The former Real Madrid man, who scored in Inter's 3-1 first-leg win, came off at halftime in the 3-1 Serie A victory over Atalanta which sent Jose Mourinho's side top on Saturday.
"Wesley Sneijder has undergone a medical check-up which showed a muscle tweak in his left thigh," Inter said in a statement.
"The condition of the Dutch midfielder will be monitored in the next 48 hours."
The possible absence of Sneijder on Wednesday would be a big blow for Inter given he has been one of their most consistent players this season and expertly links midfield and attack.
Forward Goran Pandev and right back Maicon were not risked for the Atalanta game because of muscle tightness and a broken tooth respectively but are in line to be fit for the Barca game.
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