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ENT Knowledge Base



Eustachian Tube Dysfunction


Eustachian tube is a structure connecting the nasopharynx and middle ear cavity. Normally it is closed but it opens when we swallow or yawn. It serves to equalize the middle ear air pressure to the outside. Moreover during diving, elevating or landing of flight, there is also change of pressure. If the tube does not work, the pressure in the ear will be different to that outside. Thus affecting our hearing. It is known to be a predisposing factor to infection of the middle ear.

Diagnosis & Treatment:

What are the symptoms of eustachian tube dysfunction?

They are:

  • ear blockage

  • hearing one's own voice (autophony)

  • intermittent ear discomfort

  • tinnitus ( ringing)

What can cause eustachian tube dysfunction?
Common causes are:

  • allergic rhinitis i.e. hay fever

  • upper respiratory infection

  • adenoid enlargement

  • nasopharyngeal cancer including the primary disease and post-radiotherapy

  • drugs: such as oral contraceptive pills

  • hormonal change

  • significant weight loss

  • stress and fatigue

  • congenital cleft palate

How to treat eustachian tube dysfunction?

  • Perform microscopic examination of ear to rule out middle ear infection with fluid.

  • Perform nasoendoscopy to exclude rhinosinusitis and nasopharyngeal cancer.

  • impedance tympanometry and eustachian tube function test

  • drugs to enhance the opening of eustachian tube

If severe, may need trial of grommet insertion.


Diagram showing the Eustachian Tube



During diving and flight elevation or landing, the pressure is changing To adapt to it, pressure of middle ear should be changed accordingly by opening up the eustachian tube. Besides swallowing or chewing action, sometimes Valsava maneuver may be needed. However if the eustachian tube function is impaired or the change of depth or height level is too fast, pressure of middle ear cavity cannot be equalized and barotrauma may result. It may injury the ear drum resulting in perforation, middle ear cavity mucosa resulting in bleeding and fluid collection, even the inner ear through the round window causing severe sensorineural hearing loss./p>

Diagnosis & Treatment:

How to diagnose barotrauma?

  • history of recent flight or diving would be hint for diagnosis.

  • Otoscopic or microscopic examination of the eardrum would show blood or fluid inside the middle ear cavity.  Sometimes perforation of ear drum may occur

  • Pure tone audiogram is necessary as it usually shows conductive hearing loss.  However if inner ear is involved, sensorineural hearing loss may be seen.

How to treat barotrauma?

  • For ear drum perforation, observation is suggested.  If it is not healed up after 3 months eventually, repair by surgical operation is recommended

  • For blood or fluid in the middle ear, observation is suggested.  But it can be drained by myringotomy if it is not subsided after a period of time.

If there is inner ear injury, conservative management such as bed rest and drugs is recommended.  But if hearing deteriorates progressively, surgical exploration and operation would be suggested.


Barotrauma with Blood in Middle Ear Cavity

Acute Otitis Media


Acute otitis media is acute infection of the middle ear which is either due to viral or bacterial infection. It happens in children more commonly because of immature and short eustachian tube. The pathogen is usually entering the middle ear through the tube so it is associated with common cold, flu and cough.


All ear pain in children is due to middle ear infection?

No. Both AOM and acute infection of external ear canal (otitis externa) commonly occur in children. Therefore it is important to differentiate them as the treatment is different.

Diagnosis & Treatment:

Is treatment different between otitis media and otitis externa?

Yes. For otitis externa (ear canal infection), ear toilet, topical antibiotic eardrops with or without oral antibiotic is the standard treatment. For AOM, topical ear drop is not helpful. Oral antibiotics, oral antihistamine and nasal decongestant are the usual treatments. In case of possibility of development of complication or severe ear pain, a small cut on the ear drum may be needed to relieve the symptoms and drain the pus.

What are the symptoms of AOM?

The classic presentations are:

  1. high fever

  2. severe ear pain

  3. symptoms of rhinitis (running nose)

  4. mild impairment of hearing because of fluid in middle ear

  5. If ear drum is ruptured, ear discharge occurs

How to distinguish between otitis media and otitis external?

