title: Metastases of colorectal carcinoma: comparison of soft- and hard-copy helical CT interpretation.
abstract: OBJECTIVE
  To compare soft- and hard-copy computed tomographic (CT) image interpretation with regard to evaluation time and detection rates for hepatic and extrahepatic colorectal metastases in candidates for liver surgery.
  
  
  METHODS
  In 20 patients with a history of colorectal carcinoma, two radiologists independently evaluated CT data sets. Focal hepatic lesions were characterized as benign or malignant by using a five-point scale. In each patient, soft-copy readouts and hard-copy printouts were compared for nonenhanced hepatic, contrast material-enhanced hepatic, and contrast-enhanced extrahepatic data sets. A stopwatch was used to document evaluation time. Ninety-two hepatic metastases and six extrahepatic metastatic recurrences were detected with the standard of reference--surgical, intraoperative ultrasonographic, and histologic findings.
  
  
  RESULTS
  Both observers evaluated the contrast-enhanced hepatic data set significantly faster (P =.026 and.009) by using soft-copy readouts. The contrast-enhanced extrahepatic data set was also evaluated significantly faster (P =.010 and.006) with soft-copy readouts. Detection of hepatic and extrahepatic tumor with soft-copy readouts is not significantly superior to that with hard copies. Detection rates of hepatic metastases for nonenhanced and contrast-enhanced CT for both observers ranged from 50%-80% (46-74 of 92) for soft-copy readouts and 46%-75% (42-69 of 92) for hard copies. Interobserver agreement was highest for contrast-enhanced soft-copy readouts for hepatic metastases.
  
  
  CONCLUSIONS
  Soft-copy readouts of contrast-enhanced CT data sets for the detection of hepatic metastases and extrahepatic metastatic recurrences were evaluated significantly faster than were hard copies, with at least equal sensitivity and with excellent interobserver agreement.
authors.affiliation: Department of Radiology, Leiden University Medical Center, Albinusdreef 2, C3-Q, 2333 ZA Leiden, The Netherlands. m.e.j.pilj@lumc.nl
authors.forename: Milan E J
authors.initials: ME
authors.lastname: Pijl
authors.forename: Martin N J M
authors.initials: MN
authors.lastname: Wasser
authors.forename: Elizabeth C
authors.initials: EC
authors.lastname: Joekes
authors.forename: Cornelis J H
authors.initials: CJ
authors.lastname: van de Velde
authors.forename: Johan L
authors.initials: JL
authors.lastname: Bloem
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000556:secondary*; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012372:ROC Curve; D011873:Radiology Information Systems; D013997:Time Factors; D036542:Tomography, Spiral Computed / Q000379:methods; D014962:X-Ray Film