###Human: There is a hazy region near lung nodule in a CT-scan. Why? ###Assistant: Hi. I have read through the 10 images uploaded, 8 CT images and two report images (attachment removed to protect patient identity). You are right about the haziness posterior to the nodule in images 97-99/ 241. So what we see is a nodule with hazy margins. Concerning this appearance, it can be reactive changes surrounding the nodule that is slowly healing (as you mentioned a course of Doxycycline is completed and she is feeling better) or it can still mean some residual active infection in the area. Therefore we need to address the issue from a more clinical perspective than an isolated nodule. Fleishner society recommendations are followed to know if a certain nodule is of potential neoplastic etiology. It is true that you are having a stressful situation at the moment but there is no obvious finding in the report that can cause any chronic blood in the cough. The ground glass opacities are a subjective finding and many radiologists mention it where the opacities are prominent. However, I have noted that she is on Clopidogrel 75 mg and if she had a violent cough before the bleeding then it might be possible that she had a small mucosal injury in the aerodigestive tract.