The Italian won five caps in his career, scoring a try in a test against South Africa in 2001 as well as appearing in the 2003 Rugby World Cup.
But after only nine league appearances last year Benatti's retirement will come as a big blow to Aironi's RaboDirect Pro12 ambitions.
"Everything started with a routine screening to evaluate my myopia. During that check the doctor founded a cleft retinal degenerating into a partial retinal detachment, the problem persists so I decided to call it a career," he said.
"The biggest regret is that I always wanted to be able to decide when to quit the game, but unfortunately the injury has forced me to take this decision.
"I always wanted to play rugby, but only at 16 did I start to wear contact lenses and that allowed me to play rugby.
"I've collected a lot of memories in the past 16 years: my debut with Viadana in A2 against Rieti at 17, the Italian championship in 2002, the International debut for Italy against Fiji in 2001 and the try against South Africa.
"I must thank too many people for these incredible 16 years in rugby. What I want to say to the guys in the Aironi team is to stay close together, to be a solid group ready to face any difficult time they can face during the season. I will be at Zaffanella stadium to support them."
Aironi Director of Rugby Franco Tonni said: "I'm really sorry a player of his calibre is forced to quit from rugby due to such a sneaky injury.
"I remember Andrea making his debut for Rugby Viadana more than fifteen years ago. After so many years dedicated to rugby, in name of Aironi Rugby I want to thank Andrea for his professionalism.
"I'm sure as he was a successful player on the pitch, he will be a successful person in the real life."