Conversation: The conversation between human and AI assistant.
[|Human|] I had a bout of bilateral pneumonia which still had not cleared on third xray although I seemed to have recovered otherwise. However a faint nodular opacity was found on third xray in left lung base. A CAT scan has been ordered, but I am very worried. Is it possible it could be something not too serious? I need to have some hope to hold on to.
[|AI|]  Thanks for your question on Chat Doctor. Nodular opacity on chest x-ray can be due to many causes. The common causes are1. Nodular pneumonia (round pneumonia)2. Benign cyst3. Developing cavitary lesion.4. Developing lung abscess5. Malignant nodule.  Etc. So CT THORAX with contrast is needed for further evaluation. CT scan is far better imaging modality than chest x-ray. This will also helpful in guided biopsy if necessary. So get done CT THORAX as soon as possible.