title: Processing and interpretation times of CT angiogram and CT perfusion in stroke.
abstract: OBJECTIVE
  To determine the mean time for acquiring computed tomogram perfusion (CTP) and CT angiogram (CTA) images in acute stroke. To determine and compare processing and interpretation times amongst three groups of radiologists with varying degree of expertise: two radiology residents (Group I), two neuroradiology fellows (Group II) and four consultant neuroradiologists (Group III).
  
  
  METHODS
  The mean time of acquisition of CTA and CTP studies was calculated among ten patients presenting with acute stroke. All readers had to process the CTA and CTP images, interpret them (for presence or absence of thrombus and penumbra) and save them on the GE Advantage Windows workstation. The mean time for processing and interpreting these studies was calculated.
  
  
  RESULTS
  The mean time for acquisition of CTA and CTP studies in the ten patients was 14.6 +/- 5.9 minutes. The time taken for CTA processing and interpretation in Groups I, II and III was 2.3 +/- 1.3 min, 1.6 +/- 0.4 min and 1.5 +/- 0.7 min respectively. The time required for CTP processing and interpretation by the same groups was 5.2 +/- 1.7 min, 4.5 +/- 1.5 min and 4.1 +/- 1.1 min respectively. There was a statistically significant difference of means between Groups I and III in the CTA and CTP processing and interpretation times (p=0.02, p=0.01 respectively) but no statistical difference between Groups I and II (p=0.15, p=0.22 respectively) or Groups II and III (p=0.31, p=0.30 respectively).
  
  
  CONCLUSIONS
  The CTA and CTP studies can be performed, processed and interpreted quickly in acute stroke.
authors.affiliation: Department of Diagnostic Imaging, The Ottawa Hospital, Ottawa, Canada.
authors.forename: Ashok
authors.initials: A
authors.lastname: Srinivasan
authors.forename: Mayank
authors.initials: M
authors.lastname: Goyal
authors.forename: Cheemun
authors.initials: C
authors.lastname: Lum
authors.forename: Thanh
authors.initials: T
authors.lastname: Nguyen
authors.forename: William
authors.initials: W
authors.lastname: Miller
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010477:Perfusion; D011897:Random Allocation; D012189:Retrospective Studies; D020521:Stroke / Q000000981:diagnostic imaging*; D013997:Time Factors; D014057:Tomography, X-Ray Computed