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What is Alpha Lynch Howah surgery is for and explain in detail?
External frontoethmoidectomy (Howah's or Lynch operation) - The frontal sinus is entered through its floor by a curvilinear incision round the inner margin of the orbit. Diseased mucosa is removed, ethmoid cells exenterated and a new frontonasal duct created. Ref- Dhingra, 6th edition , page 196.