@vic83- There is no reason to apologize.

The most prevalent indications for CT, such as COPD, interstitial lung disease, pulmonary nodule, small or large airway disease, and lung cancer screening, do not require the use of any contrast media. But if your doctors are concerned about a potential problem or are following a lesion's growth contrast is used. There doesn't seem to be a standard between hospitals about this, nor about how the CT machines are adjusted. Major teaching hospitals set standards but often local hospitals don't have enough money or trained people to make these decisions.

A group of doctors can seem like a group of doctors. Right?