Multidirectional tomography in otospongiosis.

Eight clinical situations are best examined by polytomography, namely, ossicular chain disruption, malleus fixation, assessing the extent of footplate fixation, delineating cochlear otospongiosis, postoperative studies of unsuccessful cases, developing an anatomic map preoperatively with particular reference to the intratympanic course of the facial nerve, ruling in or out the rare closure of the round window by otospongiosis, and differentiation of the congenital footplate fixation from true otospongiosis. We discuss each of these situations briefly.