Surface contour three-dimensional imaging in congenital aural atresia.

Sixty-five patients with congenital aural atresia-stenosis had three-dimensional reconstructions of their high-resolution computed tomographic scans. Surface anatomy of the temporal bone was readily demonstrated, including its relation to the temporomandibular joint. Three important findings were noted. (1) Contrary to popular belief, the condyle of the mandible does not rest against the anterior face of the mastoid bone. (2) A bony cleft or groove is often in the lateral temporal bone through which the facial nerve may exit. (3) Duplications of bony structures attached to or part of the temporal bone are clearly defined. The information gained from the routine use of three-dimensional imaging of the computed tomographic scan alerts us to potential intraoperative problems that may otherwise escape our scrutiny, particularly if only two-dimensional computed tomographic scanning is done.