Innervation of Human Cricopharyngeal Muscle By Recurrent Laryngeal and External Branch of Superior Laryngeal Nerve

Sisli Hamidiye Etfal Training and Research Hospital

Status: Completed

Conditions: Larynx

Treatments: Device: The NIM 3.0 Nerve Monitoring System

Study type: Interventional

Funder types: Other

Identifiers

NCT02761239

SEEAH02

Details and patient eligibility

About

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).

Full 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.

Enrollment: 100 patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Basic Science

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

---

100 participants in 1 patient group

Cricopharyngeal muscle innervation

Other group

Description:

The recurrent laryngeal nerve (RLN), vagus nerve, external branch of the superior laryngeal nerve (EBSLN) and pharyngeal plexus were stimulated intraoperatively by the NIM 3.0 Nerve Monitoring System (Medtronic Xomed, Jacksonville, FL, USA). Responses were evaluated by visual observation of the cricopharyngeal muscle and electromyographies via needle electrodes inserted into the cricopharyngeal muscle.

Treatment:

Device: The NIM 3.0 Nerve Monitoring System