Chondronecrosis of the cricoid treated with hyperbaric oxygen therapy: A case series.

We present two cases of cricoid chondronecrosis treated with hyperbaric oxygen (HBO2) therapy. Both patients presented with biphasic stridor and dyspnea several weeks after an intubation event. Tracheostomy was ultimately performed for airway protection, followed by antibiotic treatment and outpatient HBO2 therapy. Both patients were decannulated within six months of presentation and after at least 20 HBO2 therapy sessions. Despite a small sample size, our findings are consistent with data supporting HBO2 therapy's effects on tissue edema, neovascularization, and HBO2 potentiation of antibiotic treatment and leukocyte function. We suggest HBO2 therapy may have accelerated airway decannulation by way of infection resolution as well as the revitalization of upper airway tissues, ultimately renewing the structural integrity of the larynx. When presented with this rare but significant clinical challenge, physicians should be aware of the potential benefits of HBO2 therapy.

Reinke's Edema and Risk Factors, A Case-Control Study.

Reinke's edema (RE) is a benign pathological non-inflammatory disorder of the vocal folds with a wide range of clinical manifestations. We aim to investigate the relationship between Reinke's edema and some common inhalant abuse. In this case-control study, subjective consisted of 23 patients with RE (the cases), and 50 patients with sinusitis (control) who underwent surgery in the Department of Otolaryngology, between 2015 and 2020. Demographic characteristics, history of some related disease, methods, and the duration of cigarette, and opium consumption were collected through the patients' files. The chi-square (χ²) test was run to analyze the differences in the categorical and, and the Independent Sample T-test was used to compare two sample means from unrelated groups. A significant level (p-value) was considered less than 0.05. The mean age was 54 ± 12 years, and 42 ± 11 years, respectively for Reinke's edema and sinusitis. More women had been recorded in the RE group, compared to men. Allergy, unprincipled use of voice and talkativeness, history of laryngeal surgery, and type of disease were correlated to RE (p < 0.05). Also, cigarette smoking was significantly correlated with Reinke's edema. The average number of cigarettes per day, the duration of smoking, and opium consumption were more frequent in RE (P < 0.05). 90% of the RE and 4% of sinusitis patients were opium consumers. There was a statistically significant difference in the methods of substance use in the two groups of cases and control (p < 0.0001). Among the different methods, the poker and stone method was the most common (69.6%), and the opium smoking pipe was the second most common method. This study also confirmed the hazardous effects of smoking and inhaling opiates in the formation of lesions of the pharynx and larynx. In particular, longer use of these substances will be associated with more serious side effects. Therefore, it seems that people who are addicted to opiates should undergo periodic visits and counseling to reduce and stop their use.

What kind of phonation causes the strongest vocal fold collision? - A hemi-larynx phonation contact pressure study.

This paper presents a measurement setup which is able to measure the distribution of small scale pressure on an area of 15.2 mm × 30.4 mm with a sample rate up to 1.2 kHz. It was used to investigate the contact pressures of vocal folds during phonation. This was performed in ex vivo experiments of 11 porcine larynges. The contact pressure at the medial surface and other phonation parameters, as the glottal resistance and the closing velocity of the vocal fold, were measured at different adduction and elongation levels and air flow rates. A statistical analysis was carried out. It could be shown that the contact pressure rises, when the vocal fold is manipulated or when the flow rate is increased.

Analysis of local, regional, and distant recurrence of disease in mucoepidermoid tumors of larynx: A systematic review.

The aim of this systematic review is to analyze epidemiology, clinical presentation, histopathological features, treatment and oncological outcomes in laryngeal mucoepidermoid cancer (MEC) in order to improve the knowledge on the management of such a rare malignant neoplasm. Specifically, authors highlight patients' and tumors' features about local, regional, and distant recurrence of disease. PRISMA 2020 guidelines were applied in this systematic literature review. A computerized search was performed using the Embase/Pubmed, Scopus, and Cochrane databases, for articles published from 1971 to December 2023. A descriptive and univariate analysis including selected papers with low or intermediate risk of bias was performed. Twenty-seven papers (11 case series and 16 case reports) were included in this review. Fifty-six patients were included in the analyses, with a mean age of 56.7 years; 84% of them were males. Most patients (86%) underwent a primary surgical approach. Clinical stage was reported as follows: early stage (26 patients) and locally advance and advanced stage (19 patients). Overall survival (OS) and disease-free survival (DFS) at 2 years was 80% and 78%, respectively. The mean time to local recurrence was 18.7 months (range 8-36 months). The survival after recurrence is about 85% and 70% at 5 years, respectively. The mean time of lymph node recurrence was 14.7 months (range 7-19 months). Finally, the mean time of distant recurrence was 15 months (range 7-36 months) with a poor prognosis: all patients died due to the disease in a range of 0-7 months after metastasis evidence. Laryngeal MEC is a rare neoplasm of minor salivary glands in the larynx. No guidelines or indications about the management of this neoplasm are reported in the literature. The lower incidence of regional recurrence of the disease and the better OS and DFS underline how the prognosis of MEC is more favorable respect to other malignant histotypes.

