No previous study has published magnetic resonance imaging (MRI) findings for a subglottic pleomorphic adenoma. Here, we describe the case of a 62-year-old man with a subglottic pleomorphic adenoma. Endoscopic findings revealed a smooth-surfaced tumor arising from the subglottic posterior wall. MRI revealed the lesion as an isointense region on T1-weighted images, which was homogeneously enhanced. This lesion showed a heterogeneously hyperintense region on T2-weighted images. Diffusion-weighted imaging (DWI) showed slightly high intensity in the same area, with a normal or only slightly high apparent diffusion coefficient (ADC). Laryngomicrosurgery was performed for transoral excision of the subglottic tumor, resulting in a postsurgical diagnosis of pleomorphic adenoma.

BACKGROUND: No studies have been conducted to define the lengths of the upper airway\'s different segments in normal healthy adults.
OBJECTIVE: This study aimed to determine the length of the subglottis and extrathoracic trachea and the factors affecting it.
METHODS: This was an observational retrospective review study. Included 102 adult patients who underwent CT scan during the quiet inspiration phase of the upper airway.
RESULTS: The results revealed significant positive linear relationships between height and both anterior and posterior subglottic measurements (p < 0.001). Additionally, a statistically significant, moderately strong negative correlation between age and extrathoracic tracheal measurements (p > 0.001) was observed. Men exhibited longer anterior (p < 0.001) and posterior (p > 0.001) subglottic measurements. In both sexes, the average length of the anterior subglottis was 14.16 (standard deviation [SD]: 2.72) mm, posterior subglottis was 14.51 (SD: 2.85) mm and extrathoracic trachea was 66.37 (SD: 13.71) mm.
CONCLUSIONS: We concluded that a normal healthy adult\'s anterior subglottis length is 6.3-19.3 mm (mean: 14.16 [SD: 2.72] mm), posterior subglottis length is 6.1-20.0 mm (mean: 14.51 [SD: 2.85] mm) and extrathoracic trachea length is 25.2-98.5 mm (mean: 66.37 [SD: 13.71] mm). Age, height and sex affected the upper airway length.

OBJECTIVE: Recent immunologic study of the adaptive immune repertoire in the subglottic airway demonstrated high-frequency T cell clones that do not overlap between individuals. However, the anatomic distribution and antigenic target of the T cell repertoire in the proximal airway mucosa remain unresolved.
METHODS: Single-cell RNA sequencing of matched scar and unaffected mucosa from idiopathic subglottic stenosis patients (iSGS, n = 32) was performed and compared with airway mucosa from healthy controls (n = 10). T cell receptor (TCR) sequences were interrogated via similarity network analysis to explore antigenic targets using the published algorithm: Grouping of Lymphocyte Interactions by Paratope Hotspots (GLIPH2).
RESULTS: The mucosal T cell repertoire in healthy control airways consisted of highly expressed T cell clones conserved across anatomic subsites (trachea, bronchi, bronchioles, and lung). In iSGS, high-frequency clones were equally represented in both scar and adjacent non-scar tissue. Significant differences in repertoire structure between iSGS scar and unaffected mucosa was observed, driven by unique low-frequency clones. GLIPH2 results suggest low-frequency clones share targets between multiple iSGS patients.
CONCLUSIONS: Healthy airway mucosa has a highly conserved T cell repertoire across multiple anatomic subsites. Similarly, iSGS patients have highly expressed T cell clones present in both scar and unaffected mucosa. iSGS airway scar possesses an abundance of less highly expanded clones with predicted antigen targets shared between patients. Interrogation of these shared motifs suggests abundant adaptive immunity to viral targets in iSGS airway scar. These results provide insight into disease pathogenesis and illuminate new treatment strategies in iSGS.
METHODS: NA Laryngoscope, 134:3245-3252, 2024.

Safe and effective management of the neonatal airway requires knowledge, teamwork, preparation and experience. At baseline, the neonatal airway can present significant challenges to experienced neonatologists and paediatric anaesthesiologists, and increased difficulty can be due to anatomical abnormalities, physiological instability or increased situational stress. Neonatal airway obstruction is under recognised, and should be considered an emergency until the diagnosis and physiological implications are understood. When multiple types of difficulties are present or there are multiple levels of anatomical obstruction, the challenge increases exponentially. In these situations, preparation, multi-disciplinary teamwork and a consistent hospital-wide approach will help to reduce errors and morbidity.

OBJECTIVE: Recent translational scientific efforts in subglottic stenosis (SGS) support a disease model where epithelial alterations facilitate microbiome displacement, dysregulated immune activation, and localized fibrosis. Given the observed immune cell infiltrate in SGS, we sought to test the hypothesis that SGS cases possessed a low diversity (highly clonal) adaptive immune response when compared with healthy controls.
METHODS: Single cell RNA sequencing (scRNA-seq) of subglottic mucosal scar in iSGS (n = 24), iLTS (n = 8), and healthy controls (n = 7) was performed. T cell receptor (TCR) sequences were extracted, analyzed, and used to construct repertoire structure, compare diversity, interrogate overlap, and define antigenic targets using the Immunarch bioinformatics pipeline.
RESULTS: The proximal airway mucosa in health and disease are equally diverse via Hill framework quantitation (iSGS vs. iLTS vs. Control, p > 0.05). Repertoires do not significantly overlap between individuals (Morisita <0.02). Among iSGS patients, clonality of the TCR repertoire is driven by CD8+ T cells, and iSGS patients possess numerous TCRs targeting viral and intercellular pathogens. High frequency clonotypes do not map to known targets in public datasets.
CONCLUSIONS: SGS cases do not possess a lower diversity adaptive immune infiltrate when compared with healthy controls. Interestingly, the TCR repertoire in both health and disease contains a restricted number of high frequency clonotypes that do not significantly overlap between individuals. The target of the high frequency clonotypes in health and disease remain unresolved.
METHODS: NA Laryngoscope, 134:1757-1764, 2024.

