Can a seizure cause abnormalities on the brain MRI?

Yes it can, and the MRI abnormalities could represent seizure’s effects on the brain, not the seizure’s structural cause. Seizure-related MRI changes are often associated with status epilepticus, but have also been reported in complex partial status epilepticus.1,2

T2-weighted MRI images may show increased signal intensity at the cortical gray matter, subcortical white matter, or hippocampus. The MRI changes are unilateral about one-half of the cases, while in about 8% of patients leptomeningeal contrast-enhancement may be observed. Partial simple and complex seizures are associated with hippocampal involvement.3

The increased signal intensity following seizures is thought to be due to increased metabolism at the epileptogenic area, which in turn results in increased oxygen consumption, hypoxia, hypercarbia, lactic acidosis, and ultimately vasodilation and edema.

Reversibility of MRI changes following seizures has been noted between 15 and 150 days (average, 62 days). A structural abnormality is more likely the cause of a seizure when the MRI changes do not resolve during this period.3 Therefore, seizure-induced brain-MRI abnormalities remain a diagnosis of exclusion.

References

  1. Kim JA, Chung JI, Yoon PH, et al. Transient MR signal changes in patients with generalized tonicoclonic seizure or status epilepticus: periictal diffusion-weighted imaging. Am J Neuroradiol 2001; 22:1149–1160 http://www.ajnr.org/content/22/6/1149.long
  2. Henry TR, Brunberg DI, Pennell PB, et al. Focal cerebral magnetic resonance changes associated with partial status epilepticus. Epilepsia 1994; 35:35–41 http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.916.5237&rep=rep1&type=pdf
  3. Cianfoni A, Caulo M, Cerase A, et al. Seizure-induced brain lesions: a wide spectrum of variably reversible MRI abnormalities. Eur J Radiol. 2013; 82(11):1964-72. http://www.ejradiology.com/article/S0720-048X(13)00271-4/fulltext

 

Contributed by Johan H.L. Boneschansker, MD, Mass General Hospital, Boston, MA.

Can a seizure cause abnormalities on the brain MRI?

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