Recurrent laryngeal nerve monitoring during totally robot-assisted Ivor Lewis esophagectomy

Recurrent Laryngeal Nerve Intraoperative Neuromonitoring Indications in Non-Thyroid and Non-Parathyroid Surgery

Introperative nerve monitoring (IONM) of the recurrent laryngeal nerve (RLN) is a well-established technique to aid in thyroid/parathyroid surgery. However, there is little evidence to support its use in non-thyroid or non-parathyroid surgery. The aim of this paper was to review the current evidence regarding the use of IONM in non-thyroid/non-parathyroid surgery in the head and neck and thorax. A literature search was performed from their inception up to January 2024, including the term "recurrent laryngeal nerve monitoring". IONM in non-thyroid/non-parathyroid surgery has mainly been previously described in oesophageal surgery and in tracheal resections. However, there is little published evidence on the role of IONM with other resections in the vicinity of the RLN. Current evidence is low-level for the use of RLN IONM in non-thyroid/non-parathyroid surgery. However, clinicians should consider its use in surgery for pathologies where the RLN is exposed and could be injured.

Precise pattern of lymphatic spread of esophageal squamous cell carcinoma: results of 1074 patients with N1 disease

PURPOSE

The route of lymphatic spread in esophageal cancer remains unclear. The present study aimed to determine the pattern of lymphatic metastasis in its early stages.

METHODS

The data were reviewed of 1074 patients who underwent curative esophagectomy for thoracic esophageal squamous cell carcinoma and metastasis in 1-2 lymph nodes between January 2015 and December 2021. The frequencies of lymph node metastasis were analyzed by the anatomic sites and regions involved.

RESULTS

Of the 1074 patients, 668 patients (62.2%) with one positive lymph node and 406 (37.8%) with two positive lymph nodes. Paracardial lymph nodes were the most frequently involved nodes (35.1%), followed by right thoracic recurrent nerve nodes (24.0%), middle thoracic paraesophageal nodes (14.7%), left thoracic recurrent nerve nodes (10.4%), subcarinal nodes (8.0%), lower thoracic paraesophageal nodes (7.8%), and upper thoracic paraesophageal nodes (5.7%). The frequency of lymph node metastasis in other sites was less than 3%. The majority of lymph node metastases occurred in the longitudinal direction to the perigastric (36.5%) and bilateral recurrent nerve regions (33.4%) and in the transverse direction to the paraesophageal region (27.7%). As the tumor location changed from the upper to the lower thoracic esophagus, the frequencies of lymph node metastasis decreased in the bilateral recurrent nerve region but increased in the perigastric region.

CONCLUSION

Bilateral recurrent nerve nodes, paraesophageal lymph nodes, and perigastric nodes were the most common sites of early lymph node metastasis. Esophageal squamous cell carcinoma involves more longitudinal than transverse lymph node metastases.

Application of intraoperative nerve monitoring for recurrent laryngeal nerves in minimally invasive McKeown esophagectomy

BACKGROUND

Mediastinal lymphadenectomy is of great importance during esophagectomy for esophageal squamous cell carcinoma. However, recurrent laryngeal nerve (RLN) injury is a severe complication caused by lymphadenectomy along the RLN. Intraoperative nerve monitoring (IONM) can effectively identify the RLN and reduce the incidence of postoperative vocal cord paralysis (VCP). Here, we describe the feasibility and effectiveness of IONM in minimally invasive McKeown esophagectomy.

METHODS

A total of 150 patients who underwent minimally invasive McKeown esophagectomy from 2016 to 2020 were enrolled in this study. We divided the patients into two groups: a neuromonitoring group (IONM, n = 70) and a control group (control, n = 80). Clinical data, surgical variables, and postoperative complications were retrospectively analyzed and compared.

RESULTS

There was no significant difference in baseline data between the two groups. Postoperative VCP occurred in six cases (8.6%) in the IONM group, which was lower than that in the control group (21.3%, P = 0.032). Postoperative pulmonary complications were found in five cases (7.1%) and 14 in the control group (18.8%, P = 0.037). The postoperative hospital stay in the IONM group was significantly shorter than that in the control group (8 vs. 12, median, P < 0.001). The number of RLN lymph nodes harvested in the IONM group was higher than that in the control group (13.74 ± 5.77 vs. 11.03 ± 5.78, P = 0.005). The sensitivity and specificity of IONM monitoring VCP were 83.8% and 100%, respectively. A total of 66.7% of patients with a reduction in signal showed transient VCP, whereas 100% with a loss of signal showed permanent VCP.

CONCLUSION

IONM is feasible in minimally invasive McKeown esophagectomy. It showed advantages for distinguishing RLN and achieving thorough mediastinal lymphadenectomy with less RLN injury. Abnormal IONM signals can provide an accurate prediction of postoperative VCP incidence.

Efficacy of Intraoperative Recurrent Laryngeal Nerve Monitoring During Thoracoscopic Esophagectomy for Esophageal Cancer: A Systematic Review and Meta-Analysis

Background: Recurrent laryngeal nerve paralysis (RLNP), a severe complication of mini-invasive esophagectomy, usually occurs during lymphadenectomy adjacent to recurrent laryngeal nerve. This systematic review and meta-analysis aimed to evaluate the efficacy of intraoperative nerve monitoring (IONM) in reducing RLNP incidence during mini-invasive esophagectomy. Methods: Systematic literature search of PubMed, EMBASE, EBSCO, Web of Knowledge, and Cochrane Library until June 4, 2021 was performed using the terms "(nerve monitoring) OR neuromonitoring OR neural monitoring OR recurrent laryngeal nerve AND (esophagectomy OR esophageal)." Primary outcome was postoperative RLNP incidence. Secondary outcomes were sensitivity, specificity, and positive and negative predictive values for IONM; complications after esophagectomy; number of dissected lymph nodes; operation time; and length of hospital stay. Results: Among 2,330 studies, five studies comprising 509 patients were eligible for final analysis. The RLNP incidence was significantly lower (odds ratio [OR] 0.33, 95% confidence interval [CI] 0.12-0.88, p < 0.05), the number of dissected mediastinal lymph nodes was significantly higher (mean difference 4.30, 95%CI 2.75-5.85, p < 0.001), and the rate of hoarseness was significantly lower (OR 0.14, 95%CI 0.03-0.63, p = 0.01) in the IONM group than in the non-IONM group. The rates of aspiration (OR 0.31, 95%CI 0.06-1.64, p = 0.17), pneumonia (OR 1.08, 95%CI 0.70-1.67, p = 0.71), and operation time (mean difference 7.68, 95%CI -23.60-38.95, p = 0.63) were not significantly different between the two groups. The mean sensitivity, specificity, and positive and negative predictive values for IONM were 53.2% (0-66.7%), 93.7% (54.8-100%), 71.4% (0-100%), and 87.1% (68.0-96.6%), respectively. Conclusion: IONM was a feasible and effective approach to minimize RLNP, improve lymphadenectomy, and reduce hoarseness after thoracoscopic esophagectomy for esophageal cancer, although IONM did not provide significant benefit in reducing aspiration, pneumonia, operation time, and length of hospital stay.