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I am sorry to hear about your son's diagnosis
Surgery is definitely recommended for cholesteatoma
There are two types of surgical procedures that can be carried out, Closed or open cavity, and this depends on the type of cholesteatoma, and sometimes this needs to be decided during the surgery itself.
Closed cavity procedures have the advantage of maintaining a normal appearance but have a higher risk of persistent or recurrent cholesteatoma.
In the United States, most surgical procedures for cholesteatoma now are performed through an incision behind the ear combined with an incision in the external auditory canal, but the procedure can be performed through an extended incision starting in the canal alone.
I would recommend that you read the following link for more information
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