Multidirectional tomagraphy of defects in the facial canal. An experimental investigation

Defects on the tympanic wall of the facial canal may endanger the nerve in middle ear surgery. Their preoperative tomographic demonstration is therefore valuable. In an experimental investigation an attempt was made to assess the discernibility of artificial defects of different size by hypocycloid and spiral tomography of temporal bone specimens (both isolated and mounted in a tissue-equivalent skull phantom). The thickness of the wall was measured and its influence on the discernibility of the defects discussed.