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.

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 mucus in the respiratory system.

Granulomatosis with polyangiitis can also be a cause of this disorder. It is yet unknown why.

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.

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.

The most common complications of the posterior pharyngeal wall flap are hyponasality, nasal obstruction, snoring, and sleep apnea. Rarer complications include flap separation, sinusitis, postoperative bleeding, and aspiration pneumonia. Possible complications of the sphincter pharyngoplasty are snoring, nasal obstruction, difficulty blowing the nose.

Some researches suggest that sphincter pharyngoplasty introduces less hyponasality and obstructive sleep symptoms than the posterior pharyngeal wall flap. Both surgeries have a favourable effect on the function of the Eustachian tube.

The prevalence has been estimated at 1 in 10,000 births, but exact values are hard to know because some that have the symptoms rarely have Pierre-Robin sequence (without any other associated malformation).

Sphincter pharyngoplasty is mostly used for horizontal clefts of the soft palate. Two small flaps are made on the left and right side of the entrance to the nasal cavity, attached to the back of the throat. For good results, the patient must have good palatal motion, as the occlusion of the nasal cavity is mainly carried out by muscles already existing and functioning.

Children affected with PRS usually reach full development and size. However, it has been found internationally that children with PRS are often slightly below average size, raising concerns of incomplete development due to chronic hypoxia related to upper airway obstruction as well as lack of nutrition due to early feeding difficulties or the development of an oral aversion. However, the general prognosis is quite good once the initial breathing and feeding difficulties are overcome in infancy. Most PRS babies grow to lead a healthy and normal adult life.

The most important medical problems are difficulties in breathing and feeding. Affected infants very often need assistance with feeding, for example needing to stay in a lateral(on the side) or prone(on the tummy) position which helps bring the tongue forward and opens up the airway. Babies with a cleft palate will need a special cleft feeding device (such as the Haberman Feeder). Infants who are unable to take in enough calories by mouth to ensure growth may need supplementation with a nasogastric tube. This is related to the difficulty in forming a vacuum in the oral cavity related to the cleft palate, as well as to breathing difficulty related to the posterior position of the tongue. Given the breathing difficulties that some babies with PRS face, they may require more calories to grow (as working of breathing is somewhat like exercising for an infant). Infants, when moderately to severely affected, may occasionally need nasopharyngeal cannulation, or placement of a nasopharyngeal tube to bypass the airway obstruction at the base of the tongue. in some places, children are discharged home with a nasopharyngeal tube for a period of time, and parents are taught how to maintain the tube. Sometimes endotracheal intubation or tracheostomy may be indicated to overcome upper respiratory obstruction. In some centers, a tongue lip adhesion is performed to bring the tongue forward, effectively opening up the airway. Mandibular distraction can be effective by moving the jaw forward to overcome the upper airway obstruction caused by the posterior positioning of the tongue.

Given that a proportion of children with Robin sequence will have Stickler syndrome, it is important that a child with PRS have an evaluation by an optometrist or ophthalmologist in the first year of life looking for myopia that can be seen in Stickler syndrome. Because retinal detachment that can occur in Stickler syndrome is a leading cause of blindness in children, it is very important to recognize and be thoughtful of this diagnosis.

Affected Persons are infants and toddlers, who had been in need of a temporary feeding tube because of their acute medical condition. This can include extreme prematurity, chromosomal anomalies, cardiac conditions, gut anomalies demanding immediate surgery like esophageal atresia or any medical complication leaving the infant in a fragile medical condition with insufficient nutritional intake. After treatment, children often unnecessarily remain tube fed avoiding any contact with food, resist the offering, touching and tasting of food and finally become tube dependent. The affected children are unable start/resume self-directed eating behaviour of tube feeding to make the transition to oral nutrition, as they develop an active aversion to or a disinterest in food. [3]

Tube dependency develops in children who have the physical ability to ingest and digest food, but failed to be weaned off their temporary intended tube by traditional means and resist/refuse or cannot make the transition to natural oral feeding. It occurs after the phase of critical medical treatment and interventions when the child is expected to resume or start oral intake.

The medical reasons affecting oral explorative behavior, appetite, sucking and swallowing coordination are diverse, including extreme prematurity, neonatal or postnatal operations, intensive care, parenteral feeding, respiratory support and many more.

Many children are tube-fed during the critical age and the stage of developing oral skills. They may have neuromuscular and sensory conditions requiring physio-occupational and speech and language therapy before becoming ready for learning to eat.

The condition also has psychological and social causes. Children who have experienced oral trauma or have been exposed to medicines with bad flavors may become reluctant to repeat oral experiences.

Many children have been on the receiving end of well-intended encouragement and intrusive feeding attempts or even forced feeding, resulting in growing refusal and oppositional behavior. As the phenomenon of tube dependency is hardly recognized as a problem or functional disorder, there is no scientific data on the issue of incidence or risk of development nor epidemiology in countries with a high standard of neonatal medicine and surgery.

