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Bilateral decreased oxygenation during focal status epilepticus in a neonate with hemimegalencephaly
Israel Alfonso1, Elza Vasconcellos, Hans H Shuhaiber
1Department of Neurology, Miami Children's Hospital, Florida, USA. ialfonso@mail.pediatricneuro.com
Insights
Early hemispherectomy benefits neonates with hemimegalencephaly and drug-resistant seizures. Surgery improves oxygenation in the remaining brain hemisphere, potentially preventing further neurological damage.
Area of Science:
- Neurology
- Pediatric Neurosurgery
Background:
- Hemimegalencephaly, a rare congenital brain malformation, often presents with medically intractable epilepsy in neonates.
- Tuberous sclerosis complex can be associated with hemimegalencephaly, posing significant management challenges.
Observation:
- Cerebral regional oxygen saturation index (rSO2) was monitored in a neonate with right hemimegalencephaly during seizures and after hemispherectomy.
- Epileptic seizures, even without overt clinical signs, caused significant fluctuations and declines in rSO2 across both cerebral hemispheres.
Findings:
- Surgery led to normalization of rSO2 in the non-dysplastic hemisphere post-hemispherectomy.
- The findings suggest that reduced oxygenation in the unaffected hemisphere during seizures may contribute to global neurological deficits.
Implications:
- Early hemispherectomy may be a crucial intervention for improving cerebral oxygenation and neurological outcomes in neonates with hemimegalencephaly.
- This approach could mitigate secondary neurological impairments by restoring adequate oxygen supply to the healthy brain hemisphere.
Abstract:
Early surgical removal of a dysplastic hemisphere appears to be beneficial for neonates with hemimegalencephaly and medically resistant seizures. We analyzed the changes in the cerebral regional oxygen saturation index in a neonate with tuberous sclerosis and right hemimegalencephaly (1) during seven episodes of right hemisphere electroencephalographic status epilepticus with and without clinical manifestations and (2) after right hemispherectomy. The cerebral regional oxygen saturation index demonstrated marked fluctuations and progressive decline in both hemispheres during the episodes and normal values in the remaining hemisphere after surgery. We speculate that decreased oxygenation of the nonepileptic cerebral hemisphere in patients with hemimegalencephaly and medically resistant seizures can contribute to the production of global neurologic impairments in these patients and that the benefits of early hemispherectomy are due to the improved oxygenation of the nondysplastic hemisphere following surgery.
