Distribution of cerebral blood flow in the caudate nucleus, lentiform nucleus and thalamus in patients with carotid artery stenosis.

Objective: To investigate the influence of internal carotid artery (ICA) stenosis on the distribution of blood flow to the caudate nucleus, lentiform nucleus, and thalamus.
Methods: We studied 18 healthy control subjects, 20 patients with a unilateral asymptomatic ICA stenosis, and 15 patients with a recently symptomatic unilateral ICA stenosis. The contribution of the ICAs and the basilar artery to the perfusion of the deep brain structures was assessed by perfusion territory selective arterial spin labeling (ASL) MRI. Differences were tested with a two-tailed Fishers' exact test.
Results: The caudate nucleus was predominantly supplied with blood by the ipsilateral ICA in all groups. In 4 of the 15 (27%) the symptomatic patients, the caudate nucleus partially received blood from the contralateral ICA, compared to none of the 18 healthy control subjects (p = 0.03). The lentiform nucleus and the thalamus were predominantly supplied with blood by the ipsilateral ICA and basilar artery respectively in all groups.
Conclusion: In patients with a symptomatic ICA stenosis, the caudate nucleus may be supplied with blood by the contralateral ICA more often than in healthy controls.