How can a chest x-ray show that im a smoker? my doctor asked me if i smoke after looking at my chest x-ray. is there something different about a smokers x-rays and a non-smokers x-rays?

The : The classic finding on a smoker's chest film is increased lung volume, which in turn is caused by breakdown of lung tissue. The diameter of the chest is increaed, which is best seen on a view from the side, and the diaphragm is pushed down and flattened. Often, one can actually see holes in the lungs called bullae.

Yes: If someone has been smoking a long time and/or heavily, there are changes in the interstitial markings (all the little white specks in an xray) that are typical, and are sometimes referred to "dirty" lungs, where there are no specific lesions, but a pattern of mild inflammatory changes that have a distinctive look.

Dirty lungs?: Usually smoking appears on chest radiograph as prominent central markings which can also be seen in viral infection, reactive airway disease, and inhaling polutants.Interstitial markings or small lines in lungs more prominent.