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What is Normal hilar shadow in X-ray chest is produced by all except - and explain in detail?
"The lower lobe veins do not cross the hill and, therefore, do not contribute to hilar shadow".

Hilar shadow is formed by pulmonary arteries (predominant), upper lobe pulmonary veins (2nd major). Lobar bronchi, bronchopulmonary lymph nodes and a small amount of fat contribute little to the overall hilar shadow.