EVALUATION OF SUPERIOR LARYNGEAL NERVE FUNCTION AFTER RADIOTHERAPY IN NASOPHARYNX CARCINOMA BY LARYNGEAL ELECTROMYOGRAPHY
1Sağlık Bilimleri Üniversitesi, Kulak Burun Boğaz, İstanbul, Türkiye2Yeni Yüzyıl Üniversitesi, Kulak Burun Boğaz, İstanbul, Türkiye
3Sağlık Bilimleri Üniversitesi, Kulak Burun Boğaz, İstanbul, Türkiye Aim: We aimed to investigate the long-term effects of radiotherapy on superior laryngeal nerve functions in patients receiving radiotherapy in nasopharynx carcinoma by laryngeal electromyography.
Method and Materials: Forty-one patients who received radiotherapy for nasopharyngeal carcinoma were included in the study. Vocal cord movements and mucosa were assessed by endoscopic examination before performing laryngeal electromyography (L-EMG). Crichothyroid muscle functions were studied using 26 G concentric needle electrodes. As control group, 50 volunteers with no intervention in head and neck region were used. The results of both groups were compared statistically.
Results: Of the 41 patients in the study group, 28 ( % 68 ) were male, 13 ( % 31 ) were female. The age range was between 15 and 65, with a mean age of 40.20. Of the 50 patients in the control group, 34 ( % 68 ) were male and 16( % 32 ) were female. The age range was between 18 and 55 years and the mean age was 41.44. Patients in the study group received daily 1.6-2.2 Gy fractional radiotherapy and the total maximum dose was 50-70 Gy. Entry activities were normal in all patients and control group, normal motor unit potentials were recorded in voluntary contractions, and adequate interfer- ence activity was obtained in maximal contraction. There was no statistically significant difference between the two groups in terms of nerve time, amplitude and latency parameters.
Conclusion: Radiotherapy for nasopharyngeal carcinoma seems not to cause superior laryngeal nerve dysfunction, but larger patient series are needed to confirm this.
Keywords : Superior laryngeal nevre, Electromyography, Radiotherapy, nasopharynx carcinoma