Neuroimaging in drug resistant epilepsy

Namrita Sachdev, Shivani Gupta, Akhila Prasad


Background: Epilepsy is a common serious neurological condition and 30 to 40 % of people with epilepsy have seizures that are not controlled by medication. Patients are considered to have drug resistant epilepsy if disabling seizures continue despite appropriate trials of two anti-epileptic drugs. Most lesions causing drug resistant epilepsy can be detected by 3T MR Imaging using dedicated epilepsy protocol which is crucial for diagnostic and subsequent therapeutic planning with benefit from surgery. We present a review of the major abnormalities related to drug resistant epilepsy, highlighting the key findings of 3 T MRI.

Methods: A Cross-sectional Observational study was done in 30 patients. Patients less than 60 yrs of age of either sex, diagnosed with DRE as per ILAE criteria, were included in the study. 3T MRI was performed using dedicated epilepsy protocol, with additional 3D imaging for manual hippocampal volumetric evaluation.

Results: About 77% cases showed an MRI abnormality on visual assessment, with additional 16% cases showing abnormal MRI findings on manual hippocampal volumetry. Nearly 50% of the abnormal MRI cases showed Mesial Temporal Sclerosis, followed by neoplasms as etiology of DRE.

Conclusions: MR imaging has significantly improved detection of pathologies related to epilepsy, especially with the advent of epilepsy protocol. The total percentage of MRI abnormalities increased after incorporating manual hippocampal volumetry.


Drug Resistant Epilepsy, Magnetic Resonance Imaging, Mesial Temporal Sclerosis, LEATs, 3 T

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Kwan P, Arzimanoglou A, Berg AT, Brodie MJ, Allen Hauser W, Mathern G, et al. Definition of drug resistant epilepsy: consensus proposal by the ad hoc Task Force of the ILAE Commission on Therapeutic Strategies. Epilepsia. 2010 Jun;51(6):1069-77.

Zhang J, Liu W, Chen H, Xia H, Zhou Z, Mei S, et al. Multimodal neuroimaging in presurgical evaluation of drug-resistant epilepsy. Neuro Image: Clinical. 2014;4:35-44.

López González FJ, Rodríguez Osorio X, Gil-Nagel Rein A, Carreño Martínez M, Serratosa Fernández J, Villanueva Haba V, et al. Drug-resistant epilepsy: definition and treatment alternatives. Neurologia. 2015 Sep;30(7):439-46.

Boonluksiri P, Visuthibhan A, Katanyuwong K. Clinical Prediction Rule of Drug Resistant Epilepsy in Children. J Epilepsy Res. 2015;5(2):84-8.

Linda D, Mark C J. Managing Drug Resistant Epilepsy: challenges and solutions. Neuropsychiatr Dis Treatment. 2016;12:2605-16.

Oertzen TJV. Imaging and treatment decisions in seizures and epilepsy. EMJ Neurol. 2014;1:59-64.

Von Oertzen J, Urbach H, Jungbluth S, Kurthen M, Reuber M, Fernández G, et al. Standard magnetic resonance imaging is inadequate for patients with refractory focal epilepsy. J Neurol Neurosurg Psychiatr. 2002;73(6):643-7.

Farid N, Girard HM, Kemmotsu N, Smith ME, Magda SW, Lim WY, et al. Temporal lobe epilepsy: quantitative MR volumetry in detection of hippocampal atrophy. Radiology. 2012;264(2):542-50.

Anand KS, Dhikav V. Hippocampus in health and disease: An overview. Ann Indian Acad Neurol. 2012 Oct;15(4):239-46.

Kuzniecky R, Jackson GD. Magnetic resonance in epilepsy: neuroimaging techniques. 2nd ed. Academic Press; 2005 Jan 19.

Prado JÁ. Structural magnetic resonance imaging in epilepsy. Radiología (English Edition). 2012 Jan 1;54(1):9-20.

Mohandas AN, Bharath RD, Prathyusha PV, Gupta AK. Hippocampal volumetry: Normative data in the Indian population. Ann Indian Acad Neurol. 2014 Jul;17(3):267-71.

Farooque P, Hirsch l, Levy S, Testa F, Mattson R, Spencer D. Surgical outcome in adolescents with mesial temporal sclerosis: Is it different? Epilepsy Behav. 2017;69:24-7.

Urbach H. MRI of long term epilepsy associated tumors. Semin Ultrasound CT MR. 2008;22:350-79.

Osborn AG. Osborn’s Brain: Imaging, Pathology and Anatomy. 1st ed. Canada: Amirsys: 2013:1272.

Iwasaki M, Jin K, Nakasato N, Tominaga T. Non invasive evaluation for epilepsy surgery. Neurol Med Chir (Tokyo). 2016;56:632-40.

Raus I, Coroiu RE, Capusan CS. Neuroimaging in pediatric phakomatoses. An educational review. Clujal Med. 2016;89:56-64.