Catch my drift? Between-farm dispersal of biofouling waste from salmon pen net cleaning: Potential risks for fish health.

Biofouling is a serious challenge for global salmon aquaculture and farmers have to regularly clean pen nets to avoid impacts on stock health and farms' structural integrity. The removed material is released into the surrounding environment. This includes cnidarian species such as hydroids, whose nematocyst-bearing fragments can impact gill health and fish welfare. There is also increasing evidence of the association of parasites and pathogens with biofouling organisms and cleaning fragments. It is unknown whether and how far local current regimes disperse biofouling material and whether this material reaches and interacts with adjacent pens or even neighbouring farms downstream, or wild fish populations in surrounding environments. We focussed on the cnidarian hydroid Ectopleura larynx, one of the most abundant biofouling species on Norwegian aquaculture installations. Using a 3D hydrodynamic model parameterised with physical and biological properties of hydroid particles (derived via field and laboratory studies), we simulated the dispersal of net cleaning waste from two Norwegian salmon farms. Our results demonstrate that net cleaning waste is extensively dispersed throughout neighbouring pens, and even to adjacent aquaculture facilities. Salmon were exposed to concentrations of biofouling particles up to 41-fold elevated compared to background concentrations, and for up to 30.5 h. Maximum dispersal distance of hydroid particles was 5.5 km from the point of release, achieved largely within 48 h. Least-cost distance calculations show that this distance exceeds the nearest-neighbour distance of 70 % of Norway's salmon farms (654 farms). Our study provides some evidence that actions taken to manage biofouling at salmon farms may affect neighbouring farms and surrounding natural environments. The results highlight the potential risks associated with net cleaning: the dispersal of harmful cnidarian particles, associated pathogens, and non-indigenous species, thus underlining the need for novel farming or net cleaning technologies that prevent the release of potentially harmful cleaning waste.

Fatal cerebritis and ventriculitis secondary to tracheoesophageal prosthesis.

Tracheoesophageal puncture and voice prosthesis placement is the preferred method of voice restoration following total laryngectomy. Although this is a safe and effective means of optimizing voice, severe complications can occur. We present the case of a patient who developed cerebritis and ventriculitis secondary to a tracheoesophageal prosthesis eroding his cervical vertebrae 20 years following pharyngo-laryngo-esophagectomy. Despite optimal antimicrobial therapy, he deteriorated and succumbed to his disease. Although tracheoesophageal prostheses are a safe and effective means of voice restoration, life-threatening complications can occur. This case report highlights a rare but severe case of cervical osteomyelitis, epidural abscess, and cerebritis and ventriculitis secondary to tracheoesophageal prosthesis. Clinicians must be aware of this severe complication in postlaryngectomy patients with tracheoesophageal prostheses.

Laryngeal Ganglioneuromatosis in a Child With Multiple Endocrine Neoplasia Type 2B (MEN2B): Case Report and Review of Literature.

Multiple Endocrine Neoplasia type 2B (MEN2B) is an autosomal dominant cancer syndrome caused by a mutation in rearranged during transfection (RET) proto-oncogene and includes medullary thyroid carcinoma, pheochromocytoma, gastrointestinal neuromas, and mucosal ganglioneuromas. Medullary thyroid carcinoma is the major cause of mortality in MEN2B syndrome. Medullary thyroid carcinoma can often appear during the first years of life. While mucosal neuromas in MEN2B are common, laryngeal neuromas are extremely rare. We present a third case of a pediatric patient with a laryngeal neuroma localized to the left true vocal cord and conduct a literature review of vocal cord neuromas in MEN2B patients.

Drug delivery systems for wound healing treatment of upper airway injury.

