After undergoing ankle surgery in February, the midfielder spent a lengthy spell on the sidelines, missing 16 games in all competitions.
Bissouma was back in action last week when he came on as a 62nd-minute substitute as Spurs suffered a 2-1 loss at Aston Villa.
"I think when players train and they train fully then in my eyes they're fit to play. We've got some decisions to make," Ryan told reporters ahead of Saturday's game against Brentford.
Spurs are seventh in the standings with 57 points, one behind sixth-placed Brighton & Hove Albion, who have a game in hand.
Mason's side will look to bounce from their loss to Villa and qualify for the Europa League after missing out on a top-four finish.
Mason said Spurs want to give back positive energy to their fans when they host ninth-placed Brentford.
"They see and feel a team that's trying to transfer energy to them. We want to give them something to feel happy about," Ryan said.
When asked if he is ready to take up the managerial role permanently, Mason said: "I feel ready to help this club in this moment, and I absolutely do. I trust my team and the people at the club.
"Of course those decisions are club decisions but I remain confident in who I am and who my coaching team are as people. I feel I have a good connection with this club and the players and we can make an impact in a short space of time."