Stokes suffered the injury after being struck in the face by a Durham academy player while helping in the nets in February during the English county side's pre-season training.
Durham had hoped Stokes would be fit for the start of the County Championship season that starts this week, but the allrounder's availability has been pushed back.
"(The incident) could have been horrific," Durham head coach Ryan Campbell said at the team's pre-season media day.
"So, so much worse than what you think. A couple of centimetres a different way it hits him in the eye and it could have been different.
"The ball was hit so hard. We are just lucky he got away with it."
Stokes has not played any competitive cricket since the final Ashes Test in Australia in January, s series which England lost 4-1.
Following a review of that tour, it has been decided that Stokes and England head coach Brendon McCullum will remain in their roles and Campbell has no doubt that the skipper will have a point to prove.
"He has been training so hard to be ready," Campbell said. "He has a lot to prove.
"You don't have to be a rocket scientist to know the Ashes didn't go so well and he is a proud man who wants England to be the best team in the world.
"He, as a professional, is working at getting right and ready to go."
Ollie Robinson wants to make a statement at the start of the domestic county season and wants to "knock the door down" in the hopes of being recalled to the England Test team.
England batter Ben Duckett has withdrawn from his contract with Indian Premier League side Delhi Capitals to stay at home and play domestic first-class cricket.
England captain Ben Stokes admits the last few months has been the "hardest" of his leadership journey following the aftermath of the Ashes defeat in Australia.
Despite a disappointing campaign at the ICC Men's T20 World Cup, Jos Buttler has made it clear he has no intention of stepping away from international cricket.