It is difficult to distinguish the two without examination of ear canal and ear drum. In AOM, ear drum is red and bulging. The external ear canal is usually dry unless ear drum is ruptured. In otitis externa, pus is usually present in the ear canal. The canal is painful when it is touched. Concurrent symptoms of upper respiratory infection such as cold and flu are usually associated with AOM but not OE.

Is hearing affected after AOM?

After AOM, some fluid may accumulate in the middle ear resulting in conductive hearing loss. This usually resolves with treatment within 4-6 weeks of time. If it is not resolved after a period of time, a small cut on the ear drum with or without tube insertion may be needed.


Acute Otitis Media

Otitis Media with Effusion


It is a very common condition in children. It usually follows acute middle ear infection or cold and flu. Sometimes in those cases of hay fever, they may suffer from this condition. It can be straw-colored fluid or glue-like material in the middle ear. It would cause conductive hearing loss. Therefore in the paediatric population, if they suffer from bilateral OME, we would tend to treat it more aggressively with a small cut on ear drum and tubes insertion. Otherwise hearing loss may affect their language and cognitive development. In adult, OME can be due to post-barotraumas or after upper respiratory tract infection like cold and flu. However, it is important to bear in mind that nasopharyngeal cancer is one of significant disease causing unilateral OME, especially for us who live in Southeast China where NPC (Nasopharyngeal cancer) is much more common than any other places in the world. So almost it is recommended that nasoendoscope should be performed to all adult who suffer from unilateral OME.


Fluid in middle ear is always needed to be drained. No. Except paediatric cases with bilateral OME and hearing impairment, we may observe for any resolution of OME with time. Short-term antibiotic may be tried as it is the only evidence-based useful drug for OME resolution. Antihistamine or nasal corticosteroid spray may be used but there is no strong evidence of their effect

Diagnosis & Treatment:

How is fluid in middle ear treated?

Regain of normal function of eustachian tube is the key to success. Short-term antibiotic, antihistamine and nasal steroid may be used. If OME persists, a small cut on the ear drum and tube insertion should be considered.


Otitis media with Effusion

Chronic Suppurative Otitis Media


It usually presents as chronic perforation of ear drum with episodic ear discharge. It can be due to previous poorly treated AOM (acute middle ear infection) or poor eustachian tube function. Because of improved hygiene and earlier use of antibiotic in AOM (acute middle ear infection) cases, the incidence of CSOM is decreasing in the recent years.


Repair of ear drum in CSOM can reduce symptom of tinnitus (ringing of ear)? Not necessarily. In CSOM, ear ossicle and inner ear may be affected. These may be the cause of ringing sound in ear. Therefore even if ear drum is repaired, there may still be some residual ringing sound. As ringing sound is a symptom which may be caused by a lot of different factors, it is difficult to guarantee that it is totally treated by any means.

Ear drum perforation should always be repaired.

It depends on the age, daily activity (e.g. want to swim again) and desire of the patient. Besides, it is necessary to ensure that there is no active infection of the operated ear and the hearing of the opposite ear. So the decision is tailor-made by both patient and the ENT surgeon by considering all the factors together.

Diagnosis & Treatment:

Why are some people prone to develop CSOM (chronic middle ear infection with discharge)?

While the majority of eardrum perforation heals spontaneously, some perforations persist due to unresolved infection or Eustachian tube dysfunction.


What are the symptoms of CSOM?

  1. hearing loss

  2. ear discharge

  3. sometimes tinnitus(ringing sound in ear), dizziness/vertigo

What is cholesteatoma?

Cholesteatoma may be classified as a form of chronic suppurative otitis media, i.e. middle ear infection with discharge. However, it is different from the usual CSOM that skin "grows" inside the middle ear and mastoid process and forms a "tumor-like" plague. If it is not treated and removed, it will invade into the surrounding structure such as inner ear, facial nerve, brain resulting into total deafness, severe dizziness, facial nerve paralysis, intracranial infection such as meniningitis and brain abscess. Mastoidectomy would be the standard treatment so as to remove the disease and expand the mastoid cavity.

How to treat CSOM?

  1. ear toilet under microscope when ear is discharging

  2. topical antibiotic eardrop application

  3. Eardrum Repair (Tympanoplasty)

Is repair of eardrum perforation always successful?

