Waldayer's ring a learning resource

You can go to this link to make use of the learning resource "Waldayer's ring"

http://drtbalu.appspot.com/

Online journal of otolaryngology JORL Volume 2 Issue 2

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ENT Scholar Volume 1

ENT Scholar volume 1

Infections of Waldayer's ring an open educational resource

Infections of "Waldayer's ring" is the commonly taught topic in undergraduate Medical curriculum. This topic is not only exhaustively dealt with but also used to evaluate the students during their university examinations. This open tutorial discusses this topic thread bare. It is interactive ed and has been designed in such a way that it encourages self learning. You can view the complete tutorial here.

online journal of otolaryngology jorl volume 2 issue 1

Nasal polyposis in a child

Tuning fork tests

Introduction:

These tests are performed in order to subjectively assess a person’s hearing acuity.  This test can in fact be performed by using tuning forks of the following frequencies (254 Hz, 512 Hz, and 1024 Hz).  Frequencies below 254 Hz are better felt than heard and hence are not used.  Sensitivity for frequencies above 1024 Hz is rather poor and hence is not used.

Prerequisites for an ideal tuning fork:

1.      It should be made of a good alloy

2.      It should vibrate at the specified frequency

3.      It should be capable of maintaining the vibration for one full minute

4.      It should not produce any overtones

Methodology of using tuning fork:

The tuning fork must be struck against a firm surface (rubber pad / elbow of the examiner).  The fork should be struck at the junction of upper 1/3 and lower 2/3 of the fork.  It is this area of the fork which is capable of maximum vibration.

The vibrating fork should be held parallel to the acoustic axis of the ear being tested.

Advantages of tuning fork tests:

1.      Easy to perform

2.      Can even be performed at bed side

3.      Will give a rough estimate of the patient’s hearing acuity

The following tests can be performed using a tuning fork:

1.      Rinne test

2.      Weber test

3.      ABC test

4.      Bing test

5.      Politzer test

6.      Bing Entotic test

7.      Stenger’s test

8.      Gelle test

9.      Chimani-Moos test

Rinne test:

Rinne's test: is a tuning fork test used to clinically test hearing deficiencies in patients. It is designed to compare air conduction with bone conduction thresholds. Under normal circumstances, air conduction is better than bone conduction. 
Ideally 512 tuning fork is used. It should be struck against the elbow or knee of the patient to vibrate. While striking care must be taken that the strike is made at the junction of the upper 1/3 and lower 2/3 of the fork. This is the maximum vibratory area of the tuning fork. It should not be struck against metallic object because it can cause overtones. As soon as the fork starts to vibrate it is placed at the mastoid process of the patient. The patient is advised to signal when he stops hearing the sound. As soon as the patient signals that he is unable to hear the fork anymore the vibrating fork is transferred immediately just close to the external auditory canal and is held in such a way that the vibratory prongs vibrate parallel to the acoustic axis. In patients with normal hearing he should be able to hear the fork as soon as it is transferred to the front of the ear. This result is known as Positive Rinne test. (Air conduction is better than bone conduction). In case of conductive deafness the patient will not be able to hear the fork as soon as it is transferred to the front of the ear (Bone conduction is better than air conduction). This is known as negative Rinne. It occurs in conductive deafness. This test is performed in both the ears.

If the patient is suffering from profound unilateral deafness then the sound will still be heard through the opposite ear this condition leads to a false positive Rinne.

Use of Rinne test in quantifying conductive deafness:

Conductive deafness of more than 25 dB is indicated by negative Rinne with 512 Hz fork, while it is positive for 1024 Hz.  If Rinne is negative for 256, 512 and 1024 Hz then conductive deafness should be greater than 40dB.

Weber's test:

Is a tuning fork test (quick) used to assess hearing levels in an individual. This can easily detect unilateral conductive and unilateral sensorineural hearing loss. This test is name after Ernst Heinrich Weber (1795 – 1878).
Procedure:

Tuning forks used - 256 Hz / 512 Hz

Commonly used frequency is 512 Hz.

A vibrating fork is placed over the forehead / vertex / chin of the patient. The patient should be instructed to indicate which ear hears the sound better. In normal ear and in bilateral equally deaf ears the sound will be heard in the mid line. This test is very sensitive in identifying unilateral deafness. It can pick out even a 5 dB difference between the ears.

