title: Selective propofol injection into the M1 segment of the middle cerebral artery (MCA Wada test) reduces adverse effects and enhances the reliability of the Wada test for determining speech dominance.
abstract: OBJECTIVE
  The Wada test is had been the most reliable for determining speech dominance. Drugs injected into the internal carotid artery, however, may be heterogeneously distributed as the result of asymmetry of the anterior cerebral arteries and the presence of a fetal-type posterior cerebral artery. Variations in drug distribution could occasionally alter consciousness and complicate the evaluation of the test results. We examined selective propofol injection into the M1 segment of the middle cerebral artery (MCA Wada test).
  
  
  METHODS
  For the MCA Wada test (17 patients), 7 or 8 mg of propofol was injected via a microcatheter navigated into the M1 segment, and language function was evaluated by patient performing several tasks. The conventional Wada test (internal carotid artery [ICA] Wada test) was performed in four patients (both the ICA and MCA Wada tests were performed in one patient). The efficacy and adverse effects of both procedures were evaluated; all tests were performed by well-trained interventional neuroradiologists.
  
  
  RESULTS
  Immediately after propofol injection during the MCA Wada test, patients developed transient contralateral hemiplegia and transient aphasia (in the case of injection on the dominant side). Confusion and other severe adverse effects did not occur during the MCA Wada test, but two of four patients who underwent the ICA Wada test showed altered consciousness that affected the performance of the test.
  
  
  CONCLUSIONS
  The MCA Wada test is a feasible and reliable preoperative evaluation, if performed by a trained team of interventional neuroradiologists.
authors: Department of Neurosurgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors: Masazumi
authors: M
authors: Fujii
authors: Shigeru
authors: S
authors: Miyachi
authors: Noriaki
authors: N
authors: Matsubara
authors: Takeshi
authors: T
authors: Kinkori
authors: Shigenori
authors: S
authors: Takebayashi
authors: Takashi
authors: T
authors: Izumi
authors: Tomotaka
authors: T
authors: Ohshima
authors: Arihito
authors: A
authors: Tsurumi
authors: Osamu
authors: O
authors: Hososhima
authors: Toshihiko
authors: T
authors: Wakabayashi
authors: Jun
authors: J
authors: Yoshida