In general, the success rate of Eardrum Repair (Tympanoplasty) would be around 80%. However there are factors affecting its success rate including size of perforation and any concomitant upper respiratory infection at the peri-operative period.


Chronic Suppurative Otitis Media

CSOM-1 (1).jpg

CSOM with Dry Central Perforation

Ear Drum Peforation


Normally the middle ear and external ear canal is separated by the thin membrane called tympanic membrane or ear drum. If it is perforated, bacteria or fungus can enter into the middle ear causing ear discharge.

Diagnosis & Treatment:

What are the symptoms of perforated ear drum?

  1. may have no symptom if not infected and the perforation is small

  2. hearing loss

  3. tinnitus (ringing sound in ear)

What causes perforated ear drum?

  1. CSOM (Chronic Suppurative Otitis Media)

  2. trauma

  3. diving

  4. explosion

CSOM (1).jpg

Traumatic Perforation of Ear Drum


Eardrum Repair (Tympanoplasty)



It is different from the usual CSOM (chronic suppurative otitis media) that skin "grows" inside the middle ear and mastoid process and forms a "tumour-like" plague. If it is not treated and removed, it will invade into the surrounding structure such as inner ear, facial nerve, brain resulting into total deafness, severe dizziness, facial nerve paralysis, intracranial infection such as meniningitis and brain abscess. Mastoidectomy would be the standard treatment so as to remove the disease and exteriorize the mastoid cavity

Diagnosis & Treatment:

Diagnosis of cholesteatoma:

  • examination under microscope

  • CT scan of temporal bone

Treatment for cholesteatoma:

  • ear toilet under microscope

  • topical antibiotic eardrop

  • mastoidectomy





Vestibular Neuronitis


The vestibular organ (for sense of balance) may be affected by various viral agents resulting in the condition called vestibular neuronitis

Diagnosis & Treatment:

What is the presentation of vestibular neuronitis?

It is usually presented as sudden onset of sustained vertigo and dys-equilibrium accompanied by a spontaneous wobbling of eyeballs lasting from 3 to 7 days followed by gradual resolution.

Does it affect the hearing?

No. As it only affects the vestibular nerve, the auditory nerve is spared and patient usually has normal hearing. So if hearing is impaired at the same time, it would be a case of SSNHL ( sudden Sensorineural hearing loss) rather than simple vestibular neuronitis. Those patients should be treated accordingly.

Does it recur?

As it is an acute insult by virus on the vestibular nerve, it does not tend to recur. However if there is recurrent infection, it may result in recurrence of such vertigo episodes. For recurrent dizziness, it is much more likely to be Meniere's disease rather than vestibular neuronitis.

What is treatment of vestibular neuronitis?

Basically it only needs supportive treatment with relief of dizziness during the acute episode. Vestibular sedative can be used temporarily.

Diagnosis & Treatment:

What is presentation of BPPV (Benign Paroxysmal Positional Vertigo)?

The patient with BPPV (Benign Paroxysmal Positional Vertigo) experiences severe spinning associated with a change of head position. The most frequently cited occurrence of this symptom follows rolling over in bed or getting into bed and assuming a lying-on-back position. Patients are often awakened from sleep with dizziness when they roll over. Frequently, a specific side is volunteered, e.g., "the dizziness comes when I roll over to my right side but not to the left."

What test can be done when BPPV (Benign Paroxysmal Positional Vertigo) is suspected?

A test called Dix-Hallipike maneuver is done for eliciting nystamus (wobbling of eyeballs) and vertigo caused by posterior canal BPPV. The patient's head is first turned 45 degree to the right. His/her neck and shoulders are then brought into the supine position with the neck extended below the level of the examination table. The patient is observed for nystamus or complaints of vertigo. The patient is next returned to the upright position.

Does it recur?

As it is an acute insult by virus on the vestibular nerve, it does not tend to recur. However if there is recurrent infection, it may result in recurrence of such vertigo episodes. For recurrent dizziness, it is much more likely to be Meniere's disease rather than vestibular neuronitis.

Is BPPV (Benign Paroxysmal Positional Vertigo) treatable?

