You're an eye specialist, and one of your patients reports that a lens in his eye - which you put in following a cataract operation - has been displaced after he was struck in the face. An outpatient procedure, involving eyedrops, has failed to put the lens back into position.
So what do you do next? You have the option of surgery - or you could suggest that he go on a rollercoaster ride.
Rollercoasters could become standard treatment after one 19-year-old man, with just such a displaced lens, went on one of Europe's largest rollercoaster rides on the weekend before he was due to go in for surgery.
The ride reached a height of 73 m and a speed of 130 km, at which point, the rider is exposed to a 4G force. After he came off the ride, he noticed that his vision was normal and that his pupil had returned to its usual shape (N Engl J Med, 2003; 349: 1094-6).