title: Computed tomography pulmonary angiography in acute pulmonary embolism: the effect of a computer-assisted detection prototype used as a concurrent reader.
abstract: OBJECTIVE
  To assess the effect of computer-assisted detection (CAD) on diagnostic accuracy, reader confidence, and reading time when used as a concurrent reader for the detection of acute pulmonary embolism in computed tomography pulmonary angiography.
  
  
  METHODS
  In this institutional review board-approved retrospective study, 6 observers with varying experience evaluated 158 negative and 38 positive consecutive computed tomography pulmonary angiographies (mean patient age 60 y; 115 women) without and with CAD as a concurrent reader. Readers were asked to determine the presence of pulmonary embolism, assess their diagnostic confidence using a 5-point scale, and document their reading time. Results were compared with an independent standard established by 2 readers, and a third chest radiologist was consulted in case of discordant findings.
  
  
  RESULTS
  Using logistic regression for repeated measurements, we found a significant increase in readers' sensitivity (P<0.001) without loss of specificity (P=0.855) with the effects being reader dependent (P<0.001). Sensitivities varied from 68% to 100% without CAD and from 76% to 100% with CAD. A 2-way analysis of variance showed a small but significant decrease in reading time (P<0.001), with the duration varying between 24 and 208 seconds without CAD and between 17 and 196 seconds with CAD, and a significant increase in readers' confidence scores using CAD as a concurrent reader (P<0.001).
  
  
  CONCLUSIONS
  CAD as a concurrent reader has the potential to increase readers' sensitivity and confidence with a decrease in reading time without loss of specificity. The differences between readers, however, require further evaluation of CAD as a concurrent reader in a larger trial before stronger conclusions can be drawn.
authors.affiliation: Department of Radiology, University Medical Center Utrecht, The Netherlands. rianne_wittenberg@hotmail.com
authors.forename: Rianne
authors.initials: R
authors.lastname: Wittenberg
authors.forename: Joost F
authors.initials: JF
authors.lastname: Peters
authors.forename: Inge A H
authors.initials: IA
authors.lastname: van den Berk
authors.forename: Nicole J M
authors.initials: NJ
authors.lastname: Freling
authors.forename: Rutger
authors.initials: R
authors.lastname: Lely
authors.forename: Bartjan
authors.initials: B
authors.lastname: de Hoop
authors.forename: Karin
authors.initials: K
authors.lastname: Horsthuis
authors.forename: Cécile J
authors.initials: CJ
authors.lastname: Ravesloot
authors.forename: Michael
authors.initials: M
authors.lastname: Weber
authors.forename: W Mathias
authors.initials: WM
authors.lastname: Prokop
authors.forename: Cornelia M
authors.initials: CM
authors.lastname: Schaefer-Prokop
mesh_terms: D000208:Acute Disease; D000792:Angiography; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*