Recurrent Nerve Research Articles

Case report: Successive ipsilateral and contralateral laryngeal nerve palsy as probable manifestation of neuroborreliosis

Neuroborreliosis is part of advanced stage of Lyme disease and often characterized by damage to the cranial and/or peripheral nerves. Involvement of one or both recurrent nerves is rare. Diagnosis is often difficult and based on a set of clinical manifestations, biological arguments, and cerebrospinal fluid (CSF) analysis. A 70-year-old man was referred to our Voice Clinic with a 3-month history of dysphonia caused by right vocal fold paralysis (VFP) without any cutaneous symptoms of tick bite or erythema migrans in the previous weeks and normal initial radiological examination (neck and thorax CT). Methylprednisolone had already been prescribed but without any clinical improvement. Late biological investigation 3 months after initial symptoms of VFP showed high IgG (93 U/mL; reference <10 U/mL) against Borrelia burgdorferi (BB), which was confirmed by two immunoblot markers (VIsE, p39 antigens). Therefore, a possible manifestation of Lyme disease with involvement of the right inferior laryngeal nerve was suspected, namely Lyme neuroborreliosis. However, given the spontaneous recovery of the patient after 7 months without any adapted antimicrobial regimen treatment, the diagnosis of neuroborreliosis was not confirmed by a lumbar puncture. Nineteen months later, the patient presented again for the same symptomatology but as left VFP. High IgG (68 U/mL) and IgM (>6, reference <0.90) levels against BB were confirmed by immunoblot. Subsequently, lumbar puncture was performed and revealed IgG against BB at 46.1 UA/mL (reference<5.5 UA/mL) in the CSF, with an extremely high IgG intrathecal synthesis antibody index (281.33, positive if > 1.5). Intrathecal antibody synthesis is the gold standard for Lyme neuroborreliosis demonstrating a specific immune response to BB in the central nervous system, but with the limitation of persistence for years after eradication. Our patient did not exhibit pleocytosis in the CSF. Therefore, two criteria of the European Federation of Neurological Societies (EFNS) guidelines are fulfilled for possible neuroborreliosis. Doxycycline treatment led to rapid recovery in less than 8 weeks and normal mobility of the left vocal fold. Because of this very uncommon clinical presentation with two successive episodes of VFP for no other obvious reason and serological evidence from the serum and CSF during the second episode, we consider it possible that the first episode of VFP could also have been a manifestation of neuroborreliosis. This case is the first report of possible relapse of laryngeal palsy successively on the right, and then the left side as a manifestation of Lyme neuroborreliosis.

Functional Electrical Stimulation (FES)—Therapeutical potentials for presbyphonia

Presbyphonia, an age-related decrease in voice quality is a consequence of vocal muscle atrophy. Functional Electrical Stimulation (FES) was introduced as a potential treatment to increase the muscle volume. In this study, we analyzed the effects of FES using ex vivo sheep larynx models. To stimulate the thyroarytenoid muscle, electrodes were implanted at the recurrent laryngeal nerve of 12 sheep (10 y). Stimulation was applied to six sheep for 9 weeks. Afterwards, the excised larynges were fixated in a mechanical setup and analyzed. For different elongations of the VFs, the acoustic signal, the subglottal pressure, and the VF motion were recorded simultaneously. The postprocessing was performed with the Glottis Analysis Tools (GAT) software and SPSS. The results show that the vibration characteristics and sound quality improved for the stimulated larynges. The vibration showed a higher degree of glottis closure (GGI) and symmetry (PAI and ASI), as well as a faster glottis closure (MADR) achieved by FES. Consequently, the sound signal exhibited a larger number of tonal sound components (CPP). Furthermore, a higher correlation between acoustic and subglottal pressure was found indicating an enhanced coupling between sub- and supraglottal regions. The results suggest that FES could be a possible therapy for presbyphonia.

