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What is Egg shell calcifiaction of the hilar nodes is seen in- and explain in detail?
Eggshell calcification is a radiographic term describing abnormal hilar or mediastinal lymph nodes. According to Fraser and Pare, "Eggshell calcification is uncommon; it consists of a ring of calcification around the periphery of a lymph node and occurs most typically in silicosis. Ref Davidson 23rd edition pg 599