The 'uncinate process' in the lateral nasal wall determines the drainage pathway of the maxillary sinus. The maxillary sinus natural ostium drains into which structure?

• A Inferior meatus under the inferior turbinate
• B Superior meatus
• C Sphenoethmoidal recess
• D Middle meatus directly via the hiatus semilunaris into the infundibulum ✓

Explanation

The maxillary sinus natural ostium opens into the ethmoidal infundibulum via the hiatus semilunaris in the middle meatus — the key drainage pathway of the ostiomeatal complex (OMC). The infundibulum is bounded medially by the uncinate process. The inferior meatus contains the nasolacrimal duct opening (Hasner's valve), not the maxillary sinus. Understanding this anatomy is the basis of functional endoscopic sinus surgery (FESS), where uncinectomy opens the natural drainage pathway.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.