Cerebral Hemodynamics and Metabolism in Patients With Symptomatic Occlusion of the Internal Carotid Artery

Abstract

Background and Purpose-The goals of this study were to investigate (1) whether the concentrations of choline, creatine, and N-acetyl aspartate (NAA) in cerebral white matter are changed in patients with symptomatic occlusion of the internal carotid artery (ICA) and (2) whether possible changes in metabolite concentration are related to regional cerebral perfusion or cerebral vasoreactivity. Methods-In 19 patients (meanϮSD age, 60Ϯ9 years), white matter metabolite concentrations were measured with proton MR spectroscopic imaging on average 4Ϯ2 months after symptoms occurred. In selected voxels, corresponding cerebral blood flow and volume, mean transit time, and time-to-bolus peak were determined with dynamic susceptibility contrast MRI. Cerebral CO 2 reactivity was determined with transcranial Doppler sonography. Results-No significant changes in choline and creatine concentrations were observed. NAA concentration was significantly reduced in the hemisphere on the side of the symptomatic ICA (9.1Ϯ1.7 mmol/L) compared with the contralateral hemisphere (10.5Ϯ1.7 mmol/L, PϽ0.005) and control subjects (10.5Ϯ0.9 mmol/L, PϽ0.01). Although no significant interhemispheric difference in NAA concentration was found in patients who presented with retinal ischemia, patients with cerebral ischemia had a significantly lower NAA concentration in the symptomatic hemisphere (9.0Ϯ1.7 mmol/L) compared with the asymptomatic hemisphere (10.

Angioplasty and stenting for the occluded internal carotid artery

“…The cerebral perfusion and the metabolite N-acetylaspartate (NAA) is decreased in the symptomatic patients with ICA occlusion. The reduced metabolite NAA suggests the neurons were lost or functional in the lateral of occluded vessel [19]. It implies that conservative treatment alone may not suitable for the subgroup patients [20].…”

Diabetic Brain Damage in Hypertension

“…After adjusting for other clinical characteristics (age, sex, BMI, and status of smoking and hyperlipidemia), cerebral NAA was independently associated with diabetes (standardized ␤ϭϪ0.466; partial R 2 ϭ0.182; PϽ0.001), but it was not significantly associated with 24 …”

“…Because the NAA concentration in white matter was reported to be significantly reduced in patients with symptomatic ICA, 24 we speculated that an impaired cerebral circulation may contribute to neuronal damage. However, neither baseline cerebral blood flow nor CVR in ICAs and MCAs was significantly correlated with the reduction in cerebral NAA.…”

Current understanding of chronic total occlusion of the internal carotid artery (Review)

“…CTO of the ICA may be characterized solely by impairments in cognitive function, including declines in psychomotor speed, executive function and working memory ( 45 , 46 ). In these patients, chronic neuronal damage may be identified in the cerebral white matter, as indicated by reduced N-acetyl aspartate concentration ( 47 ). These pathological findings affect not only the ipsilateral but also the contralateral hemisphere ( 48 ).…”