Aung San Suu Kyi's personal physician, Tin Myo Win, said that for ethical reasons he could not provide the specifics of the surgery, but he described it as "semi-urgent."
He had earlier said the operation was gynecological in nature. Today, after a conversation with reporters in the Burmese capital, he was quoted by one news organization as saying the matter was "related to" a gynecological matter.
Tin Myo Win said the democracy campaigner was walking around and recovering satisfactorily in Rangoon's privately-run Asia Royal hospital, where she was taken earlier in the week. Diplomats in Rangoon call the newly-built hospital the best in the country.
The doctor says the operation has cleared up everything, and says the 58-year-old democracy campaigner is completely free of cancer. It is not clear if checking for cancer was the main purpose of the operation.
Aung San Suu Kyi has been detained by the military government in a secret location since May 30, when her political convoy was attacked by a pro-government mob in northern Burma. She has been allowed almost no visitors.
Burma has been under intense international pressure to release her, and to restart stalled talks with her political party, the National League for Democracy, or NLD.
The military government, officially called the State Peace and Development Council, has said it intends to hold "free and fair" elections, but has refused to say whether Aung San Suu Kyi or the NLD will be involved. It has also refused to give a date for her release.
Analysts have said the SPDC, as the government is also known, may not want to appear to have given in to international pressure. Sunai Phasuk, of the Bangkok-based human rights group Asia Forum, says the surgery may now provide the SPDC with a face-saving way to release Aung San Suu Kyi from detention.
Mr. Sunai Phasuk said,"Her medical treatment, her surgery, is perhaps a kind of face-saving exit for the SPDC to transfer her into a house arrest without being put into a position that they [have] given into international pressure."
The NLD won elections in 1990, but was not allowed to take power, and Aung San Suu Kyi has spent much of the time since then under house arrest. Sunai Phasuk says the detentions have taken a toll on her health.
"Well, it is clear that Aung San Suu Kyi is, that she's aging and she has been suffering for too long, but despite that she is continuing to stay on in Burma to fight together side by side with her people," Mr. Sunai Phasuk added.
Burma has been ruled by military governments for more than 40 years. The country's repressive policies and human rights abuses have led it to be subjected to economic sanctions by a number of nations.