Hemispherectomy: When Half a Brain Is Better than a Whole One

Introduction

Hemispherectomy is a very rare neurological procedure which involves total or partial removal of an affected cerebral hemisphere or removing/disconnecting the affected part from the unaffected part. It is a rare neurological procedure which is used to treat the variety of seizure disorders where the source of the epilepsy is localized to a wide region of a single hemisphere of the brain, notably Rasmussen's encephalitis

Rasmussen's encephalitis, maybe an uncommon inflammatory neurological disease, characterized by the visit and serious seizures, the loss of motor skills and speech, hemiparesis (weakness on one side of the body), encephalitis (inflammation of the brain), and dementia. The illness influences a single cerebral hemisphere and generally happens in children beneath the age of 15.

Almost one in three patients with epilepsy will proceed to have persistent seizures despite epileptic drug treatment. Hemispherectomy is reserved for the foremost extreme cases of this one-third in which the individual’s seizures are irresponsive to drugs or other less intrusive surgeries and essentially disable working or put the patient at the chance of further complications. The method effectively cures seizures in around 85%-90% of patients. Furthermore, it is additionally known to often uniquely improve the cognitive functioning and improvement of the individual. Subtotal hemispherectomy sparing sensorimotor cortex can be performed with successful seizure control expected in 70-80% of patients. Indeed with the presence of widespread one-sided epileptogenicity or anatomic/functional imaging anomalies, complete hemispherectomy can regularly be avoided, especially when there's little hemiparesis.

The removal of half brain sounds too radical to ever consider, much less perform. In the last century, many surgeons have performed it hundreds of times for disorders uncontrollable in another way. Unbelievably, the surgery has no apparent effect on personality or memory. The first known hemispherectomy was performed in dogin 1888 by a German Physiologists Friedrich Goltz.

What patients are appropriate for a hemispherectomy?

1. Medically intractable epilepsy with seizures arising from the pathological side.

2. The weakness of one side of the body with loss of dexterity of the hand with, or without, peripheral vision loss.

3. Developmental retardation or arrest of maturation due to intractable seizures.

4. Diffuse abnormality of one cerebral hemisphere which is contributing to intractable epilepsy.

What are the various types of hemispherectomy?

There are two types of hemispherectomy which is commonly performed.

Anatomical hemispherectomies include the removal of the frontal, parietal, temporal, and occipital lobes., though useful hemispherectomies only take out parts of a hemisphere, as well as separating the corpus callosum, the fiber bundle that connects the two parts of the brain. The deeper structures like basal ganglia, thalamus and brain stem are left in place.The evacuated cavity is left empty, filling with cerebrospinal liquid in a day or so. It is performed in the case of hemimegalencephaly.

The functional technique involves the removal of a smaller area of the affected hemisphere and disconnecting it from the remaining brain tissue.

Potential Complications of Hemispherectomy in Children

·         Nausea

·         Fatigue

·         Depression

·         Headache

·         Difficulty with speech and memory

·         Neuropsychological tests will be performed to detect any changes in your child’s function

·         Scalp numbness