Spontaneous slow hemodynamic oscillations are impaired in cerebral microangiopathy

• Published in: Journal of cerebral blood flow and metabolism 2005-12, Vol.25 (12), p.1675-1684
• Main Authors: Schroeter, Matthias L, Bücheler, Markus M, Preul, Christoph, Scheid, Rainer, Schmiedel, Ole, Guthke, Thomas, von Cramon, D Yves
• Format: Article
• Language: English
• Subjects: Aged; Biological and medical sciences; Brain Ischemia - pathology; Brain Ischemia - physiopathology; Cerebral Angiography; Cerebral circulation. Blood-brain barrier. Choroid plexus. Cerebrospinal fluid. Circumventricular organ. Meninges; Cerebrovascular Circulation; Dementia, Vascular - pathology; Dementia, Vascular - physiopathology; Female; Fundamental and applied biological sciences. Psychology; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Humans; Magnetic Resonance Imaging; Male; Medical sciences; Microcirculation; Middle Aged; Nervous system (semeiology, syndromes); Neurology; Neuropsychological Tests; Periodicity; Spectroscopy, Near-Infrared; Vascular diseases and vascular malformations of the nervous system; Vertebrates: nervous system and sense organs
• ISSN: 0271-678X; 1559-7016
• DOI: 10.1038/sj.jcbfm.9600159

Small-vessel disease or cerebral microangiopathy (CMA) is a common finding in elderly people. It is related to a variety of vascular risk factors and may finally lead to subcortical ischemic vascular dementia. Because vessel stiffness is increased, we hypothesized that slow spontaneous oscillations are reduced in cerebral hemodynamics. Accordingly, we examined spontaneous oscillations in the visual cortex of 13 patients suffering from CMA, and compared them with 14 agematched controls. As an imaging method we applied functional near-infrared spectroscopy, because it is particularly sensitive to the microvasculature. Spontaneous low-frequency oscillations (LFOs) (0.07 to 0.12 Hz) were specifically impaired in CMA in contrast to spontaneous very-low-frequency oscillations (0.01 to 0.05 Hz), which remained unaltered. Vascular reagibility was reduced during visual stimulation. Interestingly, changes were tightly related to neuropsychological deficits, namely executive dysfunction. Vascular alterations had to be attributed mainly to the vascular risk factor arterial hypertension. Further, results suggest that the impairments might be, at least partly, reversed by medical treatment such as angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers. Results indicate that functional near-infrared spectroscopy may detect changes in the microvasculature due to CMA, namely an impairment of spontaneous LFOs, and of vascular reagibility. Hence, CMA accelerates microvascular changes due to aging, leading to impairments of autoregulation.