NORMAL EARDRUM - tense and devoid of any retained epithelial debris middle elastic layer the normal migration of the epithelial layer from the drum along the meatal walls to the exterior.
RETRACTION POCKETS AND ATELECTASIS The 1-st condition: the closing of the Eystachian tube The 2-nd condition: some parts of the eardrum have no elastic layer The pressure inside is negative The pressure outside is positive Impression of the parts of the eardrum and accumulation of debris in it
RETRACTION POCKETS AND ATELECTASIS
RETRACTION POCKETS AND ATELECTASIS
RETRACTION POCKETS Part of the eardrum without elastic layer (atelectasis) Retraction pocket Huge retraction pocket with cholesteatoma
PERFORATION OF THE DRUM
Three main types of perforation of the tympanic membrane are found in patients with chronic otitis media. They are central, marginal and attic.
In this type of perforation a part of the membrane remains all round, and the fibrous annulus remains intact even though the perforation may be a very large one .
An attic perforation is one situated in the pars flaccida. Perforations of this kind are associated with the most serious variety of destructive middle-ear disease because of their invariable association with an invading cholesteatoma.
These are perforations in which the fibrous annulus is involved. This means that disease of bone is present and that such perforations are inevitably associated with osteitis, often with granulations and with cholesteatoma formation.
Chronic otitis may be confined to the mucosa, or may involve and destroy bone.
It may be classified as follows:
A) Serous otitis
B) Mucous otitis or 'glue ear'
A) Tubo-tympanic suppuration
B) Attico-antral disease
3. Tuberculosis of the ear.
It is the result of acute otitis media which has left a permanent perforation.
The discharge is mucoid or mucopurulent. It may be constant, but it may dry up at times to reappear with the onset of upper respiratory infection or accidental entrance of water into the ear.
The perforation of the drum is central, i.e. it does not involve the fibrous annulus. The middle-ear mucosa may be swollen and oedematous and may produce polyps.
There is usually a conductive hearing loss present.
In untreated disease there is danger to the hearing, though there is rarely any threat to life.
There is no evidence of cholesteatoma or disease of bone.
This disease is not only destructive to hearing, but may be dangerous to life by virtue of its complications.
Sometimes the symptoms are quite minor until such complications develop. There are two forms of the disease:
(1) suppurative disease
(2) cholesteatomatous disease .
These may be combined. There is destruction of bone towards the middle cranial fossa, posterior cranial fossa.
There is destruction of the mastoid cells with pus, polyp and granulation formation, and possibly some exposure of the dura or the lateral sinus.
Discharge, which may be yellow, copious and foul, is a common feature, and hearing loss is marked. Occasionally, however, the discharge is scanty.
Perforations of the drum are as a rule posterior, but do not necessarily follow any particular pattern when the disease follows an acute otitis media.
Granulations are typical of disease of bone and grow on dead or dying bone.
Discharge can be scanty, but is foul and creamy if secondary infection is present. It comes from a perforation which involves the attic or the posterior margin of the drum.
If there is little infection the discharge may consist of a flaky, waxy deposit which may obscure the attic or marginal perforation, which may be difficult to identify .
Cholesteatoma is the result of invasion by squamous epithelium and the accumulation of its products in the middle ear and mastoid. The suffix '-oma' may suggest that it is a tumor. This is not the case, though as it expands it is destructive by pressure on other structures.
Cholesteatoma is classified as
(1) congenital cholesteatoma,
(2) acquired cholesteatoma,
which may be primary or secondary.
CHOLESTEATOMA Closing the tube The retraction pocket Huge retraction pocket and cholesteatoma Bone destruction and spreading infection into the middle cranium fossa
The second –
squamous metaplasia of the middle-ear mucosa may occur in response to a chronic infection
cholesteatoma Retraction pocket
CHOLESTEATOMA The ingrowth of squamous epithelium around the edges of a perforation , especially in the case of marginal perforations
X-ray examination of mastoid cells
Normal Chronic purulent otitis
Ear surgery may be divided into two types:
Reconstructive (Hear-improving or otoplastic)
Curative type of surgery
The main aim is to clean middle ear and to eliminate all pathological changes of mucous membrane, bone.
The most typicall operation is called radical middle ear operation or generalcavitary . Three cavities (tympanum, mastoid cells and meatus externus) are combined into one big cavity. All pathologic findings are eliminated.
It is prescribed in patients with:
non-effective conservative treatment;
substantial destructive process in temporal bone;
when cranial complications are suspected or present.
Hear-improving or reconstructive surgery
The main aim is to reconstruct the passage of acoustic ways through the structures of middle ear. The surgeon reconstructs ossicle chain, covers the perforation of drum and screens round window. The volume of an operation depends of the intensity of destructive process in middle ear.
All operations are divided into 5 main types.
I type of tympanoplastic operations
It is prescribed in patients with perforation of the drum but when the ossicles are intact ( myringoplastic ).
The transplantat is put on the remains of the eardrum
II type of tympanoplastic operations
It is prescribed in patients with perforation of the drum and blasted handle of malleus .
The transplantat of new eardrum is put on the head of the malleus
III type of tympanoplastic operations
It is prescribed in patients with perforation of the drum and blasted malleus and incus .
The transplantat of new eardrum is put on the stapes and the small new tympanis cavity is formed .
IV type of tympanoplastic operations
It is prescribed in patients with perforation of the drum and blasted all ossicles. But the plate of the stapes in oval window must be mobile .
In this type of operations the transplantat of new eardrum plays role of screen to the round window.
So acoustic waves go through the oval window to the perylimph but not through the round window. Patient can hear due to the difference of sound pressure to the windows.
V type of tympanoplastic operations
It is prescribed in patients with perforation of the drum and blasted all ossicles. And the plate of the stapes in oval window can’t move .
In this type of operations the new oval window is created and the transplantat of new eardrum plays role of screen to the round window.
This type of operations is not used anymore nowdays.