Introduction: the nasal cavities are entered through the nostrils
or anterior nares. It has medial wall, lateral wall, roof and floor. The roof
is curved and narrow except at the posterior end. It is divided into three parts:
frontonasal, ethmoidal and sphenoidal. The floor is wider than the root and is
formed by the palatine process of maxilla and the horizontal plate of the
palatine bone. The medial wall is formed by the nasal septum and is usually
smooth.
Lateral wall: this is uneven due to the three longitudinal
elevations called conchea or turbinates. This elevations are called the
superior, middle and inferior nasal conchae. The superior and middle conchae
are parts of the ethmoid bone but the inferior concha is a separate bone.
The superior conchae: this is small and extend posteriorly
from its junction from the middle conchae. Its lower edge is free and overlies
the superior meatus.
The middle conchae: this is midway in size and position between
the posterior and inferior chonchae. It extends horizontally back from its
junction with the superior chonchae. It overhangs the middle meatus.
Blood supply: the nasal cavity is supplied by the
sphenopalatine artery. Veins drain the pterygoid plexus.
Lymph drainage: lymph drains to submandibular, deep cervical
and retropharyngeal nodes.
Nerve supply: branches of the trigeminal nerve.