<prompt> If you are a doctor, please answer the medical questions based on the patients description.what does this mean.. RIGHT pulmonary nodule: Crescentic pulmonary nodule within the RIGHT mid lung zone corresponding to the abnormality on chest radiograph. This is of uncertain etiology and is not characteristic for a granuloma, small pulmonary nodule, or most mass lesions. There do appear to be several small vessels associated with the limbs of this crescentic lesion, and a pulmonary AVM is a consideration  <response>: Thanks for your question on Chat Doctor. I can understand your situation and problem. There are many causes of concentric pulmonary nodule. But the common ones are1. Pulmonary AV arteriovenous Malformations.2. Fungal ballaspergilli3. Developing lung abscess4. Benign cyst.5. Less likely due to tuberculosis or malignant mass. So get done CT thorax and bronchoscopic evaluation of the lesion. CT is far better than chest x-ray for lung parenchymal lesion. Bronchoscopy will give you naked eye appearance of lesion. So both are needed to establish the diagnosis. So consult pulmonologist and discuss these possible causes. 