Does the chorda tympani nerve confer general sensation from the tongue?

Patients often complain of numbness of the tongue after otologic procedures; this symptom may occur with or without taste alterations. The purpose of this study was to objectively assess possible changes in the general sensation of the tongue in patients undergoing middle ear surgery. Thirty-three individuals were included in this prospective controlled clinical study conducted at a tertiary referral center. Fifteen patients underwent middle ear surgery and 18 volunteers served as a control group. Subjects underwent objective tests to assess general sensation of the tongue before and twice after surgery. Forty-seven percent of the patients complained of numbness or tingling of the tongue shortly after surgery. In these patients, a significant reduction in sensitivities to light touch and 2-point discrimination on the operated side were noted at that time ( P < 0.01; P < 0.009 respectively). Values returned to baseline on subsequent evaluations. No sensitivity change was noted for the contralateral hemi-tongue. Objective changes in the general sensory function of the tongue correlated with post-operative clinical symptoms experienced by patients. The results of this study support the notion that the chorda tympani nerve confers general sensation from the tongue. EBM rating: A-1b