Theory:
A patient with a unilateral (one-sided) conductive hearing loss would hear the tuning fork loudest in the affected ear. This is because the conduction problem masks the ambient noise of the room, whilst the well-functioning inner ear picks the sound up via the bones of the skull causing it to be perceived as a louder sound than in the unaffected ear.

Inadequacies:

This test is most useful in individuals with hearing that is different between the two ears. It cannot confirm normal hearing because it does not measure sound sensitivity in a quantitative manner. Hearing defects affecting both ears equally, as in Presbycusis will produce an apparently normal test result.

Absolute Bone conduction test:

This test is performed to identify sensorineural hearing loss. In this test the hearing level of the patient is compared to that of the examiner. The examiner's hearing is assumed to be normal. In this test the vibrating fork is placed over the mastoid process of the patient after occluding the external auditory canal. As soon as the patient indicates that he is unable to hear the sound anymore, the fork is transferred to the mastoid process of the examiner after occluding the external canal. In cases of normal hearing the examiner must not be able to hear the fork, but in cases of sensori neural hearing loss the examiner will be able to hear the sound, then the test is interpreted as ABC reduced. It is not reduced in cases with normal hearing.

Bing test:

This is actually a modification of weber’s test.  The vibrating fork is placed over the mastoid process and when it ceases to be heard the examiner’s finger is used to occlude the external auditory canal.  In normal individuals the sound will be heard again.  This is because by occluding the external auditory canal the examiner is preventing sound from escaping via the external canal.  The external auditory canal acts as a resonating chamber.  If the vibrating fork is not heard again after the external canal is occluded then it is construed that the middle ear conduction is the cause for deafness.  In patients with pronounced deafness if the vibrating fork is heard after occlusion of external canal then deafness is construed to be due to labyrinthine causes.

Politzer test:

In this test the vibrating fork is held in front of open mouth and the patient is asked to swallow.  If the Eustachian tubes are patulous then sound will be intensified during swallowing.  If only one tube is patulous then sound will be accentuated only in that ear.  Sometimes normal persons too may not hear the vibrating fork.

 Bing Entotic test:

Hypothetically this test is supposed to differentiate between deafness due to ankylosis of foot plate of stapes from that of conditions interfering with mobility of other ossicles.  This test is actually of historic value only.  Eustachian catheter is passed and to one of its ends is attached a speaking tube.  If the patient is able to hear the fork better via this tube than that from the external auditory canal then middle ear ossicles other than foot plate of stapes is supposed to be at fault.

Stenger’s test:

This test is performed to identify feigned hearing loss and malingering.  This test is based on the auditory phenomenon known as “Stenger’s principle”.  This principle states that when two similar sounds are presented to both ears only the louder of the two would be heard.  Patients usually are not aware of this phenomenon.  When two similar tuning forks of same frequencies are made to vibrate and held simultaneously in the acoustic axis of both ears only the louder fork will be heard.  Loudness of vibrating fork can be adjusted by adjusting the distance of the fork from the external canal.  Usually the vibrating fork is held closer to the allegedly deaf ear of the patient.  The patient will not acknowledge hearing in that ear.  According to Stenger’s principle he should be able to hear the louder fork.  If the hearing loss in worse ear is genuine, patient will respond to the signal presented to the better ear.  This is known as negative Stenger’s test.  Feigning patient will not acknowledge hearing when louder sound is presented to the worse ear.  This is known as positive Stenger’s test.

Gelle test:

In this test, the air pressure in the external canal is varied using a Siegle’s speculum.  The vibrating fork is held in contact with the mastoid process.  In normal individuals and in those with sensorineural hearing loss, increased pressure in the external meatus causes a decrease in the loudness of the bone conducted sound.  In stapes fixation no alteration in the hearing threshold is evident.

Chimani-Moos test:

This is actually a modification of Weber test.  When the vibrating fork is placed on the vertex, the patient indicates that he hears it in the good ear and not in the deaf ear.  The meatus of the good ear is then occluded.  A genuine deaf patient will still be able to lateralize the sound to the good ear, where as a malingerer will deny hearing the sound at all.

