Progressive supranuclear palsy
"Why do we have an aunt who is so scared of falling backwards?" — writer Julio Cortázar
In his short story "Uncle in Trouble," the Argentinean writer Julio Cortázar describes how a family accommodates an aunt who sits and lies stiffly, moves only after great hesitation, takes several minutes to cross a room, and has difficulty aiming her eyes. Although Cortázar's writing often borders on the surreal, a neurologist suggested that this story actually provides a realistic description of progressive supranuclear palsy (PSP), a relatively uncommon, fatal brain disease that is often initially diagnosed as Parkinson's disease. The first symptoms strike in midlife, between ages 50 and 70.
The hallmark of PSP is difficulty in aiming the eyes up and down, caused by damage in an area of the brainstem that lies above (supra) clusters of nerve cells (nuclei) that control eye movements. However, telltale vision problems may not show up until after the onset of other symptoms — for example, an unsteady gait or falls — that overlap those of more common neurological diseases, such as Parkinson's and Alzheimer's. This can lead to years of frustrating misdiagnoses and treatments that don't help and may be harmful. Up to 5% of people with Parkinson's-type symptoms, including rigidity, tremor, and balance problems, may actually have PSP. Conversely, a study of postmortem brain samples from people thought to have PSP found that 30% actually had one of several rarer brain disorders.