Which sinus drains into the nasal cavity through the middle meatus?

The maxillary sinus is the sinus that drains into the nasal cavity through the middle meatus. This anatomical relationship is significant because the middle meatus is a key drainage pathway for several sinuses. Specifically, the maxillary sinus opens into this region through a narrow aperture, which is located near the superior aspect of the meatus.

This drainage system is essential for proper sinus function and ventilation, as well as for maintaining the health of the nasal cavity. Disturbances or blockages in this drainage pathway can lead to sinusitis or other sinus-related issues.

In contrast, the frontal sinus drains into the nasal cavity through the frontonasal duct, which opens into the middle meatus but is not directly considered part of the maxillary sinus drainage. The ethmoidal sinuses also drain into the middle meatus but are a separate group of sinuses. Lastly, the sphenoidal sinus drains into the nasal cavity through the sphenoethmoidal recess, which is located above the superior concha and not through the middle meatus.

Understanding these drainage patterns is crucial for diagnosing and treating sinus conditions effectively.