Myringoplasty or Tympanoplasty (interchangeable)
Type I Myringoplasty
- An
operation to repair an ear drum
Procedure Name:
Myringoplasty
Surgical
restoration of a perforated tympanic membrane by grafting
ICD-9 Description:
Surgical
restoration of a perforated tympanic membrane by grafting
ICD-9 Code Family:
19.4 -Type I
Description:
Surgical
reconstruction of the hearing mechanism of the
middle ear, with restoration of the drum membrane.
The
ENT medical profession has defined different
types of severity levels of damage to the eardrum
and the middle ear depending on the seriousness of the
underlying problem in addition to the eardrum.
Type I and Type II are discussed in detail, below.
Type III Tympanoplasty is indicated when most of
the ossicles have deteriorated or are
non-functioning, but where there is still a
functioning stapes connected to the round
window. It involves placing a graft between the
tympanic membrane and the stapes, essentially a
prosthetic middle ear conducting mechanism.
(occuloplasty)
Type IV Tympanoplasty is used when the stapes has
become detached from the round windows of the inner
ear or where there is an air pocket, causing non
conductivity of vibrations.
Type V Tympanoplasty is used when there is either
an obstruction in the inner ear or there is a hole
in the round window of the inner ear.
Although the words
Myringoplasty and Tympanoplasty are used
interchangeably by the medical profession, The
ICD-9 coding reference assigns The term
Tympanoplasty to the Type II through Type V
procedures.
Myringoplasty Type I Overview
There are two
myringoplasty procedures defined in the 2007 ICD-9
reference under the 19.4 code: Type I procedures and
Type II procedures. Type I procedures involve
surgical procedures to repair parts of the middle
ear: the round window, a fenestra in the
semi-circular canal, and repairs to the
ossicles: the stapes,
incus, or malleus.
As part of this procedure, the surgeon may insert
grommets. However, grommets are usually used
only with children.
A Type II procedures myringoplasty is the process by which a hole in
an eardrum is repaired where there is also something
also wrong with the malleus connection.
There are a variety of surgical techniques to
close a hole from a burst ear drum, but
basically all procedures attempt to encourage the
body to heal the opening. This type of surgery is
typically quite successful in closing most
perforations permanently. The ability of any hearing loss
to improve from the operation has about an 80% success rate.
Qualified persons: There are two types of
surgeons qualified to perform ear drum repair
operations: an ENT - (Ear Nose and Throat surgeon), and Head and
Neck surgeons.
Surgery to reconstruct the
tympanic membrane (eardrum) can be performed either
under local with intravenous sedation or general
anesthesia. Many patients prefer to be completely
asleep and choose the general anesthesia route.
A
myringoplasty is
usually done as a day-surgery local or mild
general anesthesia basis in about 20 - 30 minutes.
Myringoplasty
Methods
The surgeon will first
decide what to use to initially cover up the hole.
The surgeon may use a combination of thin paper or
using "live" tissue from the same person. In the
past, tissue from cadavers was used but in the
United States is out of favor.
-
Paper method: a thin
paper patch is placed on the eardrum to act as a
basis for skin growth. Several applications of the
patch (up to three or four over 3-6 weeks) may be
required before the perforation closes completely.
To encourage a ear drum to heal, a chemical
(usually hyaluronic acid) is dabbed onto the edges
of the hole and paper to stimulate growth.
-
Live tissue method: A "clip"
or small sample of skin from behind the ear is
excised and is used as the hole patch. The clip
includes the dermis and is still "alive" and will
assist with the healing of the ear drum.
With small instruments,
the surgeon will go through the ear canal and
delicately attach the live skin tissue to the
outside of the hole. It will not completely cover
the hole to encourage new skin growth.
-
Recently,
scientists in Brazil
have developed a
biomembrane from the natural rubber tree by
extracting the rubber and then removing harmful
proteins that may cause allergies. The membrane has
been very successful in closing holes in
myringoplasty operations.
Myringoplasty
Procedures
A myringoplasty is usually performed under general
anesthesia in a hospital setting, unless the hole is
very minor, or it is a simple operation to insert
grommets.
A special operating microscope is used by the
surgeon.
The microscope
helps to magnify the view of the ear structures,
giving a more detailed image to the ear surgeon. If
the perforation is very large or the hole is far
forward and away from the view of the surgeon, it
may be necessary to perform an incision behind the
ear. Once the hole is
exposed fully, the perforated remnant is rotated
forward, and the bones of hearing are inspected.
There may be scar tissue and bands surrounding the
bones of hearing. These can be removed either with
micro hooks or laser.
