Learning objectives: Complete drill out of all granulations and prevention of adhesions with silicone sheating of mucosa can reduce the risk of cholesteatoma recurrence.

Introduction: Theories on retraction pocket pathogenesis lack convincing proof. A new concept interprets the mysterious ingrowth of skin as a basic principle of healing as seen in other regions of the body.

Methods: Retrospective analysis of the interrelation of retraction pockets and underlying granulation tissue in 253 cholesteatoma revision surgeries in the last decade. Literature research on pathogenesis of cholesteatoma.

Results: Self-cleaning retraction pockets over non-inflamed mucosa remained stable. A retraction did not develop over well-aerated areas with unimpeded mucosal drainage. A new retraction was always contacted active granulation, which had either persisted or emanated from a former cholesteatoma surgery. Findings from experimental and clinical data in literature are in agreement with this new concept.

Conclusions: The pathogenesis of a retraction is interpreted as a natural attempt of the body to cure an underlying inflammation in a cavity. Analogue phenomena exist e.g. in the migration of the omentum towards a local inflammation in the abdomen. Based on this pathomechanism, the prophylaxis against a recurrent cholesteatoma therefore should combine a meticulous cleaning of all pneumatic cells from infectious granulation and establish a free drainage of all cavities of the middle ear into the tubal orifice, avoiding a blockage on the path of mucosal clearance. Rhinosurgery also insists on an unblocked drainage of the operated sinus. In cholesteatoma surgery, thin silicone foils should cover all non-mucosa-coated surfaces behind the tympanic membrane and also in the epitympanon and, if necessary, reaching back to the antrum, ending on the mucosa of the tubal entrance. Gas production of the healthy middle ear mucosa can recover, and the risk of a recurrent retraction is reduced.