A CT scan performed before endoscopic sinus surgery shows an air cell located along the inferomedial floor of the orbit, adjacent to the maxillary sinus roof. The surgeon is warned that this cell may be mistaken for the floor of the orbit during dissection. Which anatomical variant is described?

• A Agger nasi cell
• B Concha bullosa
• C Onodi cell
• D Haller cell ✓

Explanation

The Haller cell (infraorbital ethmoid cell) pneumatizes into the orbital floor along the roof of the maxillary sinus and can narrow the maxillary ostium or mimic the true orbital floor, risking orbital entry if mistaken for it. The agger nasi cell lies anterior to the frontal recess, the Onodi cell lies posterolateral to the sphenoid near the optic nerve, and a concha bullosa is a pneumatized middle turbinate.

Reference: Cummings Otolaryngology: Head and Neck Surgery, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.