Diagnostic impact of transcranial color-coded real-time sonography with echo contrast agents for hyperperfusion syndrome after carotid endarterectomy.
OBJECTIVE
The purpose of the present study was to evaluate availability of transcranial color-coded real-time sonography (TCCS) to detect hyperperfusion after carotid endarterectomy (CEA).


METHODS
This prospective study included 105 consecutive patients who underwent CEA for severe carotid stenosis. TCCS with echo contrast agents was performed serially to evaluate flow velocity of the middle cerebral artery (MCA). Regional cerebral blood flow (rCBF) and vasodilatory capacity of the MCA territory were evaluated using single-photon emission computed tomography. We compared the changes in MCA flow velocity with rCBF.


RESULTS
Using echo contrast agents, we could evaluate the MCA flow in 95 (90%) of 105 patients. Twelve patients showed hyperperfusion syndrome. Changes in the MCA mean flow velocity (MFV) before and 4 days after CEA were significantly correlated with those in rCBF (r=0.48; P<0.0001). An increase of >50% in MCA MFV was observed within 4 days after CEA in all 12 patients with hyperperfusion syndrome. Multivariate analysis revealed that reduced vasodilatory capacity (odds ratio, 0.14; 95% CI, 0.04 to 0.46) was an independent risk factor for a 1.5-fold increase in the MFV of MCA ipsilateral to CEA.


CONCLUSIONS
Findings of a 1.5-fold increase in the MCA MFV can accurately identify those patients with high risk of developing post-CEA hyperperfusion syndrome. TCCS with echo contrast agents is available for the evaluation of hyperperfusion after CEA.
Fujimoto
Shigeru
S
Department of Cerebrovascular Disease, Cerebrovascular Center and Clinical Research Institute, National Kyushu Medical Center, Fukuoka, Japan. fujimoto@qmed.hosp.go.jp
Toyoda
Kazunori
K
Inoue
Tooru
T
Hirai
Yuko
Y
Uwatoko
Takeshi
T
Kishikawa
Kazuhiro
K
Yasumori
Kotaro
K
Ibayashi
Setsuro
S
Iida
Mitsuo
M
Okada
Yasushi
Y
D000368:Aged; D001783:Blood Flow Velocity; D002560:Cerebrovascular Circulation; D003287:Contrast Media; D016894:Endarterectomy, Carotid / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery; D012039:Regional Blood Flow; D015427:Reperfusion Injury / Q000175:diagnosis* / Q000209:etiology*; D015899:Tomography, Emission-Computed, Single-Photon; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods
D003287:Contrast Media