Introduction: The location of the natural ostium of the sphenoid sinus in the surgical field has been
variably reported according to different standard points. However because of severer pathological
changes, massive polyps in nasal cavities and altered anatomic reference points, revision endoscopic sinus
surgery often challenges surgeon`s skill and experience. Through our endoscopic sinus surgeries, we
noticed a constant relationship between middle meatal antrostomy and site of sphenoid face.
Objectives: To establish a novel approach to sphenoid sinus using middle meatal antrostomy as landmark
in difficult cases of endoscopic sinus surgery with lost landmarks or revision ones. Study design: A
prospective study
Patients and methods: Fifteen patients (6 males, 9 females) with mean age of 37.7 ys, have been
operated with endoscopic sinus surgery for different pathologies, after finishing middle meatal
antrostomy and sphenoidotomy, we drew an imaginary line between point at most postero-inferior margin
of antrostomy (flush with posterior wall of maxillary sinus) directed superio-medially to posterior part of
septum and touching superior limit of sphenoid face.
Results: On the images recorded after operation, we measured the angle between this line and horizontal,
and found that to range from 40-45º, with a mean of 41.5º, this line had a mean length of 17.1 mm,
anterior wall of sphenoid was always below this line.
Conclusion: A reference point on middle meatal antrostomy can be used as constant landmark to identify
face of sphenoid sinus; this is mostly helpful in difficult cases of endoscopic sinus surgery.