title: Clinical evaluation of semi-automatic landmark-based lesion tracking software for CT-scans.
abstract: BACKGROUND
  To evaluate a semi-automatic landmark-based lesion tracking software enabling navigation between RECIST lesions in baseline and follow-up CT-scans.
  
  
  METHODS
  The software automatically detects 44 stable anatomical landmarks in each thoraco/abdominal/pelvic CT-scan, sets up a patient specific coordinate-system and cross-links the coordinate-systems of consecutive CT-scans. Accuracy of the software was evaluated on 96 RECIST lesions (target- and non-target lesions) in baseline and follow-up CT-scans of 32 oncologic patients (64 CT-scans). Patients had to present at least one thoracic, one abdominal and one pelvic RECIST lesion. Three radiologists determined the deviation between lesions' centre and the software's navigation result in consensus.
  
  
  RESULTS
  The initial mean runtime of the system to synchronize baseline and follow-up examinations was 19.4 ± 1.2 seconds, with subsequent navigation to corresponding RECIST lesions facilitating in real-time. Mean vector length of the deviations between lesions' centre and the semi-automatic navigation result was 10.2 ± 5.1 mm without a substantial systematic error in any direction. Mean deviation in the cranio-caudal dimension was 5.4 ± 4.0 mm, in the lateral dimension 5.2 ± 3.9 mm and in the ventro-dorsal dimension 5.3 ± 4.0 mm.
  
  
  CONCLUSIONS
  The investigated software accurately and reliably navigates between lesions in consecutive CT-scans in real-time, potentially accelerating and facilitating cancer staging.
authors.forename: Peter
authors.initials: P
authors.lastname: Dankerl
authors.forename: Alexander
authors.initials: A
authors.lastname: Cavallaro
authors.forename: Matthias
authors.initials: M
authors.lastname: Dietzel
authors.forename: Alexey
authors.initials: A
authors.lastname: Tsymbal
authors.forename: Martin
authors.initials: M
authors.lastname: Kramer
authors.forename: Sascha
authors.initials: S
authors.lastname: Seifert
authors.forename: Michael
authors.initials: M
authors.lastname: Uder
authors.forename: Matthias
authors.initials: M
authors.lastname: Hammon
mesh_terms: D000328:Adult; D000368:Aged; D003936:Diagnosis, Computer-Assisted; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000000981:diagnostic imaging*; D012984:Software; D014057:Tomography, X-Ray Computed