About the structure and physiological function of the sinuses Sinuses: located in the human skull, some air-containing cavities in the skull around the nasal cavity, generally symmetrically arranged on both sides, there are four pairs, named according to the skull in which they are located, called maxillary sinus, sieve sinus, frontal sinus and butterfly sinus (as shown in the figure), these sinuses are usually filled with air and connected to the nasal cavity by small tubes.
Maxillary sinus: Located in the maxilla below the eye, it is the largest of the four pairs of sinuses.
Sieve sinus: located between the eyes and the nose, in the sieve bone above the external nasal cavity and leading backward to the skull.
Frontal sinus: located in the frontal bone above the eye, anterior to the septal sinus.
Pterygoid sinus: located in the center of the skull at the base of the skull, within the pterygoid bone and above the last part of the nasal cavity
The physiological functions of the sinuses are still inconclusive, but it is certain that: increase the mucous membrane area of the respiratory area and the warming and humidifying effect on the inhaled air; the resonance effect on the sound; reduce the weight of the head and increase the buoyancy of the head in the water; the role of protection of vital organs; the role of heat insulation.
Therefore, when various causes of rhinitis or nasal mucosa swelling and congestion, so that the various sinus openings blocked, when these sinus openings blocked, it will affect the nasal mucus stagnation in the sinuses, affecting the drainage discharge. If not diagnosed and treated early, it can evolve into sinusitis.