Here’s a photograph from the December 11 1930 edition of the Toronto Daily Star of an ophthalmologist who was going to perform eye surgery on the King of Siam.
Prajadhipok (1893-1941), also known as Phra Pok Klao Chao Yu Hua or Rama VII, was the King of Siam (as it was then known) from 1925 to 1935. As a result of a revolution in 1932, he became a constitutional monarch instead of an absolute monarch; he abdicated in 1935 over disputes with the new parliament. After abdicating, he moved to England, where he eventually suffered a heart attack and then passed away.
A search for J. M. Wheeler turned up a link to a November 1938 ophthalmology journal that contained both an article that he wrote and an article commemorating his passing away.