Lees missed last Friday’s 1-0 victory at Wigan Athletic after picking up a knock in the away game at Bristol City eight days ago, while Hooper - back in training - has been out of action for two-and-a-half months with a hamstring injury, with his last appearance coming in the draw at Fulham on November 19.
Definitive news sees full-back Morgan Fox back in training and available for the home game with Blues, while integral midfielder Sam Hutchinson is back in the fold following a two-match suspension.
On Lees and Hooper, head coach Carvalhal, whose side are now embarking on back-to-back home games with Blues and Blackburn, with Hillsborough staging six of the club’s next nine league fixtures, said: “We are not sure yet. We have more than 48 hours to go until the game.
“We have some doubts about Tom Lees. We are also waiting to recover Gary Hooper.
“We will know tomorrow (Thursday). if they are available or not.”
Wednesday can move five points clear of seventh-placed Norwich with victory on Friday.