Condition: Traumatic tympanic perforation
Definition:
Tympanic membrane, or eardrum, is a stiff but movable oval membrane inside
the ear. It separates the outer ear canal from the inner ear. A perforation
involves a tear or hole in the tympanic membrane. As a result of this
perforation a conductive hearing loss may result (Berger, 1989). There may
also be ear discharge, tinnitus (ringing or buzzing sound in the ear), or
dizziness. This discharge may be clear, bloody, or yellowish and thick
(Wolters Kluwer April 2010.)
Perforation of the tympanic membrane refers to either a “partial” or total hole
in the tympanic membrane. It represents a hole in the eardrum establishing a
communication between the middle and external ear (Ibekwe et. al, 2007).
Perforation of the tympanic membrane produces a conductive hearing loss in
the affected ear (Berger, 1989).
Pathophysiology:
Perforations may spontaneously heal within time but in the case of traumatic
perforations a tympanoplasty may be performed to reduce the risk of infection
(Omadasun, 2002; Merwin & Boies, 1980). Larger perforations are usually
associated with chronic infections of the middle ear space and these may be
more likely to require surgical intervention (Gelfand, 2009). Sub categories
include marginal, central and attic perforations. Marginal perforations involve
the fibrous annulus, and central perforations do not involve the fibrous
annulus (Oghalai, 2006). Perforations classed as an ‘attic perforation’ usually
involve the Pars flaccid (Gelfand, 2009). Central perforations seem to be most
common type (Legget, 2010) and one reason for traumatic perforations are
from “overpressure”, such as those caused by a hit (Afolabi et. al, 2009)
The result of tympanic membrane perforation results in a conductive hearing
loss. This occurs because the advantages of ratio between the area of the
tympanic membrane and the oval window is reduced, decreasing the
vibrations transmitted (Gelfand, 2009). Consequently the area to ratio
difference between the tympanic membrane and oval window is also reduced.
Whereas a fully intact membrane would give an approximate pressure gain at
the oval window of times twenty, a perforated eardrum would not provide the
same pressure gain. This means a significant amount of the impedance
matching property of the middle ear is reduced. The malleus is attached to the
tympanic membrane by the fibrous layer (Howard, 2009) and a perforation
can affect this attachment by reducing the vibrations transmitted by the
ossicular chain (Gelfand, 2009).
A healed perforation can form a neomembrane which is a thin membrane
made up of mucosal and ‘squamous epithelia layers’, with no fibrous layer
present (Howard, 2009). These neomembranes are often mistaken for
perforations because the membrane is so thin or because they have retracted
in to the middle ear (Howard, 2009). They should not be confused with
perforations.
Perforations due to burns can often become infected and the patient may
experience otorrhea. Trauma to the tympanic membrane and the middle ear
can be caused by overpressure from a slap on the ear, assault or road traffic
injury. Thermal or caustic burns, penetration by instruments and barotraumas
may also cause traumatic perforations. Perforations due thermal injury was
caused by metal spark perforating the tympanic membrane during welding
(Naumann et al 1998;
Symptoms:-
Symptoms vary between individuals and depend on the size and location of
the perforation (Gelfand, 2009).

Tinnitus

Sudden hearing loss (Afolabi et. al, 2009)

Otalgia (ear pain)

Bleeding

Potential infection of the middle ear (Amadasun, 2002)
Epidemiology: - Traumatic perforations are usually caused by a sudden
force, change of pressure or object that is substantial enough to create a hole
in the eardrum (Greenburg, et. al, 2005).
Common causes include:

Accidental or purposeful insertion of an object into the external auditory
meatus (EAM) such as a pencil or sewing needle (Oghalai, 2006)

Sudden force such as a jet of water (Shanks & Shohet, 2009), a slap to
the nose (Amadasun, 2002), or as a result of an explosion (Kronenberg
et.al, 1993)

Pressure changes between the environment and ear; barotruama,

Ear syringing or suctioning (Amadasun, 2002)

Thermal injuries are common in occupations such as welding, due to metal
sparks entering the ear Jung, K.S.K.T., 1999).

Surgical removal of foreign bodies

Infections such as purulent acute otitis media and chronic otitis media
(Berger G.1989.)

Trauma to the tympanic membrane and temporal bone (Berger G.1989)

Latrogenic - myringotomy with tympanostomy tube placement (Berger
G.1989.
Perforations can affect any one of any age and this is unpredictable due to the
sudden nature of the perforation. However it is more common in certain
groups of people.

