, 371-8511, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Arisaka
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Showa-machi 3-39-22, Maebashi, Gunma, 371-8511, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Takahashi
authors.affiliation: Department of Molecular Imaging, Gunma University Graduate School of Medicine, Showa-machi 3-39-22, Maebashi, Gunma, 371-8511, Japan.
authors.forename: Takahito
authors.initials: T
authors.lastname: Nakajima
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Showa-machi 3-39-22, Maebashi, Gunma, 371-8511, Japan.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Tsushima
mesh_terms: D000368:Aged; D001331:Automation; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D013997:Time Factors
keywords: BONENAVI; Bone scan index; Bone scintigraphy; Computer-assisted diagnostic software