Uncommon Cause of Recurrent Pneumonias

A patient who presented with sudden shortness of breath, stridor, and recurrent laryngeal nerve paralysis was diagnosed with a tracheal diverticulum. The diagnosis was established through CT scans and confirmed via endoscopy. Distinctive CT findings revealed an air-filled, tubular structure located behind and slightly to the right lateral of the trachea, which communicated with it. Endoscopy demonstrated a narrow-mouthed diverticulum originating from the posterior right wall of the trachea, approximately 8 cm below the level of the true vocal cords. Successful medical treatment was administered, and the patient experienced an uncomplicated recovery.

Intraoperative Neurophysiological Monitoring in Thyroid Operations as a Method of Reducing Neurological Deficit

Introduction. Intraoperative neuromonitoring consists in current stimulation of the laryngeal nerve located near the thyroid gland. The intensity is usually set in the range of 1–2 mA in order to give the desired effect, but also to give the selectivity of the controlled nerves. The charge is designed to stimulate the vocal cords and motor innervation within the larynx, especially in the area of tissues subjected to surgery.&#x0D; Aim. The aim of the study was to present intraoperative monitoring of the recurrent laryngeal nerve as a method of reducing the incidence of side effects associated with damage to the laryngeal nerve and to compare the quality of life of patients who were neuromonitored during procedures with those who underwent surgery without the use of intraoperative neuromonitoring.&#x0D; Material and Methods. The study was conducted in two research groups. The first group consisted of 100 patients from CentroMedica Sp. z o. o. from all over Poland, who underwent surgery to remove a thyroid tumor with the help of neuromonitoring. The second research group consisted of 100 patients of the same company. They also underwent thyroid tumor excision, but in their case without the use of neuromonitoring. In the study described in this paper, the diagnostic survey method was used using the HAQ health questionnaire and the analysis of medical records.&#x0D; Results. In patients after procedures without the use of intraoperative monitoring, postoperative complications were observed more often than in patients with monitoring. Patients after procedures without neuromonitoring more often had hoarseness as a complication after the procedure.&#x0D; Conclusions. Based on the conducted research, it can be concluded that intraoperative neuromonitoring during thyroid surgery has an impact on the better quality of life of patients after surgery. (JNNN 2023;12(3):112–119)

Robotic esophagectomy with outermost layer-oriented dissection for esophageal cancer: technical aspects and a retrospective review of a single-institution database.

Systematic lymph node dissection in patients with gastric cancer could be sufficiently and reproducibly achieved along the outermost layer of the autonomic nerves and similar concept has been extensively used for robotic esophagectomy (RE) since 2018. This study aimed to determine the surgical and oncological safety of RE using the outermost layer-oriented approach for esophageal cancer (EC). Sixty-six patients who underwent RE with total mediastinal lymphadenectomy for primary EC between April 2018 and December 2021 were retrospectively reviewed. All underwent the outermost layer-oriented approach with intraoperative nerve monitoring (IONM). Postoperative complications within 30 days were analyzed. Among the patients, 51 (77.3%) were male. The median age was 64 years, and the body mass index was 21.8 kg/m2. Furthermore, 58 (87.9%) patients had squamous cell carcinoma and eight (12.1%) patients had adenocarcinoma. Clinical stages I, II, and III were seen in 23 (34.8%), 23 (34.8%), and 16 (24.2%) patients, respectively. Thirty-four (51.5%) patients received preoperative treatment. No patient shifted to conventional thoracoscopic or open procedure intraoperatively. The median operative time was 716 min with 119 mL of blood loss. Additionally, 64 (97%) patients underwent R0 resection. The morbidity rates based on Clavien-Dindo grades ≥ II and ≥ IIIa were 30.3% and 10.6%, respectively, within 30 postoperative days. None died within 90 days postoperatively. Three (4.5%) patients exhibited recurrent laryngeal nerve (RLN) palsy (CD grade ≥ II). The sensitivity and specificity of IONM for RLN palsy were 50% and 98.3% at the right RLN and 33.3% and 98.0% at the left RLN, respectively. RE with the outermost layer-oriented approach can provide safe short-term outcomes.

Diagnosis and Open Surgical Management of Laimer's Diverticulum: Case Series and Review of the Literature.

Objectives: Laimer's diverticulum (LD) is a very rare clinical entity originating between the cricopharyngeus muscle (CPM) and circular muscular fibers of the esophagus. Its diagnosis and management remain to be elucidated. This article summarizes our experience in its diagnosis and open surgical management.Methods: A retrospective review of LD cases treated at our tertiary medical institution was conducted between July 2018 and May 2023. The clinical and demographic data were retrieved from case notes.Results: Three cases were included in this review. There were 2 male patients and 1 female patient. The average and median ages were 47.3 and 54 years, respectively. Presenting symptoms included hoarseness, pharyngeal foreign body sensation, and neck mass. All 3 diverticula were on the left side, with the first 2 cases discovered accidentally on gastric endoscopic or cervical MRI examinations. After evaluating esophageal swallowing with barium sulfate or urografin contrast media, all the patients consented to undergo an open surgical procedure. During surgical exploration, the diverticula were found to be on the posterior part of the cervical esophagus, below CPM, and away from the recurrent laryngeal nerve, and only then, could the diagnosis of LD be established. Then, diverticulectomy and manual suturing of the esophagus was performed. Recovery of all 3 patients was uneventful. Nasogastric tube feeding lasted 7 to 12 days until esophageal examinations demonstrated no leak, and then, oral liquid feeding resumed. The median duration of follow-up was 50 months. No recurrence of symptoms or diverticulum was observed, and the swallowing function of all 3 patients was excellent.Conclusions: An open surgical approach is not only important for the diagnosis of LD, but can also be utilized as a safe and effective treatment.

Pediatric Unilateral Vocal Fold Paralysis

Purpose: The aim of this case study was to provide a review of a pediatric patient diagnosed with unilateral vocal fold paralysis. Method: The case history, voice samples, laryngeal examinations, and diagnostic probes were reviewed in a 10-year-old girl with the chief complaint of persistent dysphonia, characterized by use of both a breathy and a typical voice. Perceptual ratings were completed using both Consensus Auditory-Perceptual Evaluation of Voice and Grade, Roughness, Breathiness, Asthenia, and Strain scales. Cepstral peak prominence was determined and compared for the same file segment using both Praat and Analysis of Dysphonia in Speech and Voice analysis programs. Treatment probes during the initial preoperative visit are described. Results: The patient was able to compensate for short phonation tasks, but longer conversations were judged to have increased dysphonia and increased vocal fatigue. Because noted compensation was unable to be stabilized or sustained, both a reinnervation of the ansa cervicalis to the recurrent laryngeal nerve and voice therapy techniques were recommended as part of the multidisciplinary team plan. Conclusion: Pediatric patients with unilateral vocal fold paralysis may present with complex phonatory behaviors. This case study paired with supplemental acoustic and videostroboscopy files provides an opportunity to practice both an auditory-perceptual and acoustic assessment and to rate a laryngeal examination. Supplemental Material: https://doi.org/10.23641/asha.24163926

Intraoperative Neuromonitoring Does Not Reduce the Risk of Temporary and Definitive Recurrent Laryngeal Nerve Damage during Thyroid Surgery: A Systematic Review and Meta-Analysis of Endoscopic Findings from 73,325 Nerves at Risk.

While intraoperative neuromonitoring (IONM) helps the early identification of recurrent laryngeal nerve (RLN) damage, IONM's role in RLN damage prevention is not defined, given the lack of large studies on the subject. In a PRISMA-compliant framework, all original thyroid surgery prospective studies providing early postoperative endoscopic data for all patients were pooled in a random-effects meta-analysis. We compared the temporary (and definitive where available) RLN damage rates according to IONM use and IONM type (intermittent, I-IONM, or continuous, C-IONM). We identified 2358 temporary and 257 definitive RLN injuries in, respectively, 73,325 and 66,476 nerves at risk. The pooled temporary and definitive RLN injury rates were, respectively, 3.15% and 0.422% considering all procedures, 3.29% and 0.409% in cases using IONM, and 3.16% and 0.463 in cases not using IONM. I-IONM and C-IONM, respectively, showed a pooled temporary RLN injury rate of 2.48% and 2.913% and a pooled definitive injury rate of 0.395% and 0.4%. All pooled rates had largely overlapping 95% confidence intervals. Our data suggest that IONM does not affect the temporary or definitive RLN injury rate following thyroidectomy, though its use can be advised in selected cases and for bilateral palsy prevention.

Diagnostic Accuracy of Laryngeal Ultrasound for Evaluating Vocal Fold Movement Impairment in Children

PurposeVocal fold movement impairment (VFMI) secondary to recurrent laryngeal nerve (RLN) injury is a common source of morbidity after pediatric cervical, thoracic, and cardiac procedures. Flexible laryngoscopy (FL) is the gold standard to diagnose VFMI yet can be challenging to perform and/or risks possible clinical decompensation in some children and is an aerosolizing procedure. Laryngeal ultrasound (LUS) is a potential non-invasive alternative, but limited data exists in the pediatric surgical population regarding its efficacy. We aimed to investigate the diagnostic accuracy of LUS compared to FL in evaluating VFMI. MethodsA prospective, single-center, single-blinded (rater) cohort study was undertaken on perioperative pediatric patients at risk for RLN injury. Patients underwent FL and LUS. Cohen's kappa was used to determine chance-corrected agreement. ResultsBetween 2021 and 2023, 85 paired evaluations were performed with patients having a median (IQR) age of 10 (4, 42) months and weight of 7.5 (5.4, 13.4) kilograms. The prevalence of VFMI was 27.1%. Absolute agreement between evaluations was 98.8% (kappa 0.97, 95% CI: 0.91–1.00, P < 0.001). The sensitivity and specificity of LUS in detecting VFMI was 95.7% and 100%, yielding a positive predictive value (PPV) of 100% and negative predictive value (NPV) of 98.4% (95% CI: 90–100%). Diagnostic accuracy was 98.8% (95% CI: 93–100%). ConclusionLUS is a highly accurate modality in evaluating VFMI in children. While FL remains the gold standard for diagnosis, LUS offers a low-risk screening modality for children at risk for VFMI such that only those with an abnormal LUS or presence of clinical symptoms discordant with LUS findings should undergo FL. Type of StudyProspective, single-center, single blinded (rater), cohort study. Level of EvidenceLevel II.

The Presence of an Arteria Lusoria Should Be Checked When Reporting 18 F-FCH PET/CT Performed to Localize Hyperfunctioning Parathyroid Glands.

Nonrecurrent inferior laryngeal nerve (NRILN) is a rare anatomical variant, which significantly increases the risk of nerve injury during neck surgery, for example, thyroidectomy or parathyroidectomy (PTX). The absence of the brachiocephalic trunk and presence of arteria lusoria (AL) are strong predictors of NRILN in the right neck. FCH PET/CT is now a recognized imaging modality in hyperparathyroidism (HPT). We report 2 patients with primary or renal HPT in whom FCH PET detected right HFPTs and low-dose noncontrast CT evidenced AL. The NRILN was thus preserved during PTX. We recommend searching for AL on FCH PET/CT (even low-dose) in HPT before PTX.

Gasless Endoscopic Thyroidectomy via the Trans-Axillary Approach.

For patients with early, low-risk papillary thyroid carcinoma, an increasing number are opting for endoscopic thyroid surgery due to its ability to achieve favorable therapeutic outcomes while maintaining excellent cosmetic results. Among the available endoscopic procedures, the Gasless Endoscopic Thyroidectomy Trans-axillary Approach (GETTA) has gained popularity among surgeons. This is attributed to its straightforward cavity construction, spacious operating area, precise visual field exposure, and manageable learning curve. However, few studies have provided detailed descriptions of the specific surgical steps involved in GETTA. Drawing from a synthesis of existing literature and our own clinical expertise, we present a comprehensive outline of the GETTA procedure. This process can be categorized into five distinct stages: positioning and incision planning; establishment of surgical cavities; identification and protection of the recurrent laryngeal nerve, inferior parathyroid gland, and central neck dissection; localization and preservation of the superior laryngeal nerve, superior parathyroid gland, and dissection of the thyroid's superior pole; transection of the thyroid isthmus followed by en bloc resection of the thyroid gland and central neck lymph nodes. The five-step approach of GETTA is easy to learn and can be adapted for resecting both benign and malignant thyroid and parathyroid diseases.

Comparison of Clinical Efficacy Between Da Vinci Robot-Assisted Ivor Lewis Esophagectomy and McKeown Esophagectomy for Middle and Lower Thoracic Esophageal Cancer: A Multicenter Propensity Score-Matched Study.

We compared the perioperative efficacy and safety of da Vinci robot-assisted Ivor Lewis esophagectomy and McKeown esophagectomy for middle and lower thoracic esophageal cancer. A retrospective case-control study method was used. A total of 181 patients with esophageal cancer admitted to three medical centers in China from February 2018 to October 2022 were collected and divided into two groups according to surgical method: da Vinci robot-assisted thoracic surgery (RATS) Ivor Lewis esophagectomy (Ivor Lewis group) and RATS McKeown esophagectomy (McKeown group), respectively. Propensity score matching (PSM) analysis was used to reduce selection bias caused by confounding factors. The perioperative indicators of the two groups were compared and analyzed. There was a statistically significant difference in age and tumor location between the Ivor Lewis group and the McKeown group. After PSM, the above factors were no longer statistically significant. There were 80 patients in each group after PSM. In terms of operative time (P = 0.005), anastomotic leakage (P = 0.029), and pulmonary infection (P = 0.035), the Ivor Lewis group has significant advantages; in terms of the number of lymph nodes dissected around the recurrent laryngeal nerve (P = 0.010), the McKeown group has significant advantages. Both RATS Ivor Lewis esophagectomy and McKeown esophagectomy are safe and effective for treatment of middle and lower thoracic esophageal cancer. Ivor Lewis has advantages in operative time, anastomotic leakage, and pulmonary infection, while McKeown has advantage in lymph node dissection around the recurrent laryngeal nerve.

Atrophy of the Posterior Cricoarytenoid Muscle as an Indicator of a Recurrent Laryngeal Nerve Injury History Before Revision Anterior Cervical Spine Surgery.

Retrospective study. In our recent study, we observed some cases of symptomatic normal vocal cord motility instead of asymptomatic vocal cord palsy (VCP) in preoperative laryngoscopy of a revision anterior cervical spine surgery (ACSS) cohort. We assumed the intrinsic muscle atrophy caused by recurrent laryngeal nerve injury could cause vocal cord-related symptoms. Thus, radiological examinations were reviewed in relation to the posterior cricoarytenoid (PCA) muscle, one of the intrinsic muscles. We retrospectively analyzed 64 patients who underwent a revision ACSS. Patients with vocal cord-related symptoms were classified as symptomatic group (group S, n = 11), and those without symptoms as asymptomatic group (group AS, n = 53). The bilateral size and signal intensity of the PCA muscles in these patients were measured in the axial view with preoperative computed tomography (CT) and magnetic resonance imaging (MRI) evaluations. Since the size and signal intensity values were different on each image, the ratios of the contralateral and ipsilateral muscle values were analyzed for each modality. There was no VCP on laryngoscopy study. However, the mean ratio of the PCA muscle size on CT was 1.40 ± .37 in group S and 1.02 ± .12 in group AS (P = .007). These values on the MRI were 1.49 ± .45 in group S and 1.02 ± .14 in group AS, which was also a significant difference (P = .008). Evaluating the size of the PCA muscle before revision ACSS may predict a previous recurrent laryngeal nerve injury. Careful planning for the appropriate approach should be undertaken if vocal cord-related symptoms and atrophy of PCA muscle are evident.

Application of overlap anastomosis in digestive tract reconstruction during minimally invasive Ivor-Lewis esophagectomy.

This study aims to assess the feasibility of the Overlap anastomosis technique in minimally invasive Ivor-Lewis esophagectomy. An accompanying video presentation elucidates our surgical procedures. A retrospective review of 46 patients diagnosed with middle and lower esophageal cancer was conducted. These patients underwent minimally invasive Ivor-Lewis esophagectomy with Overlap anastomosis between January 2019 and December 2020. A consistent team of surgeons performed all procedures. The initial phase involved laparoscopic stomach mobilization, intra-abdominal lymphadenectomies, and preparation of the tubular stomach. Subsequently, with the patient in the left decubitus position, thoracoscopy was used to dissect the esophagus, excise the diseased segment, and conduct mediastinal lymph node dissection. The final stage encompassed the intrathoracic gastroesophageal anastomosis using the Overlap method. All surgeries were completed without converting to an open approach, achieving complete resection. There were no operative fatalities, with an average surgery duration of 259.4min. Average statistics included intraoperative blood loss of 92.3ml, 16.2 lymph nodes dissected, and a postoperative hospital stay of 10.3days. Postoperative complications comprised three instances of hoarseness due to recurrent laryngeal nerve palsy, two cases of aspiration pneumonia, one occurrence of chylothorax, and one gastric emptying disorder. Anastomotic technique-related complications were minimal, with only one patient experiencing an anastomotic leak that resolved spontaneously and two patients facing anastomotic stenosis, which was subsequently alleviated. Our findings posit that the Overlap anastomosis method is safe and efficient for minimally invasive Ivor-Lewis esophagectomy, marked by a notably low rate of anastomosis-related complications. Further evaluation of its long-term implications remains necessary.

Return of Vocal Fold Motion and Surgical Preservation of Invaded Recurrent Laryngeal Nerves After the Use of Neoadjuvant Therapy in Patients Presenting with Advanced Thyroid Cancer and Vocal Fold Paralysis: The Lazarus Effect.

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Reconstruction of Vocal Fold Medial Surface 3D Trajectories: Effects of Neuromuscular Stimulation and Airflow.

Analysis of medial surface dynamics of the vocal folds (VF) is critical to understanding voice production and treatment of voice disorders. We analyzed VF medial surface vibratory dynamics, evaluating the effects of airflow and nerve stimulation using 3D reconstruction and empirical eigenfunctions (EEF). In vivo canine hemilarynx phonation. An in vivo canine hemilarynx was phonated while graded stimulation of the recurrent and superior laryngeal nerves (RLN and SLN) was performed. For each phonatory condition, vibratory cycles were 3D reconstructed from tattooed landmarks on the VF medial surface at low, medium, and high airflows. Parameters describing medial surface trajectory shape were calculated, and underlying patterns were emphasized using EEFs. Fundamental frequency and smoothed cepstral peak prominence (CPPS) were calculated from acoustic data. Convex-hull area of landmark trajectories increased with increasing flow and decreasing nerve activation level. Trajectory shapes observed included circular, ellipsoid, bent, and figure-eight. They were more circular on the superior and anterior VF, and more elliptical and line-like on the inferior and posterior VF. The EEFs capturing synchronal opening and closing (EEF1) and alternating convergent/divergent (EEF2) glottis shapes were mostly unaffected by flow and nerve stimulation levels. CPPS increased with higher airflow except for low RLN activation and very dominant SLN stimulation. We analyzed VF vibration as a function of neuromuscular stimulation and airflow levels. Oscillation patterns such as figure-eight and bent trajectories were linked to high nerve activation and flow. Further studies investigating longer sections of 3D reconstructed oscillations are needed. N/A, Basic Science Laryngoscope, 134:1249-1257, 2024.

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

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. 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. 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. 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.

Vocal Cord Paralysis after Repair of Esophageal Atresia.

Etiology of vocal cord paralysis (VCP) and laryngeal dysfunction may be congenital or surgical trauma of recurrent and superior laryngeal nerves. We assessed the incidence, risk factors, and morbidity of VCP after repair of esophageal atresia (EA). Medical records of 201 EA patients from 2000 to 2022 were reviewed for this retrospective study. Postrepair vocal cord examination (VCE) included awake nasolaryngeal fiberoscopy by otolaryngologist or laryngoscopy under spontaneous breathing anesthesia. Before 2017, postoperative VCE was performed in symptomatic patients only and routinely after 2017. Overall, VCE was performed on 79 (38%) patients (52 asymptomatic), whereas 122 asymptomatic patients underwent no VCE. VCP was diagnosed in 32 of 79 patients (right 12, left 10, and bilateral 10; symptomatic 25 and asymptomatic unilateral 7) corresponding with extrapolated overall VCP incidence of 16 to 24% among 201 patients including asymptomatic ones. Ten patients (bilateral VCP 8 and left VCP 2) required tracheostomy. Of 10 patients with bilateral VCP, three underwent laryngotracheal expansion surgery (left VC lateralization in one and laryngoplasty in two with acquired subglottic stenosis), three remained tracheostomy dependent, three were off tracheostomy, and one died of complications after redo esophageal reconstruction. All patients with unilateral VCP managed without tracheostomy. Cervical dissection or ostomy formation was a major risk factor of VCP. Repair of EA is associated with a considerable risk of VCP and associated morbidity. Cervical EA surgery significantly increased the risk of VCP. Bilateral VCP may eventually require laryngotracheal expansion surgery.

Unexpected mapping of recurrent laryngeal nerve by fluorescence-guided surgery using near-infrared indocyanine green angiography

Background. The recurrent laryngeal nerve (RLN) damage and parathyroid gland injury are the most severe complications of thyroid surgery. The possibility of RLN confirmation in the near-infrared spectrum after the injection of indocyanine green (ICG) was not yet been studied. Aim: to evaluate the ICG angiography for the identification of RLN during thyroid and parathyroid surgery. Materials and methods. ICG angiography of RLN was performed in 7 patients. An intraoperative neuromonitoring was applied as a method of controlling RLN. During the operation, parathyroid glands and RLN were identified by visual inspection (naked eye). To further confirm the location of the parathyroid glands by autofluorescence, an intravenous injection of ICG was performed with a concentration of 0.25 mg/kg followed by the application of the image-based system. Results. A good signal was achieved in the near-infrared spectrum from the RLN in all cases after the ICG injection. Sufficient blood perfusion of the RLN could be considered as a reasonable explanation for the exhibition of a good ICG near-infrared signal. Conclusions. ICG use might be a helpful approach for the confirmation of the RLN in addition to routine visual identification. Such function could be applied during fluorescence-guided surgery to evaluate the parathyroid gland autofluorescence. Visualization of RLN by ICG angiography is considered as an additional useful feature to prevent RLN injury.

Accelerometry May be Superior to EMG for Early Evaluation of Vocal Cord Function After Nerve Injury in a Pig Model.

Vocal cord (VC) movement has been demonstrated by the use of accelerometry (ACC) to decrease in parallel with the electromyographic amplitude (EMG) during ongoing traction injury to the recurrent laryngeal nerve (RLN). When RLN function recovers, discrepancies between EMG and VC movement have been reported in clinical and experimental studies. The present study was conducted to clarify the actual relationship between EMG and VC movement measured by ACC during nerve recovery. EMG obtained by continuous nerve monitoring (C-IONM) was compared with ACC during traction injury to the RLN, and throughout 40-min nerve recovery. A three-axis linear accelerometer probe was attached to the VC, and ACC data were registered as described. Traction damage was applied to the RLN until there was a 70% amplitude decrease from baseline EMG, or until loss of signal (LOS), that is, EMG values ≤100 μV. Thirty-two RLN from 16 immature pigs were studied. Correlation between EMG and ACC were calculated during nerve injury and nerve recovery. The mean correlations were for the 70% and LOS group from start to end of traction: 0.82 (±0.17) and 0.87 (±0.17), respectively. Corresponding correlation coefficients during 40-min recovery was 0.50 (±0.48) in the 70% group and 0.53 (±0.33) in the LOS group. There is a high correlation between EMG and VC movement during nerve injury, and a moderate correlation during early nerve recovery. EMG recovery after RLN injury ensures sufficient VC function as assessed by ACC. N/A Laryngoscope, 134:1485-1491, 2024.