scholarly journals 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

2020 ◽  
Vol 6 (6) ◽  
pp. 1155
Author(s):  
Sunil Samdani ◽  
Shweta Dudi ◽  
Veena Mobarsa
Keyword(s):  
Superior Laryngeal Nerve ◽  
Close Relation ◽  
Laryngeal Nerve ◽  
Controlled Study ◽  
Superior Thyroid Artery ◽  
Cricothyroid Muscle ◽  
External Branch ◽  
Group B ◽  
The Impact ◽  
Superior Pole

<p class="abstract"><strong>Background:</strong> 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.</p><p class="abstract"><strong>Methods:</strong> : 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.  </p><p class="abstract"><strong>Results:</strong> 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.</p><p class="abstract"><strong>Conclusions:</strong> 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.</p>

scholarly journals Identification and Preservation of External Branch of Superior Laryngeal Nerve in Thyroidectomy

2013 ◽  
Vol 3 (2) ◽  
pp. 39-41 ◽  
Author(s):  
Bhagyashree D Bokare ◽  
Poorva K Athavale ◽  
Vipin R Ekhar ◽  
Devendra Meghraj Mahore
Keyword(s):  
Thyroid Gland ◽  
Total Thyroidectomy ◽  
Superior Laryngeal Nerve ◽  
Vocal Folds ◽  
Laryngeal Nerve ◽  
Superior Thyroid Artery ◽  
Type I ◽  
Care Hospital ◽  
External Branch ◽  
Superior Pole

ABSTRACT The basic principle of head and neck surgery is based on the identification and preservation of important structures, rather than avoidance. This principle is also applicable to identification and preservation of external branch of the superior laryngeal nerve (EBSLN) as a standard routine in all thyroid surgeries. During thyroid surgery, the EBSLN is clearly at risk due to its close proximity to the superior thyroid artery (STA) and its branches that need to be ligated during dissection of the superior pole of the thyroid gland. Injury is detrimental to the patient by causing paralysis of the cricothyroid muscle which is the main tensor and pitch controlling mechanism of the vocal folds. Injury to the EBSLN during surgery can result in the voice changes, loss of upper range and easy fatigability of voice, the severity of which varies according to the vocal demand of the patient. Total 45 cases of thyroid swellings were treated with surgery, in the Department of ENT at a tertiary care hospital during the period from 1st October 2009 to 30th October 2010. Hemithyroidectomy was the most common operative procedure implemented in 24 patients (53.33%) in which right sided was common. Next common procedure performed was that of total thyroidectomy in 14 patients (31.11%). Four patients underwent total thyroidectomy with neck dissection. The position of EBSLN was classified according the Cernea et al classification. In our study we found the EBSLN to be type I in 46.66%, type IIa in 73.33% and type IIb in 02.22%. The anatomical landmark taken into consideration to identify EBSLN was the Joll's triangle with its relation to the superior pole of the thyroid gland and STA. How to cite this article Athavale PK, Bokare BD, Ekhar VR, Mahore DM. Identification and Preservation of External Branch of Superior Laryngeal Nerve in Thyroidectomy. Int J Phonosurg Laryngol 2013;3(2):39-41.

scholarly journals Assessment of Relation between External Branch of Superior Laryngeal Nerve & Thyroid Gland- A Cadaveric Study

2020 ◽  
Vol 6 (2) ◽  
pp. 73-76
Author(s):  
Anurag ◽  
Vishnu Gupta
Keyword(s):  
Thyroid Gland ◽  
Cricoid Cartilage ◽  
Superior Laryngeal Nerve ◽  
Laryngeal Nerve ◽  
The Body ◽  
Superior Thyroid Artery ◽  
Group I ◽  
External Branch ◽  
The Mean ◽  
Group Ii

Background: The thyroid gland is essential for normal growth of the body. This study assessed relation of external branch of superior laryngeal nerve to the superior pole of the thyroid gland. Subjects and Methods: This study was conducted on 25 human cadavers having 50 superior thyroid poles of both genders. Cadavers were classified based on age groups, group I was those with age less than 39 years and group II cadavers were those with age more than 40 years of age. Various measurements were performed on cadavers. Results: 14 cadavers were I group I and 11 were in group II. The mean mass was 67.2 Kgs in group I and 59.5 Kgs in group II, time elapsed after death was 481.5 minutes in group I and 476.4 minutes in group II, mean height was 1.74 meters in group I and 1.69 meters in group II, mean BMI found to be 22.3 kg/m2in group I and 20.1 kg/m2in group II. Height found to be significant between both groups (P< 0.05). The mean distance from EBSLN to cranial point of the thyroid gland was 6.66 mm in group I and 8.96 mm in group II. The mean transverse distance from superior thyroid artery to EBSLN was 3.55 mm in group I and 5.12 mm side in group II. The mean distance of the crossing point between the most cranial point of the thyroid lobe was 6.40 mm in group I and 11.47 mm in group II. The mean distance from the EBSLN to the midline of the neck was 19.80 mm in group I and 18.58 mm in group II. The mean distance from the EBSLN to the midline of the neck on the most cranial point of the cricoid cartilage was 18.77 mm in group I and 17.80 mm in group II. Conclusion: Authors found variation in measurements in left and right side in both group I and group II.

