Tympanosclerosis is scarring and thickening of the eardrum. An excess of fibrotic tissue forms, leading to whitening and reduced transparency. It is common among children after treatment of glue ear using a grommet, occurring in around one in four cases. It is not known what causes the problem, whether it is the glue ear, the grommet or something else.
Usually the thickening is so minor that the individual does not notice. Rarely though it can cause a reduction in hearing. This is usually after recurrent glue ear, infections and surgery. It does not happen often in most children who only have one set of grommets.
Myringosclerosis and intratympanic tympanosclerosis is caused by the middle ear tissues becoming calcified. Intratympanic tympanosclerosis involves any location within the middle ear other than the eardrum. This includes the ossicles, middle ear mucosa and the mastoid cavity.
Chalky white patches may be visible on the eardrum when it is examined with an otoscope. Hearing tests may show a reduction in hearing acuity. Tympanometry gives a specific reading which helps diagnose the condition. Sometimes a CT scan can be used to tell if there is also disease in the middle ear. Cholesteatoma may appear in a similar way but the whiteness is behind the tympanic membrane rather than within it.
Atherosclerosis may lead to tympanosclerosis. Research is ongoing as to whether cholesteatoma is related. The condition comes about because of increased activity of fibroblast cells. This leads to the creation of excess collagen. Calcium then forms plaques within the membrane.
Hearing aids may be used if there is a reduction in hearing. Sometimes surgery is performed to cut away sclerotic areas and repair the ossicles. Outcomes vary.
The prognosis is that after 10 years most cases are not suffering any noticeable deafness. The degree of sclerosis often stabilises after 3 years. The majority of research has not been carried out on the general population. Instead it was on patients who were given tympanostomy tubes at some point in their lives. Out of children who had glue ear and a grommet between 23% and 40% had a degree of the condition.
Dr Toby Bateson ZenPlugs Ltd