Ictal ^99mTc-Ethyl Cysteinate Dimer SPECT Findings of a Girl With Refractory Localization-Related Epilepsy Who Developed Transient Ictal Bradycardia

Area of Science:

• Neurology
• Cardiology
• Epileptology

Background:

• Ictal bradycardia is a rare but serious complication of epilepsy, implicated in sudden unexplained death in epilepsy.
• Focal cortical dysplasia is a common cause of intractable epilepsy, particularly in children.

Purpose of the Study:

• To investigate the potential mechanism of ictal bradycardia in a pediatric patient with focal cortical dysplasia.

Main Methods:

• Case report of a 10-year-old girl with focal cortical dysplasia.
• Brain MRI to identify structural abnormalities.
• Ictal 99mTc-ethyl cysteinate dimer single-photon emission computed tomography (SPECT) to assess cerebral blood flow during seizures.

Main Results:

• The patient experienced transient ictal bradycardia during cluster seizures.
• MRI revealed a high signal intensity lesion adjacent to the focal cortical dysplasia.
• Ictal SPECT demonstrated hyperperfusion in an area near the insular cortex, encompassing the high signal intensity lesion.

Conclusions:

• The findings suggest that seizure propagation to the insular cortex, potentially involving the identified lesion, may cause ictal bradycardia.
• This case highlights a possible mechanism linking focal cortical dysplasia, insular cortex involvement, and cardiac rhythm disturbances during seizures.