A patient with carcinoma of the right maxillary sinus develops numbness over the right cheek and upper lip. This finding indicates tumour erosion through which structure?
- A Posterior wall of the maxillary sinus
- B Orbital floor at the infraorbital groove and canal ✓
- C Medial wall at the middle meatus
- D Roof of the sinus at the fovea ethmoidalis
Correct answer: B. Orbital floor at the infraorbital groove and canal
Explanation
The infraorbital nerve travels in the roof of the maxillary sinus within the infraorbital groove and canal before emerging onto the face. Anaesthesia or paraesthesia over the cheek, upper lip, and lateral nose signifies destruction of this bony canal by tumour and implies involvement of the superoanterior wall near the orbit. Posterior wall extension instead causes trigeminal pain and trismus, while medial wall disease causes nasal obstruction and epistaxis.
Reference: Cummings Otolaryngology: Head and Neck Surgery, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.