Assists in the Sense of Smell
The olfactory epithelium is membranous tissue located inside thenasal cavity.
It measures about 3 square centimeters (cm2) in adults.
Containing olfactory receptor cells, it is involved in the sense of smell.
Olfactory disorders can range from a mild decrease in the ability to smell to a complete loss of smell.
A loss of smell can indicate a mild illness or injury or something more serious.
A decrease in the ability to smell can be an early indicator of Parkinsons disease and Alzheimers disease.
In adults, it is situated about 7 centimeters (cm) behind the nostrils.
It is part of the nasal septum and the superior turbinatebones.
Three cell types make up the olfactory epithelium: basal, supporting, and olfactory.
Olfactory receptor cells have hairlike extensions called cilia.
It used to be thought that the olfactory epithelium developed separately from the olfactory placode.
Anatomical Variations
The nasal epithelium can be affected by congenital conditions (those present at birth).
Another genetic disorder that can impair smell is ciliopathy.
In ciliopathy, the body’s ability to make cilia is impaired.
When cilia are not there or they are malformed, a person does not have the ability to smell.
The olfactory bulb is located in the front of thebrain.
Loss of smell is not uncommon in people withtraumatic brain injury.
Lack of smell can contribute to mood disorders, too, like anxiety and depression.
Presbyosmia is an age-related loss of smell.
It may be related to a loss of nerve endings and mucus production as people age.
An increased use of medication as well as neurological disorders also may contribute to age-related loss of smell.
Cancer of the nasal cavityis rare.
Squamous cell cancer is the most common cause of nasal and paranasal cancers, followed by adenocarcinoma.
Problems with your ability to smell can also arise.
Later stages may involve nose bleeds, facial and tooth pain, and eye problems.
Molecular genetic testing may also be performed to identify gene mutations.
Treatment for Kallmann syndrome and nIHH usually involves hormone replacement therapy.
Medication to strengthen the bones may also be used, as the absence of puberty hormones can weaken them.
Advances inDNA testing(genetic testing) using RNA sequence analysis may help diagnose ciliopathy.
Nasal endoscopy may be used to look inside your nose.
Your healthcare provider may prescribe decongestants, antihistamines, or nasal sprays for allergies.
If an infection is the cause, antibiotics may be in order.
Smoking is known to impair the ability to smell, so quitting smoking may also help.
If there is a blockage in the nasal passage, your healthcare provider may discuss surgically removing apolypor tumor.
Nasal cancer is diagnosed by an ear, nose, and throat specialist (otolaryngologist).
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2019;1862(11-12):194433. doi:10.1016/j.bbagrm.2019.194433
