title: Automated "Bone Subtraction" Image Analysis Software Package for Improved and Faster CT Monitoring of Longitudinal Spine Involvement in Patients with Multiple Myeloma.
abstract: The study aimed to assess the diagnostic benefit of a novel computed tomography (CT) post-processing software generating subtraction maps of longitudinal non-enhanced CT examinations for monitoring the course of myeloma bone disease in the spine.
  
  
  
  The local institutional review board approved the retrospective data evaluation. Included were 82 consecutive myeloma patients (46 male; mean age, 65.08 ± 9.76) who underwent 188 repeated whole-body reduced-dose Multislice Detector Computed Tomography (MDCT) at our institution between December 2013 and January 2016. Lytic bone lesions were categorized as new or enlarging versus stable. Bone subtraction maps were read in combination with corresponding 1-mm source images comparing results to those of standard image reading of 5-mm axial and 2-mm multiplanar reformat reconstructions (MPR) scans and hematologic markers, and classified as either progressive disease (PD) or stable disease (SD or remission). The standard of reference was 1-mm axial CT image reading + hematologic response both confirmed at follow-up. For statistical purposes, we subgrouped the hematologic response categories similarly to those applied for CT imaging (progression vs stable/response).
  
  
  
  According to the standard of reference, 16 patients experienced PD and 66 SD at follow-up. Th sensitivity, specificity, and accuracy for axial 5 mm + 2 mm MPR image versus bone subtraction maps in a "lesion-by-lesion" reading were 97.6%, 92.3%, and 97.2% versus 97.8%, 96.7%, and 97.7%, respectively. The use of bone subtraction maps resulted in a change of response classification in 9.7% of the patients (n = 8) versus 5 mm + 2 mm MPR image reading from SD to PD. Bone sclerosis lesions were detected in 52 out of 82 patients (63.4%). The reading time was significantly lower with the software bone subtraction compared to standard reading (P < 0.01) and 1-mm image reading (P < 0.001).
  
  
  
  Accuracy of bone subtraction maps reading for monitoring multiple myeloma is slightly increased over that of conventional axial + MPR image reading and significantly speeds up the reading time.
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany.
authors.forename: Marius
authors.initials: M
authors.lastname: Horger
authors.affiliation: Sector Imaging and Interventional Radiology, Siemens AG Healthcare, Forchheim, Germany.
authors.forename: Hendrick
authors.initials: H
authors.lastname: Ditt
authors.affiliation: Siemens Medical Solutions, Malvern, Pennsylvania.
authors.forename: Shu
authors.initials: S
authors.lastname: Liao
authors.affiliation: Department of Internal Medicine II, Eberhard-Karls-University Tübingen, Tübingen, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Weisel
authors.affiliation: Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Jan
authors.initials: J
authors.lastname: Fritz
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany.
authors.forename: Wolfgang M
authors.initials: WM
authors.lastname: Thaiss
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Kaufmann
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Nikolaou
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany. Electronic address: christopher.kloth@med.uni-tuebingen.de.
authors.forename: Christopher
authors.initials: C
authors.lastname: Kloth
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D009101:Multiple Myeloma / Q000175:diagnosis*; D009367:Neoplasm Staging; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012984:Software; D013125:Spinal Neoplasms / Q000175:diagnosis*; D013382:Subtraction Technique; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging*; D051598:Whole Body Imaging / Q000379:methods
keywords: CT imaging; Multiple myeloma; bone subtraction maps; lytic bone lesions; pelvic bones