Velopharyngeal insufficiency and its management

Velopharyngeal insufficiency and its management

Blow out fracture orbit current management concepts

Lingual thyroid

Respiratory medicine for nurses and paramedics

Foundation otolaryngology for nurses

Lingual thyroid and its management

Orbital disorders

Eosinophilic otitis media a literature review

Abstract:

Eosinophilic otitis media is actually a recent introduction. These patients may manifest with sudden hearing loss. There may be associated bronchial asthma and allergic rhinitis. Diagnostic criteria of this condition are rather vague. A review of literature shows that demonstration of eosinophils in the middle ear secretion of these patients could be considered to be pathognomonic of this condition.

Introduction:

Eosinophils are considered to be effectors for allergic reactions. Eosinophilic otitis media ¹ is a newly recognised entity causing intractable middle ear pathology. This condition is characterised by excessive accumulation of eosinophils in the middle ear cavity and is associated with persistent middle ear effusion. These patients usually suffer from bronchial asthma. The first description of this condition should be credited to Koch ² who first reported some patients with middle ear effusion which contained lots of eosinophils. He also added that these secretions were highly viscous and the middle ear mucosa was pinkish in color. The term eosinophilic otitis media was coined by Tomioka et al ³ in 1993.

Pathophysiology:

Pathophysiology of this condition is obviously allergy. These patients commonly had associated allergic rhinitis and branchial asthma. Eosinophils could have been probably attracted to the middle ear cavity by the presence of IL 5 ⁴ inside the middle ear cavity.

Features of Eosinophilic otitis media ⁵:

1. Sudden deterioration of hearing
2. Bronchial asthma
3. Allergic rhinitis
4. Intractable otitis media
5. Persistent otorrhoea

Incidence:

Incidence of eosinophlic otitis media is not clearly known. Literature search puts it to be rather common cause of otitis media with effusion.

Managment:

Patients diagnosed with this condition should be warned of the possibility of sudden deterioration of hearing.

Administration of systemic / topical steroids ⁶ could be of benefit in these patients.

Antihistamines and leukotreine receptor antogonists can also be used with benefit.

Grommet insertion is indicated in patients with acute sudden hearing loss.

References:

1. Iino Y, Kakizaki K, Katano H, Saigusa H, Kanegasaki S. Eosinophil chemoattractant in middle ear patients with eosinophilic otitis media. Clin Exp Allergy 2005;35:1370–6.
2. Koch H. Allergical investigations of chronic otitis. Acta Otolaryngol 1947;62(Suppl.):1–201.
3. Tomioka S, Yuasa R, Iino Y. Intractable otitis media in cases with bronchial asthma. Recent advances in otitis media. In: Mogi G, HonjoI, Ishii T, Takasaka T, editors. Proceedings of the second extraordinary international symposium on recent advances in otitis media. Amsterdam, New York: Kugler Publications; 1993. p. 183–186.
4. NonakaM, Fukumoto A, Ozu C, Mokuno E, Baba S, pawankar R, et al. IL-5 and eotaxin levels in middle ear effusion and blood from asthmaticswith otitis media with effusion. Acta Otolaryngol 2003;123:383–7.
5. Suzuki H, Matsutani S, Kawase T, Iino Y, Kawauchi H, Gyo K, et al. Epidemiologic surveillance of ‘‘eosinophilic otitis media’’ in Japan. Otol Jpn 2004;14:112–7 (In Japanese).
6. Iino Y, Nagamine H, Kakizaki K, Komiya T, Katano H, Saruya S, et al. Effectiveness of instillation of triamcinolone acetonide into middle ear for eosinophilic otitis media associated with bronchial asthma. Ann Allergy Asthma Immunol 2006;97:761–6.

VOL 1, NO 1 (2011) ONLINE JOURNAL OF OTOLARYNGOLOGY ISSN 2250- 0359

First volume of Online journal of otolaryngology (JORL) is given here. VOL 1, NO 1 (2011) ONLINE JOURNAL OF OTOLARYNGOLOGY ISSN 2250- 0359

Online journal of otolaryngology (JORL) First issue

First issue of online journal of otolaryngology (JORL) is available.  This free to access and free to publish e journal will be published 4 times a year.  You can start submitting  your work to the next issue right now following author submission guidelines mentioned in the website.

