Apparent relative hypermetabolism of selective brain areas in Huntington disease and importance of reference region for analysis.
OBJECTIVE
We investigated the pattern of reduced and increased metabolism in symptomatic Huntington chorea (HD) patients and assessed the influence of intensity normalization method.


METHODS
FDG brain PET was performed in 11 manifest HD patients and 11 age-matched controls. Images underwent statistical parametric mapping analysis after global normalization or with white matter or pons as reference region. Region of interest analysis of FDG uptake ratios was also performed using total region or white matter as reference. Correlation between regional uptake ratios to that of the caudate was evaluated by linear regression analysis.


RESULTS
Although statistical parametric mapping analysis identified striatal hypometabolism and thalamic hypermetabolism in HD patients with all methods, substantially different FDG uptake patterns were shown depending on the method of intensity normalization. Global normalization displayed large areas of relative normalized hypermetabolism across the cerebral cortex and cerebellum. With white matter as reference, relative normalized hypermetabolism was observed in the thalamus and a much more limited area of the cortex. With pons as reference, relative normalized hypermetabolism was largely confined to the thalamus and a small area of the cerebellum.


CONCLUSIONS
These results demonstrate apparent relative normalized hypermetabolism in selective brain regions in manifest HD patients. Furthermore, the choice of reference region for intensity normalization is critical for accurate monitoring of this metabolic change with FDG PET.
Department of Nuclear Medicine, Ajou University School of Medicine, Suwon, Korea.
Su Jin
SJ
Lee
Won Yong
WY
Lee
Yu Kyeong
YK
Kim
Young-Sil
YS
An
Jin Whan
JW
Cho
Joon Young
JY
Choi
Byung-Tae
BT
Kim
Kyung-Han
KH
Lee
D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D001931:Brain Mapping; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D006816:Huntington Disease / Q000000981:diagnostic imaging / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D012015:Reference Standards
D019788:Fluorodeoxyglucose F18