A case report of ansa cervicalis to spinal accessory transposition graft: a new surgical technique to prevent shoulder dysfunction.

Introduction and importance: The spinal accessory nerve is at risk when performing neck dissections for head and neck cancers. Injury to this nerve can result in shoulder syndrome, which can be challenging to manage. Various nerve repair or grafting methods are available to prevent this condition. A safe, simple, and cost-effective option is the ansa cervicalis to spinal accessory transposition graft. Case presentation: A 60-year-old Afro-Trinidadian female presented to the Outpatient clinic for evaluation of a scalp lesion and a large neck mass for a duration of one year. Preoperative tissue biopsies confirmed she had squamous cell cancer with metastatic spread to the cervical nodes. The patient underwent surgical excision of the scalp lesion and left neck dissection with the sacrifice of the sternocleidomastoid and the left spinal accessory nerve due to tumour involvement. During the procedure, the ansa cervicalis was successfully joined to the distal remainder of the spinal accessory nerve. After the surgery, the patient fully recovered and achieved a good quality of life during the 24-month follow-up. Clinical discussion: This is the first reported case of using the ansa cervicalis to reinnervate the trapezius muscle through the spinal accessory nerve. This procedure aims to prevent pain, muscle wasting, and adhesive capsulitis. A quality-of-life questionnaire and adequate range of motion proved the success of this procedure, demonstrating that this option provides practical, functional, and aesthetic benefits for patients. Conclusion: The ansa cervicalis to spinal accessory transposition nerve graft is a valuable option for reinnervation. This case report highlights the effectiveness of this single-stage procedure in preventing shoulder syndrome.

Immediate Ansa cervicalis-to-recurrent laryngeal nerve low-tension anastomosis: A new technique for phonation recovery and bilateral anastomoses to avoid tracheotomy.

OBJECTIVE: This case series study investigated the outcomes of an innovative approach, ansa cervicalis nerve (ACN)-to-recurrent laryngeal nerve (RLN) low-tension anastomosis. METHODS: Patients who received laryngeal nerve anastomosis between May 2015 and September 2021 at the facility were enrolled. The inclusion criteria were patients with RLN dissection and anastomosis immediately during thyroid surgery. Exclusion criteria were cases with anastomosis other than cervical loop-RLN anastomosis or pronunciation recovery time > 6 months. Patients admitted before January 2020 were assigned to group A which underwent the conventional tension-free anastomosis, and patients admitted after January 2020 were group B and underwent the innovative low-tension anastomosis (Dong's method). RESULTS: A total of 13 patients were included, 11 patients received unilateral surgery, and 2 underwent bilateral surgery. For patients who underwent unilateral anastomosis, group B had a significantly higher percentage of normal pronunciation via GRBAS scale (83.3 % vs. 0 %, p = 0.015) and voice handicap index (66.7 % vs. 0 %, p = 0.002), and shorter recovery time in pronunciation (median: 1-day vs. 4 months, p = 0.001) than those in group A after surgery. CONCLUSIONS: ACNs-to-RLN low-tension anastomosis with a laryngeal segment ≤1 cm (Dong's method) significantly improves postoperative pronunciation and recovery time. The results provide clinicians with a new strategy for ACN -to-RLN anastomosis during thyroid surgery.

New strategy for intraoperative phonosurgical management of recurrent laryngeal nerve infiltrated by thyroid carcinoma.

PURPOSE: Treating an infiltration of the recurrent laryngeal nerve (RLN) by thyroid carcinoma remains a subject of ongoing debate. Therefore, this study aims to provide a novel strategy for intraoperative phenosurgical management of RLN infiltrated by thyroid carcinoma. METHODS: Forty-two patients with thyroid carcinoma infiltrating the RLN were recruited for this study and divided into three groups. Group A comprised six individuals with medullary thyroid cancer who underwent RLN resection and arytenoid adduction. Group B consisted of 29 differentiated thyroid cancer (DTC)patients who underwent RLN resection and ansa cervicalis (ACN)-to-RLN anastomosis. Group C included seven patients whose RLN was preserved. RESULTS: The videostroboscopic analysis and voice assessment collectively indicated substantial improvements in voice quality for patients in Groups A and B one year post-surgery. Additionally, the shaving technique maintained a normal or near-normal voice in Group C one year post-surgery. CONCLUSION: The new intraoperative phonosurgical strategy is as follows: Resection of the affected RLN and arytenoid adduction is required in cases of medullary or anaplastic carcinoma, regardless of preoperative RLN function. Suppose RLN is found infiltrated by well-differentiated thyroid cancer (WDTC) during surgery, and the RLN is preoperatively paralyzed, we recommend performing resection the involved RLN and ACN-to-RLN anastomosis immediately during surgery. If vocal folds exhibit normal mobility preoperatively, the MACIS scoring system is used to assess patient risk stratification. When the MACIS score > 6.99, resection of the involved RLN and immediate ACN-to-RLN anastomosis were performed. RLN preservation was limited to patients with MACIS scores ≤ 6.99.

Ansa Cervicalis External Branch Anastomosis to Restore High Tone Voice in Thyroid Surgery.

OBJECTIVES: Injury to the external branch of the superior laryngeal nerve (EBSLN) causes low-pitch voice and voice fatigue, particularly in female subjects, and available treatments are limited. Here, we assess a novel surgical procedure to restore a high-tone voice: ansa cervicalis to EBSLN anastomosis (A-E anastomosis). METHODS: Between November 2012 and April 2022, 13 patients (12 female) underwent unilateral EBSLN resection and A-E anastomosis, while 20 (16 female) underwent EBSLN resection during thyroid surgery. Patients (4494 women and 1025 men) with normal laryngoscopy scheduled for thyroid surgery served as normal controls. Phonatory function was examined using a Phonation Analyzer PA-1000 preoperatively and intermittently postoperatively. RESULTS: In patients who underwent A-E anastomosis, high-tone voice pitch decreased significantly postoperatively (673.9-471.5 Hz, p = 0.047), with restoration achieved within 5 months. The mean voice pitch in female patients who underwent A-E anastomosis, EBSLN resection, and controls were 580.4, 522.8, and 682.0 Hz, respectively, indicating a significant decrease in EBSLN resection patients than controls (p = 0.002). The (mean - 1SD) of high-tone voice pitch in female controls was 497 Hz; exceeding this may indicate recovery to a high-tone voice. Overall, 73% (8/11) of A-E anastomosis patients exceeded this value, which was marginally larger than the 43% (6/14) who underwent EBSLN resection. Data on male subjects are limited. There were no cases of adverse functional or cosmetic events. CONCLUSIONS: A-E anastomosis, a novel simple procedure, restored high-tone voice to some extent without any adverse events and thus warrants further investigation. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:3868-3873, 2024.

Anastomosis between the facial nerve - ansa cervicalis and the facial nerve - hypoglossal nerve in rabbits: technical note for a practical use in peripheral facial palsy.

Background and aims: To emphasize the importance of laboratory dissections in perfecting surgical techniques. In this paper, we describe the technical details on rabbit dissection for practical applications. Methods: Four New Zealand rabbits were distributed into two groups and underwent anastomosis between the Facial Nerve and Ansa Cervicalis (group 1) and between the Facial Nerve and Hypoglossal Nerve (group 2). They were clinically and neurophysiologically evaluated after ten weeks. Electroneurography with skin electrodes were used to identify the motor activity of the involved muscles and nerves. Facial and ipsilateral tongue reinnervation was analyzed 40 weeks after anastomosis. Evoked electromyographic muscle tension was used to evaluate facial and tongue reinnervation. Results: Facial and ipsilateral tongue reinnervation was analyzed 40 weeks after anastomosis. Recorded evoked potentials showed improvement in facial reinnervation in all four rabbits. Rabbits undergoing FN-HN anastomosis still showed ipsilateral lingual paresis, based on EMG tests. The survival rate was 100%. Conclusions: The laboratory dissection plays a crucial role in training surgical specialists to achieve favorable patient outcomes. Both types of anastomosis can be used to achieve facial reinnervation; however, it is imperative to prevent ipsilateral lingual paralysis that may arise from using the hypoglossal nerve.

Duplication of the Hypoglossal Nerve Branch to the Thyrohyoid Muscle: A Case Report.

The motor fibers to the thyrohyoid muscle are provided by the anterior ramus of C1 via the hypoglossal nerve rather than via the ansa cervicalis. Knowledge of possible variations in the branching patterns of the nerves attached to the hypoglossal nerve is necessary to minimize iatrogenic injury to these structures during surgical procedures. We describe a rare anatomical variant of the nerve branch to the thyrohyoid muscle. To our knowledge, this particular variant has not been previously reported.

Extracranial hypoglossal neurofibroma with a variant ansa cervicalis: a case report.

PURPOSE: This case report aims to explore a rare combination of findings in a cadaver donor: variant ansa cervicalis, vagus (CN X) and hypoglossal (CN XII) nerve fusion, and extracranial hypoglossal neurofibroma. BACKGROUND: The type of ansa cervicalis variation presented in this report has been documented in less than 1% of described cases. The CN X-CN XII fusion has been reported in one prior study. Additionally, hypoglossal neurofibromas are benign neoplasms of the peripheral nerve sheath. There are only two known cases of extracranial hypoglossal neurofibroma described in the literature. CASE REPORT: The study investigated a swelling of the right CN XII in a 90-year-old female cadaver donor. Detailed dissection, examination of the region, and histopathological analysis of the mass followed. The entire course of CN XII and other cranial nerves were examined to exclude concurrent pathology. A fusiform enlargement of the right CN XII was observed in the submandibular region, measuring ~ 1.27 × 1.27 cm. The superior portion of the right CN XII was fused to the right CN X, exiting the jugular foramen. The superior root of ansa cervicalis, normally a branch of CN XII, was found to arise from CN X on the right side. The left CN XII and CN X were unremarkable. Histopathological examination revealed benign neurofibroma. CONCLUSION: The anatomical variation and rare location of the tumor necessitate further investigation to better understand pathogenesis, clinical correlation, and surgical implications. This study furthers knowledge of this condition and contributes to the currently limited body of research.

Timing of Ansa Cervicalis-to-recurrent Laryngeal Nerve Reinnervation: A Systematic Review.

BACKGROUND: Ansa cervicalis-to-recurrent laryngeal nerve anastomosis (ARA) is an established technique for the treatment of recurrent laryngeal nerve (RLN) injury after head and neck surgery. However, the optimal timing of ARA remains unclear, and the evidence bases for ARA performed at each timepoint after RLN injury have not previously been clearly distinguished. We conducted a systematic review of the literature to evaluate the efficacy of ARA performed at different timepoints on postoperative voice outcomes. METHODS: A review of English-language journal articles published in the last 20 years was undertaken on three electronic databases: Ovid MEDLINE, PubMed and Embase. Studies with a focus on paediatric RLN injury, bilateral RLN injury, ansa cervicalis anatomy and non-ARA techniques alone were excluded. RESULTS: Twenty eight articles were included in the review. ARA was performed as a delayed surgery in 16/28 studies (57%), while immediate ARA was utilized in 14/28 studies (50%). On qualitative synthesis, delayed ARA was shown to be effective in improving patient-reported, subjective observer-reported and objective observer-reported voice outcomes. Likewise, a substantial body of evidence was identified demonstrating postoperative voice improvement with immediate ARA. On direct comparison of timepoints, some benefit was shown for early delayed ARA relative to late delayed operations, while no comparative data for immediate versus delayed repair were available in the literature. CONCLUSIONS: ARA at both delayed and immediate timepoints is effective in the treatment of patients with RLN injury after head and neck surgery. The timing of ARA may have some influence on its efficacy, with early delayed repair potentially associated with superior outcomes to late delayed operations, and immediate ARA offering several practical advantages relative to delayed repair. Further comparative studies are required to better characterize the optimal timing of ARA after RLN injury.

Endotracheal Tube Electrode Neuromonitoring for Placement of Vagal Nerve Stimulation for Epilepsy: Intraoperative Stimulation Thresholds.

Vagal nerve stimulators (VNS) are indicated as a palliative treatment for medically refractory epilepsy. The vagus nerve may have a variable position within the carotid sheath and may be confused with a prominent ansa cervicalis. The objective of this study was to describe an intraoperative neuromonitoring technique for VNS placement and provide stimulation thresholds that may aid in the creation of stimulation protocols. A retrospective study was performed assessing 40 patients undergoing intraoperative vocal cord monitoring during vagal nerve stimulator placement surgery. Endotracheal electrodes were utilized to record vocal cord activity at various surgical time points. The stimulation thresholds were tested at the time of opening of the carotid sheath (mean 0.35 mA [range 0.08-1.00]), after full and circumferential dissection of the vagus nerve (0.34 mA [0.10-0.90]), after tenting of the vagus nerve in preparation for placement of the electrode (0.22 mA [0.06-1.20]), and after electrode placement (0.26 mA [0.05-1.20]). The vagus nerve was identified in all patients; it was located behind the common carotid artery (CCA) in two patients, on top of the internal jugular vein (IJV) in one patient, and in the typical location between the CCA and IJV in the remainder of patients. The average size of the vagus nerve was 2.9 mm [1.5-5.0]. Intraoperative vagus nerve stimulation represents a safe adjunctive tool that can help localize the nerve, particularly in the setting of varying anatomy or hazardous dissections. It may help reduce the potential for vagal trunk damage or electrode misplacement and potentially improve clinical outcomes.

Assessing the Efficacy of Anastomosis between Ansa Cervicalis and Facial Nerve for Patients with Concomitant Facial Palsy and Peripheral Neuropathy.

Background: For decades, patients with facial asymmetry have experienced social interaction difficulties, leading them to seek treatment in the hope of restoring facial symmetry and quality of life. Researchers evaluated numerous surgical techniques, but achieving results remains a significant hurdle. Specifically, anastomosis between the ansa cervicalis (AC) and facial nerve (FN) can hinder the patient's physical appearance. Objective: Our study goal was to examine the efficiency of anastomosis between AC and FN for facial motor function recovery even in the presence of peripheral neuropathy. Materials and Methods: Four patients diagnosed with facial palsy grade VI on the House & Brackmann Scale (HB) after vestibular schwannoma (VS) resection (Koos grade IV) via the retrosigmoid approach underwent AC and FN anastomosis. Outcomes were related to tumor grade, previous therapy, and the time between postoperative facial palsy and anastomosis. Images and neurophysiological data were evaluated. Results: After vs. resection, all four patients demonstrated HB grade VI facial palsy for an average of 17 months. During the follow-up program, lasting between 6 and 36 months, two patients were evaluated as having HB grade III facial palsy; the other two patients were diagnosed with grade IV HB facial palsy. None of the patients developed tongue atrophy, speech disorder, or masticatordys function. Conclusions: Anastomosis between the AC and FN is a safe and effective treatment for facial paralysis after cerebellopontine tumor resection. Nerve reanimation may be feasible even for patients with peripheral polyneuropathy. This study also offers a new option for patients with a progression-free status.

An unusual location of the ansa cervicalis.

The ansa cervicalis (AC) is part of the cervical plexus and is formed by the ventral rami of spinal nerves C1-C3. It is usually formed by two roots that run parallel to each other and then form a loop anterior to the internal jugular vein. Herein, we report a rare case where the AC was found deep to the internal carotid artery and common carotid artery and had sympathetic contributions.

Dual laryngeal reinnervation in bilateral vocal fold paralysis: anatomical pitfalls.

BACKGROUND: Bilateral laryngeal reinnervation can be a promising procedure for reanimation of laryngeal muscles, but currently not yet standardized. Besides patient conditions some intraoperative anatomical pitfalls need to be solved. METHODS: Twelve human head and neck specimens (24 sides) have been studied using microdissection and histological serial sections of the nerves. The surgical anatomy of the dual reinnervation procedure according to JP Marie was investigated notably the branching pattern of the phrenic nerve (PN), the Ansa cervicalis (AC) and the recurrent laryngeal nerve (RLN). RESULTS: Despite variations of the AC, a prominent inferior common trunk for sterno-hyoid and sterno-thyroid muscles can be used in more than 90% of the specimens. If the AC is missing because of previous surgery, the tiny nerve of the thyro-hyoid muscle can be used preferred. The PN display a double roots pattern from C3 to C4 cervical plexus in 50% of the specimens. A single root pattern can be found and an end-to-lateral neurorraphy can be used. Intra-laryngeal nerves pattern of the RLN display tiny collaterals which cannot be selected for abduction-adduction activity. Direct implantation of the Y-shape great auricular nerve within the posterior crico-arytenoid muscles can be a reliable method leading to challenging mechanical and functional conditions. CONCLUSION: Several anatomical pitfalls, including intra-operative choices and variants of the donor nerves, but also the challenging intra-laryngeal dissection of the inferior laryngeal nerve need to be solved. A successful laryngeal reinnervation still needs further studies for a simplified procedure.

Ansa cervicalis stimulation increases pharyngeal patency in patients with obstructive sleep apnea.

Hypoglossal nerve stimulation (HNS) is an alternative treatment option for obstructive sleep apnea (OSA) that reduces pharyngeal collapsibility, but HNS nonresponders often demonstrate continued retropalatal and lateral pharyngeal wall collapse. Recent evidence suggests that caudal pharyngeal traction with sternothyroid muscle contraction via ansa cervicalis stimulation (ACS) can also stabilize the pharynx, but the underlying mechanisms have not been elucidated. Our objective was to evaluate the effect of ACS on pharyngeal patency during expiration when the airway is most hypotonic. Eight participants with OSA underwent sustained ultrasound-guided fine-wire stimulation of the medial branch of the right hypoglossal nerve with and without transient stimulation of the branch of the ansa cervicalis nerve plexus innervating the right sternothyroid muscle during drug-induced sleep endoscopy. Airway cross-sectional area and expiratory airflow (V̇e) were measured from endoscopy video with ImageJ and pneumotachometry, respectively. ACS significantly increased retropalatal cross-sectional area (CSARP) to 211% [159-263] of unstimulated CSARP (P < 0.05). Adding ACS to HNS increased CSARP from baseline by 341% [244-439] (P < 0.05), a 180% [133-227] increase over isolated HNS (P < 0.05). ACS increased V̇e from baseline by 177% [138-217] P < 0.05). Adding ACS to HNS increased V̇e by 254% [207-301], reflecting decreases in pharyngeal collapsibility. Combining ACS with HNS increased retropalatal cross-sectional area and increased expiratory airflow, suggesting decreases in pharyngeal collapsibility. Our findings suggest that ACS exerts caudal traction on the upper airway through sternothyroid muscle contraction and that it may augment HNS efficacy in patients with OSA.NEW & NOTEWORTHY Ansa cervicalis stimulation (ACS) is a recently proposed neurostimulation mechanism for generating caudal pharyngeal traction that may benefit patients with obstructive sleep apnea. Here, we document endoscopic findings with ACS during drug-induced sleep endoscopy and additionally detail the effects of ACS on expiratory airflow, when the pharynx is known to be most hypotonic.

Association of Tortuous Common Carotid Artery with Abnormal Distribution of the Ansa Cervicalis: A Case Report.

In the current study, we display a rare association of an aberrant innervation of the sternocleidomastoid muscle by the ansa cervicalis (AC) with a tortuous common carotid artery (TCCA). In specific, in a male cadaver we observed on the right side of the cervical region, a nerval branch of remarkable size originating from the most distal part of the AC's superior root and after piercing the superior belly of the omohyoid muscle innervated the distal portion of the sternocleidomastoid muscle. Furthermore, we noticed a tortuous course of the initial part of the right common carotid artery. We discuss the surgical significance of the awareness of AC's variations during neurotisation of the recurrent laryngeal nerve in cases of its damage, as well as the importance of aberrant innervation of the sternocleidomastoid muscle by AC for the preservation of muscle's functionality after accessory nerve's damage. Furthermore, we highlight the fact, that the knowledge of the relatively uncommon variant, such as TCCA is crucial for the physician in order to proceed more effectively in differential diagnosis of a palpable mass of the anterior cervical region or deal with symptoms such as dyspnea, dysphagia or symptoms of cerebrovascular insufficiency.

Ansa Cervicalis Stimulation: A New Direction in Neurostimulation for OSA.

BACKGROUND: Hypoglossal nerve stimulation (HNS) is an alternative treatment option for patients with OSA unable to tolerate positive airway pressure but implant criteria limit treatment candidacy. Previous research indicates that caudal tracheal traction plays an important role in stabilizing upper airway patency. RESEARCH QUESTION: Does contraction of the sternothyroid muscle with ansa cervicalis stimulation (ACS), which pulls the pharynx caudally via thyroid cartilage insertions, increase maximum inspiratory airflow (VImax)? STUDY DESIGN AND METHODS: Hook-wire percutaneous electrodes were used to stimulate the medial branch of the right hypoglossal nerve and right branch of the ansa cervicalis innervating the sternothyroid muscle during propofol sedation. VImax was assessed during flow-limited inspiration with a pneumotachometer. RESULTS: Eight participants with OSA were studied using ACS with and without HNS. Compared with baseline, the mean VImax increase with isolated ACS was 298%, or 473 mL/s (95% CI, 407-539). Isolated HNS increased mean VImax from baseline by 285%, or 260 mL/s (95% CI, 216-303). Adding ACS to HNS during flow-limited inspiration increased mean VImax by 151%, or 205 mL/s (95% CI, 174-236) over isolated HNS. Stimulation was significantly associated with increase in VImax in both experiments (P < .001). INTERPRETATION: ACS independently increased VImax during propofol sedation and drove further increases in VImax when combined with HNS. The branch of the ansa cervicalis innervating the sternothyroid muscle is easily accessed. Confirmation of the ansa cervicalis as a viable neurostimulation target may enable caudal pharyngeal traction as a novel respiratory neurostimulation strategy for treating OSA.

Ultrasound Localization and Percutaneous Electrical Stimulation of the Hypoglossal Nerve and Ansa Cervicalis.

OBJECTIVE: Hypoglossal nerve stimulation for obstructive sleep apnea (OSA) can be effective for appropriately selected patients, but current patient selection criteria are complex and still result in a proportion of nonresponders. Ansa cervicalis stimulation of the infrahyoid cervical strap muscles has recently been proposed as a new form of respiratory neurostimulation (RNS) therapy for OSA treatment. We hypothesized that percutaneous stimulation of both nerves in humans with temporary electrodes would make testing of the physiologic response to different RNS strategies possible. STUDY DESIGN: Nonrandomized acute physiology study. SETTING: Tertiary care hospital. METHODS: Fifteen participants with OSA underwent ultrasonography and placement of percutaneous electrodes proximal to the medial division of the hypoglossal nerve and the branch of the ansa cervicalis innervating the sternothyroid muscle (ACST). Procedural success was documented in each participant, as were any failures or procedural complication. RESULTS: The hypoglossal nerve was successfully localized in 15 of 15 (100%) participants and successfully stimulated in 13 of 15 (86.7%). The ACST was successfully localized in 15 of 15 (100%) participants and successfully stimulated in 14 of 15 (93.3%). Stimulation failure of the hypoglossal nerve was due to suboptimal electrode placement in 1 participant and electrode displacement in the other 2 cases. No complications occurred. CONCLUSIONS: The hypoglossal nerve and ACST can be safely stimulated via percutaneous electrode placement. Larger trials of percutaneous stimulation may help to identify responders to different RNS therapies for OSA with temporary or permanent percutaneous electrodes. Techniques for electrode design, nerve localization, and electrode placement are described.

Immediate Intraoperative Repair of the Recurrent Laryngeal Nerve in Thyroid Surgery.

