Brain temperature measured using proton MR spectroscopy detects cerebral hemodynamic impairment in patients with unilateral chronic major cerebral artery steno-occlusive disease: comparison with positron emission tomography.
OBJECTIVE
Brain temperature is determined by the balance between heat produced by cerebral energy turnover and heat removed by cerebral blood flow. The purpose of the present study was to investigate whether brain temperature measured noninvasively using proton MR spectroscopy can detect cerebral hemodynamic impairment in patients with unilateral chronic internal carotid or middle cerebral artery occlusive disease when compared with positron emission tomography.


METHODS
Brain temperature, cerebral blood flow, and metabolism were measured using proton MR spectroscopy and (15)O-positron emission tomography, respectively, in 21 normal subjects and 37 patients. Positron emission tomography images were coregistered with MR images and resliced automatically using image analysis software. Regions of interest placed in both cerebral hemispheres on MR images were automatically superimposed in these resliced positron emission tomography images.


RESULTS
A significant correlation was observed between brain temperature difference (affected hemisphere-contralateral hemisphere) and both cerebral blood volume and oxygen extraction fraction ratio (affected hemisphere/contralateral hemisphere; r=0.607; P=0.0004 and r=0.631; P=0.0002). With abnormally elevated cerebral blood volume or oxygen extraction fraction ratio defined as higher than the mean +2 SDs obtained from normal subjects, brain temperature difference provided 86% or 92% sensitivity and 87% or 84% specificity with 80% or 73% positive and 91% or 95% negative predictive values for detecting abnormally elevated cerebral blood volume or oxygen extraction fraction ratios, respectively.


CONCLUSIONS
Brain temperature measured using proton MR spectroscopy can detect cerebral hemodynamic impairment in patients with unilateral chronic major cerebral artery steno-occlusive disease.
Ishigaki
Daiya
D
Advanced Research Center, School of Medicine, Iwate Medical University, Morioka, Japan.
Ogasawara
Kuniaki
K
Yoshioka
Yoshichika
Y
Chida
Kohei
K
Sasaki
Makoto
M
Fujiwara
Shunrou
S
Aso
Kenta
K
Kobayashi
Masakazu
M
Yoshida
Kenji
K
Terasaki
Kazunori
K
Inoue
Takashi
T
Ogawa
Akira
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001831:Body Temperature; D002560:Cerebrovascular Circulation; D002908:Chronic Disease; D005260:Female; D006439:Hemodynamics; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D049268:Positron-Emission Tomography; D011859:Radiography; D012039:Regional Blood Flow