Pre-operative methods to predict need for shunting during carotid endarterectomy

To establish whether pre-operative investigations are able to predict cerebral tolerance to carotid cross clamping during carotid endarterectomy (CEA).

A search of the MEDLINE database from 1950 to 2015 was made in combination with manual cross-referencing using the search strategy: ("carotid" [all fields] AND "endarterectomy" [all fields]) AND "preoperative" [all fields]) AND "clamping" [all fields]) AND ("MRA" [all fields] OR "MRI" [all fields] OR "CT" [all fields] OR "CTA" [all fields] OR "EEG" [all fields] OR "Doppler" [all fields] OR "angiography" [all fields]). A total of 20 studies were identified as eligible for inclusion.

3D Time of Flight MRA and acetazolomide stress SPECT imaging have been reported to have a negative predictive value of 96% and 94% respectively for the need for intraoperative shunting during carotid endarterectomy.

There is some evidence to suggest that pre-operative imaging investigations can reliably identify which patients undergoing CEA will not require carotid shunting for neurological protection. However, this evidence is limited and there is a need for more rigorous studies to be conducted.