Microsurgical Anatomy of the Superior and Recurrent Laryngeal Nerves

Neurosurgery ◽  
2001 ◽  
Vol 49 (4) ◽  
pp. 925-933 ◽  
Author(s):  
Ashkan Monfared ◽  
Daniel Kim ◽  
Sivakumar Jaikumar ◽  
Goutham Gorti ◽  
Andrew Kam
Keyword(s):  
Superior Laryngeal Nerve ◽  
Laryngeal Nerve ◽  
Superior Thyroid Artery ◽  
Microsurgical Anatomy ◽  
Anatomic Landmarks ◽  
Internal Branch ◽  
Cricothyroid Muscle ◽  
Thyrohyoid Membrane ◽  
Recurrent Laryngeal Nerves ◽  
The Right

Abstract OBJECTIVE To study the microsurgical anatomy of the superior laryngeal nerve (SLN) and recurrent laryngeal nerve (RLN) with respect to anatomic landmarks, and to identify their vascular supplies. METHODS The microsurgical anatomy of the anterior neck, the course of the right and left SLN and RLN and their variations were studied in 21 cadavers. Fresh cadavers were perfused with colored silicon dye to investigate the microvasculature in detail. RESULTS SLN originates from the inferior vagal ganglion at the C2 level and descends medially toward the thyrohyoid membrane. It branches into an external and an internal branch deep to the internal carotid artery at the C3 level. The external branch, along with the cricothyroid artery, descends deep to the superior thyroid artery toward the cricothyroid muscle. Accompanied by the superior laryngeal artery, the internal branch passes deep to the loop of the superior thyroid artery and pierces the thyrohyoid membrane. Both nerves reside in the fascia covering longus colli muscles and are supplied by their accompanying arteries. The loop of RLN is found at the T1–T3 level on the right, and more caudally at the T3–T6 level on the left, entering the larynx between C5–C7 levels on both sides. RLN receives arterial supply from the esophageal and tracheal branches of the inferior thyroid artery proximally, and by the inferior laryngeal artery distally. CONCLUSION Incidental intraoperative injury to the SLN and RLN potentially could be avoided by understanding the detailed course of each nerve with respect to the surrounding anatomic landmarks and by recognizing their blood supplies.

scholarly journals Can we routinely identify the external branch of the superior laryngeal nerves with neural monitoring?: a prospective report on 176 consecutive nerves at risk

2021 ◽  
Author(s):  
Paolo Del Rio ◽  
Elena Bonati ◽  
Tommaso Loderer ◽  
Matteo Rossini ◽  
Federico Cozzani
Keyword(s):  
Voice Quality ◽  
Superior Laryngeal Nerve ◽  
Laryngeal Nerve ◽  
Muscle Twitch ◽  
Cricothyroid Muscle ◽  
Emg Signal ◽  
External Branch ◽  
Mode Of Application ◽  
Neural Monitoring ◽  
Intermittent Mode

AbstractThe external branch of the superior laryngeal nerve (EBSLN) provides motor function to the cricothyroid muscle (CTM). EBSLN damage produces changes in voice quality and projection. Intraoperative neuromonitoring (IONM) in thyroid surgery aims to optimize EBSLN control during dissection. We prospectively collected the data of 88 consecutive patients who underwent total thyroidectomy with IONM from July 2019 to December 2019. IONM was offered in the intermittent mode of application. We routinely searched for the EBSLN electromyographic (EMG) signal before (S1) and after (S2) dissection of the superior vascular peduncle. In the absence of the EMG signal, we observed the CTM twitch. We identified 141 (80%) S1 EMG signals, while we recorded the CTM twitch in 15 cases (8.5%). In 20 (11.3%) cases, we were unable to identify the EMG signal. Analysing the S2 results, we found loss of EBSLN signal in 11/141 cases (7.8%) identified with IONM in pre-dissection stimulation. Among the 20 cases without pre-dissection identification (we had not identified the external branch of the superior laryngeal nerve or the muscle twitch), in the post-dissection evaluation, we confirmed the loss of signal in 17 of 20 cases, equal to 85% (p < 0.001). Our data clearly show that intraoperative stimulation and recognition of EBSLN, performed before any dissection manoeuvre to the superior vascular thyroid pole, leads to a much higher rate of nerve conservation.

