The middle turbinate presents as a downward projection of the ethmoidal bone with the lateral wall adjacent to the osteum of the maxillary sinus. The middle turbinate is covered by ciliated epithelium and features minimal venous pools. Practically speaking, it has little control of airflow through the nose as secretion of mucus is the middle turbinate’s primary function. Chronic sinusitis and accompanying headaches are associated with hypertrophy or malposition of the middle turbinate.
Covered by ciliated epithelium, the inferior turbinate has many venous lakes and because of its erectile capacity, it can change mass quickly; thereby, functioning as a valve to control air volume. The inferior turbinate plays a major role in maintaining proper intranasal resistance.
The inferior turbinate is sensitive and responds to a wide range of environmental stimulants, such as smoke, air pollution, and rapid temperature changes through arti ficial climate control. These irritants are important when seen in light of the fact that turbinate tissue responds to stimu lation through the process of hypertrophy. It ceases functioning normally when the turbinate obstructs the nasal passage and this obstruction leads to chronic hypertrophy. This condition, in turn, leads to hyperplasia and subsequently to polypoid degeneration. This downward spiral of events can be interrupted by a partial resection of turbinates.
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Aug
A description of the physiology of the nose would not be complete without men tion of the turbinates: the primary air-conditioning structures of the nose.
There are three pairs of turbinates: superior, middle, and inferior and on occasion, there appears a fourth—the supreme. The superior turbinate is eth moidal in origin and is marked by a cover of pseudo-stratified ciliated columnar epi thelium. It has scant evidence of mucous glands and no evidence of venous pools and found just below the cribriform plate. Because of their small size and location, the superior and supreme turbi nates generally do not contribute to nasal obstruction.