Anotia ("no ear") describes a rare congenital deformity that involves the complete absence of the pinna, the outer projected portion of the ear, and narrowing or absence of the ear canal. This contrasts with microtia, in which a small part of the pinna is present. Anotia and microtia may occur unilaterally (only one ear affected) or bilaterally (both ears affected). This deformity results in conductive hearing loss, deafness.

Individuals with Nager syndrome typically have the malformations of the auricle, external auditory canal, and middle ear, including the ossicles. These malformations were found in 80% of individuals with Nager syndrome. Inner ear malformations, however, are not typically seen in this population. Middle ear disease is common among individuals with Nager syndrome. Chronic otitis media and Eustachian tube deformity can result in conductive hearing loss. For this reason, early detection and treatment for middle ear disease is crucial in this population. Sensorineural hearing loss is not a typical characteristic of Nager syndrome; however, a subset of individuals present with a mixed hearing loss, due to a progressive sensorineural component combined with the typical conductive hearing loss (Herrman "et al.", 2005).

Some conditions that are associated with hyperacusis include:

- Acoustic shock

- Adverse drug reaction

- Anxiety

- Autism spectrum

- Lyme disease

- Migraine

- Ménière's disease

- Endolymphatic hydrops

- Multiple Sclerosis

- Noise-induced hearing loss

- Posttraumatic stress disorder

- Severe head trauma

- Superior canal dehiscence syndrome (SCDS)

- Systemic lupus erythematosus (SLE)

- Tay–Sachs disease

- Williams syndrome

"20% to 40% of children with microtia/anotia will have additional defects that could suggest a syndrome."

Treacher-Collins Syndrome: (TCS) A congenital disorder caused by a defective protein known as treacle, and is characterized by craniofacial deformities; malformed or absent ears are also seen in this syndrome. The effects may be mild, undiagnosed to severe, leading to death. Because the ear defects are much different in this disorder and not only affect the outer ear, but the middle ear as well, reconstructive surgery may not help with the child's hearing and in this case a Bone Anchored Hearing Aid would be best. BAHA will only work, however if the inner ear and nerve are intact.

Goldenhar Syndrome: A rare congenital birth defect that causes abnormalities of facial development. also known as Oculoauricular Dysplasia. The facial anomalies include underdeveloped, asymmetric half of the face. The defect is capable of affecting tissue, muscle, and the underlying bone structure of the side of the face with the abnormality.

Ablepharon-macrostomia Syndrome: (AMS) A rare genetic disorder characterized by various physical anomalies which affect the craniofacial area, the skin, the fingers, and the genitals.

The most common cause of hyperacusis is overexposure to excessively high decibel (sound pressure) levels.

Some come down with hyperacusis suddenly as a result of taking ear sensitizing drugs, Lyme disease, Ménière's disease, head injury, or surgery. Others are born with sound sensitivity, develop superior canal dehiscence syndrome, have had a history of ear infections, or come from a family that has had hearing problems.

Some psychoactive drugs such as LSD, methaqualone, or phencyclidine ("angel-dust") can cause hyperacusis. An antibiotic, ciprofloxacin has also been seen to be a cause, known as "ciprofloxacin-related hyperacusis".

Hearing loss with craniofacial syndromes is a common occurrence. Many of these multianomaly disorders involve structural malformations of the outer or middle ear, making a significant hearing loss highly likely.

Diverticula may occur in one of the three areas of the esophagus - the pharyngoesophageal, the midesophageal area or the epiphrenic area of esophagus. Zenker's diverticulum is found three times more frequently in men than in women. It occurs posteriorly through the cricopharyngeal muscle in the midline of the neck. Usually seen in people older than 60 years of age.

- Gastric diverticula - "Although usually asymptomatic, they may cause vague epigastric pain. These lesions may be confused radiologically for gastric ulcers or cancers. Endoscopically, they may be confused for paraesophageal hernias."

- Killian-Jamieson diverticulum

- Meckel's diverticulum: a persistent portion of the omphalomesenteric duct present in 2% of the population

- Rokitansky-Aschoff sinuses: in the gallbladder due to chronic cholecystitis

- Traction esophageal diverticulum: due to scarring from mediastinal or pulmonary tuberculosis

- Urethral diverticulum: congenital in males, post-infectious in females

- Zenker's diverticulum: a diverticulum of the mucosa of the pharynx affecting adults

Most of these pathological types of diverticulum are capable of harboring an enterolith. If the enterolith stays in place, it may cause no problems, but a large enterolith expelled from a diverticulum into the lumen can cause obstruction.

It was found that based on sensitized measures of auditory dysfunction and on psychological assessment, Subjects could be subdivided into seven subcategories:

1. middle ear dysfunction

2. mild cochlear pathology

3. central/medial olivocochlear efferent system (MOCS) auditory dysfunction

4. purely psychological problems

5. multiple auditory pathologies

6. combined auditory dysfunction and psychological problems

7. unknown

Different subgroups may represent different pathogenic and aetiological factors. Thus, subcategorization provides further understanding of the basis of King–Kopetzky syndrome, and hence may guide the rehabilitative management of these patients.This was suggested by Professor Dafydd Stephens and F Zhao at the Welsh Hearing Institute, Cardiff University.

