Symptoms
Removal of a complete hemisphere of the brain (unilateral brain amputation) during hemispherectomy leads to severe functional deficits after the operation. Thus, the centers for certain skills are often located in only one of the two hemispheres of the brain. For example, the speech center in most people is located in the left hemisphere, while spatial awareness is usually represented by the right hemisphere.
In healthy people, the two hemispheres of the brain also control the motor and sensory functions of the opposite hemisphere. As a result, after a right-sided brain amputation, paralysis and loss of sensitivity or even vision on the left side occurs and vice versa. Correspondingly, the functional restrictions are less severe after removal of only individual brain lobes (lobectomy).
Consequences
Due to the serious functional deficits described above following a partial brain amputation, such an intervention should only be performed in patients for whom, on the one hand, no promising alternative treatment option is available and, on the other hand, there is the prospect that the partial brain amputation can lead to a strong improvement in the symptoms of the disease and thus an overall improvement in quality of life. In fact, many patients with therapy-resistant epilepsy, especially those with underlying Sturge Weber syndrome, benefit significantly from a partial brain amputation. The frequency and intensity of epileptic seizures decreases while intellect and communication skills increase.
Especially young patients up to primary school age are suitable patients for such an operation, as they still have sufficient ability to restructure their brain tissue. Thus, after hemispherectomy or lobectomy, the remaining hemisphere of the brain or the remaining brain lobes can at least partially take over the functions of the removed tissue.However, this requires intensive training, which must be started under expert supervision and continued in the long term to counteract the consequences of brain amputation. In this way, it may even be possible to compensate for all functional failures, so that the patient can finally live completely without any failures in adulthood.
The removal of the so-called focus, i.e. the lobe or hemisphere of the brain from which the epileptic seizures originate, is not only to be regarded as symptomatic treatment. This means that the seizures are not only an extremely unpleasant symptom of a disease, but also cause further brain damage themselves. This damage is insignificant for most epileptics, as they are often completely seizure-free under treatment with antiepileptic drugs or suffer only a few seizures a year. In patients with Rasmussen’s encephalitis or Sturge Weber syndrome, on the other hand, seizures occur significantly more frequently and can thus lead to structural brain damage in the long term. Therefore, partial brain amputation is more likely to be considered in these diseases.
