Lateral Mobilization of the Recurrent Laryngeal Nerve to Facilitate Tracheal Surgery in Patients with Thyroid Cancer Invading the Trachea Near Berry’s Ligament

Relationship of Recurrent Laryngeal Nerve with Inferior Horn of Thyroid Cartilage, Berry's Ligament and Zuckerkandl's Tubercle

During neck surgery; Zuckerkandl's tubercle, Berry's ligament, the inferior horn of thyroid cartilages have become crucial anatomical landmarks in order to protect the integrity of the recurrent laryngeal nerve. Forty-two male postmortem human cadavers were used. The proximal part of the recurrent laryngeal nerve, before the inferior thyroid artery arises from its source has been observed in 87% inside the tracheoesophageal groove and in 13% running laterally to the trachea. The recurrent laryngeal nerve was encountered passing behind and through the branches of the inferior thyroid artery in 92% and 8% respectively. At all sides; the nerve was piercing the larynx 0.6 ± 0.1 mm below the inferior horn of thyroid cartilage, passing next to the inner-lower side of Berry's ligament and running under the lower middle part of Zuckerkandl's tubercle. These landmarks and their upper mentioned distances to the laryngeal nerve can be taken into consideration as important surgical guides.

Novel surgical methods for reconstruction of the recurrent laryngeal nerve: Microscope-guided partial layer resection and intralaryngeal reconstruction of the recurrent laryngeal nerve

BACKGROUND

The optimal strategy for surgical management of papillary thyroid carcinoma invasion of the recurrent laryngeal nerve remains controversial. Our aim was to evaluate the efficacy of 2 surgical methods and provide detailed descriptions of microscope-guided partial layer resection and intralaryngeal reconstruction of the recurrent laryngeal nerve.

METHODS

This retrospective study enrolled 85 patients with papillary thyroid carcinoma who underwent initial surgical excision for invasion of the recurrent laryngeal nerve. Twenty-seven patients (28 recurrent laryngeal nerve sites) underwent partial layer resection, and 11 patients (11 recurrent laryngeal nerve sites) underwent intralaryngeal reconstruction of the recurrent laryngeal nerve. The remaining patients underwent either only resection or resection with immediate reconstruction of the recurrent laryngeal nerve. Pre and postoperative phonetic function and rates of locoregional recurrence were extracted from medical charts for analysis.

RESULTS

Isolated locoregional recurrence specific to the aerodigestive tract was identified in 1 patient (3.7%) in the partial layer resection group and 1 patient (9.1%) in the intralaryngeal reconstruction group. Seventy-five percent of patients in the partial layer resection group recovered or had preserved vocal cord function, and the mean maximum phonation time of the patients with postoperative complete vocal cord palsy was 15.3 seconds. The mean maximum phonation time of the patients, excluding 4 patients with permanent stoma in the intralaryngeal reconstruction group, was 22.3 seconds. The mean maximum phonation time of either group was longer than that of patients with recurrent laryngeal nerve resection only and comparable with that of patients with recurrent laryngeal nerve resection and immediate reconstruction.

CONCLUSION

Patients who underwent either partial layer resection or intralaryngeal reconstruction had low rates of locoregional recurrence specific to the aerodigestive tract and good postoperative functional outcomes.

Tracheal Resection in the Management of Thyroid Cancer: An Evidence-Based Approach

OBJECTIVE

Determine the effect of patient demographics and surgical approach on patient outcomes after tracheal resection in the management of thyroid cancer.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

Systematic review of literature was performed using PubMed, Embase, and Cochrane Library to identify patients with thyroid carcinoma who underwent tracheal resection. Pooled estimates for patient demographics, presenting findings, complications, and outcomes are determined using random-effects meta-analyses.

RESULTS

Ninety-six relevant studies encompassing 1,179 patients met inclusion criteria. Meta-analysis pooled rates of complications: 1.7% (confidence interval [CI] 0.8-2.5; P < .001; I² = 1.85%) airway complications, 2.8% (CI 1.6-3.9; P < .001; I² = 13.34%) bilateral recurrent laryngeal nerve paralysis, 2.2% (CI 1.2-3.1; P < .001; I² = 6.72%) anastomotic dehiscence. Circumferential resection pooled estimates major complications, locoregional recurrence, distal recurrence, overall survival: 14.1% (CI 8.3-19.9; P < .001; I² = 35.26%), 15% (CI 9.6-20.3; P < .001; I² = 38.2%), 19.7% (CI 13.7-25.8; P < .001; I² = 28.83%), 74.5% (CI 64.4-84.6; P < .001; I² = 85.07%). Window resection estimates: 19.8% (CI 6.9-32.8; P < .001; I² = 18.83%) major complications, 25.6% (CI 5.1-46.1; P < .014; I² = 84.68%) locoregional recurrence, 15.6% (CI 9.7-21.5; P < .001; I² = 0%) distal recurrence, 77.1% (CI 58-96.2; P < .001; I² = 78.77%) overall survival.

CONCLUSION

Management of invasive thyroid carcinoma may require tracheal resection to achieve locoregional control. Nevertheless, postoperative complications are not insignificant, and therefore this risk cannot be overlooked when counseling patients perioperatively. Laryngoscope, 131:932-946, 2021.