Traumatic perforation of the tympanic membrane has been reported to
occur in up to 36.5% of those injured by terrorist attacks and up to
63.2% of casualties following an explosion (Cooper, et. al, 1983, cited
in Kristensen, 1992)

Estimates of the prevalence vary with estimates ranging from 1.4 to 8.6
per 100,000 people (Griffin, 1979 & Kristensen et. al, 1989, cited in
Kristensen, 1992)

A blow to the head and neck can also lead to a traumatic perforation,
with Thermal burns that result in perforations are more prevalent in
occupations such as welders (Naumann et.al, 1998, pp136)

Perforations as a result of a sudden blast or explosion are more
common in times of unrest or war (Kronenburg et. al, 1993)

Those caused by a sudden force such as a slap may be associated
with assault (Glasscock, M.E. & Gulya, A.J., 2003). Estimates suggest
that up to 50% of abusive injuries to this head and neck result in a
perforation.
Management:
As up to 94% of perforations heal naturally (Berger, G, & Gelfand, 2009)
medical intervention is not usually necessary. In these situations monitoring of
the perforation is usually sufficient. However it is necessary in some cases to
intervene and options include:

Using a specialised plug with a topical antibiotic to prevent an infection
(Omadasun, 2002)

Ensuring the ear is kept dry to discourage bacteria from growing in the
warm and moist conditions (Chukuezi, A.B. & Nwosu, J.N, 2009)

Surgery such as a tympanoplasty or myringoplasty for larger
perforations (Gelfand, 2009). Both involve using a tissue graft to repair
the perforation. Surgery may also prevent future ear infections (Moller,
1988-1997)

