Turbinates, also known as nasal conchae, are long, narrow, curled bony structures that protrude into the nasal cavity. They are covered by mucosa and play a crucial role in filtering, humidifying, and warming inspired air. There are typically three pairs of turbinates—superior, middle, and inferior—with a fourth, the supreme turbinate, present in some individuals.
Each turbinate consists of a bony core covered by highly vascularized mucosa. They form ridges along the lateral walls of the nasal cavity and are arranged in a stacked configuration:
Turbinates are located along the lateral walls of the nasal cavity. Each turbinate overhangs a corresponding passageway called a meatus:
These meatuses serve as drainage pathways for the paranasal sinuses and nasolacrimal duct.
Turbinates are vital for normal nasal physiology. Their functions include:
The mucosal covering of turbinates is lined with **pseudostratified columnar epithelium with cilia and goblet cells**. Beneath this epithelium lies a submucosal layer rich in seromucous glands and venous sinusoids that contribute to the warming and humidification functions.
Turbinates are closely associated with sinus drainage:
Turbinates are highly vascular and receive blood from:
Sensory innervation is provided by branches of the trigeminal nerve (CN V), particularly the ophthalmic (V1) and maxillary (V2) divisions:
Autonomic fibers from the pterygopalatine ganglion modulate glandular secretion and vascular tone.
Chronic inflammation from allergies or infections can cause the turbinates, especially the inferior ones, to enlarge, resulting in nasal obstruction, congestion, and mouth breathing.
In allergic rhinitis, the turbinates become swollen due to histamine-mediated vasodilation, leading to nasal congestion, sneezing, and rhinorrhea.
Turbinate reduction (e.g., inferior turbinate reduction) may be performed in cases of persistent nasal obstruction unresponsive to medical therapy. Care is taken to preserve mucosal function.
This rare condition occurs after excessive turbinate removal, leading to paradoxical nasal obstruction and dryness despite wide nasal passages.
Turbinates develop from the lateral wall of the nasal cavity during embryogenesis. The inferior turbinate forms as a separate ossification center, while the middle and superior turbinates originate from the ethmoid bone primordium.
CT scans of the paranasal sinuses provide detailed visualization of the turbinates and their relationship to the sinuses. MRI can assess mucosal thickening or soft tissue abnormalities.