Comparative analysis of voice changes after thyroidectomy; mass versus individual ligation of superior thyroid artery with reference to identification of external branch of superior laryngeal nerve

Authors

  • Sunil Samdani Department of ENT and Head and Neck Surgery, SMS Medical College, Jaipur, Rajasthan, India
  • Shweta Dudi Department of ENT and Head and Neck Surgery, SMS Medical College, Jaipur, Rajasthan, India
  • Veena Mobarsa Department of ENT and Head and Neck Surgery, SMS Medical College, Jaipur, Rajasthan, India

DOI:

https://doi.org/10.18203/issn.2454-5929.ijohns20202217

Keywords:

External branch of superior laryngeal nerve, Superior thyroid vessel, Auditory perceptual test, GRBAS scale, Electromyography

Abstract

Background: The external branch of the superior laryngeal nerve innervates the cricothyroid muscle to promote lengthening and thinning of the vocal fold, thus increasing voice pitch. The close relation with the superior thyroid vessels puts the external branch of the superior laryngeal nerve in risk every time the superior pole of the thyroid is dissected.

Methods: : This randomized  controlled  study was undertaken at SMS Medical College, Jaipur between  February  2013 to November 2014  to  evaluate  the  impact  of  isolating  and  ligating  the  superior  thyroid  vessels  near  the  upper pole of the gland as compared  to conventional mass  ligation  of  the  superior  pole  regarding  external branch of superior laryngeal nerve injury in hemi or  subtotal  thyroidectomy. Total 120 patients were taken and divided into two groups A and B. Group A including mass ligation of superior pole of thyroid and group B includes individual ligation of superior thyroid vessels.  

Results: Our study observed normal voice in 51 cases (85%) in individual ligation of superior thyroid vessel group and 27 cases (45%) in mass ligation group on auditory perceptual test by GRBAS scale one month postoperatively. Normal electromyography findings after 1 month post-operatively was observed in 57 cases (95%) in individual ligation group as compared to 40 cases (66.67%) in mass ligation group.

Conclusions: Our study conclude that careful ligation of superior thyroid vessels is a safe technique to preserve the external branch of superior laryngeal nerve than mass ligation of superior pole of thyroid.

References

Jansson S, Tisell LE, Hagne I. Partial superior laryngeal nerve (SLN) lesions before and after thyroid surgery. World J Surg. 1988;12:522-7.

Hast MH. Physiological mechanisms of phonation: Tension of the vocal fold muscle. Acta Otolaryngol. 1966;62:309-18.

Fancy T, Gallagher D, Hornig JD. FRSC(C) Surgical Anatomy of the Thyroid and Parathyroid Glands. Otolaryngol Clin N Am. 2010;43:221-7.

Janfaza P, Nadol JB, Fabian RL. Surgical anatomy of the head and neck. Philadelphia: Lippincott Williams and Wilkins; 2001.

Ozlugedik S, Acar H, Apaydin N. Surgical anatomy of the external branch of the superior laryngeal nerve. Clin Anat. 2007;20:387-91.

Lennquist S, Cahlin C, Smeds S. The superior laryngeal nerve in thyroid surgery. Surgery. 1987;102:999-1008.

Cernea C, Ferraz A, Nishio S. Surgical anatomy of the external branch of the superior laryngeal nerve. Head Neck. 1992;14:380-3.

Morton RP, Whitfield P, Ali AS. Anatomical and surgical considerations of the external branch of the superior laryngeal nerve: a systematic review. Clinical Otolaryngology. 2006;31:368-74.

Aluffi P, Policarpo M, Chevorac C. Post-thyroidectomy superior laryngeal nerve injury. Eur Arch Otorhinolaryngol. 2001;258:451-4.

Stojadinovic A, Shaha A, Orlikoff R. Prospective functional voice assessment in patients undergoing thyroid surgery. Ann Surg. 2002;236(6):823-32.

Koraitim TY, Habashi A, Hammadi E. Voice changes after thyroidectomy; Role of external laryngeal nerve. Bull Alex Med. 2006;42:1.

Kotby MN. Voice disorder: Recent diagnostic advances. Egy J Otolaryngol. 1986;3(1):69.

Hirano M. New York, Clinical Examination of Voice. Springer; 1981: 83-84.

Gregor MAL, Duplessis DJ. A Synopsis of Surgical Anatomy, 10th Ed. Baltimore, Williams and Wilkins Co., 196929 Lennquist S, Cahlin C, Smeds S. The superior laryngeal nerve in thyroid surgery. Surgery. 1987;102(6):999-1007.

Dackiw A, Rotstein L, Clark OH. Computer-assisted evoked electromyography with stimulating surgical instruments recurrent/external laryngeal nerve identification and preservation in thyroid and parathyroid operation. Surgery. 2002;132:1100-8.

Sulica L. The superior laryngeal nerve: function and dysfunction. Otolaryngol Clin N Am. 2004;37:183-201.

Morton RP, Whitfield P, Ali S. Anatomical and surgical considerations of the external branch of the superior laryngeal nerve: a systematic review. Clin Otolaryngol. 2006;31:368-74.

Kochilas X, Bibas A, Xenellis J. Surgical anatomy of the external branch of the superior laryngeal nerve and its clinical significance in head and neck surgery. Clin Anat. 2008;21:99-105.

Teitelbaum BJ, Wenig BL. Superior laryngeal nerve injury from thyroid surgery. Head Neck. 1995;17 (1):36-40.

Kark AE, Kissen MW, Auerbach A, Meikle M. Voice changes after thyroidectomy: role of the external laryngeal nerve. Br M J. 1984;289:1412-5.

Lekacos NL, Miligos ND, Tzardis PJ, Majiatis S, Patoulis J. The superior laryngeal nerve in thyroidectomy. Am Surgeon. 1987;53:610-2.

Saeed EA, Kayyal EA, Baky AS, Ezzat A, Badawi M, Sadi ES, et al. Avoidance of external laryngeal nerve injury during thyroidectomy. Menoufiya Med J. 1995;7(1):115-22.

Guindy EA, Aziz AM. Superior laryngeal nerve preservation in peri-apical surgery by mobilization of the viscerovertebral angle. J Laryngol Otol. 2000;114:268-73.

Downloads

Published

2020-05-22

Issue

Section

Original Research Articles