Paranasaalisten

Paranasaalisten refers to the paranasal sinuses, a group of air-filled cavities located in the bones surrounding the nasal cavity. The principal sinuses are the maxillary sinuses (in the cheeks), the frontal sinuses (in the forehead), the ethmoidal sinuses (between the eyes), and the sphenoidal sinuses (behind the eyes). Each sinus opens into the nasal cavity through narrow passages and is lined with ciliated mucous membrane. The size and shape of these cavities vary among individuals, and some people have accessory openings or underdeveloped spaces.

The sinus cavities develop from the nasal cavities during childhood, with pneumatization continuing into adolescence. They are connected to the nasal cavity by small ostia and are lined by mucous-secreting epithelium. The mucous produced helps humidify the air and is cleared toward the nasal passages by ciliary action.

Functions attributed to the paranasal sinuses include reducing skull weight, warming and humidifying inhaled air, and enhancing voice resonance. They also provide a buffer against facial trauma and offer a mucosal surface that participates in immune defense of the nasal passages.

Clinical significance: Inflammation of the sinus mucosa, or sinusitis, is a common condition that can be acute or chronic. Causes include viral or bacterial infections, allergies, and dental infections. Symptoms typically include nasal obstruction, facial pressure or pain, reduced sense of smell, and nasal discharge. Diagnosis is usually based on history and examination, with imaging such as computed tomography (CT) or magnetic resonance imaging (MRI) used when needed. Treatment depends on the cause and may involve nasal irrigation, intranasal corticosteroids, analgesics, antibiotics for bacterial infection, and, in refractory cases, surgical drainage to restore sinus drainage.