Young male asymtomatic
MENISCUS SIGN: HYDATID CYST
The lung is the second most common site of involvement with echinococcosis granulosus in adults after the liver
Usually seen as a well-defined nodular lesion, single or multiple, with low attenuation cystic values on CT, with no enhancement/ sometimes wall may enhance due to inflammatory reaction around the lesion.
May reach large sizes, upto 20 cm.
Meniscus or Air Crescent sign is describes the crescent of air that can be seen in lung lesions - seen in pulmonary hydatid and pulmonary aspergllloma.