Anatomy of the nose and sinuses
The nose
The nose is the organ of smell located in the middle of the face. The internal part of the nose lies above the roof of the mouth. The nose consists of:
- External meatus - triangular-shaped projection in the center of the face
- External nostrils - two chambers divided by the septum
- Septum - made up primarily of cartilage and bone and covered by mucous membranes. The cartilage also gives shape and support to the outer part of the nose.
- Nasal passages - passages that are lined with mucous membranes and tiny hairs (cilia) that help to filter the air.
- Sinuses - four pairs of air-filled cavities, also lined with mucous membranes.
The sinuses
The sinuses are cavities, or air-filled pockets, near the nasal passage. As in the nasal passage, the sinuses are lined with mucous membranes. There are different types of sinuses:
- Ethmoid sinus - located inside the face, around the area of the bridge of the nose. This sinus is present at birth, and continues to grow.
- Maxillary sinus - located inside the face, around the area of the cheeks. This sinus is also present at birth, and continues to grow.
- Frontal sinus - located inside the face, in the area of the forehead. This sinus does not develop until around 7 years of age.