Distance between Anterior Commissure and the First Tracheal Ring: An Important New Clinical Laryngotracheal Measurement

Khadivi, Ehsan; Zarringhalam, Mohammad Ali; Khazaeni, Kamran; Bakhshaee, Mehdi

doi:10.22038/ijorl.2015.4252

Distance between Anterior Commissure and the First Tracheal Ring: An Important New Clinical Laryngotracheal Measurement

Document Type : Original

Authors

Ehsan Khadivi ¹

Mohammad Ali Zarringhalam ²

Kamran Khazaeni ²

Mehdi Bakhshaee ¹

¹ Sinus and Surgical Endoscopic Research Center, Ghaem Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

² Department of Otorhinolaryngology-Head & Neck Surgery, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

10.22038/ijorl.2015.4252

Abstract

Introduction:
The distance between the anterior commissure of the larynx and the first tracheal ring (AC.T. distance) is of great importance in laryngotracheal surgeries. The amount of narrowing of the subglottic airway is used as a quantitative mean to determine whether the lesion is subglottic or has extended to the trachea and therefore helps in the prediction of the final prognosis.

Materials and Methods:
In this study, the larynx was exposed by direct laryngoscopy under general anesthesia. The case was considered to be difficult because the exposure did not optimally reveal the anterior commissure, therefore a cricoid tape or anterior commissure laryngoscope was used. A zero degree Hopkins lens was used to view the anterior commissure and the first tracheal ring. Special markers were used to mark the two points with the distance between those being considered as the AC.T. distance. The relationship between AC.T. distance and the patient's age, sex, BMI, and laryngeal exposure condition during laryngoscopy was also studied.

Results:
Eighty-two patients participated in this study. The mean AC.T. distance was measured and was found to be 32.67±3.34 mm in males and 29.80± 3.00 mm in females. This difference was statistically significant between the two groups (P<0.05). There was no statistically significant relationship between BMI, age, laryngeal exposure condition, and the AC.T. distance.

Conclusion:
The AC.T. distance was measured to be around 3 cm; with males measuring greater than females. However, future studies may lead to a more accurate practical scale for laryngotracheal surgeries due to possible technical or human errors, in addition to racial differences.

Keywords

Airway stenosis

Anterior commissure

BMI

Subglottic

Trachea

Vocal cord

Subjects

1. Cotton RT, Gray SD, Miller RP. Update of the Cincinnati experience in laryngotracheal reconstruction. Laryngoscope 1989; 99(11):1111-6.pe

2.Alvarez-Neri H, Penchyna-Grub J, Porras-Hernandez JD, Blanco-Rodriguez G, Gonzalez R, Rutter MJ.Primary cricotracheal resection with thyrotracheal anastomosis for the treatment of severe subglottic stenosis in children and adolescents. Ann Otol Rhinol Laryngol 2005 Jan; 114(1):2-6.

3. Standring S. Gray’s Anatomy. Churchill Livingstone: Elsevier, 2004.

4. Couch ME. History, Physical Examination, and the Preoperative Evaluation. In: Flint PW, Haughey BH, Lund VJ, Niparko JK, Richardson MA, Robbins KT, Thomas JR, editors. Cummings Otolaryngology- Head and Neck Surgery, 5^th ed. Philadelphia:ElsevierMosby; 2010. P. 99.

5. Philippe Monnier. Subglottic and Tracheal Stenosis. In: Remacle M, Echel HE, editors. Surgery of larynx and Trachea. 1^st ed. Berlin, Heidelberg, Springer; 2010. P. 155-6.

6.Khalid AN, Goldenberg D. Surgical Management of Upper Airway Stenosis. In: Flint PW, Haughey BH, Lund VJ, Niparko JK, Richardson MA, Robbins KT, Thomas JR, editors. Cummings Otolaryngology- Head and Neck Surgery, 5^thed. Mosby; 2010. P. 943-52.

7. Friedrich G, Lichtenegger R. Surgical anatomy of the larynx. J Voice 1997 Sep; 11: 345-55.

8. Kim WH, Ahn HJ, Lee CJ, Shin BS, Ko JS, Choi SJ, et al. Neck circumference to thyromental distance ratio: a new predictor of difficult intubation in obese patients. British Journal of Anaesthesia 2011; 106: 743–8.

9. Brodsky JB, Lemmens HJ, Brock-Utne JG, Vierra M, Saidman LJ. Morbid obesity and tracheal intubation. Anesth Analg. 2002 Mar; 94: 732-6.

10. Lundstrom LH, Moller AM, Rosenstock C, Astrup G, Wetterslev J. High body mass index is a weak predictor for difficult and failed tracheal intubation: a cohort study of 91,332 consecutive patients scheduled for direct laryngoscopy registered in the Danish Anesthesia Database. Anesthesiology. 2009 Feb; 110:266-74.

11. Hiramooto M.Functinal anatomy of the larynx. In: Isshiki N. Phonosurgery. 1^st ed. Tokyo: Springer; 1989.

12. Isshiki N. Phonosurgery. 1^st ed. Tokyo: Springer, 1989.

13. Lundstrøm LH, Møller AM, Rosenstock C, Astrup G, Wetterslev J. High body mass index is a weak predictor for difficult and failed tracheal intubation: a cohort study of 91,332 consecutive patients scheduled for direct laryngoscopy registered in the Danish Anesthesia Database. Anesthesiology 2009; 110:266-74.

14. Juvin P, Lavaut E, Dupont H, Lefevre P, Demetriou M, Dumoulin JL, et al . Difficult tracheal

intubation is more common in obese than in lean patients. Anesth Analg 2003; 97(2):595-600.

15. Lavi R, Segal D, Ziser A. Predicting difficult airways using the intubation difficulty scale: a study comparing obese and non-obese patients. J Clin Anesth 2009; 21:264.

16. Brodsky JB, Lemmens HJ, Brock-Utne JG, Vierra M, Saidman LJ. Morbid obesity and tracheal intubation. Anesth Analg 2002; 94(3):732-6.