TY - JOUR
T1 - Multimodal study of default-mode network integrity in disorders of consciousness
AU - Rosazza, Cristina
AU - Andronache, Adrian
AU - Sattin, Davide
AU - Bruzzone, Maria Grazia
AU - Marotta, Giorgio
AU - Nigri, Anna
AU - Ferraro, Stefania
AU - Rossi Sebastiano, Davide
AU - Porcu, Luca
AU - Bersano, Anna
AU - Benti, Riccardo
AU - Leonardi, Matilde
AU - D'Incerti, Ludovico Ernesto Marsilio
AU - Minati, Ludovico
PY - 2016
Y1 - 2016
N2 - Objective: Understanding residual brain function in disorders of consciousness poses extraordinary challenges, and imaging examinations are needed to complement clinical assessment. The default-mode network (DMN) is known to be dysfunctional, although correlation with level of consciousness remains controversial. We investigated DMN activity with resting-state functional magnetic resonance imaging (rs-fMRI), alongside its structural and metabolic integrity, aiming to elucidate the corresponding associations with clinical assessment. Methods: We enrolled 119 consecutive patients: 72 in a vegetative state/unresponsive wakefulness state (VS/UWS), 36 in a minimally conscious state (MCS), and 11 with severe disability. All underwent structural MRI and rs-fMRI, and a subset also underwent 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). Data were analyzed with manual and automatic approaches, in relation to diagnosis and clinical score. Results: Excluding the quartile with largest head movement, DMN activity was decreased in VS/UWS compared to MCS, and correlated with clinical score. Independent-component and seed-based analyses provided similar results, although the latter and their combination were most informative. Structural MRI and FDG-PET were less sensitive to head movement and had better diagnostic accuracy than rs-fMRI only when all cases were included. rs-fMRI indicated relatively preserved DMN activity in a small subset of VS/UWS patients, 2 of whom evolved to MCS. The integrity of the left hemisphere appears to be predictive of a better clinical status. Interpretation: rs-fMRI of the DMN is sensitive to clinical severity. The effect is consistent across data analysis approaches, but heavily dependent on head movement. rs-fMRI could be informative in detecting residual DMN activity for those patients who remain relatively still during scanning and whose diagnosis is uncertain.
AB - Objective: Understanding residual brain function in disorders of consciousness poses extraordinary challenges, and imaging examinations are needed to complement clinical assessment. The default-mode network (DMN) is known to be dysfunctional, although correlation with level of consciousness remains controversial. We investigated DMN activity with resting-state functional magnetic resonance imaging (rs-fMRI), alongside its structural and metabolic integrity, aiming to elucidate the corresponding associations with clinical assessment. Methods: We enrolled 119 consecutive patients: 72 in a vegetative state/unresponsive wakefulness state (VS/UWS), 36 in a minimally conscious state (MCS), and 11 with severe disability. All underwent structural MRI and rs-fMRI, and a subset also underwent 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). Data were analyzed with manual and automatic approaches, in relation to diagnosis and clinical score. Results: Excluding the quartile with largest head movement, DMN activity was decreased in VS/UWS compared to MCS, and correlated with clinical score. Independent-component and seed-based analyses provided similar results, although the latter and their combination were most informative. Structural MRI and FDG-PET were less sensitive to head movement and had better diagnostic accuracy than rs-fMRI only when all cases were included. rs-fMRI indicated relatively preserved DMN activity in a small subset of VS/UWS patients, 2 of whom evolved to MCS. The integrity of the left hemisphere appears to be predictive of a better clinical status. Interpretation: rs-fMRI of the DMN is sensitive to clinical severity. The effect is consistent across data analysis approaches, but heavily dependent on head movement. rs-fMRI could be informative in detecting residual DMN activity for those patients who remain relatively still during scanning and whose diagnosis is uncertain.
UR - http://www.scopus.com/inward/record.url?scp=84962798435&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84962798435&partnerID=8YFLogxK
U2 - 10.1002/ana.24634
DO - 10.1002/ana.24634
M3 - Article
VL - 79
SP - 841
EP - 853
JO - Annals of Neurology
JF - Annals of Neurology
SN - 0364-5134
IS - 5
ER -