Crossed cerebellar diaschisis: a positron emission tomography study with L-[methyl-11C]methionine and 2-deoxy-2-[18F]fluoro-D-glucose.
OBJECTIVE
Crossed cerebellar diaschisis (CCD) is defined as a depression of blood flow and oxidative metabolism of glucose in the cerebellum contralateral to a supratentorial brain lesion, as detected with positron emission tomography (PET) and single photon emission computed tomography. We examined whether L-[methyl-11C]methionine (MET) uptake is affected in CCD.


METHODS
In 12 patients with a unilateral supratentorial brain tumor, we evaluated the uptake of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) and MET in the cerebellar hemispheres by means of PET. Asymmetry index (AI) was defined as a difference in the average count between the ipsilateral and contralateral cerebellar hemispheres divided by the average count in both cerebellar hemispheres. Patients with AI of FDG PET more than 0.1 and those with AI equal to 0.1 or less than 0.1 were classified as CCD-positive and CCD-negative, respectively.


RESULTS
Six patients were CCD-positive and others were CCD-negative in the FDG PET study. Between CCD-positive and CCD-negative patients, mean AI of MET was not significantly different (0.017 +/- 0.023 and 0.014 +/- 0.039, respectively).


CONCLUSIONS
Different from glucose metabolism, cerebellar MET uptake was not affected in CCD. The present study may indicate that cerebellar MET uptake is independent of suppression of cerebellar neuronal activity.
Kajimoto
Katsufumi
K
Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita, Japan.
Oku
Naohiko
N
Kimura
Yasuyuki
Y
Kato
Hiroki
H
Tanaka
Makiko Rai
MR
Kanai
Yasukazu
Y
Kitagawa
Kazuo
K
Maruno
Motohiko
M
Yoshimine
Toshiki
T
Hori
Masatsugu
M
Hatazawa
Jun
J
D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism; D002526:Cerebellar Diseases / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002531:Cerebellum / Q000098:blood supply / Q000000981:diagnostic imaging / Q000378:metabolism; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D008715:Methionine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D008715:Methionine; C038344:methionine methyl ester