Correlation between resting state fMRI total neuronal activity and PET metabolism in healthy controls and patients with disorders of consciousness.
The mildly invasive 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging technique to measure 'resting state' cerebral metabolism. This technique made it possible to assess changes in metabolic activity in clinical applications, such as the study of severe brain injury and disorders of consciousness.



We assessed the possibility of creating functional MRI activity maps, which could estimate the relative levels of activity in FDG-PET cerebral metabolic maps. If no metabolic absolute measures can be extracted, our approach may still be of clinical use in centers without access to FDG-PET. It also overcomes the problem of recognizing individual networks of independent component selection in functional magnetic resonance imaging (fMRI) resting state analysis.



We extracted resting state fMRI functional connectivity maps using independent component analysis and combined only components of neuronal origin. To assess neuronality of components a classification based on support vector machine (SVM) was used. We compared the generated maps with the FDG-PET maps in 16 healthy controls, 11 vegetative state/unresponsive wakefulness syndrome patients and four locked-in patients.



The results show a significant similarity with ρ = 0.75 ± 0.05 for healthy controls and ρ = 0.58 ± 0.09 for vegetative state/unresponsive wakefulness syndrome patients between the FDG-PET and the fMRI based maps. FDG-PET, fMRI neuronal maps, and the conjunction analysis show decreases in frontoparietal and medial regions in vegetative patients with respect to controls. Subsequent analysis in locked-in syndrome patients produced also consistent maps with healthy controls.



The constructed resting state fMRI functional connectivity map points toward the possibility for fMRI resting state to estimate relative levels of activity in a metabolic map.
Department of Physics & Astronomy, Brain and Mind Institute Western University London Ontario Canada.
Andrea
A
Soddu
Department of Computer Science Universidad Central de Colombia Bogotá Colombia.
Francisco
F
Gómez
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Lizette
L
Heine
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Carol
C
Di Perri
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Mohamed Ali
MA
Bahri
Department of Radiology Weill Cornell Medical College New York New York.
Henning U
HU
Voss
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Marie-Aurélie
MA
Bruno
Department of Algology and Palliative Care University Hospital of Liège Liège Belgium.
Audrey
A
Vanhaudenhuyse
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Christophe
C
Phillips
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium; Brain and Spine InstituteInstitut du Cerveau et de la Moelle épinière (ICM) Hôpital Pitié-Salpêtrière Paris France.
Athena
A
Demertzi
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Camille
C
Chatelle
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Jessica
J
Schrouff
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Aurore
A
Thibaut
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Vanessa
V
Charland-Verville
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium; Brain Innovation B.V. Maastricht the Netherlands.
Quentin
Q
Noirhomme
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium.
Eric
E
Salmon
Department of Neurology University Hospital of Liège Liège Belgium.
Jean-Flory Luaba
JF
Tshibanda
Department of Radiology Weill Cornell Medical College New York New York.
Nicholas D
ND
Schiff
GIGA-Research & Cyclotron Research Centre University of Liège Liège Belgium; Department of Neurology University Hospital of Liège Liège Belgium.
Steven
S
Laureys
D000328:Adult; D001921:Brain / Q000378:metabolism* / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods; D003244:Consciousness Disorders / Q000378:metabolism* / Q000503:physiopathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D012146:Rest
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
Disorders of consciousness; FDG‐PET; ICA; fMRI; metabolism; resting state