In the ostiomeatal complex (OMC), which of the following components is MOST critical as the 'final common pathway' for maxillary, anterior ethmoidal, and frontal sinus drainage?

• A Middle meatus
• B Hiatus semilunaris
• C Uncinate process
• D Infundibulum ✓

Explanation

The ethmoidal infundibulum is the critical bottleneck — a three-dimensional cleft bounded medially by the uncinate process, laterally by the lamina papyracea, and into which the maxillary sinus, anterior ethmoidal cells, and (when the uncinate attaches to the lamina papyracea rather than middle turbinate) the frontal recess drain. Obstruction of the infundibulum is the primary pathogenetic event in chronic maxillary and anterior ethmoidal sinusitis. The hiatus semilunaris is the two-dimensional opening of the infundibulum into the middle meatus.

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.