An 8-year-old child was admitted to our ENT department for a year because of a hoarse voice. An endoscopic examination displayed that a cystic, solid lesion can be seen in the right subglottis. The lesion was removed using a CO2 laser under general anesthesia. Postoperative histopathology confirmed granular cell tumor (GCT), S-100(+), vimentin (+), and SOX-10(+). GCT, also known as the Abrikossoff tumor, is a rare benign tumor that rarely occurs in the larynx, particularly in children. This case report emphasizes that considerable attention should be given to the differential diagnosis of the laryngeal granulosa cell tumor. Given the recurrence risk of GCT, long-term postoperative follow-up is necessary.

OBJECTIVE: Determine the ideal head position to optimize visualization of the subglottis using flexible laryngoscopy.
METHODS: Prospective cohort study.
METHODS: Outpatient multidisciplinary airway clinic at a tertiary care center.
METHODS: Patients presenting to a multidisciplinary airway clinic undergoing nasoendoscopic airway examination were enrolled. Three head positions were utilized to examine the subglottis during laryngoscopy: \"sniffing,\" chin tuck, and stooping positions. In-office reviewers and blinded clinician participants evaluated views of the airway based on Cormack-Lehane (CL) scale, airway grade (AG), and visual analog scale (VAS). Demographic data were obtained. Statistical analysis compared head positions and demographic data using Student\'s t test, analysis of variance, and Tukey\'s post hoc analysis.
RESULTS: One hundred patients participated. No statistical differences existed among in-clinic or blinded reviewers for the CL score in any head position (p = .35, .5, respectively). For both AG and VAS, flexed and stooping positions were rated higher than the sniffing positions by both in-clinic and blinded reviewers (p < .01 for all analyses), but there was no statistical difference between these two positions (p = .28, .18, respectively). There was an inverse correlation between age and scores for AG and VAS in the flexed position for both sets of reviewers (p = .02, <.01 respectively), and a higher body mass index was significantly associated with the need to perform tracheoscopy for full airway evaluation (p < .01).
CONCLUSIONS: Both flexion and stoop postures can be implemented by an experienced endoscopist in awake, transnasal flexible laryngoscopy to enhance visualization of the subglottic airway.

Subglottic hemangiomas are rare in adulthood. The presence of the lesion in the subglottic region makes it even more unusual. Moreover, these lesions do not have a typical course and involution changes as seen in the infantile forms. An elderly female initially came with a brief history of dyspnea and symptoms of upper respiratory tract infection. The patient also complained of a change of voice and noisy breathing, with a recent history of intubation following COVID-19 pneumonia and late-onset bronchial asthma. Flexible nasopharyngolaryngoscopy showed a mass below the vocal folds, which was seen to arise from the posterior subglottic region. The patient eventually underwent endoscopic excision of the lesion under general anesthesia and recovered well. Symptoms of hoarseness and stridor, along with a history of intubation, should raise a high index of suspicion for laryngeal diseases. A delay in the diagnosis of an obstructing lesion in the subglottis occurs in the presence of a confounding lung infection and overlap of clinical features with those of bronchial asthma. Surgical excision is required not only to alleviate obstructive symptoms but also to rule out malignancy.

Juvenile Xanthogranuloma (XG) is a rare disorder that belongs to the heterogeneous group of histiocytic neoplasms, characterized by a clonal expansion of non-Langerhans cell histiocytes that share a dermal macrophage phenotype. Although the head and neck region is the most common reported site of involvement by the Juvenile Xanthogranuloma family, laryngeal localization is extremely rare. We report a unique case of Adult Onset Xanthogranuloma with subglottic localization, presenting as a solitary laryngeal mass without other systemic or cutaneous lesions. A review of the previously described cases of laryngeal Xanthogranuloma has been performed, highlighting 7 cases of Juvenile Xanthogranuloma and only 3 cases of Adult Onset Xanthogranuloma. Despite the extreme rarity of laryngeal localization of XG, this histiocytic neoplasm should be considered as a differential diagnosis for laryngeal masses causing airway obstruction, even in the absence of other concomitant manifestations.

The larynx serves as the gateway between the upper and lower respiratory tracts and is involved in the tasks of phonation, deglutition, and airway protection. Familiarity with the complex anatomy of the larynx is critical for detecting and characterizing disease in the region, especially in cancer staging. In this article, we review the anatomy of the larynx and cervical trachea, including an overview of their cartilages, supporting tissues, muscles, mucosal spaces, neurovascular supply, and lymphatics, followed by correlation to the clinically relevant anatomic sites of the larynx. Imaging techniques for evaluating the larynx and trachea will also be discussed briefly.