Doctors are telling Blaine that his next stunt could potentially make him go blind... for a limited period of time. The magician plans to hang upside down above New York's Central Park next week for 60 hours.
Dr. Massimo Napolitano, of Hackensack University Medical Center in New Jersey, said that hanging upside down for an extended period of time increases bloodpressure to the head, espically the eyes, which could lead to blindness.
Napolitano is advising Blaine on the stunt. The doctor is unsure how long the blindness could last, and said that the magician is also a risk for cramps and internal swelling.
The doctor said that Blaine's stunt to yeild valuble data for doctors.
So doctors, if your study is potentially unethical - bypass the ethics board by getting David Blaine to do it and just call it a "stunt."