Supranuclear Palsy is relatively rare disease that causes balance, muscle and coordination problems. The fact that there is no definitive test for it means they're taking lots of tests to rule out other possible disorders. They'll want to keep a close eye on you because while there's no cure for it there are some treatments that may help slow the disease.
According to what I've read you should engage in as much safe exercise as you can, try to keep your mind active with stimulating mental activity (crossword puzzles, games, reading, etc.) and try to stay active socially. Research has shown that these types of activities strengthen the neuron connections in the brain.
You should also be on a low protein diet and eat plenty of fruits and vegetables.
You might also check out this national support group for this disorder.
http://www.psp.org/
For more information
http://www.emedicinehealth.com/progressive_supranuclear_palsy/article_em.htm
Good luck!