TY - JOUR T1 - Blood Flow Changes Caused by Distal Filter Protection and Catheter Aspiration in the Internal Carotid Artery during Carotid Stenting: Evaluation Using Carotid Doppler Sonography JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 288 LP - 293 DO - 10.3174/ajnr.A2276 VL - 32 IS - 2 AU - T. Sorimachi AU - K. Nishino AU - K. Morita AU - S. Takeuchi AU - Y. Ito AU - Y. Fujii Y1 - 2011/02/01 UR - http://www.ajnr.org/content/32/2/288.abstract N2 - BACKGROUND AND PURPOSE: If blood flow in the ICA is reduced by the use of a distal filter during CAS, flow stagnation proximal to the filter occurs and this increases the probability of floating debris. The floating debris that remains after filter retrieval may cause cerebral embolism. However, if blood flow is increased by aspiration of blood from the ICA through an aspiration catheter, debris could be removed while the filter is still in place. The purpose of this study was to investigate blood flow changes in the ICA induced by filter use and aspiration. MATERIAL AND METHODS: A filter-protection device (AngioGuard XP) was used during CAS in 13 consecutive patients with carotid stenosis. Blood flow velocity in the ICA was measured by carotid Doppler sonography during filter deployment, filter retrieval, and catheter aspiration. RESULTS: Blood flow velocity significantly decreased with filter placement and significantly increased with filter retrieval in patients with normal angiographic flow (P < .05). Aspiration of a 20-mL blood sample from the proximal ICA column significantly increased the blood flow velocity (P < .05). CONCLUSIONS: The blood flow changes in the ICA induced by the use of a distal filter may cause cerebral embolism in filter-protected CAS. A routine aspiration method can potentially reduce the amount of migrating debris during CAS, even in cases with angiographic normal flow. AGAngioGuardANOVAanalysis of varianceCAScarotid artery stentingDSAdigital subtraction angiographyEDVend-diastolic velocityICAinternal carotid arteryNASCETNorth American Symptomatic Carotid Endarterectomy TrialPostafterPrebeforePSVpeak systolic velocityTAMVtime-averaged maximum velocity ER -