Wayne Boss was struck in the right eye by what is believed to be burning fireworks fragments while seeing in the new year in Dunedin's Octagon.
Since the accident, Mr Boss has undergone one operation, and had expected to undergo two more, until his prognosis changed for the worse on Tuesday.
''The consultants said 'you are probably looking at several operations in the next nine to 12 months','' Mr Boss said.
His eye was still too damaged for doctors to get a clear look, but scans showed his pupil had been split in three and his lens pushed to the back of his eye by the force of the debris.
Despite being released from hospital on Tuesday, there was still a real chance he could lose the sight in his eye permanently, he said.
''It could collapse at any stage and if it does, we are in trouble really - we've lost it.''
At present it was more comfortable to keep both eyes shut.
''I've been in a fair few bike crashes with broken bones.
''I'd rather one of them, that's all I can say.''
He expected to undergo his second operation in the middle of the month.
A Worksafe spokesman said an investigation into the accident would attempt to establish if
any laws had been broken, what caused the incident and what lessons could be learned.
It was impossible to put a timeframe on how long the investigation would take, he said.
Dunedin City Council spokesman Graham McKerracher said it was too early to tell whether the accident would influence how Chinese New Year celebrations on January 28 were run.
''We haven't made any decisions; we are just looking at what we can do.''
Mr McKerracher did not rule out the possibility the event would be celebrated without fireworks.