Yes. It can be treated by Epley repositioning maneuver for posterior canal BPPV. It can be done by a trained personnel only for example, the ENT specialist.


Diagram showing the Vestibular Nerve which is affected in Vestibular Neuronitis


BPPV theory (Benign Paroxysmal Positional Vertigo)

Benign Paroxysmal Positional Vertigo

In general, the theory of canalithiasis, which is well accepted as the explanation of BPPV (Benign Paroxysmal Positional Vertigo)? When we turn or move our head or change our positions, the stone-like substances in the ampulla ( the organ for sense of balance)moves and irritate the said organ. Thus, giving us spinning sense i.e. vertigo).

Acoustic Neuroma


It is a condition where a benign tumor is arising from the eighth cranial nerve which is called vestibulocochlear nerve (mostly involves the vestibular nerve rather than the cochlear nerve). It usually affects one side only. In a familial condition called neurofibromatosis type II, both sided eighth cranial nerve would be involved.

Diagnosis & Treatment:

What is the presentation of acoustic neuroma?

The classic presentation of acoustic neuroma would be unilateral progressive sensorineural hearing loss. Dizziness may be the symptom but it does not necessarily exist because the vestibular function would be impaired slowly and progressively while the brain can usually have enough time to compensate. If the tumor is enlarged to an extent that brain is compressed, central nervous system symptoms may exist. MRI scanning is the gold standard for diagnosis of acoustic neuroma.

How can Acoustic Neuroma be treated?

When acoustic neuroma is diagnosed, we need to consider how to manage the tumor. If the tumor is small, we would prefer to observe it with regular MRI scanning. Sometimes for the elderly, we may not consider too aggressive treatment for them as the tumor is slow growing when comparing with the life expectance of the elderly. But when the tumor grows to significant size, we need to seriously consider further management. We can choose to have surgical removal but the operation is an ultra-major one with potential serious operation morbidity. There are several approaches and patient can discuss with the surgeon on them. Besides, gamma knife is an alternative option but not a curative method in selected c



It is a hereditary localized disease of the bone derived from the otic capsule. It affects ladies more at the age between 20-50 years. It can involve either one or both ears. Conductive deafness will be resulted although it can result in mixed hearing loss.

Diagnosis & Treatment:

How can we diagnose otosclerosis?

Clinically the ear drum is normal in appearance. With pure tone audiogram, we can identify a conductive hearing loss with occasional sensorineural component. The definitive diagnosis can only be made with tympanotomy (surgical access to the middle ear cavity and checking of mobility of the ossicles). If the stapes, the ear ossicle attaching to the inner ear (oval window), is immobile with abnormal new bone formation, it would be otosclerosis.

What is the treatment of otosclerosis?

We can either treat it with hearing aids or operative treatment which is called stapedectomy. It consists of removal of part of stapes, drilling a hole over the oval window and insertion of new prosthesis connecting the incus and the inner ear which acts as a replacement for the original stapes function.


MRI scanning showing acoustic neuroma


Pathology of otosclerosis

Skin Lesion of Pinna


It can be benign or malignant lesion. For malignant ones (i.e. cancer), the usual causes are sun exposure and it usually happened in elderly more often.

Diagnosis & Treatment:

How to diagnosis skin lesions of the pinna?

Direct inspection without biopsy is applied. Normally, the lesions are removed by excision and the specimen is then checked by pathologist.

What is the treatment?

Excision is the usual option. But for the sake of doubt, excision is better than observation.

Tumor of Ear


Tumor can arise from the external ear canal, middle ear part and the auditory nerve. Radical excision of tumor is advised in case of cancer whenever it is feasible.

Pictures showing the glomus tumor of ear (a type of ear tumor)

Diagnosis & Treatment:

How can we diagnosis the tumor?

Direct inspection is applied under the aide of otoscope. CT scan and MRI scan are other diagnostic stools. Biopsy is used to confirm the type of tumor but not in case of vascular tumor e.g. glomus tumor.

How to treat the tumor?

