Bolshoi Ballet artistic director Sergei Filin says he knows in his heart who was behind the recent acid attack on him, but has declined to name a suspect.

The former dancer-turned-ballet chief checked out of a Moscow hospital on Monday, accompanied by his wife, Maria. His face red, swollen and slightly scarred from acid burns, Filin wore a bandage wrapped around his head, a hat and dark glasses shielding his eyes, which were also burned in the shocking assault.

On Jan. 17, a masked assailant approached as he returned home after work and threw sulphuric acid at his face before running off. It was about 20 minutes before Filin was able to flag down a security guard and seek help.

Sergei Filin, seen in Moscow with Bolshoi dancers in 2011, was a former principal dancer at the esteemed Russian company. (Mikhail Metzel/Associated Press)

On Monday, the 42-year-old Filin seemed upbeat as he briefly spoke to reporters before leaving for Germany, where he will continue his rehabilitation going forward.

"My body is full of strength and energy," he told media gathered at the hospital.

However, he noted that his eyesight has not yet fully returned and that he would require further surgery in Germany. He has already undergone five operations since the attack.

Filin added that he has been in nearly daily contact with acting Bolshoi artistic director Galina Stepanenko, whom he called "wonderful."

'My heart knows who did it'

In interviews with Russian and British media that aired Sunday, Filin said he knew who had ordered the assault on him.

"I fell on my face in the snow and began to rub snow in my face and eyes...I was in terrible, unbearable pain," Filin told a Russian TV network.

"My heart knows who did it and, in my soul, I have an answer to that question."

He did not reveal any names, but said he hopes investigators would announce the identity of the perpetrator soon.

"I don't care about my face, my hair, my looks," he said in the interview with Rossiya 24 TV.

"I'm ready to be completely bald, look like a Frankenstein. It will have no impact on my heart, on my soul. All my inner self, all my energy is focused on recovering eyesight."

Filin, a former Bolshoi principal dancer, stepped into the top post in March 2011. He said his personal email and social media accounts were hacked and he began receiving threats several weeks before the acid attack.

Though hailed on the international stage, the venerable Bolshoi has been mired in intrigue, infighting and rivalries, with the key post of artistic director changing frequently over the past 15 years. Speaking to media, Filin and others have surmised that the attack against him was a comment against his leadership of and the direction he is taking the esteemed Russian troupe.

In addition to the attack on Filin, the Bolshoi has made headlines worldwide recently for prima ballerina Svetlana Lunkina's decision to move to Canada — temporarily, for now — after receiving threats tied to a feud between her husband and a former business partner.

With files from The Associated Press