Nasal Anatomy and Evaluation

Abstract

The nose is a signifi cant organ of respiration and the primary organ of olfaction. The nasal septum is a cartilaginous and bony structure that divides the nose into two chambers. The anatomy of the lateral nasal wall is formed by a series of folds and spaces known respectively as the nasal conchae and meati. The effect of these structures on the inspired air-stream sets the parameters for nasal breathing and the treatment of air before it is directed down into the lungs. The turbulent airfl ow caused by the conchae adds to the perceived resistance of nasal airfl ow and the sensation of adequate breathing. Turbulent airfl ow allows for the wafting of molecules to the sensory cells of the olfactory system and thus aids the senses of taste and smell. The paranasal sinuses, immediately adjacent to the nasal cavity, are air-fi lled spaces lined with respiratory epithelium in continuity with the epithelium of the nasal cavity. Within the confi nes of the nose and paranasal sinuses courses the collecting portion and the lower drainage portion of the lacrimal system and the lacrimal sac and duct, respectively. The complex relationship between nasal anatomy and the lacrimal system requires that the ophthalmologist has a good understanding to successfully approach the lacrimal system while avoiding complications in the nasal cavity.