You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Signet ring sign is seen in: March 2013 and explain in detail?
Ans. D i.e. Bronchiectasis Signet ring sign The signet ring sign is a CT finding seen in patients with Bronchiectasis The ring of soft-tissue attenuation represents the wall of the dilated bronchus seen on a cross-sectional CT scan, whereas the low-attenuating circle of air represents air within the dilated bronchus. The circle of soft-tissue attenuation abutting the ring represents a cross-sectional image of the pulmonary aery that lies adjacent to the dilated bronchus.