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

- Pre-operative imaging can reliably identify which patients undergoing CEA will not require intra-operative shunting.
- MRA and acetazolomide stress SPECT imaging have shown to be the most promising imaging modalities.
- However, the available evidence is limited and there is a need for more rigorous studies to be conducted.

ObjectivesTo establish whether pre-operative investigations are able to predict cerebral tolerance to carotid cross clamping during carotid endarterectomy (CEA).MethodsA 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.Results3D 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.ConclusionsThere 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.