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Tympanosclerosis
By
Dr. T. Balasubramanian M.S. D.L.O.
Definition: is deposition of
acellular hyaline and calcium deposits within the submucous layer of
the tympanic membrane / submucous membrane of the middle ear cavity.
In a majority of patients these plaques are so insignificant that
they cause very little impairment in the hearing ability of the
patient. These plaques could be likened to healed scar
tissue.
When present over the tympanic membrane these plaques
appear like a whitish cresentic shaped plaques.
Causes:
1. Could be caused by resolved otitis media.
2. Trauma
3. Chronic otitis media with effusion
4. After recurrent bouts of acute otitis media (middle
ear tympanosclerosis)
5. After grommet insertion
6. Eustachean tube obstruction
7. Autoimmune process occurring within tympanic membrane
Fig showing
healed central perforation with tympanosclerotic
plaque
Histology:
There is hyalinisation of the subepithelial connective
tissue of the tympanic membrane and middle ear cavity. Calcifiation
is commonly present in these lesions. Osteoneogenesis can also occur
within these lesions.
Fig showing histology
of tympanosclerosis
Plaques occurring in the tympanic membrane is limited to
lamina propria. Deposition of bone due to osteoneogenesis in the
attic region may cause fixation of malleus and incus leading on to
conductive deafness.
Pathophysiology:
It has been postulated that after an episode of otitis
media with effusion / or acute otitis media the collagen undergoes
degeneration and subsequent dystrophic calcification and formation
of tympanosclerosis.
Treatment:
Most of the patients with tympanoslerosis are symptom
free and the finding is purely accidental. If these patients have
significant conductive deafness then surgical removal of the plaques
from the tympanic membrane and fashioning a neo tympanic membrane
using temporalis fascia graft can be attempted. If these plaques
involve the attic area and cause ossicular fixation leading on to
conductive deafness, ossiculoplasty can be attempted.
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