Quantitative changes in regional cerebral blood flow induced by cold, heat and ischemic pain: a continuous arterial spin labeling study.
BACKGROUND
The development of arterial spin labeling methods has allowed measuring regional cerebral blood flow (rCBF) quantitatively and to show the pattern of cerebral activity associated with any state such as a sustained pain state or changes due to a neurotropic drug.


METHODS
The authors studied the differential effects of three pain conditions in 10 healthy subjects on a 3 Tesla scanner during resting baseline, heat, cold, and ischemic pain using continuous arterial spin labeling.


RESULTS
Cold pain showed the greatest absolute rCBF increases in left anterior cingulate cortex, left amygdala, left angular gyrus, and Brodmann area 6, and a significant rCBF decrease in the cerebellum. Changes in rCBF were characteristic of the type of pain condition: cold and heat pain showed increases, whereas the ischemic condition showed a reduction in mean absolute gray matter flow compared with rest. An association of subjects' pain tolerance and cerebral blood flow was noted.


CONCLUSIONS
The observation that quantitative rCBF changes are characteristic of the pain task used and that there is a consistent rCBF change in Brodman area 6, an area responsible for the integration of a motor response to pain, should provide extremely useful information in the quest to develop an imaging biomarker of pain. Conceivably, response in BA6 may serve as an objective measure of analgesic efficacy.
Department of Anesthesiology, University of Alabama at Birmingham, Birmingham, Alabama, USA. froelich@uab.edu
Michael A
MA
Frölich
Hrishikesh
H
Deshpande
Timothy
T
Ness
Georg
G
Deutsch
D000328:Adult; D000465:Algorithms; D002560:Cerebrovascular Circulation / Q000502:physiology*; D016000:Cluster Analysis; D003080:Cold Temperature; D005260:Female; D006358:Hot Temperature; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007511:Ischemia / Q000150:complications / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology / Q000503:physiopathology*; D017288:Pain Threshold / Q000502:physiology; D013113:Spin Labels; D055815:Young Adult
D013113:Spin Labels