Schwartze first described patulous eustachian tube in 1864 when he noted a scarred atrophic eardrum moving synchronously with respiration. This condition was first fully described in 1867 by Jago, who had a patulous eustachian tube
Patulous Eustachian tube, also known as patent Eustachian tube, is the name of a rare physical disorder where the Eustachian tube, which is normally closed, instead stays intermittently open. When this occurs, the patient experiences autophony, the hearing of self-generated sounds. These sounds, such as one's own breathing, voice, and heartbeat, vibrate directly onto the ear drum and can create a "bucket on the head" effect
Symptoms
Patulous Eustachian tube sounds very similar to the standard congestion one gets from a cold or allergies, though there are subtle differences. The effect is often described as "drier"; with normal congestion, breathing and talking echo in the head with a muffled sound. With patulous Eustachian tube, variations in upper airway pressure associated with respiration are transmitted to the middle ear through the eustachian tube. This causes an unpleasant fullness feeling in the middle ear and alters the auditory perception. Complaints seem to include "muffled" hearing and autophony. In addition, patulous Eustachian tube generally feels dry with no clogged feeling or sinus pressure.
Some patients with this condition are disturbed by the perceived volume of their voice, causing them to speak very quietly. Their own voice may also sound lower to other people, because the trachea has more volume when the Eustachian tube is open. The patient may also sound as if they have congestion when speaking. Some sufferers may have difficulty in normal activities. Increased breathing rate, such as that brought on by physical activity. The increased activity not only increases the rate and force of pressure changes in the airway, which is therefore transmitted more forcefully into the middle ear, but also drives increased blood flow to peripheral muscles, compounding the problem by further depleting the eustachian tube of extracellular fluid and increasing patency. The combination can lead to severe exacerbation of the symptoms. The urge to "clear" the ear is often mentioned
Diagnosis
Upon examination of a suspected case of patulous Eustachian tube, a doctor can directly view the tympanic membrane with a light and observe that it vibrates with every breath taken by the patient. A tympanogram may also help with the diagnosis. Patulous Eustachian tube is likely if brisk inspiration causes a significant pressure shift.
Patulous Eustachian tube is frequently misdiagnosed as standard congestion due to the similarity in symptoms and rarity of the disorder. Audiologists are more likely to recognize the disorder, usually with tympanometry or nasally delivered masking noise during a hearing assessment, which is highly sensitive to this condition.[1]
When misdiagnosis occurs, a decongestant medication is sometimes prescribed. This type of medication aggravates the condition, as the Eustachian tube relies on sticky fluids to keep closed and the drying effect of a decongestant would make it even more likely to remain open and cause symptoms. The misdiagnosed patient may also have tubes surgically inserted into the eardrum, which increases the risk of ear infection and will not alleviate patulous Eustachian tube. If these treatments are tried and failed, and the doctor is not aware of the actual condition, the symptoms may even be classified as psychological.
Incidentally, patients who instead suffer from the even rarer condition of superior canal dehiscence are at risk for misdiagnosis of patulous Eustachian tube due to the similar autophony in both conditions.........
Causes
Patulous Eustachian tube is a physical disorder. The exact causes may vary depending on the person. Weight loss is a commonly cited cause of the disorder due to the nature of the Eustachian tube itself. Fatty tissues hold the tube closed most of the time in healthy individuals. When circumstances cause overall body fat to diminish, the tissue surrounding the Eustachian tube shrinks and this function is disrupted.[2]
Activities and substances which dehydrate the body have the same effect and are also possible causes of patulous Eustachian tube. Examples are stimulants (including caffeine) and exercise. Exercise may have a more short-term effect than caffeine or weight loss in this regard.
Pregnancy can also be a cause of patulous Eustachian tube due to the effects of pregnancy hormones on surface tension and mucous in the respiratory system
Treatment
Historically, to temporarily alleviate symptoms, patients have tried positional maneuvers, such as tilting their head to one side or upside down, lie down on their backs, or sit in a chair with their head between their knees. Similarly, a routine of lying down four times per day with legs elevated to around 20 inches for at least two weeks has been attempted as well. Depending on the underlying cause of the disorder, the individual may need to remove caffeine from their diet, reduce exercise, or gain weight.
Estrogen (Premarin) nasal drops or saturated potassium iodide have been used to induce edema of the eustachian tube opening. Nasal medications containing diluted hydrochloric acid, chlorobutanol, and benzyl alcohol have been reported to be effective in some patients, with few side effects. Food and Drug Administration approval is still pending, however
Local Therapy to Patulous Eustachian Tube
Bezold method (Bezold,1908)
Narrow the lume of the Eustachian Tube by salicylic accid/bolic accid insufflation
Narrow the lumen ofthe Eustachian Tube by extrinsic compression
Paraffin injection (Zollner,1937), Teflon injection (Pulec,1967),Gelatine sponge injection (Ogawa,1976)
Alter the function of palatal muscles (Misurya,1974)
Pterygoid hamulotomy (Virtanen,1982),Occlusion of the bony Eustachian Tube with a tympanotomy(Bluestone,1981)
Myryngotomy and insertion of a ventilating tube (Suehs,1960)
Temporary relief
Diathermy (Robinson,1989)
Using a ureteric Diathermy probe
Patients with a patulous eustachian tube who are pregnant and those with mild symptoms (most patients) need informative reassurance alone. Patients who have symptoms during pregnancy are symptom-free after delivery.
Advise patients to do the following:
■Increase or regain lost weight
■Avoid diuretics
■Recline or lower head when symptoms occur
Topical administration (nasal preparation) with anticholinergics may be effective for some patients........
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