An incision is made into
the ear canal and the remaining eardrum is elevated
away from the bony ear canal and lifted forward.
Ear drum after incision
Image courtesy;
Head & Neck Surgical
Group, PLLC, Jackson MS.
A small piece of skin is "pinched" from the coating
of a muscle immediately above the ear. The tissues
are thinned and dried for a few moments. An absorbable
sponge is sometimes placed under the ear drum
to allow for support of the graft. The graft is then
inserted underneath the remaining drum remnant and
the drum remnant is folded back onto the perforation
to provide closure.
More gelatin sponge is
generally placed against the top of the graft to
hold it into position and prevent it
from sliding out of the ear when the patient blows
his nose or sneezes.
If opened from behind, the
ear is then stitched together, a sterile patch is
placed on the outside of the ear canal and the
patient returns to the recovery room. Generally, the
patient can return home within a few hours.
Antibiotics are given along with a mild pain
reliever.
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Eardrum with
a hole in it |
Same eardrum
repaired after myringoplasty |
After the Myringoplasty operation
You will probably be
discharged the same day. Antibiotics and sometimes a
decongestant will be precribed.
Keep water away from the
ear. In fact, the surgeon's nurse(s) may give you a
special shower cap so the ear remains dry when you
take a shower. Try not to blow your nose. Most individuals can return to work after one
to two weeks unless they perform heavy physical
labor, in which case they can return after
three weeks.
After 7 days, the stitches
are removed. After about 2 weeks any gelfoam packing
(sponges) that was used in the operation
After three weeks, all
packing is completely removed under the operating
microscope in the office. It can then be determined
whether the graft has fully taken. In over 98
percent of cases, the tympanoplasty procedure is
successful and a hearing test is performed at six to eight weeks after the operation.
You will be tested with an audiometric device
before and some weeks after the operation. Your
hearing test results (audiogram) will often show a
hearing improvement like the following chart:
Myringoplasty Success Rates
Failure of tympanoplasty
can occur either from an immediate infection during
the healing period, from water getting into the ear,
or from displacement of the graft after surgery.
Most patients 98% can expect a full "take" of the
grafted eardrum and improvement in hearing. After
two to three months, water can be allowed to enter
the ear and the patient can even return to swimming.
Possible
Complications:
Postoperative dizziness
and imbalance can be present for about a week after
surgery and are usually very mild. Dizziness is
uncommon in operations that only involve the eardrum
itself. It is more common if the ear bones has to be
repaired or manipulated. Generally, all imbalance
and dizziness will be resolved after a week or two.
Besides failure of the
graft, there may be further hearing loss due to
unexplained factors during the healing process. This
occurs in less than one percent of individuals
undergoing the operation.. A total hearing loss from
tympanoplasty surgery is extremely rare.
Tinnitus or noises in the
ear, particularly an echo-type feeling, may be
present as a result of the perforation itself.
Usually, with improvement in hearing and closure of
the eardrum, these sensations clear up. However,
tinnitus is unpredictable. In some cases, it can
temporarily worsen after the operation. There is no
explanation for this temporary situation, but it is
rare for the tinnitus to be permanently worse after
surgery.
A small nerve goes through
the ear called the chorda tympani nerve. This nerve
goes to the taste buds of the tongue. Should this
nerve be stretched or cut during tympanoplasty
surgery, there may be a transient period of one or
two months after surgery where there is a slight
metallic or salty taste to food. Generally, the
nerve connections will regenerate and taste will
return to normal. The abnormal taste sensation
rarely lasts longer than six months.
Long Term Effects of a Myringoplasty on Hearing
The long term effects of a burst eardrum
and subsequent operations on the ear will be a
function of the size of the hole that was repaired,
and how many times the eardrum has to be worked on
before the hole is completely healed. With any
tissue that heals, there is scar tissue residue;
with any operation on body tissue, there is also
scar tissue residue. Scar tissue is the natural
end-result of a successfully healed eardrum.
The eardrum's purpose is to vibrate. the
buildup of scar tissue inhibits that vibration
function; the greater the scar tissue, the less the
eardrum will vibrate, affecting the ability to hear.
As a rule of thumb, a hole in the eardrum that heals
on its own within a few weeks or months will have
minimal effect on hearing. A myringotplasty should only
affect hearing loss to a maximum of 5%; a
tympanoplasty can affect hearing negatively up to
20%. Then again if the surgeon does an
excellent job with a tympanoplasty and the hole is
relatively small, hearing loss will be negligible.
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