Staged Surgery for Advanced Thyroid Cancers: Safety and Oncologic Outcomes of Neural Monitored Surgery

Objective

Thyroidectomy with extensive multicompartment bilateral neck dissections for advanced-stage thyroid cancer may lead to increased risk of complications, including bilateral recurrent laryngeal nerve (RLN) paralysis and hypoparathyroidism. A planned staged approach derived from a detailed preoperative radiographic map is associated with a low complication profile. This study evaluates oncologic results and safety of neural monitored, staged thyroid cancer surgery for management of advanced thyroid cancer.

Study Design

Case series with chart review.

Setting

Tertiary care center.

Subjects and Methods

With institutional review board approval, 35 consecutive patients with advanced thyroid malignancy and extensive nodal disease managed with staged surgery between January 2004 and May 2013 by the senior author (G.W.R.) were identified, and the oncologic and surgical outcomes were reviewed.

Results

In total, 37.2% of patients had stage III or IV disease, with extrathyroidal extension in 71.4%, vascular invasion in 51.4%, and RLN invasion in 17% of patients. A total of 34% patients had positive lymph nodes in more than 5 nodal compartments; the average positive lymph node yield was 17, and extranodal extension was present in 51%. Three patients had RLN sacrifice, and there were no other cases of temporary or permanent RLN paralysis; permanent hypoparathyroidism and chyle leak occurred in one patient each. Locoregional recurrence occurred in 5.7% of patients after a 147-week mean follow-up. In patients with papillary thyroid carcinoma, median postoperative nonstimulated and stimulated thyroglobulin levels were 0.2 and 0.75 ng/mL, respectively.

Conclusion

A neural monitored, staged surgical approach was conducted without significant adverse events in this small sample and represents and effective alternative strategy option to simultaneous bilateral surgery in the management of thyroid cancer with extensive neck metastases.

Salient anatomical landmarks of thyroid and their practical significance in thyroid surgery: a pictorial review of thyroid surgical anatomy (revisited)

Thyroid surgery is a prototype of operations requiring thorough knowledge of surgical anatomy. There are many vital and delicate anatomical structures such as recurrent laryngeal nerve, superior laryngeal nerve, parathyroid glands, and distinct fascial planes surrounding the thyroid gland. A protean range of pathologies such as goiter, nodules, thyroiditis, and malignancy distort or alter the location and course of these structures and planes. The distinct vascular supply and high vascularity of thyroid region challenges the surgeon's expertise. Several pathologies like malignancy, multinodularity, toxicity, and retrosternal extension further compounds this vascular aspect of surgery. Several structures of embryological importance such as pyramidal lobe, tubercle of Zuckerkandl, and ligament of Berry have decisive clinical implications in the surgical management of thyroid disorders. Surgeons attempting thyroidectomy need to have thorough knowledge of embryology and surgical anatomy of the thyroid gland. In this context, we highlight through a pictorial assay the embryological and anatomical aspects of the thyroid gland emphasizing on their clinical and surgical importance.

The role of immediate recurrent laryngeal nerve reconstruction for thyroid cancer surgery

Unilateral vocal fold paralysis (UVFP) is one of the most serious problems in conducting surgery for thyroid cancer. Different treatments are available for the management of UVFP including intracordal injection, type I thyroplasty, arytenoid adduction, and laryngeal reinnervations. The effects of immediate recurrent laryngeal nerve (RLN) reconstruction during thyroid cancer surgery with or without UVFP before the surgery were evaluated with videostroboscopic, aerodynamic, and perceptual analyses. All subjects experienced postoperative improvements in voice quality. Particularly, aerodynamic analysis showed that the values for all patients entered normal ranges in both patients with and without UVFP before surgery. Immediate RLN reconstruction has the potential to restore a normal or near-normal voice by returning thyroarytenoid muscle tone and bulk seen with vocal fold denervation. Immediate RLN reconstruction is an efficient and effective approach to the management of RLN resection during surgery for thyroid cancer.

Improvement in phonation after reconstruction of the recurrent laryngeal nerve in patients with thyroid cancer invading the nerve

BACKGROUND

We report vocal improvement after reconstruction of the recurrent laryngeal nerve (RLN) in patients with nerve resection, although vocal cord movement was not restored. These methods are not widely recognized.

METHODS

Direct anastomosis, free nerve grafting, or anastomosis to the ansa cervicalis or the vagus nerves with the RLN were performed in 7, 14, 65, and 2 patients with thyroid cancer invading the RLN, respectively. A total of 51 patients had vocal cord paralysis (VCP) pre-operatively. Maximum phonation time (MPT) and vital capacity (VC) were measured before and 1 year after reconstruction. A total of 34 normal subjects and 27 patients with VCP served as controls.

RESULTS

Patients with VCP had significantly shorter MPT values than normal subjects. At 1 year after operation, patients with reconstruction had values of MPT similar to those of normal subjects. Men had significantly longer MPT values than women, but the phonation efficiency index (PEI), defined as the MPT/VC ratio, did not differ by sex. The PEI was significantly less in VCP patients than in normal subjects. Patients with reconstruction achieved PEI values similar to those in normal subjects. Phonation efficiency index values at 1 year after operation was significantly greater than pre-operative PEI and was not affected by the presence or absence of VCP pre-operatively, age, reconstruction method, thickness of suture thread, or use of magnification during the operation.

CONCLUSION

In patients with thyroid cancer requiring RLN resection, RLN reconstruction achieved recovery in phonatory function.