Clinical trial NCT02761239: Innervation of Human Cricopharyngeal Muscle By Recurrent Laryngeal and External Branch of Superior Laryngeal Nerve
Official title: Descriptive In Vivo Study of Evaluating the Innervation of The Human Cricopharyngeal Muscle By The Recurrent Laryngeal Nerve and External Branch of The Superior Laryngeal Nerve
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Larynx
Keywords: cricopharyngeal muscle
innervation by EBSLN
A prospective case-controlled study
Lead sponsor: Sisli Hamidiye Etfal Training and Research Hospital
Sponsor class: OTHER
First posted: 2016-05-04
Enrollment: 100
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

Brief summary: The investigators hypothesized that, external branch of the superior laryngeal nerve (EBSLN) and/or recurrent laryngeal nerve (RLN) contribute to the motor function of the human cricopharyngeal muscle (CP). The investigators aimed to assess the contribution of the laryngeal nerves (EBSLN and RLN) to the motor activity of the cricopharyngeal muscle, during thyroidectomy with intraoperative neuromonitoring (IONM).

Detailed description: This study group consisted of a consecutive patients undergoing thyroid surgery with intraoperative neuromonitoring (NIM 3.0 Nerve Monitoring Systeme (Medtronic Xomed, Jacksonville, FL, USA) ) for various diseases. In all patients, each side of the neck operated was considered as a separate entity in our study.

EMG recordings were accomplished with a pair of needle electrodes inserted into the CP and mid-portion of the CT muscle that is located on the superior side of the RLN, which were plugged into the third and fourth channels of interface-connector box, respectively, at the end of the thyroidectomy or lobectomy. The investigators evaluated the innervation pattern of the CT muscle in an other study. Therefore the EBSLN is the main supplier of the CT muscle, the EMG findings of the CT muscle were used to confirm it, in this study.

EBSLN, pharyngeal plexus (PP), RLN and vagus nerve were stimulated with a monopolar stimulator probe at 1 mA. While stimulating these nerves, the ipsilateral CP muscle was visually observed for possible contractions and electromyographic recordings were obtained with the 4-channel NIM 3.0 Nerve Monitoring System.

Eligibility criteria: Inclusion Criteria:

* The patients who underwent thyroidectomy.

Exclusion Criteria:

* Preoperative RLN palsy
* Thyroid cancer with massive extrathyroidal extension
* Intentional nerve transection because of cancer invasion
* The assessment failure of nerve function due to the technical deficiency of the IONM equipment

Primary outcomes:
measure: The cricopharyngeal muscle innervation pattern that is evaluated by visual contractions and EMG evoked potentials, with stimulation of the nerves
timeFrame: up to 9 months
Secondary outcomes:
measure: The comparison of the EMG amplitudes obtained with the stimulation of the recurrent laryngeal nerve (RLN), vagus nerve, external branch of the superior laryngeal nerve (EBSLN) and pharyngeal plexus.
timeFrame: up to 9 months
Other outcomes:
Locations:
Study officials:
affiliation: Sisli Etfal Training and Research Hospital
name: Mehmet Uludag, Professor
role: STUDY_DIRECTOR
References:
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