Prevention of non-recurrent laryngeal nerve injury in robotic thyroidectomy: imaging and technique

Non-recurrent right laryngeal nerve identified during endoscopic thyroidectomy via areolar approach: a case report

Background

Nonrecurrent laryngeal nerve (NRLN) is a rare but significant anatomical variation in thyroid surgery, and lack of awareness of NRLN may lead to intraoperative injury. Here, we report a clinical case of NRLN discovered during endoscopic thyroid surgery via total areola approach in a 23-year-old female patient.

Case presentation

A 23-year-old female patient presented with bilateral thyroid nodules for three years. She underwent bilateral thyroid nodule fine-needle aspiration biopsy and BRAF gene testing at our hospital, with results indicating bilateral papillary thyroid carcinoma and positive BRAF gene V600E mutation. Neck-enhanced CT revealed bilateral thyroid nodules and the right subclavian artery branching from the aortic arch on the distal side of the left subclavian artery. The patient underwent endoscopic thyroidectomy via total areola approach for radical resection of bilateral thyroid cancer. Intraoperatively, NRLN was found on the right side and RLN on the left side. The surgery was successful, and no postoperative complications were observed. Postoperative pathology confirmed bilateral papillary thyroid carcinoma.

Conclusions

Although NRLN is a rare occurrence, clinicians should not overlook its presence to prevent serious complications. Preoperative imaging confirmation of the presence or absence of an abnormal subclavian artery course is crucial in preventing the sudden discovery of NRLN during surgery. Endoscopic thyroid surgery via total areola approach is a safe and effective technique but requires a high level of professional skills and an understanding of anatomical variations to prevent nerve injury.

Modern Surgical Techniques of Thyroidectomy and Advances in the Prevention and Treatment of Perioperative Complications

Thyroid cancer is the most common cancer of the endocrine system, and, in recent years, there has been a phenomenon of overdiagnosis followed by subsequent overtreatment. This results in an increasing number of thyroidectomy complications being faced in clinical practice. In this paper, we present the current state of knowledge and the latest findings in the fields of modern surgical techniques, thermal ablation, the identification and assessment of parathyroid function, recurrent laryngeal nerve monitoring and treatment and perioperative bleeding. We reviewed 485 papers, from which we selected 125 papers that are the most relevant. The main merit of this article is its comprehensive view of the subject under discussion-both general, concerning the selection of the appropriate method of surgery, and particular, concerning the selection of the appropriate method of prevention or treatment of selected perioperative complications.

Preservation of the nonrecurrent laryngeal nerve using intraoperative nerve monitoring during endoscopic thyroidectomy

A 40-year-old woman underwent right lobe thyroidectomy for thyroid nodules that increased in size from 17 mm to 33.5 mm within 1 year. Identification of arteria lusoria using computed tomography suggested the presence of a right nonrecurrent laryngeal nerve (RNRLN). Endoscopic thyroidectomy was performed under general anesthesia. The right vagal nerve was first identified between the common carotid artery and jugular vein. A positive response was confirmed via intraoperative neuromonitoring (IONM), implying that the RNRLN did not branch from the central side of the stimulated point of the vagal nerve. The RNRLN was confirmed using IONM around the middle to lower pole of the right thyroid gland. The right thyroid lobe was successfully removed, with meticulous preservation of the RNRLN. The motion of the vocal cord, examined by an ear-nose-throat doctor postoperatively, was intact. We demonstrated the efficacy of IONM in patients with RNRLN who underwent endoscopic thyroidectomy.

Abu Dhabi Neural Mapping (ADNM) during Minimally Invasive Thyroidectomy Enables the Early Identification of Non-Recurrent Laryngeal Nerve and Prevents Voice Dysfunction

