Neurology ® Clinical Practice Neuroimaging of first-ever seizure: Contribution

of MRI if CT is normal Nitin K. Sethi, MD: I read with interest the study by Ho et al.1 on the contribution of MRI scan in the diagnostic management of first-ever seizure. Standard MRI may fail to detect potential focal epileptogenic lesions and thus MRI using a dedicated epilepsy protocol such as that performed at epilepsy surgery centers is recommended nowadays.2 That it is superior to CT scan to detect potential epileptogenic lesions is well-established and the Ho et al. study attests to this. However, one should not forget a few situations such as a calcified neuro-cysticercosis lesion where a CT scan may have superior sensitivity for lesion detection.3 When a potential epileptogenic lesion is detected on MRI, whether it is the culprit lesion or an incidental finding needs to be determined, for patients can harbor dual pathologies such as mesial temporal sclerosis and focal cortical dysplasia.4 With rapid advances occurring in MRI technology, we can soon expect to have higher resolution MRI scans with more sensitive imaging protocols. The Ho et al. study helps reinforce the importance of EEG in the “neuro-imaging ” of first-ever seizure. Concordance of EEG and MRI findings is paramount for establishing the true epileptogenic potential of the lesion