AC Milan midfielder Gennaro Gattuso has insisted he will not hang up his boots despite being diagnosed with a career-threatening eye complaint that has kept him sidelined since the opening match of the season.

The 33-year-old has not played since being substituted during the first half of Milan's 2-2 draw with S.S. Lazio on 9 September, after colliding with team-mate Alessandro Nesta. "That was not the cause of my problem, but it was an incident that helped me discover I had one," Gattuso told a media conference in Milan on Monday. "The 20 minutes I played against Lazio were a nightmare. I felt drunk. I could see Zlatan Ibrahimović in four different positions. Unfortunately, I always listen to that voice telling me to keep going. I was lucky to have good reason to stop after I ran into Nesta."

Gattuso has been diagnosed with sixth nerve palsy, a disorder associated with the dysfunction of the cranial nerve that controls eye movement and which is difficult to treat. "In 25% of cases the palsy of the sixth optic nerve occurs for unknown reasons," explained Milan's chief medical officer Rodolfo Tavana. "Sometimes it's a cancer or a stroke but we had two different scans from different specialists and both excluded those possibilities. Often this kind of problem clears up by itself in a period of two to six months."

FIFA World Cup winner Gattuso – whose nickname 'Ringhio' means growl in Italian – joined Milan in 1999 and has won the UEFA Champions League twice with the Rossoneri among myriad other trophies. If the last few weeks have been a worrying time, the former Rangers FC man at least believes he is now on the road to recovery. "For a while I was seriously scared about my health and worried for my life," he admitted. "But now I have undergone several tests I'm calmer and can start thinking about football.

"Football is my life – I'm a lucky man. Three weeks ago doctors told me there was a chance I might never play again, but now they are saying that is not the case and I will fight hard to return. I can train physically but I cannot play because I can't see well enough. I feel an important part of the dressing room here, I feel respected after playing here for so long. My team-mates know I'm full of enthusiasm, so age is certainly not a problem. As long as the enthusiasm is there, I can keep playing."

In Gattuso's absence, Milan have made a slow start in Serie A, lying seventh after seven matches, though the Rossoneri top UEFA Champions League Group H with seven points from three outings.