The Tensor Tympani Tendon: A Hypothetical Site of Origin of Congenital Cholesteatoma.

Multiple theories have been discussed about the etiopathogenesis of congenital middle ear cholesteatoma (CMEC) and its specific site of origin. The intraoperative identification of the precise location of the keratinous mass is important to guarantee its complete removal, in order to reduce the risk of recurrence. This study proposes the tensor tympani tendon (TTT) as a possible site of origin of CMEC. All CMECs treated between 2013 and 2019 were reviewed. Only Potsic stage I lesions were included. Preoperative radiologic images were compared to intraoperative findings. Three removed TTT were sent for histologic evaluation. Seven patients were included (M:F = 3:4). Preoperative CT images were classified as type A in 2 cases (28.6%) and type B in 5 cases (71.4%). At intraoperative evaluation all CMEC sacs were found pedunculated on the TTT. The histologic examinations confirmed the connection between the cholesteatomatous sac and the TTT. According to the correlation of imaging, intraoperative findings and histology, we proposed that the TTT could be the primary site from which CMEC originates.