Advanced Rhinology

Nose & Sinus

The visible part of the nose consists of bone, cartilage, and soft tissue covered with skin, with its shape and size varying widely among individuals and ethnic groups. The nasal cavity is a hollow space behind the nose that extends from the nostrils to the back of the throat (nasopharynx).

It is divided into two halves (right and left) by the nasal septum, which is made of cartilage and bone. The cavity itself is lined with mucous membrane that contains blood vessels, nerve endings, and mucus-producing glands. Located at the roof of the cavity is the olfactory region which contains specialised nerve endings responsible for the sense of smell (olfaction).

The nasal vestibule is the most anterior part of the nasal cavity, just inside the nostrils and is lined with skin containing hairs (vibrissae) that help filter large particles from the air. There are three pairs of nasal conchae or turbinates (superior, middle, and inferior) on each side of the nasal cavity. These bony structures covered with mucous membrane help increase the surface area of the nasal cavity and humidify, warm, and filter the air as it passes through.

There are four pairs of paranasal sinuses located around the nasal cavity: frontal, ethmoid, sphenoid, and maxillary sinuses. These air-filled cavities are lined with mucous membrane and connected to the nasal cavity through small openings called ostia. Sinuses are not fully developed at birth and continue to grow throughout childhood and adolescence. Like the nose, there can be significant variation in the size and shape of sinuses among individuals.

The functions of the sinuses include lightening the weight of the skull, providing resonance for the voice and a buffer against facial trauma; and producing mucus that moisturizes the nasal cavity and traps particles.