Alpha Lynch Howah surgery is for
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.
Nasal septal perforation
Chronic frontal sinusitis
Acoustic neuroma
Otosclerosis
Diagnostic and operative ENT