Slow vasomotor fluctuation in fMRI of anesthetized child brain.
Signal intensity changes in fMRI during rest caused by vasomotor fluctuations were investigated in this work. Resting-state baseline fluctuations were evaluated in 12 children anesthetized with thiopental. Five subjects had fluctuations related to subvoxel motion. In seven subjects without significant motion, slow signal fluctuation at 0.025-0.041 Hz near one or more primary sensory cortices was observed. In each subject the amplitude and frequency of the fluctuations were stable. It is hypothesized that thiopental, which reduces blood pressure and flow in the cortex, alters the feedback in neurovascular coupling leading to an increase in the magnitude and a reduction in the frequency of these fluctuations. The use of anesthesia in fMRI may provide new insight into neural connectivity and the coupling of blood flow and neural metabolism.
Kiviniemi
V
V
Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland. vkivinie@mail.student.oulu.fi
Jauhiainen
J
J
Tervonen
O
O
Pääkkö
E
E
Oikarinen
J
J
Vainionpää
V
V
Rantala
H
H
Biswal
B
B
D000771:Anesthesia, Intravenous; D016477:Artifacts; D001794:Blood Pressure / Q000187:drug effects; D001921:Brain / Q000033:anatomy & histology* / Q000098:blood supply* / Q000187:drug effects; D001927:Brain Diseases / Q000175:diagnosis; D002560:Cerebrovascular Circulation / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D009038:Motion; D019047:Phantoms, Imaging; D012815:Signal Processing, Computer-Assisted; D013003:Somatosensory Cortex / Q000033:anatomy & histology / Q000098:blood supply / Q000187:drug effects; D013874:Thiopental / Q000008:administration & dosage; D014666:Vasomotor System
D013874:Thiopental