The effects of the chorda tympani damage on submandibular glands: biometric changes

It was aimed to analyze the biometric changes in ipsilateral submandibular glands of patients with unilateral chorda tympani (ChT) section during otological operations, compared with change in size of the contralateral glands and with those of healthy subjects.

29 patients with unilateral complete ChT section and 29 healthy subjects with identical ages, genders, and weights to the patient group were examined ultrasonographically. The patients having a mean duration to follow-up examination of 32 months (2-84 months) were subdivided into two groups by their time to follow-up as short-term patient group (2-12 months, 14 patients) and long-term patient group (13-84 months, 15 patients). The ultrasonographic dimensions and volumes of submandibular glands were compared statistically between the groups.

In the patient group, the glands on the contralateral, non-operated side were found to be greater than the ipsilateral, denervated glands in terms of both paramandibular depth dimension (P<0.05) and volume (P<0.01). The differences could be determined only in long-term patient group. When comparing the submandibular glands of the patient group with those of the control group, it was found that paramandibular depth dimension and volume of the submandibular glands on the contralateral, non-operated side were statistically greater (P<0.01). There was no difference between submandibular glands on the operated side of the patient group and those of the control group (P>0.05).

The late (13-84 months) biometric results of ChT damage on submandibular gland were significant for increase in the size of the contralateral, non-denervated submandibular gland. An atrophying effect was not ascertained in the submandibular glands denervated parasympathetically due to the section of the ChT.