Pain killers may be given to reduce the pain (Wolters Kluwer April
2010.)
There is some evidence that treating tympanic membrane perforations
surgically may resolve symptoms, improve the patients hearing, and may
prevent further ear infections (Moller, A.R., 2006)
CONDITION: Traumatic (tympanic) perforation in left ear
Otoscopy result
Notes: - The right tympanic membrane appeared to be normal under otoscopy.
The left ear was noted to have a central perforation in the inferior posterior
part of the tympanic membrane beside the Umbo. Otoscopy can also be
useful in order to reveal the cause of the perforation, traumatic perforations
usually have sharp ragged edges and blood can often be see in the EAM or
middle ear (Naumann et al 1998, pp136). Sub categories of TM perforation
include 1) Marginal, 2) Central and 3) Sub total central - This term is used by
some ENT surgeons in the UK and refers to a very large central perforation
surrounding one side of the umbo, Central perforation seems to be most
common (Legget, 2010. Basic Path physiology slides).
Other potential otoscopy findings
1) Safe perforation of the anterior part of the
drum, a common cause of perforations in this
position is a persistent defect after the extrusion
of a grommet (Saunders, M, 2003)
2) Inferior perforation, this is more likely to be as a result of
chronic middle ear infection (Saunders, M, 2003)
3) Posterior perforation, although
posterior perforations may represent
more serious diseases such as
cholesteatoma, this is well described and
dry. It is possible to make out the
posterior margin of this defect. Traumatic
perforations (e.g. barotraumas) are often
posterior and liner, like a tear rather than
a round hole.
(Saunders, M, 2003)
Perforation
Tuning forks
Weber:
(non central
Lateralises to the left
Rinne:
perforation
Right ear
Left ear
positive
negative
Notes: The Weber test shows lateralisation to the left side with conductive
hearing loss. The Rinne result for the right ear indicates that the sound was
heard better by air conduction than bone conduction. The negative left Rinne
shows that the sound was perceived to be better via bone conduction than air
conduction. Both tests results suggest CHL on the Left.
Pure tone audiometry and uncomfortable loudness levels (non central
perforation)
RIGHT
LEFT
-10
0
0
10
10
20
20
30
30
Hearing level (dB)
Hearing level (dB)
-10
40
50
60
70
80
40
50
60
70
80
90
90
100
100
110
110
120
120
130
130
140
140
125
250
500 1000 2000
Frequency (Hz)
4000
8000
125
250
500 1000 2000
Frequency (Hz)
4000
8000
Notes: PTA results indicate a unilateral mild-moderate sloping mixed hearing loss;
masked bone conduction was required at 500Hz, 1000Hz, 2000Hz and 4000Hz in
the left ear, due to the presence of an air-bone gap of more than 10dB. A large air
bone gap in the suspect ear could indicate the incidence of ossicular chain
disruption caused by the perforation. Profound sensor neural hearing loss (SNHL) in
the suspect ear could indicate labyrinthine window rupture caused by the perforation
(Milchard, 2009; Naumann et al 1998, pp136 & Katz, et al., 2009).
Tympanometry
Right
Left
Notes: A 226Hz probe was used at all times using the diagnostic mode at a
rate of 50da pa per second. Flat trace for left ear is the expected result for a
left TM perforation. The abnormally high ear canal volume result (above 2.0ml)
for the left ear supports the otoscopy findings that show a small central inferior
posterior perforation. This is as the volume of the middle ear cavity has also
been recorded.
The right ear has results within the normal range, of between -50 and +50
daPa for middle ear pressure and between 0.3-1.6 ml for middle ear
compliance.
Acoustic reflexes (central perforation)
Threshold
Right
Stimulus ear
Left
Contra lateral
Ipsilateral
Stimulus
Ipsilateral
Contra lateral
> 100 dB
80
500Hz
> 100 dB
80
> 100 dB
85
1000Hz
> 100 dB
90
> 100 dB
90
2000 Hz
> 100 dB
85
> 100 dB
85
4000 Hz
> 100 dB
80
> 100 dB
65
BB Noise
> 100 dB
70
Notes: Reflexes could not be obtained for the ipsilateral left reflex or the
contra lateral right reflex because we stop increasing the intensity of the
stimulus if there is no result for 100 dBHL. The reason for the absences is
because of the ‘probe ear and stimulus ear principles’ (Katz et. Al 2009).
These state that if there is a conductive hearing loss in the probe ear, then the
acoustic reflex of that middle ear will be absent. Results from the contra
lateral left and ipsilateral right reflexes are within the normal threshold range
of 75-90 db for pure tones and 50-75db for broad band noise.
Differential diagnosis: Left facial nerve paralysis results might be almost
identical to these expected results. Acoustic reflex results are not sufficient to
diagnose TM perforations, however when combined with the other test results,
particularly otoscopy results, correct diagnosis of TM perforation should be
straightforward. (Aage R. Moller 1988-1997).
Otoacoustic emissions
N/A
N/A
Notes:
Transient Evoked Otoacoustic emissions (TEOAE’s) testing was carried out
between 500 Hz to 4 kHz. ILO 292 measurement system was used. A
standard non-linear stimulus paradigm was used at a rate of 50 clicks per
second in order to minimise the risk of stimulus artefacts. Definition of a
