Low-grade glioma or post-ictal change? MR spectroscopy to the rescue!

<h3></h3> The overlapping radiological features of low-grade glioma (LGG) and post-ictal change can pose significant diagnostic uncertainty amongst clinicians, especially as seizures are the most common presentation of LGG. Quick and accurate differentiation is important to avoid further unnecessary and risky invasive investigations, such as brain biopsy. We report a case of post-ictal frontotemporal changes, mimicking LGG, where MR spectroscopy was pivotal in narrowing the differential diagnosis and guiding further management. A 52-year-old with a history of generalized tonic-clonic seizures, well managed on lamotrigine, presented acutely with frequent right sided facial motor seizures. MRI at initial presentation demonstrated left-sided T2-FLAIR oedematous hyperintensity, predominantly in the insular cortex and adjacent sylvian fissure. The differential diagnoses considered at this point were LGG , atypical infarction or ischaemia and mitochondrial disease. Repeat imaging 2 weeks later failed to clarify the diagnostic picture. MR Spectroscopy was performed which showed dramatic resolution of the T2 hyperintense gyral expansion and no characteristic metabolic features of LGG. The patient was consequently managed with increased antiepileptic medications and remained seizure free. This case strongly demonstrates the utility of multimodal MR imaging, particularly when seizures are apparent at presentation, and when signal change is present in atypical locations.