Egg cell calcification is characteristic of -

Ans. is 'b' i.e., Silicosis o Irregular central calcification (Popcorn calcification) is characteristic of hamartoma.Calcification patterns on chest radiography1) Egg-shell calcification of lymph nodes :- It is defined as shell-like calcifications up to 2 mm thick in periphery of at least two lymph nodes in at least one of which, the ring of calcification must be complete and one of the affected Ivmph nodes must be at least 1 cm in maximum diameter, important causes are :-y Silicosis (m.c. cause)y Coal worker's pneumoconiosisy Sarcoidosisy Lymphoma following radiationy Blastomycosisy Histoplasmosisy Sclerodermay Amyloidosisy Progressive massive fibrosis (PMF)y Coccidiodomycosisy TuberculosisIrregular central popcorn calcification It is a cluster of sharply defined irregularly lobulated calcification usually in a pulmonary nodule. It is characteristic of hamartoma.Laminated or central pattern Granuloma.Punctate pattern :- Tuberculoma or coccidiodomycosis.