Radiologic-pathologic correlation in focal cortical dysplasia and hemimegalencephaly in 18 children

Area of Science:

• Neurology
• Radiology
• Pathology

Background:

• Medically intractable epilepsy in children often requires surgical intervention.
• Focal cortical dysplasia and hemimegalencephaly are common pathologies in pediatric epilepsy.
• Accurate preoperative diagnosis is crucial for successful epilepsy surgery outcomes.

Purpose of the Study:

• To establish the radiologic-pathologic correlation in pediatric epilepsy surgery patients.
• To evaluate the accuracy of magnetic resonance imaging (MRI) in diagnosing cortical malformations.
• To correlate MRI findings with histopathological features of focal cortical dysplasia and hemimegalencephaly.

Main Methods:

• Retrospective review of MRI and pathology data from 18 children undergoing epilepsy surgery.
• Neuroradiologist reviewed preoperative MRIs blinded to radiologic diagnosis and pathology.
• Pathological examination included assessment of neuronal heterotopia, alignment, size, and cortical lamination.

Main Results:

• MRI accurately diagnosed the underlying cause in 16 out of 18 patients.
• Common MRI findings included abnormal gyral formation, cortical thickness, loss of gray-white differentiation, and T2-weighted signal abnormalities.
• Pathological findings frequently included neuronal heterotopia, neuronal misalignment, large neurons, and abnormal cortical lamination.

Conclusions:

• MRI demonstrates high accuracy in preoperative diagnosis for pediatric epilepsy surgery.
• Specific MRI characteristics correlate with underlying pathological features like neuronal heterotopia and abnormal cortical lamination.
• Understanding these radiologic-pathologic correlations can optimize surgical planning and improve outcomes in pediatric epilepsy.