INTRODUCTION: Endotracheal intubation is a common procedure to maintain an open airway with risks for traumatic injury. Pathological changes resulting from intubation can cause upper airway complications, including vocal fold scarring, laryngotracheal stenosis, and granulomas and present with symptoms such as dysphonia, dysphagia, and dyspnea. Current intubation-related laryngotracheal injury treatment approaches lack standardized guidelines, relying on individual clinician experience, and surgical and medical interventions have limitations and carry risks. AREAS COVERED: The clinical and preclinical therapeutics for wound healing in the upper airway are described. This review discusses the current developments on local drug delivery systems in the upper airway utilizing particle-based delivery systems, including nanoparticles and microparticles, and bulk-based delivery systems, encompassing hydrogels and polymer-based approaches. EXPERT OPINION: Complex laryngotracheal diseases pose challenges for effective treatment, struggling due to the intricate anatomy, limited access, and recurrence. Symptomatic management often requires invasive surgical procedures or medications that are unable to achieve lasting effects. Recent advances in nanotechnology and biocompatible materials provide potential solutions, enabling precise drug delivery, personalization, and extended treatment efficacy. Combining these technologies could lead to groundbreaking treatments for upper airways diseases, significantly improving patients' quality of life. Research and innovation in this field are crucial for further advancements.

Extraskeletal Ewing's sarcoma of supraglottis: A rare case report.

Ewing's Sarcoma family of tumors is a group of small round tumor cells. Ewing's sarcoma majority occurs in bone, accounts about 10 % of primary bone tumors. Extraskeletal Ewing's sarcoma (ESS) is unusual and commonly seen in trunk, paravertebral, and chest wall region. It is rarely seen in head and neck region, accounting to 2-3 %. In head and neck region, ESS is seen in nasal or oral cavities, sinuses. EES originating in the larynx is very rare. Here, we report a 22 years old female having the complaints of change in voice and noisy breathing who was diagnosed as a case of EES of supraglottis. As the disease progressed during the time of diagnosis, she had to undergo emergency tracheostomy. The disease was inoperable so she received neoadjuvant chemotherapy followed by radiation followed by adjuvant chemotherapy. At present she is symptomatically better. The aim of this report is to put forward the rare site of Ewing's Sarcoma and highlighting the early diagnosis in suspected case with IHC, providing effective multimodality treatment.

Mechanisms of Swallowing, Speech and Voice Disorders in Parkinson's Disease: Literature Review with Our First Evidence for the Periperal Nervous System Involvement.

The majority of patients with Parkinson's disease (PD) develop swallowing, speech, and voice (SSV) disorders. Importantly, swallowing difficulty or dysphagia and related aspiration are life-threatening conditions for PD patients. Although PD treatments have significant therapeutic effects on limb motor function, their effects on SSV disorders are less impressive. A large gap in our knowledge is that the mechanisms of SSV disorders in PD are poorly understood. PD was long considered to be a central nervous system disorder caused by the death of dopaminergic neurons in the basal ganglia. Aggregates of phosphorylated α-synuclein (PAS) underlie PD pathology. SSV disorders were thought to be caused by the same dopaminergic problem as those causing impaired limb movement; however, there is little evidence to support this. The pharynx, larynx, and tongue play a critical role in performing upper airway (UA) motor tasks and their dysfunction results in disordered SSV. This review aims to provide an overview on the neuromuscular organization patterns, functions of the UA structures, clinical features of SSV disorders, and gaps in knowledge regarding the pathophysiology underlying SSV disorders in PD, and evidence supporting the hypothesis that SSV disorders in PD could be associated, at least in part, with PAS damage to the peripheral nervous system controlling the UA structures. Determining the presence and distribution of PAS lesions in the pharynx, larynx, and tongue will facilitate the identification of peripheral therapeutic targets and set a foundation for the development of new therapies to treat SSV disorders in PD.

Total laryngectomy vs. non-surgical organ preservation in advanced laryngeal cancer: a metanalysis.

