Study of cerebral vasoreactivity with transcranial Doppler and functional MRI in patients with carotid stenosis

• Grant number: 10/52027-1
• Support Opportunities: Regular Research Grants
• Start date: December 01, 2010
• End date: November 30, 2012
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Cynthia Resende Campos Herrera
• Grantee: Cynthia Resende Campos Herrera
• Host Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Ischemic stroke is the leading cause of death and non-traumatic functional disability in Brazil. Therefore, investment in the development of scientific researches about such disease in our country is needed. Carotid atherosclerosis is an important cause of ischemic stroke. The existence of critical atherosclerotic stenosis in the carotid artery increases the risk for stroke, especially when the cerebral vasoreactivity (CV) is impaired. CV may be evaluated through the induction of transient hypercapnia by CO2 inhalation, acetazolamide infusion or by the apnea test while doing specific tests such as the Positron Emission Tomography (PET), which is considered the gold standard. However, due to the practical limitations for using PET, other technologies have been more frequently used, particularly the Transcranial Doppler (TCD). Blood-Oxygen-Level-Dependent Functional Resonance Magnetic Imaging (BOLD-fMRI) can also be used to evaluate the CV. It gives information on the hemodynamic status either on the proximal arterial segments (which are studied on TCD) as on the distal microvasculature, and, additionally, it brings to the study of CV an excellent spatial and anatomical resolution, which is impossible to obtain by doing TCD only. As no studies are available yet on the comparison between TCH and BOLD-fMRI for CV evaluation, we come up with this project. If a good correlation between both methods can be detected, the use of BOLD-fMRI in the process of risk stratification for stroke in patients with carotid atherosclerotic disease might offer the advantage of spatial and temporal resolution and become especially useful when technical issues like absence of acoustic window make TCD inadequate. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

C.R. HERRERA CAMPOS; G.C. BELTRAMINI; W.M. AVELAR; F.O. LIMA; L.M. LI. Cerebral vasomotor reactivity assessment using Transcranial Doppler and MRI with apnea test. Brazilian Journal of Medical and Biological Research, v. 49, n. 11, 2016-10-24. (10/52027-1, 13/07559-3)