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What is In FESS surgery structure preserved is? and explain in detail?
ANSWER: (C) Maxillary sinusREF: Textbook Of Oral And Maxillofacial Surgery (full Colour) 2nd edition by Neelima Anil Malik Page 583TYPES OF FUNCTIONAL ENDOSCOPIC SINUS SURGERY:Type 1Nasal endoscopy and uncinectomy with or without agger nasi cell exenteration.Type 2Nasal endoscopy, uncinectomy, bulla ethmoidectomy, removal of sinus lateralis mucous membrane and exposure of frontal recess/ frontal sinusType 3Type 2 plus maxillary sinus antrostomy through the natural sinus ostiumType 4Type 3 plus complete posterior ethmoidectomyType 5Type 4 plus sphenoidectomy & stripping of mucous membrane