scholarly journals Relation of the external branch of the superior laryngeal nerve to the superior pole of the thyroid gland: An anatomical study

2007 ◽  
Vol 20 (5) ◽  
pp. 516-520 ◽  
Author(s):  
D. Naidoo ◽  
J.M. Boon ◽  
C.J. Mieny ◽  
P.J. Becker ◽  
A.-N. van Schoor
Keyword(s):  
Thyroid Gland ◽  
Superior Laryngeal Nerve ◽  
Anatomical Study ◽  
Laryngeal Nerve ◽  
External Branch ◽  
Superior Pole

External Branch of the Superior Laryngeal Nerve: Applied Surgical Anatomy and Implications in Thyroid Surgery

2012 ◽  
Vol 78 (9) ◽  
pp. 986-991 ◽  
Author(s):  
George H. Sakorafas ◽  
Panayiotis Kokoropoulos ◽  
Christos Lappas ◽  
Dimitrios Sampanis ◽  
Vassilios Smyrniotis
Keyword(s):  
Thyroid Surgery ◽  
Full Range ◽  
Superior Laryngeal Nerve ◽  
Surgical Anatomy ◽  
Laryngeal Nerve ◽  
Injury Incidence ◽  
High Frequencies ◽  
Cricothyroid Muscle ◽  
External Branch ◽  
Operating Surgeon

The external branch of the superior laryngeal nerve (EBSLN) is the only motor supply to the cricothyroid muscle and has an important role during phonation in high frequencies. Iatrogenic injury of the EBSLN, most commonly during thyroid surgery, is associated with varying levels of alterations in phonation, which may have an impact on a patient's life, especially when his or her career depends on the full range of voice. EBSLN injury incidence after thyroid surgery ranges widely in the literature (0 to 58%). Despite this wide variation, it appears that EBSLN injury is a not uncommon, and frequently overlooked, complication of thyroid surgery. An in-depth knowledge of the surgical anatomy of the EBSLN is therefore required from the part of the operating surgeon to protect this nerve during thyroid surgery.

scholarly journals Identification of external branch of superior laryngeal nerve during thyroid surgery: a prospective study

2017 ◽  
Vol 4 (1) ◽  
pp. 228 ◽  
Author(s):  
Vipin R. Ekhar ◽  
Ramkumar V. ◽  
Ritesh N. Shelkar ◽  
Akshay V. Sarode
Keyword(s):  
Thyroid Surgery ◽  
Tertiary Care ◽  
Surgical Techniques ◽  
Superior Laryngeal Nerve ◽  
Laryngeal Nerve ◽  
Individual Identification ◽  
Care Hospital ◽  
External Branch ◽  
A Prospective Study ◽  
Superior Pole

<p class="abstract"><strong>Background:</strong> Identification of external branch of superior laryngeal nerve (EBSLN) according to Cernea et al classification and to describe a surgical technique of superior pole dissection to preserve EBSLN during thyroid surgeries.</p><p class="abstract"><strong>Methods:</strong> The study was done over 2 years period in a tertiary care hospital. 105 nerves were studied among the 90 patients who underwent thyroid surgeries. Avascular dissection over the JOLL’S triangle was carried out and identified EBSLN were classified according to Cernea et al classification. Individual ligation of superior pole vessels was carried out after identifying the nerve. Outcome was studied relating the identified nerve with sides of thyroidectomy performed, size of thyroid gland and nerves at risk according to Cernea et al classification.  </p><p class="abstract"><strong>Results:</strong> Of the 105 nerves studied, in 81.90% of patients the nerve was identified. There were 34.88% of Type 1 nerves, 52.33% of Type 2A nerve and 12.79% of Type 2B nerves identified. Less number of nerves could be identified on the left side. Type 2B nerves were more common on left side inspite of less number of dissections carried out on left. Type 2 variation was more common in large goiters.</p><p><strong>Conclusions:</strong> Careful dissection should be done in superior pole in avascular cricothyroid space, with lateralization of superior pole and individual identification of superior pole vessels once the nerve is identified. Identification of the nerve is mandatory in all patients who undergo thyroid surgery for optimal functions of the larynx. These results showed a better identification of nerves by proper surgical techniques without use of any sophisticated equipments. </p>

Sign in / Sign up

Export Citation Format

Share Document