Variations in Length of Facial Nerve in the Segments of Temporal Bone of Male Cadavers in South Indian Region

In the present study facial nerve was dissected in 25 male temporal bones. The length of facial nerve in different segments of temporal bone was measured. In petrosal segment the mean length of facial nerve was 7.82 mm ± 0.27(SD=1.32). In labyrinthine segment mean length was 3.4mm ± 0.9(SD=0.45). In tympanic segment mean length was 12.13mm ± 0.7(SD=0.35). In mastoid segment it was 12.24mm ± 0.38(SD=1.90). The mean length of nerve to stapedius was 15.71mm ± 0.13 (SD=0.63) and mean length of chordatympani nerve was 19.01mm ± 0.17(SD=0.82). (These both nerves had measured from geniculate ganglia). The present values varied with previous workers in some segments and agreed in some segments of temporal bone. Hence these values had regional or racial significance could be due to biological variation or outcome of hybridized race but important for clinician, radiologist and mainly for Otosurgoen to anticipate the position of facial nerve to avoid its injury.