Ophthalmologists on Wednesday successfully performed a second operation on Sergei Filin, the Bolshoi Theater's art director who recently suffered an acid attack, Interfax reported.

Russia's main ophthalmologist took part in the operation, an innovative procedure that involved the application of embryonic cells, the report said.

The ballet director is currently in stable condition, and doctors say the results of his treatment so far are encouraging.

Doctors say Filin will need about six months to fully recover. He received third-degree burns to his face and eyes on Jan. 18 when an unknown assailant threw acid in his face.

In an interview with Komsomolskaya Pravda on Tuesday, Filin said he blamed himself for thoughtlessness after turning down the theater's offer to provide him with guards and an escort after he repeatedly received threats. He said he should have gone to the media sooner to provide a full account of the threats.

The theater has found a temporary replacement to cover his position while he recovers.