Conversation: The conversation between human and AI assistant.
[|Human|] I had chest x-rays done back in February , at my local er , and was diagnosed with a viral infection, however I was told to have a followup cat scan done because of intrestial markings in the upper lobes of lungs, I just had the cat done this past week, what are they looking for?
[|AI|]  Thanks for your question on Chat Doctor. In my opinion they want to rule out any infection present or not in your upper lobes. Usually bilateral upper lobe lesions are seen in infection either present or past infection. And CT SCAN gives much better evaluation of lung infiltration then chest x-ray. Besides infection other causes for bilateral upper lobe reticular pattern are1. Sarcoidosis2. Sillicosis3. OLD (interstitial lung disease) rarely. So CT THORAX is must rule out all these.