Just click on the image below to access the first issue of the journal.

Maxillectomy a review

Maxillectomy a review

View more presentations from Balasubramanian Thiagarajan

Retrotympanic Recesses

Introduction:

The posterior wall of middle ear cavity (Tympanum) is also known as retrotympanum. Important anatomic structures are lodged in this area. This area has assumed significance because of the difficulties encountered in clearing cholesteatoma from this area. This area is so narrow and has lot of crevises, it is very difficult to clear disease from this area.

This area is supposed to contain 4 important recesses. Each of these four recesses could hide cholesteatoma causing the surgeon to leave residual disease which could later recur. Precise knowledge of anatomy of this region is vital for the surgeon who wants to clear disease from this area. The recesses present in the retrotympanic area are:

1. Sinus tympani
2. Lateral tympanic sinus
3. Posterior tympanic sinus
4. Facial recess

Pyramidal eminence is the most prominent anatomical landmark of this area. This eminence hold the pyramidalis muscle. There are other prominences arising from this area projecting in various directions. They include:

1. External: Chordal ridge
2. Inferior: Pyramidal ridge
3. Superior: Suprapyramidal ridge
4. Internal: Ponticulus

The 4 types of retrotympanic recesses are found under these eminences.

Sinus tympani:

This is the most common and constant depression present in the retrotympanic area. Anatomically this sinus is located at the junction of the lateral and posterior walls of the tympanic cavity. Phylogentically this recess is considered to ba analogue of bulla tympanica seen in mammals. It lies between ponticulus superiorly and subiculum inferiorly. This recess is bounded by pyramidal ridge externally and promontory internally. Visualization of this area during middle ear surgery proves to be a challenge. During yester years small angled mirrors known as zinne mirrors were used. Now angled telescopes serves this function rather brilliantly. The sinus tympani is known to extend posteriorly up to the round window niche.

Types of sinus tympani:

Sinus tympani has been classified into three types depending on its depth. Note in type III it extends up to the level of lateral semicircular canal.

Lateral tympanic sinus:

Proctor described this sinus in 1969. This sinus lies between three eminences of styloid prominence. These eminences include:

Pyramidal eminence

Styloid eminence

Chordal eminence

Posterior tympanic sinus:

Posterior sinus of middle ear cavity is one of the recently identified anatomical sinus inside the middle ear cavity.
Serial temporal bone dissections have shown that it is present in nearly 90% of dissected bones.

Position: It lies just posterior to the oval window.

Depth: 1mm or less
Width: 1.5 mm or less

In nearly 60% of dissected specimen a ridge of bone arising from the floor of middle ear cavity separates it from sinus tympani.

In 8% of dissected specimen, the sinus tympani and posterior sinus merged together to form one confluent sinus.

It has been demonstrated that cholesteatoma / granulation tissue may lie within this sinus making removal difficult leading on to residual disease.
Retraction pockets may also occur close to this area.

Facial recess:

This recess lies between the promontory and tympanic annulus. It is bounded medially by the facial nerve and laterally by tympanic annulus. Running between these two structures at varying angulations is the chorda tympani nerve. Chorda tympani nerve always runs medial to the ear drum. Drilling in this area between the facial nerve, annulus and the angle formed by the chorda tympani nerve will lead into the middle ear cavity without causing a breach in the ear drum. This approach is used in cochlear implant surgery to place the electrode in the round window area. Hypotympanum can also be approached through this approach.

Subiculum:

This is the posterior extension of promontory separating oval and round windows.

Ponticulus:

Rarely a spicule of bone arises from the promontory above the subiculum and runs to the pyramid on the posterior wall of the middle ear cavity. This spicule of bone is known as the ponticulus.

Submission of articles to online journal of otolaryngology

Introduction:

Online journal of otolaryngology has been started.  It is free to access and free to publish.  You can read / submit articles to this journal by going through a simple registration process which is free.  Articles submitted will be peer reviewed before publication.  Publication of selected articles is absolutely free.

Click on the image below to read a short tutorial on article submission to this journal.

Click on the image below to access the journal.