Contralateral stenosis as a risk factor for carotid endarterectomy measured by near infrared spectroscopy
K Yamamoto1, T Komiyama, T Miyata
1Unit of Vascular Surgery, Department of Surgery, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Aim:
It is still controversial whether the existence of a contralateral stenosis is a risk factor during carotid endarterectomy (CEA). We used a near infrared spectroscopy (NIRS) monitoring system during CEA to evaluate the hemodynamic effect of contralateral stenosis during cross clamping of the carotid arteries.
Methods:
We monitored 34 consecutive cases of CEA, using NIRS. Tissue oxygen index (TOI), as a parameter of oxygenation, and total hemoglobin index (THI), as a parameter of blood volume, were measured during cross-clamping the carotid arteries. We evaluated the relationship between these results and the pre- and intraoperative characteristics including the existence of a contralateral stenosis and the results of single-photon emission computed tomography (SPECT).
Results:
Bilateral TOI and THI correlated well with the severity of the stenosis of the contralateral internal carotid artery, and ipsilateral THI correlated with the cerebrovascular reserve measured by SPECT.
Conclusions:
A contralateral stenosis is a risk factor for CEA from the hemodynamical point of view, and extreme care should be taken when performing CEA in patients with bilateral stenoses.
