title: Proton MRS of the peritumoral brain.
abstract: Long-echo (TR: 2000 ms, TE: 136 ms) proton MRS of the cerebral tissue in the vicinity to intracranial lesion was done in 15 patients, mainly with parenchymal brain tumors. Significant decrease of N-acetylaspartate (NAA) (P<0.001) and more frequent presence of lactate (P<0.01) comparing with distant normal white matter were found in the perilesional brain tissue. The level of NAA in the perilesional brain tissue had negative associations with presence of lactate in the lesion (P<0.05), excess of lactate in the lesion compared to perilesional brain (P<0.01), grade of the perilesional edema (P<0.01) and patient's age (P<0.05). Multivariate analysis disclosed that identification of lactate in the lesion is associated with lower relative NAA content in the perilesional brain tissue, independently on the presence or absence of any other factor, including brain edema (P<0.001). In patients with lobar lesions who had at least one epileptic seizure during course of their disease the relative NAA content in the perilesional brain was significantly lower, comparing with those who were seizure-free (P<0.05). Therefore, lactate diffused from the tumor, or other metabolites secreted by lactate-producing neoplasm, should be considered as important contributors to the neuronal dysfunction in the surrounding brain. Decrease of NAA in the vicinity to intracranial lesions may reflect neuronal alteration responsible for associated epilepsy.
authors.affiliation: Department of Neurosurgery, Neurological Institute, Tokyo Women's Medical University, Tokyo 162-8666, Japan. m_chernov@yahoo.com
authors.forename: Mikhail F
authors.initials: MF
authors.lastname: Chernov
authors.forename: Osami
authors.initials: O
authors.lastname: Kubo
authors.forename: Motohiro
authors.initials: M
authors.lastname: Hayashi
authors.forename: Masahiro
authors.initials: M
authors.lastname: Izawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Maruyama
authors.forename: Masao
authors.initials: M
authors.lastname: Usukura
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ono
authors.forename: Tomokatsu
authors.initials: T
authors.lastname: Hori
authors.forename: Kintomo
authors.initials: K
authors.lastname: Takakura
mesh_terms: D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000378:metabolism*; D001921:Brain / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D001929:Brain Edema / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000378:metabolism* / Q000503:physiopathology; D004827:Epilepsy / Q000209:etiology / Q000378:metabolism; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000032:analysis / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009413:Nerve Fibers, Myelinated / Q000378:metabolism / Q000473:pathology; D011237:Predictive Value of Tests; D011522:Protons
chemical_list: D014408:Biomarkers, Tumor; D011522:Protons; D001224:Aspartic Acid; D019344:Lactic Acid; C000179:N-acetylaspartate