Coach Jason Garrett, who never specifically addressed the lung puncture, said Monday that he did not rule out Romo playing next week against Washington, and sources confirmed that it doesn't change his status for that game.
"I would not think there's any reason to think that he won't play Monday," Garrett said. "We're certainly hopeful."
The Cowboys sent out a release later Monday that said Romo has evidence of a pneumothorax, which is a collection of air or gas in the space around the lungs. It can be the result of a puncture caused by trauma such as a rib fracture.
A source said the puncture was "very small."
Romo said Sunday that because he was able to close out the game against the Niners, he would play against the Redskins on Monday Night Football. In the locker room Monday, Romo said the pain was the same as it was after the game.
The team was unable to get a clean X-ray during Sunday's game at San Francisco's Candlestick Park, which required the CT scan.
Romo suffered the injury when Niners linebacker Ahmad Brooks hit him on a 25-yard completion to tight end Jason Witten on the game's third play. Romo managed to get through the first half but missed all but 37 seconds of the third quarter as the medical staff waited for pain-killing medicine to take effect.
Romo returned and led the Cowboys to the comeback win by completing 12-of-15 passes for 201 yards in the fourth quarter and overtime. He connected with Jesse Holley on a 77-yard completion in overtime to set up Dan Bailey's game-winning field goal.
Romo will receive extra treatment and could wear extra protection for his ribs.
Romo would not be the first Cowboys' quarterback to play with a punctured lung. Don Meredith threw for 406 yards in a 31-30 win at Washington on Nov. 13, 1966. Meredith completed 4-of-5 passes for 64 yards and ran for six yards to set up Danny Villanueva's game-winning 20-yard field goal in the final minute.
Baltimore Colts Hall of Famer Johnny Unitas and former Houston Oiler Dan Pastorini also played with punctured lungs.
In 2001, New England's Drew Bledsoe was knocked out of the game against the New York Jets with a punctured lung, which developed into a life-threatening situation. That led to Tom Brady's ascension the starter's job.
In other injury news, sources said running back Felix Jones suffered a dislocated shoulder on Sunday but was able to continue to play with a harness. He should be available to play against the Redskins. Center Phil Costa (knee) and Witten (ribs) also checked out OK.
According to sources, wide receiver Miles Austin is not expected to play against the Redskins after aggravating a hamstring injury he suffered during training camp. While it is possible he could play Oct. 2 against Detroit, the more likely return date is Oct. 16 at New England after the bye week.
Todd Archer and Ed Werder cover the Cowboys for ESPNDallas.com.