BOLD signal responses to controlled hypercapnia in human spinal cord.
Neuroimage
; 50(3): 1074-84, 2010 Apr 15.
Article
em En
| MEDLINE
| ID: mdl-20060914
ABSTRACT
Functional MRI of the spinal cord is challenging due to the small cross section of the cord and high level of physiological noise. Though blood oxygenation level-dependent (BOLD) contrast has been used to study specific responses of the spinal cord to various stimuli, it has not been demonstrated using a controlled stimulus. In this paper, we use hypercapnic manipulation to study the sensitivity and specificity of functional MRI in the human cervical spinal cord. Simultaneous MR imaging in the brain and spinal cord was performed for direct comparison with the brain, in which responses to hypercapnia have been more extensively characterized. Original contributions include (i) prospectively controlled hypercapnic changes in end-tidal PCO(2), (ii) simultaneous recording of BOLD responses in the brain and spinal cord, and (iii) generation of statistical maps of BOLD responses throughout the brain and spinal cord, taking into account physiological noise sources. Results showed significant responses in all subjects both in the brain and the spinal cord. In anatomically-defined regions of interest, mean percent changes were 0.6% in the spinal cord and 1% in the brain. Analysis of residual variance demonstrated significantly larger contribution of physiological noise in the spinal cord (P<0.005). To obtain more reliable results from fMRI in the spinal cord, it will be necessary to improve sensitivity through the use of highly parallelized coil arrays and better modeling of physiological noise. Finely, we believe that the use of controlled global stimuli, such as hypercapnia, will help assess the effectiveness of new acquisition techniques.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Medula Espinal
/
Hipercapnia
Tipo de estudo:
Prognostic_studies
Limite:
Adult
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
Neuroimage
Assunto da revista:
DIAGNOSTICO POR IMAGEM
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Canadá