A woman in her 20's who was admitted to a hospital in China's Shandong Province gave doctors a surprise of a lifetime: she is missing a large and important part of her brain.
The woman was admitted to Shandong Province's Chinese PLA General Hospital of Jinan Military Area Command after complaining of dizziness and nausea. There, she told the doctors that she had problems with balance most of her life and that he mother said she did not start to walk until she turned 7 years old and that her speech was slurred as a child and only became intelligible when she turned 6.
Doctors learned what had been causing the problems after the woman underwent a CAT scan. They found that the woman does not have a cerebellum, the part of the brain associated with motor control and balance and is believed to be also involved in some cognitive functions such as speech. Also known as the "little brain", the cerebellum is about 10 percent of the total volume of the brain and contains 50 percent of its nerve cells.
Feng Yu, from the hospital's Department of Neurosurgery, and colleagues, who described the woman's bizarre case in an article published in the journal Brain on Aug. 22, revealed that the space where the cerebellum of the woman should have been does not have any tissue and is only filled with cerebrospinal fluid, a clear and colorless liquid that serves to cushion the brain and provides protection against disease.
"The patient presents with mild mental impairment and medium motor deficits," Yu and colleagues wrote. "CT and MRI scans revealed no remnants of any cerebellar tissues, verifying complete absence of the cerebellum."
The doctors said the woman has cerebellar agenesis, a rare condition characterized by the absence of the cerebellum. There are only nine known cases of cerebellar agenesis around the world and most of those who had the condition were only discovered after their early death.
People who have problems in their cerebellum often suffer from mental impairment, epilepsy and potentially fatal fluid build-up in the brain which raise their risks for premature death. The doctors are amazed that the woman survived to adulthood and only exhibited mild symptoms.
"These rare cases are interesting to understand how the brain circuitry works and compensates for missing parts," said Mario Manto, from the Free University of Brussels in Belgium, whose studies are focused on cerebellar disorders.