Noted your history and understood the concerns.Smoking
causes lung tissues to change as well as many pollutants now present in air at home, office, all over. These can damage the lung and the damaged lung is seen as a scar in the lung in CT scan
of the chest.
Since your Pulmonary function tests are normal, you can run 1200 meters easily without any problems, there is nothing to worry about at the moment.And the best part is that you have stopped smoking.
I would advise you the following in such a situation:
Go for lung physiotherapy
Avoid people with viral infection, crowded and polluted places.
Avoid all allergens and pollutants as much as possible.
Multivitamins,, mineral and other antioxidants
help to recover well.
Repeat CT scan of chest after one year to see for the progress.
Hope I have answered your query. Let me know if I can assist you further.
Dr. T Chandrakant, ENT & General Surgeon