Space
Nasal cavity
Paired chambers for breathing and smell
High-yield
Drainage map: nasolacrimal duct to the inferior meatus; frontal, maxillary and anterior ethmoidal pathways to the middle meatus; posterior ethmoidal cells to the superior meatus; sphenoid sinus to the sphenoethmoidal recess.
Overview
The septum divides the nasal interior into right and left passages. Each extends from a nostril to a posterior choana. Vascular, ciliated mucosa conditions incoming air, while a smaller olfactory region near the roof detects odors. Conchae shape the lateral wall and overhang drainage passages.
Reference facts
- Boundaries
- A bony roof includes the ethmoid cribriform plate and sphenoid; the hard palate forms the floor. The septum is medial and the conchae project from the lateral wall.
- Contents
- Conchae, meatuses and sphenoethmoidal recess; olfactory mucosa occupies parts of the roof, upper septum and superior concha.
- Communications
- Nostrils, choanae, sinus openings and nasolacrimal duct. Separate bony foramina transmit nerves and vessels; they are not normal open air passages to the cranial cavity.
- Blood supply
- Branches of the maxillary, ophthalmic and facial arteries form an interconnected mucosal supply.
- Innervation
- Olfaction: CN I. General sensation: V1 anterior ethmoidal territory and V2 nasal and palatine branches, with some regional overlap.
Clinical correlation
Anterior septal bleeding is common. Important posterior bleeds usually involve arterial branches, especially the sphenopalatine artery; Woodruff's plexus is not a sufficient explanation for all posterior epistaxis. A skull-base defect can allow cerebrospinal fluid leakage into the nose.
Frequently asked questions
What are the boundaries of the nasal cavity?
A bony roof includes the ethmoid cribriform plate and sphenoid; the hard palate forms the floor. The septum is medial and the conchae project from the lateral wall.
What does the nasal cavity contain?
Conchae, meatuses and sphenoethmoidal recess; olfactory mucosa occupies parts of the roof, upper septum and superior concha.
What does the nasal cavity communicate with?
Nostrils, choanae, sinus openings and nasolacrimal duct. Separate bony foramina transmit nerves and vessels; they are not normal open air passages to the cranial cavity.