Into which sinus does the maxillary sinus drain?

Into which sinus does the maxillary sinus drain?

• A. Frontal sinus
• B. Sphenoid sinus
• C. Ethmoid sinus
• D. Maxillary sinus

Answer: (D)

Drainage from a paranasal sinus follows a specific ostial path into the nasal cavity. The maxillary sinus empties its mucus through the maxillary ostium into the middle nasal meatus. That connection is what links the sinus to drainage pathways in the nose, and problems here are a common source of sinusitis because the ostium can become obstructed. Among the options, the sinus that corresponds to this drainage route is the maxillary sinus itself, since its secretions are what drain into the middle meatus via the ostium. (Frontal and ethmoid sinuses also drain into the middle meatus, while the sphenoid drains into the sphenoethmoidal recess, not into the middle meatus.)

Drainage from a paranasal sinus follows a specific ostial path into the nasal cavity. The maxillary sinus empties its mucus through the maxillary ostium into the middle nasal meatus. That connection is what links the sinus to drainage pathways in the nose, and problems here are a common source of sinusitis because the ostium can become obstructed.

Among the options, the sinus that corresponds to this drainage route is the maxillary sinus itself, since its secretions are what drain into the middle meatus via the ostium. (Frontal and ethmoid sinuses also drain into the middle meatus, while the sphenoid drains into the sphenoethmoidal recess, not into the middle meatus.)