One of the few dark clouds hanging over Eagles camp involves Mike Patterson.

The 29-year-old defensive tackle underwent brain surgery, to repair tangled blood vessels, in the offseason and won’t participate in practices at Lehigh. He did report Sunday with his teammates, but doctors still haven’t cleared him to play.

“Physically, I feel fine,” Patterson told reporters. “I feel like I can go out there and put the pads on and hit somebody. But doctor’s orders, so that’s what I’m going with, and hopefully everything works out.”

Patterson, who was drafted by the Eagles in 2005, had a seizure last August, when he collapsed on the practice field at Lehigh. His condition doesn’t appear to be career threatening, according to head athletic trainer Rick Burkholder. With Patterson out, coach Andy Reid said that he will use a four-man rotation at defensive tackle, including Cullen Jenkins, Antonio Dixon, Derek Landri and Fletcher Cox.

Eagles add Ogbu for D-line depth

Before the news about Patterson broke, the Eagles announced they had acquired defensive tackle Ollie Ogbu from the Indianapolis Colts in exchange for cornerback D.J. Johnson. The team also signed free agent receiver Anthony “Tiger” Jones and cornerback Kee-ayre Griffin.

Ogbu was signed as an undrafted free agent by Indianapolis in 2011. He spent last season on the Colts’ practice squad. Ogbu was a three-year starter for Penn State, where he racked up 113 tackles and 5.5 sacks as a senior.