Types

Understanding Your Sinuses

Choose a preferred language

Your sinuses are air-filled spaces between the bones in your head. They have small openings that connect to the nasal cavity. The sinuses make mucus that drains into the nose. This helps keep the nose moist and free of dust and germs.


Parts of the nasal cavity

  • The septum is the wall of cartilage and bone in the center of the nasal cavity.

  • The middle meatus is the intersection between the sinuses.

  • Turbinates are ridges on the sides of the nasal cavity.

    Front view of face showing sinuses.Side view of head showing sinuses.


Cilia keep sinuses clear

Cells with cilia and mucus on top. Arrows show mucus being swept along.

Air circulates freely though healthy sinuses. Tiny, hairlike structures called cilia line the sinuses. Cilia move the thin, watery mucus through the sinuses and into the nose. Sinuses are healthy when they drain freely. Sinus drainage can be blocked if the sinus lining is swollen or if mucus is too thick. Cilia that are damaged or don’t work correctly can also lead to problems with drainage.

Online Medical Reviewer: Ashutosh Kacker MD

Online Medical Reviewer: Daphne Pierce-Smith RN MSN CCRC

Online Medical Reviewer: Marianne Fraser MSN RN

Date Last Reviewed: 08/01/2023

© 2000-2025 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
doctor icon

Find the right provider to meet your needs

From primary care to specialty services and more.

Find a Doctor
appointment clock icon

Call for an Appointment

Offering personalized care at more than 20 clinics across three cities and two states.

Call Now
Related Articles
Read article
Ear, Nose, and Throat
Nose Fracture, No X-Ray

Based on your exam today, you have a broken bone, or fracture, of the nose. Some fractures are obvious and an X-ray is not needed. A nose fracture will cause pain, swelling, nasal stuffiness, and sometimes bleeding from the nose.

Read article
Ear, Nose, and Throat
Peritonsillar Abscess

An abscess around the tonsils can cause severe sore throat, pain with swallowing, fever, drooling, and trouble opening the mouth.

Read article
Ear, Nose, and Throat
Ear Barotrauma

Ear barotrauma is a problem of the middle ear and eardrum. It occurs when unequal pressures form inside the middle ear and outside the eardrum. This often happens with altitude changes, such as during an airplane flight or scuba diving.

Read article
Ear, Nose, and Throat
Understanding Sinus Problems

Sinus problems can cause uncomfortable symptoms. Read on to learn about how sinuses can get blocked and what the symptoms are.