Diffusion-weighted imaging to compare different cerebral protection devices in carotid artery stenting.

Aims: Carotid artery stenting (CAS) is commonly performed with cerebral protection devices. New hyperintense lesions on diffusion-weighted MR imaging (DWI) were used to compare different cerebral protection devices.

Methods And Results: Patients (n=33) with high-grade symptomatic carotid stenosis were treated with CAS. Two different methods of cerebral embolic protection were used. In 23 patients, a filter device was placed in the distal internal carotid artery. In 10 patients a protection system based on the reversed-flow principle was used. DWI was performed before and after CAS. The number and volume of new hyperintense lesions in the ipsilateral hemisphere were assessed.No stroke or death was recorded. Twenty-three new hyperintense lesions in the ipsilateral cerebral hemisphere were recorded on the post-treatment DWI-series after stent placement in 12 of the 33 procedures (36%). In 8 of the 23 procedures (35%) performed with a filter device and in 4 of the 10 procedures (40%) performed with the reversed-flow device new hyperintense lesions were revealed (13 and 10, respectively). No significant differences were found in the number of lesions and lesion load. The volume per lesion was significantly smaller in the patient group treated with reversed-flow device in comparison to the patient group treated with a filter device (median 0,048 mm3 and 0,013 mm3, respectively; p=0.03).

Conclusion: This non-randomised study revealed no difference in new subclinical ischaemic lesions in the ipsilateral hemisphere between procedures performed with filter devices and procedures performed with embolic protection using the reversed-flow principle.