OBJECTIVE: To compare the oncological results and the functional outcomes of patients undergoing Total Laryngectomy (TL) with the non-surgical treatment (organ preservation protocol) in the treatment of advanced laryngeal carcinomas through systematic review and meta-analysis. METHODS: A literature survey strategy was employed in order to perform a systematic review of the available evidence. Success rate and functional outomes after oncological treatment of patients with advanced laryngeal carcinomas was evaluated through systematic review and metanalysis, comparing TL and organ preservation protocol. RESULTS: The surgical treatment was associated with better survival outcomes. When stratifying by T stage, while patients with T4 staging have less risk of mortality with TL, there is no difference between the different treatments for patients with T3 tumors. Surgery is related to a lower chance of recurrence, late dysphagia and feeding tube dependence. CONCLUSION: Patients with T4 tumors should undergo TL as their treatment of choice. For patients with T3 tumors, there is no differences on the risk of mortality according to the therapeutic option, however, there is a greater chance of recurrence and dysphagia when surgery is not performed.

Treatment discordance in the utilization of neck dissection for stage I-II supraglottic tumors.

BACKGROUND: In 2018, the National Comprehensive Cancer Network treatment guidelines began recommending the use of neck dissection during surgical management of stage I-II supraglottic laryngeal squamous cell carcinoma (LSCC). METHODS: Trends and factors associated with the use of neck dissection during larynx-preserving surgery for patients with cT1-2, N0, M0 supraglottic LSCC in the National Cancer Database (2004-2020) were evaluated using multivariable-adjusted logistic regression. RESULTS: Of the 2080 patients who satisfied study eligibility criteria, 633 (30.4%) underwent neck dissection. Between 2018 and 2020, the rate of neck dissection was 39.0% (114/292). After multivariable adjustment, academic facility type, undergoing biopsy prior to surgery, and more radical surgery were significant predictors of receiving neck dissection. CONCLUSIONS: The results of this national analysis suggest that the utilization of guideline-concordant neck dissection for management of stage I-II supraglottic LSCC remains low and highlight the need to promote the practice of neck dissection for this patient population.

Lentiviral expression of wild-type LAMA3A restores cell adhesion in airway basal cells from children with epidermolysis bullosa.

The hallmark of epidermolysis bullosa (EB) is fragile attachment of epithelia due to genetic variants in cell adhesion genes. We describe 16 EB patients treated in the ear, nose, and throat department of a tertiary pediatric hospital linked to the United Kingdom's national EB unit between 1992 and 2023. Patients suffered a high degree of morbidity and mortality from laryngotracheal stenosis. Variants in laminin subunit alpha-3 (LAMA3) were found in 10/15 patients where genotype was available. LAMA3 encodes a subunit of the laminin-332 heterotrimeric extracellular matrix protein complex and is expressed by airway epithelial basal stem cells. We investigated the benefit of restoring wild-type LAMA3 expression in primary EB patient-derived basal cell cultures. EB basal cells demonstrated weak adhesion to cell culture substrates, but could otherwise be expanded similarly to non-EB basal cells. In vitro lentiviral overexpression of LAMA3A in EB basal cells enabled them to differentiate in air-liquid interface cultures, producing cilia with normal ciliary beat frequency. Moreover, transduction restored cell adhesion to levels comparable to a non-EB donor culture. These data provide proof of concept for a combined cell and gene therapy approach to treat airway disease in LAMA3-affected EB.

Spontaneous longitudinal rupture of the thyroid cartilage: A management of the rare clinical case.

INTRODUCTION AND IMPORTANCE: Non-traumatic rupture or other injuries to the larynx are very rare disorder. According to the published series, there are only 15 cases reported with such kind of injury to the larynx. Despite the rarity of the non-traumatic larynx fracture, it is important to elucidate adequate management for the patients with such emergency. The aim of the study is to demonstrate the features of clinical manifestations, examination, and surgical treatment of a case of spontaneous longitudinal rupture of the thyroid cartilage. PRESENTATION OF CASE: A 54-year-old male patient presented with chief complaints of pain in the front surface of the neck, difficulty swallowing and breathing during physical exertion, hyperemia of the skin on the front surface of the neck, and the presence of subcutaneous emphysema. 20 h after the onset of the symptoms, the patient reported breathing difficulties that appeared during physical exertion, and the patient walked to the hospital. Computed tomography revealed a longitudinal rupture of the thyroid cartilage, emphysema of the neck, and the presence of air in the anterior-upper mediastinum. The defect of the ruptured thyroid cartilage was treated by suturing as well as by myoplasty using sternocleidomastoid muscle. CLINICAL DISCUSSION: Our case report is in line with others, showing that patient with spontaneous rupture of the thyroid cartilage is the surgical emergency. Our approach of using myoplasty was not presented before. CONCLUSION: This case report adds evidence and knowledge about such rare disorders as spontaneous rupture the thyroid cartilage rupture. It is useful to apply the technique of myoplasty with sternocleidomastoid muscle flaps, ensuring reliable sealing of the damaged area reducing the risk of failure, and inflammatory complications, and supporting neck functions in the postoperative period.

