PREDICTING EPILEPTOGENIC POTENTIAL OF BRAIN METASTASES BY GLUTAMATE ANALYSIS USING MAGNETIC RESONANCE SPECTROSCOPY: A RETROSPECTIVE STUDY
DOI:
https://doi.org/10.55766/sujst-2024-03-e03162Keywords:
Metabolites, MRS, Neuroexcitatory, Secondaries, SeizureAbstract
Background: Seizures are a common clinical manifestation of a primary or secondary brain tumor and epileptogenic brain secondaries from lung primaries cause significant morbidity around the world. Modern neuroimaging has revolutionized detailed anatomical evaluation of brain tumors but available literature is still scanty on prognosticating epileptogenic potential of brain lesions which if made available will be highly beneficial in making informed clinical decisions.This study is a step towards that endeavor.We in this study test the the correlation between Glutamate(Glu) levels in brain secondaries from lung primaries measured non-invasively with MRS as a measure of its epileptogenic potential. Methods: We retrospectively over a two year period reviewed clinical and imaging data of 150 patients with brain secondaries from lung primary at our institutions who underwent MRI brain either as part of work-up, seizure protocol or follow up. Brain tumoral Glutamate levels in epileptic and non-epileptic patients were analysed using MRS and its correlation with seizure potential was statistically analyzed using Fisher’s exact test to estimate overall effect. A p ≤ 0.05 was considered statistically significant. Results: Of 150 included patients, 57(38%) had seizures, out of which 49(85.6%, p<0.005) showed increase in their brain tumoral Glutamate peak amplitude on MRS which is a marker of increased concentration of this key neuroexcitatory neurotransmitter, thereby suggesting a direct and statistically significant linear correlation between intratumoral Glutamate levels and its epileptogenic potential. Conclusion: The findings of this study sheds light on the complex relationship between Glutamate levels within brain secondaries and its epileptogenic potential thereby advancing our understanding of the neurological implications of these lesions and projects MRS as a non-invasive tool in identifying the high risk group for targeted therapeutic interventions including prophylactic antiepileptic therapy.
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