Paranasal sinuses are air-filled cavities located in the bones surrounding your nose.
According to medical definitions, paranasal sinuses are one of many small hollow spaces in the bones around the nose. These spaces are interconnected and lined with the same mucous membranes found in the nose.
Location and Names
The paranasal sinuses are named after the specific bones in the skull that contain them. There are four main pairs of these sinuses.
The reference states: "Paranasal sinuses are named after the bones that contain them: frontal (the lower forehead), maxillary (cheekbones), ethmoid (beside the upper nose), and sphenoid (behind the nose)."
Here's a breakdown of each type and its location:
| Sinus Name | Location Based on Bone | Approximate Area |
|---|---|---|
| Frontal | Frontal bone | Lower forehead, above eyes |
| Maxillary | Maxillary bones | Cheekbones, below eyes |
| Ethmoid | Ethmoid bone | Beside the upper nose, between the eyes |
| Sphenoid | Sphenoid bone | Behind the nose and below the brain |
Key Characteristics
- Hollow Spaces: They are empty cavities, reducing the weight of the skull.
- Located Around the Nose: Positioned symmetrically on either side of the nose.
- Lined with Mucosa: Covered by a layer of tissue similar to the lining of the nasal cavity, which produces mucus.
- Connected to the Nasal Cavity: Small openings (ostia) connect the sinuses to the nasal passages, allowing for air exchange and mucus drainage.
Understanding the paranasal sinuses involves recognizing their specific locations within the facial bones. These cavities are integral components of the respiratory system's upper airway structure.
Learn more about sinus anatomy and function.
