title: Transcranial Doppler ultrasonography in acute ischemic stroke predicts stroke subtype and clinical outcome: a study in Omani population.
abstract: BACKGROUND
  Transcranial Doppler ultrasonography (TCD) is being increasingly used for its ability to provide cerebral hemodynamic information in stroke. Few studies have explored its association with cerebral arteriographic changes and stroke subtype. This study explored the relation of TCD changes in acute stroke with stroke subtypes, MR cerebral arteriography and clinical outcome in Omani population.
  
  
  METHODS
  Adult patients presenting with acute ischemic stroke within 4 days of stroke onset were subjected to TCD through the temporal and suboccipital windows using a 2 MHz probe; flow velocities, pulsatility and direction of flow were recorded from arteries at the skull base. MR arteriographic (MRA) changes on corresponding arteries were graded on a scale of 1-4. ANOVA, student's t test and ROC analysis were used to evaluate TCD in relation to stroke type, outcome and stenosis on MRA.
  
  
  RESULTS
  Of 60 patients recruited, 52 (M:F::36:16; mean age: 60 + 13 years) had adequate bone window for TCD study. Large artery stroke occurred in 30 (58%) patients; lacunar stroke-11 (21%); cardioembolic and mixed groups 9 (17%), other specificed causes-2 (4%). 86.5% had evidence of intracranial disease. 10/52 patients (19%) died while 33 (63%) had good outcome (modified Rankin Score 0-3). Of the 186 arteries studied by the two methods, 52 had TCD evidence of stenosis while 42 were abnormal on MRA, giving a sensitivity of 60%, specificity: 81.25%; positive likelihood ratio: 3.18 and negative likelihood ratio: 0.5. 29/52 (56%) of patients had TCD changes in the arteries corresponding to stroke location. Abnormal TCD was associated with large artery strokes (p = 0.007), poor outcome (p = 0.038) and mortality (p = 0.01).
  
  
  CONCLUSIONS
  This study of TCD in acute stroke in Omani population demonstrates a relatively higher burden of intracranial arterial disease. TCD changes are associated with type of stroke and outcome in this population. TCD is a simple and fairly useful method of evaluation in patients with acute stroke. Adopting TCD in evaluation of stroke patients may provide useful information regarding the pathophysiology which could enhance patient management.
authors.affiliation: Department of Medicine (Neurology), College of Medicine and Health Sciences, Sultan Qaboos University, PO Box 35, PC 123 Muscat, Oman. grarunoday@hotmail.com
authors.forename: Arunodaya R
authors.initials: AR
authors.lastname: Gujjar
authors.forename: Ranjan
authors.initials: R
authors.lastname: William
authors.forename: P C
authors.initials: PC
authors.lastname: Jacob
authors.forename: Rajeev
authors.initials: R
authors.lastname: Jain
authors.forename: Abdullah R
authors.initials: AR
authors.lastname: Al-Asmi
mesh_terms: D000368:Aged; D001037:Aphasia / Q000473:pathology; D050197:Atherosclerosis / Q000473:pathology; D002545:Brain Ischemia / Q000473:pathology; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D008875:Middle Aged; D009850:Oman; D011446:Prospective Studies; D020521:Stroke / Q000175:diagnosis* / Q000503:physiopathology; D016896:Treatment Outcome; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods*