[Morphological and morphometric study of the tympanic and mastoid portions of the fallopian aqueduct].

In surgery of the temporal bone the best way to avoid injuries to the facial nerve is to be acquainted with its location in all the surgical steps of the procedure scheduled. That is to say: an exact knowledge of its normal intratemporal run, having always in mind some characteristic landmarks, is absolutely essential. This work has been done through drilling 92 human temporal bones, measuring the length of both the tympanic and mastoidal segments and also considering the bending of the 2nd knee of the nerve. In the issue the mastoidal portion resulted the most straight (by half of the cases) whereas the tympanic one was slightly sloping downwards between the lateral semicircular canal upwards and the oval window below. Topographically has not been possible to establish neither a strict correlation between the location of the pyramide and the 2nd knee nor this knee was found by uns (in contrast to other AA's findings) at higher angle than 90 degrees in our specimen.