The violent attack on Filin outside his home in January this year shocked fans of the legendary ballet troupe, revealing bitter infighting at the theatre. Filin suffered skin burns but the acid caused the greatest damage to his eyes and he has undergone 22 operations.
A Bolshoi soloist, Pavel Dmitrichenko, has been charged with ordering the attack by an unemployed ex-convict, although he said in court that he only wanted Filin to be beaten up.
Filin, 42, a former star dancer at the Bolshoi before he joined the management, said he would undergo further operations while in Moscow, but that he hoped to be able to work.
Despite his positive spin, he said that his treatment was not being as successful as hoped and he could still only make out light and shadows.
"This treatment will take a very long time," he said.
The report came as the theatre's new general director Vladimir Urin visited Filin at a clinic in Germany where he is being treated.
Urin was appointed last month after the sacking of the troubled theatre's previous general director Anatoly Iksanov.
The Bolshoi ballet is currently performing at a three week residency in London's Royal Opera House to generally positive reviews.
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