The aim of this study was to evaluate the diagnostic accuracy of a neuromonitoring protocol—the Abu Dhabi Neural Mapping protocol (ADNM)—using a new device, Nim-Vital™, during minimally invasive thyroidectomy in the early identification of non-recurrent laryngeal nerve (n-RLN) problems and the preservation of its function. Method: Patients with thyroid disorders that required thyroid resection, who were admitted to the Department of Surgery at Burjeel Hospital, Abu Dhabi, between January and July 2022, were included in the study. The data were extracted from a prospective database and were analyzed retrospectively. All nerves at risk were identified and exposed at seven precisely defined anatomical points, with strict adherence to the intraoperative technical steps of neuromonitoring. These were sequentially applied to the vagal nerve (VN), the superior laryngeal nerve (SLN), and the recurrent laryngeal nerve (RLN). In the next step after the creation of the skin-platysma flap, the strap muscle’s lateral border was moved from the medial limb of the sternocleidomastoid without using any electrical device and without any manipulation of the thyroid gland. The VN was exposed in the carotid sheath and then stimulated using a monopolar probe at a precisely defined point above the clavicle, using anatomical landmarks. Results: In total, 136 women with a mean age of 40 years (range 18–74) and 36 men with a mean age of 42 (range 21–66), demonstrating 270 nerves at risk, were included in the analysis. Indications for surgery were malignancy in 70 cases, toxic goiter/Graves in 23 cases, retrosternal goiter in 21, and symptomatic multinodular goiter in 64 cases. Of these, 100 patients received a total thyroidectomy, 46 received a right lobectomy, and 24 received a left lobectomy only. For a total thyroidectomy, the median skin-to-skin surgery duration was 52 min (range 24–104 min) and the median hospital stay was 2 days (range 1–4 days). In 4 cases (4/146; 2.74%) the pre-dissection stimulation of the vagal nerve (VN1) at the ADNM’s precisely defined point did not create any signal or proper EMG-curve that indicated the existence of the non-RLN. Proximal dissection of the right VN at a precisely defined point by the ADNM’s level of incisura of the larynx created a positive signal. The separation point of the right non-RLN from the VN was discovered in all four patients. The postoperative video-laryngoscopy confirmed bilateral mobile vocal cords in all cases. Conclusions: Following the ADNM protocol during thyroid surgery minimizes the risk of a non-laryngeal nerve injury and prevents voice dysfunction.

Robotic bilateral axillo-breast versus endoscopic bilateral areola thyroidectomy outcomes of 757 patients

BACKGROUND

Remote endoscopic thyroidectomy (ET) and robotic thyroidectomy (RT) seem to be beneficial in selected situations to avoid anterior neck scars. There are limited data in the literature to determine whether RT via a bilateral axillo-breast approach (RT-BABA) is superior to ET via a bilateral areolar approach (ET-BAA). Therefore, the aim of this study was to evaluate the surgical outcomes of RT-BABA versus ET-BAA.

METHODS

Between May 2013 and May 2022, 757 patients who underwent RT-BABA or ET-BAA at a high-volume Chinese thyroid center were included. Intraoperative and postoperative outcome parameters were collected and retrospectively analyzed. The moving average method was used to evaluate the learning curve.

RESULTS

The proportion of patients older than 45 years was greater in the RT group than in the ET group (14.8% vs. 7.4%, p < 0.001). The percentage of overweight patients was greater in the RT group (28.8% vs. 9.5%, p < 0.001). The number of patients treated for malignant lesions was higher in the RT group (86.8% vs. 75%, p < 0.001). The rate of thyroiditis was higher in the RT group (10.9% vs. 6.6%, p < 0.001). Surgical time was significantly shorter in the RT group (140 vs. 165min, p < 0.001). Drainage volume was higher in the RT group (100 vs. 85ml, p < 0.001). Postoperative hospital stay was shorter in the RT group (3.04 ± 0.44 vs. 3.67 ± 0.89 days, p < 0.001). The cost in the RT group was higher (49627 ± 2795 vs. 25094 ± 3368 yuan, p < 0.001). Transient vocal cord dysfunction was lower in the RT group (2.9% vs. 8.0%, p = 0.003). There was no significant difference between the two groups in the number of central lymph nodes sampled, positive lymph nodes, neural monitoring (EMG) results, and rate of transient hypoparathyroidism. The learning curve for RT was 26 cases, and the operative time for ET was constant throughout the study.

CONCLUSIONS

RT-BABA is as safe and feasible as ET-BAA. RT-BABA performed better in some surgical outcomes. Further prospective studies are needed to confirm the safety of RT-BABA.