present TEOAE was based on the reproducibility percentage with values
above considered to be a possible TEOAE, above 75% a definite TEOAE and
below 50% the procedure was repeated once and then deemed to be too
noisy to obtain an accurate measurement. It was also based on the dispersion
of the TEOAE waveform with high frequency components appearing first,
followed by low frequency components. The overall shape of the OAE was
also taken into account. This test is particularly useful in children, as it does
not require patient response (OAE Guide, 2009)
The detection of distortion-product otoacoustic emissions depends on the
viability of the ear's conduction apparatus. However, tympanic membrane
perforations and other conductive disorders have not been fully investigated
with regard to the examination.
General comments
This battery of tests will enable the identification of the type of perforation and
do so at an early stage, this enables proper management and treatment to be
carried out, so that healing time can be minimised, and so that complications
are avoided.
References:
Berger G. Nature of spontaneous tympanic membrane perforation in acute
otitis media in children. J Laryngol Otol. 1989 Dec;103(12):1150-3.
Amadasun, J.E.O., ‘An observational study of the management of traumatic
TM perforations’, The Journal of Laryngology & Otology, March 2002, Vol.
116
Oghalai, J.S., 2006, ‘TM, middle ear and mastoid disease’, Baylor College of
Medicine, Otolaryngology- head and neck surgery, Retrieved 28th February
2010 http://www.bcm.edu/oto/jsolab/tm_me_mastoid/tympanicmembrane.htm
Shanks, J & Shohet, J, 2009, J Katz, L Medwetsky, R Burkard & L Hood,
Handbook of Clinical Audiology, 6th edn.,
Gelfand, S.A., 2009, Essentials of Audiology, Thieme Medical Publishers Inc.,
New York, USA, pp 171-172
Kronenberg, J, Ben-Shoshan, J & Wolf, M, ‘Perforated TM after blast injury’,
Kristensen, S, ‘Spontaneous healing of traumatic tympanic perforation in man:
A century of experience’, The Journal of Laryngology and Otology, Vol. 106,
1992, pp 1037-1050, retrieved 1st March 2010
http://journals.cambridge.org/download.php?file=%2FJLO%2FJLO106_12%2
FS0022215100121723a.pdf&code=576126299d8f703f74f024857fd4885c
Ibekwe, T.S., Ijaduola, G.T.A., Nwaorgu, O.G.B., ‘Tympanic perforation
among adults in West Africa’, Otology & Neurotology, 2008 Vol. 28, pp 348352
Afolabi, O.A., Aremu, S.K., Alabi, B.S. & Segun-Busari, S, ‘TM membrane
perforation: An aetiological BMC Research Notes 2009, retrieved 28th
February 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2785833/pdf/1756-0500-2232.pdf
Chukuezi, A.B. & Nwosu, J.N., ‘An unusual cause of acute TM perforation: a
case report’, International Journal of Medicine and Medical Sciences, Vol 1(4),
2009, pp 97-98, retrieved 28/02/2010 from:
http://www.academicjournals.org/ijmms/PDF/pdf2009/Apr/Chukuezi%20and%
20Nwosu.pdf
Naumann, H.H., Helms, J, Herberhold, C, Jahrsdoerfer, R.A., Kastenbauer,
E.R., Panje, W.R. & Tardy Jnr., M.E., 1996, Head and neck surgery: Volume
2: the Ear, Thieme Medical Publishers Inc., New York, USA, pg 136
Roeser, R.J., Downs, M.P., 2004, Auditory disorders in school children, 4th
end., Thieme Medical Publishers Inc, New York, USA, pg 82, Retrieved 1st
March 2010
http://books.google.co.uk/books?id=6jRYWYSg29MC&pg=PA82&lpg=PA82&
dq=pathophysiology+of+traumatic+tympanic+perforation&source=bl&ots=Goi
Greenburg, M.L., Hendrickson, R.G., Silverberg, M., Campbell, C.J., Morocco,
A.P., Salvaggio, C.A., Spencer, M.T., 2005, Greenburg’s text-atlas of
Emergency Medicine, Lippincott Williams & Wilkins, Philadelphia. USA,
Retrieved 1st March 2010 from:
http://www.ksoem.org/upload/data/1012990110.pdf
http://books.google.co.uk/books?id=tjZttRRH8H8C&pg=PA146&dq=infection+
of+tr
Glasscock, M.E. & Gulya, A.J., 2003, Glasscock-Shambaugh surgery of the
ear, BC Decker Inc., Ontario, Canada, pg 364, Retrieved 1st March 2010 from:
http://books.google.co.uk/books?id=IvYbOyS6_i0C&printsec=frontcover&dq=
Glasscock-Shambaugh+surgery+of+the+ear&source=bl&ots=IDD6P01I-
Howard, Matthew, L. (2009) Middle Ear, Tympanic Membrane, Perforations,
California, medicine from: http://emedicine.medscape.com/article/858684
Naumann H.H., Helms J., Jahrsdoerfer R. (1998), Head and neck surgery,
Volume 2, Thieme Medical Publishers Inc., New York, USARetrived
03.03.2010 from:
http://books.google.co.uk/books?id=MK1brjp6gaEC&pg=PA136&dq=traumatic
+perforation+of+tympanic+membrane&cd=6#v=onepage&q=traumatic%20per
(Kyoo Sang Kim Tae Jung 1999)
:-fromhttp://www.ksoem.org/upload/data/1012990110.pdf
Leggett, M. (2010). Otosclerosis, ISVR1011-18718-09-10. [Lecture notes]
Otosclerosis. Basic Pathophysiology of Hearing and Balance Module.
University of Southampton, ISVR
Hearing (its physiology and path physiology) by (Aage R. Moller)
Stanley A. Gelfand Hearing (an introduction to psychological and
physiological acoustics)
Milchard, A, 2009 lectures on BHA Module :-1st semestre lectures, plus BSA
procedure
Saunders, M, 2003, Other conditions of TM perforation, Retrieved 1st May
2010 from: http://www.bris.ac.uk/Depts/ENT/otoscopy_tutorial.htm
Wolters Kluwer Updated 7 April 2010, Micromedex Updated 4 May 2010,
Cerner Multum from: - http://www.drugs.com/cg/tympanic-membraneperforation-inpatient-care.html