It may seem like a nineteenth-century treatment, but the removal of a part of the brain is today the only possibility for those with severe epilepsy and do not respond to drugs
The effect is immediate. After the delicate operation, the epileptic seizures disappear immediately and the majority of patients do not register important sequelae. Magic? No, hemispherectomy. That is the removal or separation of much of the affected cerebral hemisphere and its disconnection to the rest of the body’s tissues.
Although it is not too common, its therapeutic use is increasingly settled in those patients who suffer from severe epilepsy and do not react to drugs. Not only are the effects on epilepsy striking but their consequences are bearable thanks to the plasticity of our most important vital organ. Living with a half brain is possible and, for those who have gone through this surgery, it has been a huge leap forward in their quality of life.
All this is no stranger to the neurologists of the University Hospital of Santiago de Compostela, one of the most reputable Spanish centres in this type of intervention. “Hemispherectomy is a surgery that is applied only in severe cases of epilepsy, ” Xiana Rodríguez Osorio, a neurologist at the Galician hospital and one of the authors of a hemispherectomy study published last year in ‘Revista de Neurología’, explains “Most epileptics respond well to treatment but there are 20-30% that don’t, and that’s where you have to see if there are surgical alternatives to drugs.”
In their work, the hospital researchers detailed the follow-up of five patients who underwent this surgery between 1999 and 2010. Unlike the Americans, not all were children when they went through the operating room: the oldest of them already had 32 years and had been with epilepsy since the three However, practically everyone has become crisis-free after 15 years of follow-up. And those who have not, have seen their situation improved by up to 90% compared to before the operation.
“The brain is an organ that is superorganized and super structured, we know that certain functions are in certain areas: the vision in the occipital lobe, the motor in the frontal … what happens? That the brain’s ability to learn human during the first years is very large and then not only the neurons but the connection between them can mark that a function is carried out with greater or lesser precision,” adds further. “The development of these connections between neurons allows complementing those functions that may be failing for some medical reason.”
US researchers recently published a study in ‘Cell Reports’ where they followed several teenagers who went through this operation as young people. The most curious thing is not only that their brain halves are as functional as the entire brains of the control group, but that they show even greater connectivity between their neural networks.
“In epilepsy surgery, it is important that if the patient is very small, the surgical possibility is evaluated as soon as possible because having repeated crises can also affect the cognitive development of the person,” says the neurologist. In this way, the cognitive abilities of many of these children who have been operated at a young age are practically indistinguishable from others with a full brain.
In short, we are not only learning how to overcome these severe cases of epilepsy, but we are also learning things we did not even imagine about the brain. When Ahad Israfil, a young American from Dayton, Ohio, was shot in the head in 1987 that shattered his skull and half a brain, no one imagined that 1) he would survive and 2) he would recover all his cognitive functions except a loss of mobility that He prostrated him in a wheelchair until his death two months ago. Today, scientific works like these help explain his miraculous recovery.
To remove to disconnect
In recent years, what is attempted is not to remove a part of the brain but simply to disconnect it from the rest. “It was seen that leaving cavities inside the brain was not good,” says Rodríguez Osorio, “so it is tried to simply separate it from the rest so that those crises do not spread and the result for epilepsy is usually just as good in this type. of interventions when they are well indicated.”
It is what is known as functional hemispherectomy: the damaged half is still there, but it is as if it were not there.
So far everything seems very simple, but the plasticity of the brain cannot do everything. When one disconnects apart, there are several functions that can be affected, for example, mobility in the hand on the opposite side. “The surgery is very good for people who, in addition to epilepsy and being drug-resistant, already have important functions compromised,” says the neurologist.
According to the experience of these researchers in Santiago de Compostela, a reasonable time – a couple of weeks – is enough to recover from an acute operation like that. Sometimes they require some rehabilitation if there have been small losses in motor or language function, something that is not usual either.