title: Automated measurement of lymph nodes: a phantom study.
abstract: The purpose of this study was to assess the accuracy of automated nodal quantification in a phantom. MDCT of a phantom with 17 synthetic lymph nodes of different sizes (diameter 6.0-30.0 mm) was performed at varying tube currents, reconstruction kernels and slice thicknesses. RECIST diameter and volume were measured using an automated software tool. Results were compared with the reference diameter and volume by calculating the absolute percentage error (APE). Degree of agreement between software and reference measurements was evaluated by computing corresponding concordance correlation coefficients (CCC). Under varying tube currents the mean APE (CCC) varied between 5.18% and 10.12% (0.95-0.99) for RECIST diameter and between 7.22% and 16.21% (0.94-1.00) for the volume. At different reconstruction kernels the mean APE values ranged between 7.20% and 7.55% (0.99) (RECIST) and between 8.96% and 14.42% (1.00) (volume). With different slice thicknesses the mean APE values differed from 5.81% to 9.20% (0.97-0.99) (RECIST) and from 8.16% to 22.66% (0.99-1.00) (volume). Regarding RECIST criteria and volume, automated evaluation of lymph nodes in a phantom demonstrated a high accuracy under varying MDCT parameters.
authors.affiliation: Department of Diagnostic Radiology, University Hospital, RWTH Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany. keil@rad.rwth-aachen.de
authors.forename: Sebastian
authors.initials: S
authors.lastname: Keil
authors.forename: Cedric
authors.initials: C
authors.lastname: Plumhans
authors.forename: Florian F
authors.initials: FF
authors.lastname: Behrendt
authors.forename: Sven
authors.initials: S
authors.lastname: Stanzel
authors.forename: Michael
authors.initials: M
authors.lastname: Suehling
authors.forename: Georg
authors.initials: G
authors.lastname: Mühlenbruch
authors.forename: Andreas H
authors.initials: AH
authors.lastname: Mahnken
authors.forename: Rolf W
authors.initials: RW
authors.lastname: Günther
authors.forename: Marco
authors.initials: M
authors.lastname: Das
mesh_terms: D000465:Algorithms; D001331:Automation; D003201:Computers; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008198:Lymph Nodes / Q000000981:diagnostic imaging* / Q000473:pathology*; D009362:Neoplasm Metastasis; D010363:Pattern Recognition, Automated; D019047:Phantoms, Imaging; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012984:Software; D014584:User-Computer Interface