Different tumors require different approach. It depends on the judgment and the experience of the surgeon to tailor-make a specific regime of individual cases.


glomus tumour


glomus tumour


glomus tumour

Meniere's Disease


This disease is first described in 1861 by Dr. Meniere with a series of similarly afflicted patients. It is characterized by recurrent episodes of vertigo (dizziness), hearing loss and tinnitus (ringing sound in ear) of sudden onset. The principal pathological feature of this disease is called endolymphatic hydrops which means increased volume of endolymph (fluid in middle ear) in inner ear structure called scala media. Whenever hydrops occurs, episode of vertigo would happen

Diagnosis & Treatment:

Should we classify all recurrent vertigo or dizziness to be Meniere's disease?

No. Actually it is too arbitrary to say all dizziness case to be Meniere's disease. One of the most important criteria to define Meniere's disease should be recurrence. If it is only the first or sole attack, we cannot classify it to be Meniere's disease. Secondly, we need to clarify on the classical presentation. For the vertigo attack, it should last at least half an hour to a day. It is easy to remember the rule of 24-24, that is 24 minutes to 24 hours. Moreover it would be associated with aural fullness, transient unilateral hearing loss and tinnitus (ringing sound in ears) during the episode. Usually it is subsided afterwards. Some of cases may even have permanent Sensorineural hearing loss after recurrent attacks.

Can we find the cause of Meniere's disease?

Usually we cannot find any causes. However in some of cases with similar presentation, we can identify a cause, e.g. syphilis, CSOM( chronic suppurative otitis media) , trauma. The pathology in these is endolymphatic hydrops. But it would be better to define them as secondary endolymphatic hydrops rather than Meniere's disease.

How can we treat Meniere's disease?

During acute attack, vestibular sedative would be helpful to relieve symptom. Besides, there are several different drugs sr that may be helpful in some cases. Surgery such as endolympatic sac decompression (major operation) would be the last resort but its effectiveness is still uncertain. Besides surgery, chemical ablation of vestibular end organ is another option. Regardless of any treatment, most of cases will eventually have less severe and less frequent attacks.


Diagram showing endolympatic hydrops which is basis of Meniere’s disease

Sudden Senorineural Hearing Loss


Sudden Sensorineural hearing loss is a common ENT condition. It almost always affects one side only. "Sudden" by definition means a few hours to 3 days. But most of these cases present within one day. It is often preceded by minor upper respiratory infection such as flu and cold though it is not necessarily present. Therefore some of the authorities assume that viral infection of inner ear may be an important cause of SSNHL. Another hypothesis is that it may be due to impairment of local circulation of inner ear and the vestibulocochlea nerve. Besides hearing loss, some patients may suffer from severe dizziness or vertigo and tinnitus (ringing sound in ear)

Diagnosis & Treatment:

Can we often identify the cause of SSNHL?

No. Actually we can seldom identify the exact cause of the SSNHL(Sudden Sensorineural hearing loss) However we can perform tests to rule out important or treatable causes such as high blood cholesterol, diabetic and acoustic neuroma (tumour of auditory nerve).

What is the treatment for SSNHL without obvious cause?

Systemic steroid is the evidence based treatment of choice as it can suppress the inflammation caused by the viral infection. Vasodilator is another option although it has less evidence for its effectiveness. Recent studies show that intra-tympanic steroid may be used in those cases not responding to the conventional treatment. Besides, hyperbaric oxygen is evidence based useful treatment.

Is it possible to have acoustic neuroma (tumor of the auditory nerve) causing SSNHL?

Yes. However acoustic neuroma usually presents as progressive SNHL (progressive sensorineural hearing loss) rather than the sudden type. For those present as SSNHL (Sudden Sensorineural hearing loss), it is assumed that the tumor is expanding to an extent that it just compresses on the blood supply to inner ear and the auditory nerve. Though there is low possibility of Acoustic neuroma (tumor of the auditory tumor), those who have SSNHL, we still suggest those who do not respond to treatment to have MRI scanning so as to rule out Acoustic neuroma (tumor of the auditory tumor).

Who would have less chance of recovery?

There are few factors which do not favour the recovery. They are advanced age, vertigo/dizziness, elevated ESR (a blood result) and poor hearing assessment result at presentation.

hearing-loss-pure-tone-audiometry (2).jp
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