11.   The Croatian president underwent medical tests in Washington, D.C. late last month.

12.   The former South African president is undergoing radiation treatment for prostate cancer.

13.   The president underwent a medical checkup Wednesday at the Central Clinical Hospital in Moscow that had been scheduled before he came down with his recent illness, Yakushkin said.

14.   The president underwent a tracheotomy in Innsbruck after phlegm blocked his windpipe.

15.   The president underwent surgery in Switzerland in August.

16.   The president will undergo routine tests on his intestine, which was damaged in the attack.

17.   The president underwent emergency surgery for a ruptured colon and acute peritonitis in early April while vacationing in the Austrian Alps.

18.   The president underwent tracheotomy in Innsbruck after phlegm blocked his windpipe.

19.   The president underwent a medical checkup Wednesday at the Central Clinical Hospital in Moscow that had been planned before he came down with his latest illness, Yakushkin said.

20.   The president underwent cancer surgery in Switzerland in August.