Post-surgical effects on language in patients with presumed low-grade glioma.

OBJECTIVES: Low-grade glioma (LGG) is a slow-growing brain tumour often situated in or near areas involved in language and/or cognitive functions. Thus, language impairments due to tumour growth or surgical resection are obvious risks. We aimed to investigate language outcome following surgery in patients with presumed LGG, using a comprehensive and sensitive language assessment. MATERIALS AND METHODS: Thirty-two consecutive patients with presumed LGG were assessed preoperative, early post-operative, and 3 months post-operative using sensitive tests including lexical retrieval, language comprehension and high-level language. The patients' preoperative language ability was compared with a reference group, but also with performance at post-operative controls. Further, the association between tumour location and language performance pre- and post-operatively was explored. RESULTS: Before surgery, the patients with presumed LGG performed worse on tests of lexical retrieval when compared to a reference group (BNT: LGG-group median 52, Reference-group median 54, P = .002; Animals: LGG-group mean 21.0, Reference-group mean 25, P = 001; Verbs: LGG-group mean 17.3, Reference-group mean 21.4, P = .001). At early post-operative assessment, we observed a decline in all language tests, whereas at 3 months there was only a decline on a single test of lexical retrieval (Animals: preoperative. median 20, post-op median 14, P = .001). The highest proportion of language impairment was found in the group with a tumour in language-eloquent areas at all time-points. CONCLUSIONS: Although many patients with a tumour in the left hemisphere deteriorated in their language function directly after surgery, their prognosis for recovery was good.

Cerebral amino acids and energy metabolites in the growth retarded rat fetus under normoxia and hypoxia.

The effect of intrauterine growth retardation (IUGR) on striatal energy metabolites and amino acid concentrations was studied in the fetuses of eight nulliparous rat dams after uterine artery ligation on day 18 of gestation. On day 22 (term = 23), four dams were subjected to normoxia and four to hypoxia (10% oxygen) for 58 min, while monitoring hemodynamics and blood gases. After decapitation of the dam, fetuses were delivered by sectio and decapitated. The measured parameters in the dams were stable under normoxia but exhibited decreased oxygen availability under hypoxia. Striatal energy balance was preserved in IUGRs, both under maternal normoxic and hypoxic conditions, compared to appropriately grown (AGA) littermates. Under maternal normoxia, the striatal concentration of aspartate was reduced (P < 0.01) in IUGRs and the level of alanine was increased (P < 0.01) as compared to AGAs. Under hypoxia, the level of GABA was higher in IUGRs (P < 0.01). Lactate was increased in all fetuses under hypoxia. It is concluded that striatal energy metabolism is preserved in IUGR rat fetuses in late gestation under both maternal normoxia and hypoxia. Amino acid metabolism, however, is disturbed and depends on the degree of growth retardation and on the severity of perinatal stress.