title: Vertebral artery Doppler waveform patterns for exclusive diagnosis of basilar artery stenosis and occlusion.
abstract: OBJECTIVE
  The aim of this study was to evaluate the usefulness of vertebral artery (VA) pulsed Doppler waveform changes in excluding basilar artery (BA) stenosis/occlusion.
  
  
  METHODS
  One-hundred and twenty-two patients with time-averaged peak flow velocity (MV) of bilateral VAs <18 cm/s, measured by carotid ultrasonography, were included. The pulsatility index (PI) and resistive index (RI) of both VAs were measured. The maximum PI (Max PI) and maximum RI (Max RI) were used for analysis, respectively. BA stenosis/occlusion and fetal-type posterior cerebral artery (f-PCA) were evaluated using MR angiography.
  
  
  RESULTS
  Thirty-six patients had BA stenosis/occlusion. Acute infratentorial cerebral infarction (CI), f-PCA, Max PI, and Max RI were significantly higher in patients with BA stenosis/occlusion. Multiple logistic regression analysis revealed that "Max PI ≥2.00 or Max RI ≥0.82" had an odds ratio of 3.75 (95% CI 1.43-9.84) for diagnosing BA stenosis/occlusion, but the positive predictive value (PPV) was low (42.2%) and negative predictive value (NPV) was high (84.5%). Similarly, "Max PI ≥2.00 and Max RI ≥0.82" had an odds ratio of 2.96 (95% CI 1.18-7.39); PPV was low (44.9%) and NPV was high (80.8%).
  
  
  CONCLUSIONS
  Among the subjects with bilateral VA-MV <18 cm/s, PI and RI could contribute to excluding BA stenosis/occlusion.
authors.affiliation: Stroke Division, Department of Neurology, Dokkyo Medical University, 880 Kitakobayashi, Mibu, Shimotsuga, Tochigi, 321-0293, Japan.
authors.forename: Madoka
authors.initials: M
authors.lastname: Okamura
authors.affiliation: Stroke Division, Department of Neurology, Dokkyo Medical University, 880 Kitakobayashi, Mibu, Shimotsuga, Tochigi, 321-0293, Japan. htakekawa-jscn@umin.ac.jp.|Center of Medical Ultrasonics, Dokkyo Medical University Hospital, Tochigi, Japan. htakekawa-jscn@umin.ac.jp.
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Takekawa
authors.affiliation: Stroke Division, Department of Neurology, Dokkyo Medical University, 880 Kitakobayashi, Mibu, Shimotsuga, Tochigi, 321-0293, Japan.
authors.forename: Ryuta
authors.initials: R
authors.lastname: Okabe
authors.affiliation: Department of Neurology, Dokkyo Medical University, Tochigi, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Suzuki
authors.affiliation: Department of Neurology, Dokkyo Medical University, Tochigi, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Hirata
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002544:Cerebral Infarction / Q000150:complications / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D016015:Logistic Models; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography; D014711:Vertebral Artery / Q000000981:diagnostic imaging*; D014715:Vertebrobasilar Insufficiency / Q000150:complications / Q000175:diagnosis / Q000000981:diagnostic imaging*
keywords: Basilar artery stenosis; Pulsatility index; Resistive index; Vertebral artery