How reliable is assessment of true vocal cord-arytenoid unit mobility in patients affected by laryngeal cancer? a multi-institutional study on 366 patients from the ARYFIX collaborative group.

PURPOSE: In clinical practice the assessment of the "vocal cord-arytenoid unit" (VCAU) mobility is crucial in the staging, prognosis, and choice of treatment of laryngeal squamous cell carcinoma (LSCC). The aim of the present study was to measure repeatability and reliability of clinical assessment of VCAU mobility and radiologic analysis of posterior laryngeal extension. METHODS: In this multi-institutional retrospective study, patients with LSCC-induced impairment of VCAU mobility who received curative treatment were included; pre-treatment endoscopy and contrast-enhanced imaging were collected and evaluated by raters. According to their evaluations, concordance, number of assigned categories, and inter- and intra-rater agreement were calculated. RESULTS: Twenty-two otorhinolaryngologists evaluated 366 videolaryngoscopies (total evaluations: 2170) and 6 radiologists evaluated 237 imaging studies (total evaluations: 477). The concordance of clinical rating was excellent in only 22.7% of cases. Overall, inter- and intra-rater agreement was weak. Supraglottic cancers and transoral endoscopy were associated with the lowest inter-observer reliability values. Radiologic inter-rater agreement was low and did not vary with imaging technique. Intra-rater reliability of radiologic evaluation was optimal. CONCLUSIONS: The current methods to assess VCAU mobility and posterior extension of LSCC are flawed by weak inter-observer agreement and reliability. Radiologic evaluation was characterized by very high intra-rater agreement, but weak inter-observer reliability. The relevance of VCAU mobility assessment in laryngeal oncology should be re-weighted. Patients affected by LSCC requiring imaging should be referred to dedicated radiologists with experience in head and neck oncology.

Spindle cell carcinomaof the larynx: A case report and literature review.

Introduction: Spindle cell carcinoma (SCC), also called sarcomatoid carcinoma or carcinosarcoma, represents a rare variant of squamous cell carcinoma that may involve multiple organs, including the larynx. It is a mixed tumor, composed of both malignant epithelial and mesenchymal elements. As the larynx appears to be an unusual site, we report a case of treated SCC laryngeal as well as a literature review of such tumor. Observation: A 72-year-old male, with 2 months' history of a progressive worsening dysphonia, was examined. The patient examination showed no cervical adenopathy, while direct laryngoscopy detected a voluminous budding formation of the anterior commissure. A biopsy was performed, in which an undifferentiated carcinoma was identified. The computed tomography (CT) confirmed the existence of a glottic tumor, which completely obstructs the lumen of the larynx. No metastasis were noticed elsewhere on the PET-CT. The tumor was then classified as T3 N0 M0. The patient underwent a total laryngectomy, thyroidectomy and neck dissection. The definitive histopathological analysis confirmed the diagnosis of SCC of the larynx with negative surgical margins. Afterward, the patient underwent adjuvant radiotherapy (RT) on the tumor bed. Conclusion: Primary laryngeal SCC is a very rare malignancy with a tendency to occur with controlateral lymph node metastasis at an early stage of the disease. Combining surgery and postoperative RT is recommended due to its aggressive profile.

Impact of radiation dose distribution on nutritional supplementation needs in head and neck cancer radiotherapy: a voxel-based machine learning approach.

