In 2015, a team of neurologists and radiologists from Jinan Hospital in Shandong Province, China, wrote to the journal Brain reporting a rare and unusual finding. A 24-year-old female patient was admitted with symptoms of dizziness and vomiting. These were new symptoms, but she had also suffered from dizziness and difficulty walking for most of her life.
Despite these challenges, the lady was married and had a successful pregnancy. Doctors referred her for computed tomography (CT) and magnetic resonance imaging (MRI) scans to look for the cause of these symptoms in the brain.
What they noticed was a disorder so rare that fewer than ten people worldwide were known to live with it. The patient was completely missing her cerebellum. This is a special structure located at the back of the brain. It occupies only approximately ten percent of the brain's volume, but contains a dense abundance of neurons estimated to be over 50 percent of the total neurons in the brain.
Together, these neurons work to coordinate motor actions, allowing us to walk with balance and speak accurately. Despite the integral function of the cerebellum, sufferers of cerebellar agenesis – where the structure is completely absent – are sometimes able to develop normally in addition to impaired motor functions. Loss of brain tissue can also be seen in those suffering from hydrocephalus, a condition where cerebrospinal fluid builds up in the brain.
In extreme cases, the fluid can build up to such an extent that it doesn't leave much room in the skull for anything else, including the mass of the brain. In Marseille, France, a 44-year-old man was found to be suffering from a case of hydrocephalus so severe that he was estimated to be missing over 50 percent of his brain tissue. And yet, the man had lived a relatively normal life, holding down a job and raising a family, which speaks to the brain's remarkable ability to adapt and use what tissue it has to perform the necessary functions. .
*first published on bota.al
