Olfactory part of nasal mucosa

The olfactory part of mucosa covers the apical region of each nasal cavity in an inverted U-shaped fashion:

• Superiorly, it underlines the roof of nasal cavity including the cribriform plate of ethmoid bone.

• Laterally, it covers the superior concha and part of middle concha, where it merges with the respiratory epithelium.

• Medially, it covers the sphenoethmoidal recess and the upper part of perpendicular plate of ethmoid bone (the nasal septum).

 The epithelium of olfactory part of mucosa is pseudostratified in nature. It contains a variety of cells including:

• Biploar olfactory receptor neurons.

• Sustentacular cells with microvilli. These are columnar cells and support the interspersed olfactory receptor neurons

• Basal cells.

The epithelium rests on the lamina propria that contains:

• Bowman’s olfactory glands that produce serous secretions, which cover over the olfactory mucosa.

• Axons of olfactory neurons that traverse through the cribriform plate of ethmoid bone (in the roof of nasal cavity) to meet the olfactory bulb.