Three American eye specialists who were summoned by the Soviet government to Moscow last Friday performed an operation on a senior Soviet leader Sunday, well-informed sources here said.

The sources refused to identify the man except to say that he is a member of the ruling Politburo. The only member of the 13-man body to have eye problems is Mikhail Suslov, the top ideologist.

The presence in Moscow of a Johns Hopkins University Hospital team coincided with speculation that Soviet President Leonid Brezhnev was gravely ill.

Speculation earlier yesterday in Western Europe that the Soviet leader had died was reinforced by an Agence France-Presse dispatch from Brussels reporting that Soviet television had canceled its regular evening news broadcast. Such cancellation are normally a prelude to major announcements.

However, the agency subsequently amended its report by saying that there was a last-minute cancellation by the Soviets of a special feed from the Kremlin for other European television companies. The Soviet television news was broadcast on schedule.

Moscow was quiet last night and there was no unusual activity detectable either in the Kremlin or in the apartment building on Kutuzovsky prospect where Brezhnev has lived for many years. A top Communist Party official dismissed the report, and today's edition of Pravda, the authoritative Soviet paper, made no mention of any Brezhnev's health problems.

State Department spokesman Hodding Carter, asked about rumors of Brezhnev's death, said, "We have checked with Moscow and have not information that would substantiate these reports."

The rumors have been circulating since Brezhnev failed to attend two scheduled meetings and a banquet in Moscow with visiting Syrian President Hafez Assad earlier this week. Syrian sources told reporters that the Soviet leader was ill.

There were no indications that Brezhnev might be suffering from an eye ailment. The three U.S. doctors in Moscow reportedly refused to tell U.S. officials the identity of their patient, arguing that their medical ethics prevents them from disclosing such information.

The doctors are Ronald Michaels, Thomas Rice and Walter Stark, all well-known specialists in the treatment of disorders of the cornea, vitreous and retina of the eye at Johns Hopkins Wilmer Eye Institute in Baltimore. a

They were invited by the Soviet Embassy in Washington to fly to Moscow for "consultation and possible treatment" of a Soviet patient, according to a hospital spokesman, Elaine Freeman.

Freeman would not provide the date the Soviet Embassy issued the invitation, but it was understood that the three doctors were contacted within the last 10 days. They departed for Moscow last Friday.

In the 1960's another Johns Hospital physician, A.McGehee Harvey, was summoned to Moscow to treat the late Soviet leader Nikita Krushchev.

Brezhnev, 72, was last seen 10 days ago in East Berlin where he was on state visit.