Aging Effects on Cerebral Blood and Cerebrospinal Fluid Flows

Abstract

Phase-contrast magnetic resonance imaging (PC-MRI) is a noninvasive reliable technique, which enables quantification of cerebrospinal fluid (CSF) and total cerebral blood flows (tCBF). Although it is used to study hydrodynamic cerebral disorders in the elderly group (hydrocephalus), there is no published evaluation of aging effects on both tCBF and CSF flows, and on their mechanical coupling. Nineteen young (mean age 27+/-4 years) and 12 elderly (71+/-9 years) healthy volunteers underwent cerebral MRI using 1.5 T scanner. Phase-contrast magnetic resonance imaging pulse sequence was performed at the aqueductal and cervical levels. Cerebrospinal fluid and blood flow curves were then calculated over the cardiac cycle, to extract the characteristic parameters: mean and peak flows, their latencies, and stroke volumes for CSF (cervical and aqueductal) and vascular flows. Total cerebral blood flow was (P<0.01) decreased significantly in the elderly group when compared with the young subjects with a linear correlation with age observed only in the elderly group (R(2)=0.7; P=0.05). Arteriovenous delay was preserved with aging. The CSF stroke volumes were significantly reduced in the elderly, at both aqueductal (P<0.01) and cervical (P<0.05) levels, whereas aqueduct/cervical proportion (P=0.9) was preserved. This is the first work to study aging effects on both CSF and vascular cerebral flows. Data showed (1) tCBF decrease, (2) proportional aqueductal and cervical CSF pulsations reduction as a result of arterial loss of pulsatility, and (3) preserved intracerebral compliance with aging. These results should be used as reference values, to help understand the pathophysiology of degenerative dementia and cerebral hydrodynamic disorders as hydrocephalus.

Aging blunts hyperventilation-induced hypocapnia and reduction in cerebral blood flow velocity during maximal exercise

“…Importantly, the current data are consistent with others that have reported agerelated differences in MCA V mean (Buijs et al 1998;Ainslie et al 2008), and the progressive decline in CBF from the age of 30 to 70 years has been confirmed repeatedly using a variety of imaging techniques (Kashimada et al 1994(Kashimada et al , 1995Buijs et al 1998;Scheel et al 2000;Beason-Held et al 2007;Stoquart-ElSankari et al 2007). …”

Phase-Contrast MR Imaging Support for the Diagnosis of Aqueductal Stenosis

“…Data were analyzed by using an in-house image-processing software, 11 with an optimized CSF and blood-flow segmentation algorithm, which automatically extracts the region of interest at each level and calculates its flow curves over the 16 segments of the CC (for more details, refer to the description of the processing protocol in previous studies 11,21 ).…”

Arterial hypertension impact on cerebral blood flow in patients with Alzheimer’s disease

“…36 Given that our results, in particular the mean blood flow in the aHT-subjects at the extra-and intracranial levels -were similar to the elderly population studied by Stoquart-El Sankari et al in 2007 34 but different from the aHT+ population, suggests the impact of hypertension on vascular blood flow. A study by Kuyumcu et al showed conflicting results.…”

“…The mean cerebral blood flow in the young and elderly subjects was 688 ± 115 ml/min and 509 ± 103 ml/ min, respectively. 34 In our aHT-population, consisting of 9 patients, the mean cerebral blood flow was 508 ± 94 ml/min at extracranial level and 509 ± 103 ml/ min at intracranial level. The mean age of our aHT-population was 79 ± 5 years old, which is older than the population in the study of Stoquart-El Sankari.…”