The topographical anatomy of the external branch of the süperior laryngeal nerve and its importance in thyroid surgery: a cadaver study

Year 2003, Volume: 11 Issue: 6, 161 - 165, 24.12.2003

Zeynep Alkan Hüseyin Seven Burak Ömür Çakır Berna Uslu Coşkun Suat Turgut Bülent Şam

Abstract

Objectives: We investigated topographical anatomic features of the external branch of the süperior laryngeal nerve SLN in relation to the süperior thyroid artery STA and its vuİnerability to injury in individuals with a normal thyroid size.Study Design: Thirty fresh cadavers 18 females, 12 males; age range 20 to 50 years with normal thyroid size and no signs of abnormality in the neck were studied. The external branch of the SLN was identified and classified according to system proposed by Cernea et al.Results: The topographical relationship betvveen the external branch of the SLN, the STA, and the upper pole of the thyroid gland was identified in 54 thyroid lobes 90% . Identification was not possible in six lobes because of bleeding or injury.The location of the external branch of the SLN was consistent with type 1 in 28 lobes 51.8% and type 2 in 26 lobes 48.2%; type 2a in 37.1% and type 2b in 11.1% . No significant relationships existed betvveen the type of the nerve, gender, and age, nor was there any symmetry with regard to the location of the external branch of the SLN in the same subject.Conclusion: Nearly half of the Turkish population with a normal thyroid gland size present high surgical risks during thyroid surgery because of the course of the external branch of the SLN.

Keywords

Cadaver, laryngeal nerves/injuries/anatomy & histology, neck/surgery, thyroidectomy

Süperior larenjeal sinirin eksternal dalının topografik anatomisi ve tiroit cerrahisindeki önemi: Kadavra çalışması

Abstract

Amaç : Normal boyutlarda tiroit bezine sahip kiflilerde sü- perior larenjeal sinirin SLS eksternal dalının süperior ti- roit arter ile iliflkili olarak topografik anatomik özellikleri ve sinirin hasar görme riski arafltırıldı. Çalıflma Planı: Normal boyutta tiroit bezi olan ve boyun- da herhangi bir anomali belirtisi olmayan 30 taze kadavra çalıflmaya alındı. Süperior larenjeal sinirin eksternal dalı ortaya kondu ve Cernea ve ark.nın tanımlamasına göre sınıflandırıldı. Bulgular: Süperior larenjeal sinirin eksternal dalı, s ü p e r i- or tiroit arter ve tiroit üst kutbu arasındaki topografik iliflki 60 tiroid lobunun 54’ünde %90 ortaya kondu. Altı tiroid lobu, kanama ve travma gibi nedenlerle sinir belirleneme- diğinden çalıflma dıflında bırakıldı. Süperior larenjeal sini- rin eksternal dalının yerleflimi 28 tiroit lobunda %51.8 tip 1, 26’sında %48.2 tip 2 %37.1 tip 2a, %11.1 tip 2b özel- lik gösterdi. Sinir tipleri ile cinsiyet ya da yafl arasında an- lamlı iliflki kurulamadı. Aynı kadavranın iki tarafı arasında sinir yerleflimi yönünden simetri saptanmadı. Sonuç: Ülkemizde normal boyutlarda tiroit bezine sahip kiflilerin yaklaflık yarısının SLS eksternal dalının seyri açı- sından cerrahi sırasında yüksek hasar riskine sahip olduğu sonucuna varıldı

Keywords

Kadavra, larenjeal sinirler/yaralanma/anatomive histoloji, boyun/cerrahi, tiroidektomi

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