The marked structure on the X-ray is:: (A) Nasopharynx, (B) Ethmoidal air cells, (C) Sphenoid sinus, (D) Pituitary gland
Answer is C. (c) Sphenoid sinus(Ref. Scott Brown, 6th ed., 4/3/2)Shown below are X-ray Waters view (occipitomental) with open mouth and X-ray Nose & PNS- lateral view. Note the highest sinus in the lateral view is the frontal sinus.