title: Validation of transcranial Doppler with magnetic resonance angiography in acute cerebral ischemia.
abstract: OBJECTIVE
  Transcranial Doppler (TCD) is often used as a screening tool for detecting intracranial stenosis. Since TCD results may vary among laboratories and sonographers, it requires validation against an imaging modality. We evaluated diagnostic accuracy of TCD performed in our laboratory against time-of-flight (TOF) magnetic resonance angiography (MRA) in detecting intracranial stenosis in patients with acute cerebral ischemia.
  
  
  METHODS
  Consecutive patients with acute (<24 hours) cerebral ischemia and intracranial arterial stenosis on MRA underwent both TCD and MRA within 5 hours of each other. TCD was performed by credentialed neurosonologists according to standardized protocol. An independent neuroradiologist interpreting MRA was blinded to TCD findings. We evaluated TCD peak systolic velocities (PSV) in proximal intracranial arteries as predictive of moderate (>50%) and severe (>70%) stenosis on TOF-MRA.
  
  
  RESULTS
  One hundred and fifty patients (74% males; mean age 53 years) underwent neurovascular evaluation with TCD and MRA. Twenty-two (14.6%) patients were excluded due to absent temporal acoustic windows. Middle cerebral artery TCD PSV values of >140 cm/s and >180 cm/s were found to predict a >50% and >70% focal stenosis, respectively. Optimal cut-off PSV values for other major proximal intracranial arteries were also established.
  
  
  CONCLUSIONS
  TCD performed in our laboratory shows satisfactory agreement with TOF-MRA in diagnosis and grading of proximal intracranial stenosis in patients with acute cerebral ischemia.
authors.affiliation: Department of Neurology, Nizam's Institute of Medical Sciences, Hyderabad, India.
authors.forename: Demudu Babu
authors.initials: DB
authors.lastname: Boddu
authors.forename: Vijay K
authors.initials: VK
authors.lastname: Sharma
authors.forename: V C S S
authors.initials: VC
authors.lastname: Bandaru
authors.forename: Y
authors.initials: Y
authors.lastname: Jyotsna
authors.forename: D
authors.initials: D
authors.lastname: Padmaja
authors.forename: Alladi
authors.initials: A
authors.lastname: Suvarna
authors.forename: Subhash
authors.initials: S
authors.lastname: Kaul
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D002537:Intracranial Arteriosclerosis / Q000000981:diagnostic imaging* / Q000473:pathology; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000473:pathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods*