Morphometric analysis of facial and cochlear nerves in normal-hearing ears using 3D-CISS.

PURPOSE: The aim of the current study was to establish a normative data set for the morphometric parameters of the facial nevre (FN) and cochlear nevre (CN) according to age and sex in the adult population, using 3-dimensional constructive interference in steady state (3D-CISS) sequence on magnetic resonance imaging.

METHODS

We retrospectively analyzed 157 ears of 102 adults with no hearing impairment, facial palsy or Ménière's disease. The vertical (VD) and horizontal (HD) diameters as well as cross-sectional areas (CSAs) of the FNs and CNs were measured on the parasagittal oblique image created using the axial 3D-CISS sections passing through the internal acoustic canal. We related the measurement results with side, sex and age.

RESULTS

The mean VD, HD and CSA of the FNs were 1.09 ± 0.18 mm, 0.84 ± 0.17 mm, and 0.75 ± 0.27 mm2, respectively, whereas those of the CNs were 1.34 ± 0.17 mm, 1 ± 0.15 mm and 1.06 ± 0.3 mm2, respectively. There was no statistically significant difference between the morphometric parameters of both the nerves according to side or sex (P > 0.05). However, except for the CSA of the FNs among males, we found a statistically significant decrease in all the morphometric parameters of both the nerves with ageing (P < 0.05).

CONCLUSION

The normative morphometric data obtained in this study can be beneficial in clinical applications for sensorineural hearing loss, facial palsy and Ménière's disease.