Proton magnetic resonance spectroscopy in childhood brainstem lesions.
BACKGROUND
Diagnosis of brainstem lesions in children based on magnetic resonance imaging alone is a challenging problem. Magnetic resonance spectroscopy (MRS) is a noninvasive technique for spatial characterization of biochemical markers in tissues and gives information regarding cell membrane proliferation, neuronal damage, and energy metabolism.


METHODS
We measured the concentrations of biochemical markers in five children with brainstem lesions and evaluated their potential diagnostic significance. Images and spectra were acquired on a 1.5-T imager. The concentrations of N-acetylaspartate, tetramethylamines (e.g., choline), creatine, phosphocreatine, lactate, and lipids were measured within lesions located at the brainstem using Point-resolved spectroscopy sequences.


RESULTS
Diagnosis based on localized proton spectroscopy included brainstem glioma, brainstem encephalitis, demyelination, dysmyelination secondary to neurofibromatosis type 1 (NF 1), and possible infection or radiation necrosis. In all but one patient, diagnosis was confirmed by biopsy or by clinical follow-up.


CONCLUSIONS
This small sample of patients suggests that MRS is important in the differential diagnosis between proliferative and nonproliferative lesions in patients without neurofibromatosis. Unfortunately, in cases of NF 1, MRS can have a rather misdiagnosis role.
Porto
L
L
Neuroradiology Department, Klinikum der Johann Wolfgang Goethe-Universität, Schleusenweg 2-16, 60528 Frankfurt am Main, Germany. luciana.porto@kgu.de
Hattingen
E
E
Pilatus
U
U
Kieslich
M
M
Yan
B
B
Schwabe
D
D
Zanella
F E
FE
Lanfermann
H
H
D000293:Adolescent; D000596:Amino Acids / Q000378:metabolism*; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001923:Brain Chemistry / Q000502:physiology; D001927:Brain Diseases / Q000175:diagnosis* / Q000378:metabolism; D001933:Brain Stem / Q000378:metabolism* / Q000473:pathology; D020295:Brain Stem Neoplasms / Q000175:diagnosis / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D003711:Demyelinating Diseases / Q000175:diagnosis / Q000209:etiology / Q000378:metabolism; D003937:Diagnosis, Differential; D004660:Encephalitis / Q000175:diagnosis / Q000378:metabolism; D005260:Female; D005910:Glioma / Q000175:diagnosis / Q000378:metabolism; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D017253:Neurofibromatoses / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism; D011522:Protons
D000596:Amino Acids; D011522:Protons; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline