Brown was replaced after an hour of Tuesday's 2-1 defeat against Benfica which leaves the Hoops needing to better the Portuguese side's result against Barcelona on December 5.
Reports after the match in Lisbon claimed the skipper could be facing up to 10 weeks on the sidelines but Lennon is looking for one final effort from Brown before he goes under the knife.
The midfielder has been used sporadically this season due to the injury but could be set for a shock recall in Saturday's home fixture against Inverness.
"Scott is in contention to play on Saturday remarkably. We will refer him to a specialist after Moscow and see how he is then," said Lennon.
"The problem is we don't have time to let him settle down. Looking at the condition, it normally requires surgery. On Tuesday he was just out of condition a bit because he has not trained.
"Obviously we would like him feeling completely free going into these games and that's why we are upping his condition work a bit to see if we can get him peaking for the Moscow game if we can.
"We are not making the condition any worse, the only problem is it's not getting any better. The medical team feel surgery will fix the problem, and when we do it is coming closer."