Predictors of poor cerebral collaterals and cerebrovascular reserve in patients with chronic total carotid occlusion.

Background: This study aims to investigate the relationship between cerebrovascular reserve (CVR) capacity, as measured by single-photon emission computed tomography (SPECT) and collateral blood flow, according to a transcranial colour-coded duplex(TCCD), in patients with symptomatic total carotid occlusion (TCO). Additionally, the study aims to determine whether vascular risk factors have an effect on collateral blood flow, as well as on the CVR.

Methods: Thirty-four patients with chronic TCO, diagnosed by carotid duplex scanning and confirmed by other vascular imaging modalities, who had ischaemic symptoms either as stroke or transient ischaemic attack, were subjected to clinical assessment, SPECT under dipyridamole stress, and grading of cerebral collateral blood flow using TCCD.