title: Superficial temporal artery duplex ultrasonography for improved cerebral hemodynamics after extracranial-intracranial bypass surgery.
abstract: BACKGROUND
  To investigate the utility of superficial temporal artery (STA) duplex ultrasonography (STDU) for evaluating the improvement of the cerebral hemodynamics after extracranial-intracranial (EC-IC) bypass.
  
  
  METHODS
  This study included 40 consecutive patients who underwent EC-IC bypass for occlusive disease of cerebral arteries. STDU was performed to measure the flow velocity, pulsatility index, and diameter of the operated STA before and 14 days after EC-IC bypass. Regional cerebral blood flow (rCBF) and acetazolamide (ACZ) reactivity of the ipsilateral middle cerebral artery (MCA) territory were evaluated by quantitative single-photon emission computed tomography with the ACZ challenge test. We investigated the correlation between STA flow velocity/diameter and rCBF/ACZ reactivity in the ipsilateral MCA territory.
  
  
  RESULTS
  Mean flow velocity (MFV; 26.3 +/- 8.8 to 55.3 +/- 16.3 cm/s, p < 0.0001) and diameter (1.57 +/- 0.24 to 2.26 +/- 0.29 mm, p < 0.0001) of the STA, and rCBF (29.1 +/- 3.1 to 35.0 +/- 6.4 ml/100 g/min, p < 0.0001) and ACZ reactivity (-0.02 +/- 0.10 to 0.28 +/- 0.21, p < 0.0001) of the MCA territory increased after EC-IC bypass compared with the baseline values. STA MFV was significantly correlated with the rCBF 14 days after EC-IC bypass (R = 0.70, p < 0.0001). A cutoff value of postsurgical STA MFV greater than 48.5 cm/s yielded the highest diagnostic accuracy (sensitivity 86%; specificity, 82%) for rCBF > or = 32 ml/100 g/min after EC-IC bypass.
  
  
  CONCLUSIONS
  STDU was available for evaluating postsurgical patency of the bypass flow and the rCBF of the ipsilateral MCA territory. The mean blood flow velocity of the operated STA is a highly sensitive parameter for predicting rCBF in the ipsilateral MCA territory after EC-IC bypass.
authors.affiliation: Department of Cerebrovascular Disease, Cerebrovascular Center and Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Hirai
authors.forename: Shigeru
authors.initials: S
authors.lastname: Fujimoto
authors.forename: Kazunori
authors.initials: K
authors.lastname: Toyoda
authors.forename: Tooru
authors.initials: T
authors.lastname: Inoue
authors.forename: Takeshi
authors.initials: T
authors.lastname: Uwatoko
authors.forename: Noriko
authors.initials: N
authors.lastname: Makihara
authors.forename: Kotaro
authors.initials: K
authors.lastname: Yasumori
authors.forename: Setsuro
authors.initials: S
authors.lastname: Ibayashi
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Iida
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Okada
mesh_terms: D000368:Aged; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation / Q000502:physiology*; D002561:Cerebrovascular Disorders / Q000000981:diagnostic imaging* / Q000601:surgery*; D003251:Constriction, Pathologic; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging; D019635:Neurosurgical Procedures; D011446:Prospective Studies; D013699:Temporal Arteries / Q000000981:diagnostic imaging* / Q000601:surgery*; D015899:Tomography, Emission-Computed, Single-Photon; D018616:Ultrasonography, Doppler, Duplex