Objectives: To investigate the relationship between nutritional supplementation and radiation dose to the pharyngeal constrictor muscles and larynx for head and neck (HN) cancer patients undergoing radiotherapy. Methods: We retrospectively analyzed radiotherapy (RT) dose for 231 HN cancer patients, focusing on the pharyngeal constrictors and larynx. We defined nutritional supplementation as feeding tube utilization or >10% weight loss from baseline within 90 days after radiotherapy completion. Using deformable image registration (DIR), we mapped each patient's anatomical structures to a reference coordinate system, and corresponding deformations were applied to dose matrices. Voxel doses were utilized as features for ridge logistic regression models, optimized through 5-fold cross-validation. Model performance was assessed with area under the curve of a receiver operating curve (AUC) and F1 score. We built and compared models using 1) pharyngeal constrictor voxels, 2) larynx voxels, 3) clinical factors and mean regional dose metrics, and 4) clinical factors and dose-volume histogram metrics. Test set AUCs were compared among the models, and feature importance was evaluated. Results: DIR of the pharyngeal constrictors and larynx yielded mean Dice coefficients of 0.80 and 0.84, respectively. Pharyngeal constrictors voxels and larynx voxel models had AUC of 0.88 and 0.82, respectively. Voxel-based dose modeling identified the superior to middle regions of the pharyngeal constrictors and the superior region of larynx as most predictive of feeding tube use/weight loss. Univariate analysis found treatment setting, treatment laterality, chemotherapy, baseline dysphagia, weight, and socioeconomic status predictive of outcome. An aggregated model using mean doses of pharyngeal constrictors and larynx subregions had an AUC of 0.87 and the model using conventional DVH metrics had an AUC of 0.85 with p-value of 0.04. Feature importance calculations from the regional dose model indicated that mean doses to the superior-middle pharyngeal constrictor muscles followed by mean dose to the superior larynx were most predictive of nutritional supplementation. Conclusions: Machine learning modeling of voxel-level doses enables identification of subregions within organs that correlate with toxicity. For HN radiotherapy, doses to the superior-middle pharyngeal constrictors are most predictive of feeding tube use/weight loss followed by the doses to superior portion of the larynx.

Comparison of diffusion ranges at different local anesthetic volumes during superior laryngeal nerve block.

OBJECTIVES: Ultrasound-guided superior laryngeal nerve (SLN) block is a practical and painless approach to avoid the hemodynamic stress response during endotracheal intubation and relieve sore throat after laryngeal surgery. The main purpose of this study was to establish an optimal dosage of local anesthetic when performing SLN block to help anesthetists balance analgesia and side effects. METHODS: Twenty fresh larynx specimens were obtained immediately after resection and then injected with 2-, 3-, 4-, or 5- mL of a lidocaine-blue dye mixture at bilateral SLN puncture sites. Superficial areas of deposited blue dye were measured. Dye leakage and surrounding dyed tissue were recorded. Another 40 patients were included in the ultrasound investigation. Distances between the internal branch of the SLN (iSLN) and adjacent structures were calculated. RESULTS: The dye spread area was greater with the administration of larger doses, especially to the visceral space. A 2- or 3-mL injection of local anesthetic was sufficient to infiltrate the SLN gap. A higher incidence of dye leaking out of the thyrohyoid membrane and anterior epiglottis space was observed; furthermore, there was substantially more dyed hyoid/thyroid cartilage with 4 and 5 mL of injected dye mixture than 2 mL. There was no significant difference between the specimen and ultrasound measurements of for length of iSLN-adjacent structures. CONCLUSIONS: In the Chinese population, 2- or 3- mL of local anesthetic is a safe dose during SLN block. A larger volume could overflow from the cavity to cause complications. The thyrohyoid membrane combined with the superior laryngeal artery is a reliable target for positioning the iSLN during ultrasound-guided regional anesthesia.

Netrin-1 as A neural guidance protein in development and reinnervation of the larynx.

Neural guidance proteins participate in motor neuron migration, axonal projection, and muscle fiber innervation during development. One of the guidance proteins that participates in axonal pathfinding is Netrin-1. Despite the well-known role of Netrin-1 in embryogenesis of central nervous tissue, it is still unclear how the expression of this guidance protein contributes to primary innervation of the periphery, as well as reinnervation. This is especially true in the larynx where Netrin-1 is upregulated within the intrinsic laryngeal muscles after nerve injury and where blocking of Netrin-1 alters the pattern of reinnervation of the intrinsic laryngeal muscles. Despite this consistent finding, it is unknown how Netrin-1 expression contributes to guidance of the axons towards the larynx. Improved knowledge of Netrin-1's role in nerve regeneration and reinnervation post-injury in comparison to its role in primary innervation during embryological development, may provide insights in the search for therapeutics to treat nerve injury. This paper reviews the known functions of Netrin-1 during the formation of the central nervous system and during cranial nerve primary innervation. It also describes the role of Netrin-1 in the formation of the larynx and during recurrent laryngeal reinnervation following nerve injury in the adult.