It seems that somatic anxiety and situations of stress may be determinants of speech-hearing disability.

Some studies indicated an increased prevalence of a family history of hearing impairment in these patients. The pattern of results is suggestive that King-Kopetzky patients may be related to conditions of autosomal dominant inheritance.

Universal Newborn Hearing Screenings (UNHS) is mandated in a majority of the United States. Auditory neuropathy is sometimes difficult to catch right away, even with these precautions in place. Parental suspicion of a hearing loss is a trustworthy screening tool for hearing loss, too; if it is suspected, that is sufficient reason to seek a hearing evaluation from an audiologist.

In most parts of Australia, hearing screening via AABR testing is mandated, meaning that essentially all congenital (i.e., not those related to later onset degenerative disorders) auditory neuropathy cases should be diagnosed at birth.

Known causes include physical trauma, acoustic neuroma, measles, labyrinthitis, microtia, meningitis, Ménière's disease, Waardenburg syndrome, mumps (epidemic parotitis), and mastoiditis.

A diverticulum (plural: "diverticula") is the medical or biological term for an outpouching of a hollow (or a fluid-filled) structure in the body. Depending upon which layers of the structure are involved, they are described as being either true or false.

In medicine, the term usually implies the structure is not normally present. However, in the embryonic stage, some normal structures begin development as a diverticulum arising from another structure.

A 1998 study of schoolchildren found that per thousand, 6-12 had some form of unilateral hearing loss and 0-5 had moderate to profound unilateral hearing loss. It was estimated that in 1998 some 391,000 school-aged children in the United States had unilateral hearing loss.

There are several factors that may not be harmful to the auditory system by themselves, but when paired with an extended noise exposure duration have been shown to increase the risk of auditory fatigue. This is important because humans will remove themselves from a noisy environment if it passes their pain threshold. However, when paired with other factors that may not physically recognizable as damaging, TTS may be greater even with less noise exposure. One such factor is physical exercise. Although this is generally good for the body, combined noise exposure during highly physical activities was shown to produce a greater TTS than just the noise exposure alone. This could be related to the amount of ROS being produced by the excessive vibrations further increasing the metabolic activity required, which is already increased during physical exercise. However, a person can decrease their susceptibility to TTS by improving their cardiovascular fitness overall.

Heat exposure is another risk factor. As blood temperature rises, TTS increases when paired with high-frequency noise exposure. It is hypothesized that hair cells for high-frequency transduction require a greater oxygen supply than others, and the two simultaneous metabolic processes can deplete any oxygen reserves of the cochlea. In this case, the auditory system undergoes temporary changes caused by a decrease in the oxygen tension of the cochlear endolymph that leads to vasoconstriction of the local vessels. Further research could be done to see if this is a reason for the increased TTS during physical exercise that is during continued noise-exposure as well.

Another factor that may not show signs of being harmful is the current workload of a person. Exposure to noise greater than 95 dB in individuals with heavy workloads was shown to cause severe TTS. In addition, the workload was a driving factor in the amount of recovery time required to return threshold levels to their baselines.

There are some factors that are known to directly affect the auditory system. Contact with ototoxic chemicals such as styrene, toluene and carbon disulfide heighten the risk of auditory damages. Those individuals in work environments are more likely to experience the noise and chemical combination that can increase the likelihood of auditory fatigue. Individually, styrene is known to cause structural damages of the cochlea without actually interfering with functional capabilities. This explains the synergistic interaction between noise and styrene because the cochlea will be increasingly damaged with the excessive vibrations of the noise plus the damage caused by the chemical itself. Specifically, noise damage typically damages the first layer of the outer hair cells. The combined effects of styrene and noise exposure shows damages to all three rows instead, reinforcing previous results. Also, the combined effects of these chemicals and the noise produce greater auditory fatigue than when an individual is exposed to one factor immediately followed by the next.

It is important to understand that noise exposure itself is the main influential factor in threshold shifts and auditory fatigue, but that individuals may be at greater risk when synergistic effects take place during interactions with the above factors.

There have not been sufficient studies conducted to make conclusive statements about prevalence nor who tends to suffer EHS. One study found that 13.5% of a sample of undergrads reported at least one episode over the course of their lives, with higher rates in those also suffering from sleep paralysis.

The disorder can be associated with a number of psychological symptoms, anxiety, depression, social phobia, body image disorders, and patients may be subjected to discrimination, bullying and name calling especially when young. A multi-disciplinary team and parental support should include these issues.

Although auditory fatigue and NIHL protective measures would be helpful for those who are constantly exposed to long and loud noises, current research is limited due to the negative associations with the substances. Furosemide is used in congestive heart failure treatments because of its diuretic properties. Salicylic acid is a compound most frequently used in anti-acne washes, but is also an anticoagulant. Further uses of these substances would need to be personalized to the individual and only under close monitoring. Antioxidants do not have these negative effects and therefore are the most commonly researched substance for the purpose of protecting against auditory fatigue. However, at this time there has been no marketed application. In addition, no synergistic relationships between the drugs on the degree of reduction of auditory fatigue have been discovered at this time.