title: Comparison of image quality using a X-ray stereotactical whole-body system and a direct flat-panel X-ray device in examinations of the pelvis and knee.
abstract: OBJECTIVE
  The novel biplanar X-ray unit "EOS", EOS Imaging, allows to acquire simultaneously 2 perpendicular planes of full-length spine and limbs and to measure spatially correct angles based on the acquired image data sets. This is to be seen alongside with a low spatial resolution, high investment costs and high operating expenses. The use of the biplanar X-ray unit in morphology based scelettal radiography might improve the cost-benefit-relation. Thus, the purpose of this study was to compare image quality of the EOS-unit and the flat panel (FP)-technology as reference in a clinical setting.
  
  
  METHODS
  All 114 patients of the Orthopedic Hospital Dept., who had a biplanar full-length lower limb radiograph and a FP-examination of the pelvis and/or the knee with maximum time interval of 3 months without changes in the clinical and radiological findings were included in the study. All X-ray examinations had been carried out due to clinical indications. Secondary captures comparable to the FP-images were extracted from the electronic EOS-image data sets. 4 radiologists independently from each other compared the visualization of normal anatomical structures of the pseudonymous EOS- and FP-images in a randomized order.
  
  
  RESULTS
  In the overwiew of all readers and all sceletal regions image quality of the FP-images was considered being superior in a mean of 83 ± 13 % standard deviation of the pair comparisons (minimum 48 %, maximum 100 %). Image quality of the EOS-images was assessed as being superior in 2 ± 3 % of the cases (0 %, 10 %). Image quality of 0.8 ± 3 % of the FP-images (0 %, 17 %) and 30 ± 34 % (0 %, 100 %) of the EOS-images was estimated as diagnostically inadequate. 30 ± 33 % of the pair comparisons (0 %, 100 %) showed a diagnostically inadequate image quality of the EOS-images and a diagnostically good image quality of the FP-images.
  
  
  CONCLUSIONS
  Image quality of biplanar full-length lower limb X-ray examinations is not suitable to be used for the diagnostic assessment of the morphological bone structure using the currently available technological setting.
  
  
  CONCLUSIONS
  ▶ biplanar full-length lower limb X-ray examinations ▶ plat-panel radiography ▶ image quality.
authors.affiliation: Dept. of Radiology, University of Cologne Medical School, Cologne.
authors.forename: K B
authors.initials: KB
authors.lastname: Krug
authors.affiliation: Dept. of Radiology, University of Cologne Medical School, Cologne.
authors.forename: C
authors.initials: C
authors.lastname: Weber
authors.affiliation: Dept. of Radiology, University of Cologne Medical School, Cologne.
authors.forename: H
authors.initials: H
authors.lastname: Schwabe
authors.affiliation: Dept. of Radiology, University of Cologne Medical School, Cologne.
authors.forename: N-M
authors.initials: NM
authors.lastname: Sinzig
authors.affiliation: Clinic of the Kapuzinerkarree, Aachen.
authors.forename: B
authors.initials: B
authors.lastname: Wein
authors.affiliation: Dept. of Radiology, University of Cologne Medical School, Cologne.
authors.forename: D
authors.initials: D
authors.lastname: Müller
authors.affiliation: Clinic of Orthopedic and Trauma Surgery, University of Cologne Medical School, Cologne.
authors.forename: K
authors.initials: K
authors.lastname: Wegmann
authors.affiliation: Test Center for Radiation Protection GmbH, Wennigsen.
authors.forename: S
authors.initials: S
authors.lastname: Peters
authors.affiliation: Test Center for Radiation Protection GmbH, Wennigsen.
authors.forename: V
authors.initials: V
authors.lastname: Sendler
authors.affiliation: Test Center for Radiation Protection GmbH, Wennigsen.
authors.forename: K
authors.initials: K
authors.lastname: Ewen
authors.affiliation: Dept. of Medical Statistics, Informatics and Epidemiology, University of Cologne Medical Faculty, Cologne.
authors.forename: M
authors.initials: M
authors.lastname: Hellmich
authors.affiliation: Dept. of Radiology, University of Cologne Medical School, Cologne.
authors.forename: D
authors.initials: D
authors.lastname: Maintz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D007717:Knee / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D010388:Pelvis / Q000000981:diagnostic imaging*; D011859:Radiography; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013238:Stereotaxic Techniques / Q000295:instrumentation*; D051598:Whole Body Imaging / Q000295:instrumentation*; D014963:X-Ray Intensifying Screens; D055815:Young Adult