What is "mild central interstitial prominence which appears chronic in nature"?

[schizofriendia]

I recently had to go to the ER because within seconds while laying down I felt the worst shortness of breath I've ever had in my life that lasted several minutes before it started to gradually go away. I felt like I was suffocating and came close to losing consciousness. When they did x-rays at the hospital they told me I had pneumonia, but the test results that went to my medical records app also said there was "mild central interstitial prominence which appears chronic in nature" which the doctor didn't even bring up to me. When I got back home from the hospital, the severe shortness of breath tried to occur again, but rolling on my side before it became full blown had made it stop.

What does "mild central interstitial prominence which appears chronic in nature" even mean and what could possibly cause it? I can't really find anything on Google about what that phrase could mean and it keeps sending me to pages about interstitial lung disease.