OBJECTIVES: Recurrent laryngeal nerve (RLN) injury is a recognized risk during thyroid and parathyroid surgery and can result in significant morbidity. The aim of this review paper is to consider the optimal approach to the immediate intraoperative repair of the RLN during thyroid surgery. METHODS: A PubMed literature search was performed from inception to June 2020 using the following search strategy: immediate repair or repair recurrent laryngeal nerve, repair or reinnervation recurrent laryngeal nerve and immediate neurorraphy or neurorraphy recurrent laryngeal nerve. RESULTS: Methods of immediate intraoperative repair of the RLN include direct end-to-end anastomosis, free nerve graft anastomosis, ansa cervicalis to RLN anastomosis, vagus to RLN anastomosis, and primary interposition graft. Techniques of nerve repair include micro-suturing, use of fibrin glue, and nerve grafting. Direct micro-suture is preferable when the defect can be repaired without tension. Fibrin glue has also been proposed for nerve repair but has been criticized for its toxicity, excessive slow reabsorption, and the risk of inflammatory reaction in the peripheral tissues. When the proximal stump of the RLN cannot be used, grafting could be done using transverse cervical nerve, supraclavicular nerve, vagus nerve, or ansa cervicalis. CONCLUSIONS: Current evidence is low-level; however, it suggests that when the RLN has been severed, avulsed, or sacrificed during thyroid surgery it should be repaired intraoperatively. The immediate repair has on balance more advantages than disadvantages and should be considered whenever possible. This should enable the maintenance of vocal cord tone, better and prompter voice recovery and avoidance of aspiration. Laryngoscope, 131:1429-1435, 2021.

Immediate Ansa Cervicalis-to-Recurrent Laryngeal Nerve Anastomosis for the Management of Recurrent Laryngeal Nerve Infiltration by a Differentiated Thyroid Carcinoma.

OBJECTIVES: The optimal surgical approach to treat recurrent laryngeal nerve (RLN) infiltration by differentiated thyroid cancer (DTC) remains a subject of debate. This study explored the feasibility and efficiency of immediate ansa cervicalis nerve (ACN)-to-RLN anastomosis for the management of RLN infiltration by DTC. MATERIAL AND METHODS: Fifty-three patients who underwent immediate ACN-to-RLN anastomosis during DTC extirpation were enrolled in the present study. Thirty-seven cases presented with unilateral vocal cord paralysis before the operation (Group A), and another 16 patients presented with normal vocal cord mobility preoperatively (Group B). Multidimensional assessments, videostroboscopy, voice assessment, and laryngeal electromyography (LEMG) were performed preoperatively and postoperatively. RESULTS: All videostroboscopy, voice assessment and LEMG parameters in Group A deteriorated 1 month after the operation and improved 1 year after the operation compared with preoperative data. In Group B, all parameters 1 year after the operation improved significantly compared with the corresponding parameters 1 month after the operation. LEMG in Group A and B provided substantial evidence for the maturation of neural regeneration from ACN and demonstrated that the laryngeal muscles were reinnervated successfully by this procedure. CONCLUSIONS: If the RLN is infiltrated by DTC, immediate ACN-to-RLN anastomosis during complete excision of DTC could restore satisfactory phonatory function and does not compromise oncological radicality.

Sternothyroid receives a supplementary innervation separate to the ansa cervicalis: a case report of a variation.

We report on an additional innervation to the sternothyroid that, to our knowledge, has not been previously described. During a cadaveric neck dissection, we found an aberrant nerve to the sternothyroid in addition to the normal innervation. The classical innervation to the sternothyroid is through the ansa cervicalis (C1-C3), and the sternothyroid muscle is important for depression of the thyroid cartilage that is involved with swallowing and speech. The cervical plexus is difficult and time consuming to elucidate in fixed cadavers, which limits knowledge of variations from this source. Branches of the plexus are delicate and can be damaged during operations on the neck. Awareness of variations in innervation during operation reduces the chance of damage to nerves and prevents functional changes postoperatively.