Hungarian Radiology

[Transcranial Doppler monitoring of distal embolism during of carotid stenting]


MARCH 20, 2007

Hungarian Radiology - 2007;81(01-02)

[INTRODUCTION - Reducing the risk of embolisation during endovascular treatment of internal carotid artery stenosis is very important. The rate of embolisation is affected by the different steps of stenting manipulation. Using transcranial Doppler equipment we studied the embolic signals during the different phases of carotid dilatation and stenting. MATERIAL AND METHOD - 50 patients (33 male, 17 female; mean age 64 years) were intraproceduraly monitorized with transcranial Doppler. Predilatation was necessary in nine cases, postdilatation was performed in 39 cases. The number of emboli were measured in seven different steps of endovascular treatment of carotid stenosis. Different type of commercial available endovascular devices were used. RESULTS - Intraprocedural embolisation was observed in every case. In different phases of carotid stenting the rate of embolisation showed marked differences in each phase of carotid stenting. Crossing the stenosis with stent delivery system were accompanied by a low rate of embolism (5.3) compared to the level during stent opening (9.16) and balloon dilatation (9.96). The highest level of embolisation was observed during predilatation (15.9) without the protection of the stent. CONCLUSIONS - We detected embolisation in all of the cases, however the number of embolic signals varied in different phases of carotid artery stenting. Embolisation can be reduced if the most dangerous steps (i.e. pre- and postdilatation) are avoided. Using TCD monitorisation the physician can be informed by the degree of embolisation that may alarm the interventionalist to perform the procedure more carefully, furthermore it can be employed during the training of carotid stenting.]



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