Hemispherectomy is a rare but effective surgical treatment for Epilepsy and Seizures, primarily used in severe cases where seizures are not controlled by medication. This procedure involves removing or disconnecting one cerebral hemisphere (half of the brain) to eliminate the seizure focus. Hemispherectomy is typically considered for children with catastrophic epilepsy conditions, such as Rasmussen’s encephalitis, Sturge-Weber syndrome, or hemimegalencephaly, where seizures originate from extensive damage to one hemisphere. Despite the removal or disconnection of a significant portion of the brain, patients can often recover function remarkably well due to the brain’s plasticity, especially in young children.

The hemispherectomy procedure involves two main approaches: anatomical and functional. Anatomical hemispherectomy involves removing the affected cerebral hemisphere, while functional hemispherectomy disconnects the affected hemisphere from the rest of the brain but leaves most of the tissue in place. The surgery requires general anaesthesia and can take several hours. Surgeons access the brain through a craniotomy (opening the skull) and meticulously remove or disconnect the problematic hemisphere, ensuring minimal damage to critical brain structures. Post-surgery, patients are monitored in an intensive care unit before moving to a rehabilitation program.

Eligibility for hemispherectomy is determined based on several criteria. Candidates are usually children with severe, intractable epilepsy that does not respond to multiple anti-seizure medications. The seizures typically originate from one hemisphere and are associated with conditions like Rasmussen’s encephalitis, Sturge-Weber syndrome, or hemimegalencephaly. Extensive preoperative evaluations, including MRI, EEG, and neuropsychological assessments, are conducted to ensure that the seizures are localised to one hemisphere and that the opposite hemisphere is sufficiently healthy to compensate for the lost functions. Patients must also have a high likelihood of significant improvement in seizure control post-surgery.

The primary benefit of hemispherectomy is the substantial reduction or complete elimination of seizures in patients who previously had intractable epilepsy. For many, this dramatic improvement in seizure control leads to enhanced quality of life, better cognitive development, and increased independence. The surgery can also reduce or eliminate the need for anti-seizure medications, which often come with significant side effects. Additionally, stopping seizures can prevent further brain damage and cognitive decline, allowing for improved learning and developmental progress, especially in young children whose brains are still highly plastic.

Hemispherectomy, like any major brain surgery, carries significant risks. Immediate surgical risks include bleeding, infection, and complications from anaesthesia. Long-term risks can involve hemiparesis (weakness on one side of the body), hemianopia (loss of half of the visual field), and cognitive or language difficulties, depending on which hemisphere is removed or disconnected. There is also the possibility of hydrocephalus, requiring a shunt to drain excess cerebrospinal fluid. Despite these risks, the procedure’s potential to significantly reduce or eliminate debilitating seizures often outweighs the potential drawbacks for eligible patients.

Recovery from hemispherectomy involves an extended period of hospitalisation followed by intensive rehabilitation. Initial recovery includes close monitoring in an intensive care unit to manage pain, prevent infection, and monitor neurological function. As patients stabilise, they transition to a rehabilitation facility where they undergo physical, occupational, and speech therapy to help regain motor skills, compensate for deficits, and adapt to changes in cognitive functions. Recovery times vary, but children typically show significant improvements within months, with ongoing progress over years. Long-term follow-up is essential to monitor for potential complications and to support continued development and adaptation.