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What is Direction of Nasolacrimal duct is: and explain in detail?
Nasolacrimal duct is q membranous passage which begins at the lower end of the lacrimal sac. It runs downward,backward and laterally and opens in the inferior meatus of the nose. A fold of mucous membrane called the valve of Hasner forms an imperfect value at the lower end of the duct. Ref: Dhingra 6/e,135.