Laryngeal Response Research Articles

Uncovering the neural control of laryngeal activity and subglottic pressure in anaesthetized rats: insights from mesencephalic regions

To assess the possible interactions between the dorsolateral periaqueductal gray matter (dlPAG) and the different domains of the nucleus ambiguus (nA), we have examined the pattern of double-staining c-Fos/FoxP2 protein immunoreactivity (c-Fos-ir/FoxP2-ir) and tyrosine hydroxylase (TH) throughout the rostrocaudal extent of nA in spontaneously breathing anaesthetised male Sprague–Dawley rats during dlPAG electrical stimulation. Activation of the dlPAG elicited a selective increase in c-Fos-ir with an ipsilateral predominance in the somatas of the loose (p < 0.05) and compact formation (p < 0.01) within the nA and confirmed the expression of FoxP2 bilaterally in all the domains within the nA. A second group of experiments was made to examine the importance of the dlPAG in modulating the laryngeal response evoked after electrical or chemical (glutamate) dlPAG stimulations. Both electrical and chemical stimulations evoked a significant decrease in laryngeal resistance (subglottal pressure) (p < 0.001) accompanied with an increase in respiratory rate together with a pressor and tachycardic response. The results of our study contribute to new data on the role of the mesencephalic neuronal circuits in the control mechanisms of subglottic pressure and laryngeal activity.

Laryngeal Recalibration Therapy Improves Laryngopharyngeal Symptoms in Patients With Suspected Laryngopharyngeal Reflux Disease.

Laryngopharyngeal symptoms such as cough, throat clearing, voice change, paradoxic vocal fold movement, or laryngospasm are hyper-responsive behaviors resulting from local irritation (e.g., refluxate) and heightened sympathetic tone. Laryngeal recalibration therapy (LRT) guided by a speech-language pathologist (SLP) provides mechanical desensitization and cognitive recalibration to suppress hyper-responsive laryngeal patterns. The aim of this study was to assess symptom response to LRT among patients with chronic laryngopharyngeal symptoms undergoing evaluation of gastroesophageal reflux disease (GERD). Adults with chronic laryngopharyngeal symptoms referred for evaluation of GERD to a single center were prospectively followed. Inclusion criteria included ≥2 SLP-directed LRT sessions. Data from endoscopy, ambulatory reflux monitoring, and patient-reported outcomes were collected when available. The primary outcome was symptom response. Sixty-five participants completed LRT: mean age 55.4 years (SD 17.2), 46 (71%) female, mean body mass index 25.6 kg/m 2 (6.8), and mean of 3.7 (1.9) LRT sessions. Overall, 55 participants (85%) met criteria for symptom response. Specifically, symptom response was similar between those with isolated laryngopharyngeal symptoms (13/15, 87%) and concomitant laryngopharyngeal/esophageal symptoms (42/50, 84%). Among participants who underwent reflux monitoring, symptom response was similar between those with proven, inconclusive for, and no GERD (18/21 [86%], 8/9 [89%], 10/13 [77%]). Eighty-five percent of patients with chronic laryngopharyngeal symptoms referred for GERD evaluation who underwent LRT-experienced laryngeal symptom response. Rates of symptom response were maintained across patients with or without proven GERD and patients with or without concomitant esophageal reflux symptoms. SLP-directed LRT is an effective approach to incorporate into multidisciplinary management of chronic laryngopharyngeal symptoms/laryngopharyngeal reflux disease.

Laryngeal response to high-intensity exercise in healthy athletes

IntroductionExercise-induced laryngeal obstruction (EILO) is a common cause of exertional breathing problems. The current diagnostic approach rests on evaluation of laryngeal obstruction visualised by laryngoscopy performed continuously throughout a maximal...

Efficacy of intratracheal dexmedetomidine on recovery from general anaesthesia in paediatric patients undergoing lower abdominal surgeries: A randomised controlled trial.

This study investigated the effectiveness of intratracheal dexmedetomidine in reducing untoward laryngeal responses in paediatrics undergoing lower abdominal surgeries. This trial included 60 patients divided into two groups scheduled for lower abdominal surgeries. Group D were given intratracheal dexmedetomidine at a dosage of 0.5mg/kg, while Group C received intratracheal saline (0.9%). The cough severity score, the Paediatric Objective Pain Scale for pain assessment, awareness, extubation, emergence agitation score, Ramsay sedation score and adverse effects were recorded. There was a significant difference in the incidence of coughing severity between Groups D and C both at extubation and after five minutes of extubation (p < 0.001). The median scores of the Paediatric Objective Pain Scales and the median agitation scales of Group D were significantly lower over the first four hours (p < 0.050). The mean time to first request rescue analgesia was significantly longer in the D group than in the control group (p < 0.001). The mean total consumption of rescue analgesia in the first 24 hours postoperatively was significantly lower in the dexmedetomidine group (p < 0.050). Awareness and extubation times were comparable in both groups, and none of the subjects reported any adverse effects. In the current study, lower abdominal surgery patients who received intratracheal dexmedetomidine at a dose of 0.5mg/kg 30 minutes before the completion of the procedure experienced smooth extubation and balanced anaesthetic recovery.

Pilot observational cohort study to determine whether waveform and flow traces from mechanical insufflation–exsufflation (MI-E) can be used to identify laryngeal responses to MI-E and thus optimise treatment algorithms in neuromuscular patients in a tertiary centre: a protocol description

IntroductionPatients with neuromuscular disease often have a weak and ineffective cough due to respiratory muscle weakness. One treatment option is mechanical insufflation–exsufflation (MI-E), also known as cough assist, which is...

Intraoperative cortical stimulation mapping with laryngeal electromyography for the localization of human laryngeal motor cortex.

The objectives of this study were to describe the authors' clinical methodology and outcomes for mapping the laryngeal motor cortex (LMC) and define localization of the LMC in a cohort of neurosurgical patients undergoing intraoperative brain mapping. Because of mapping variability across patients, the authors aimed to define the probabilistic distribution of cortical sites that evoke laryngeal movement, as well as adjacent cortical somatotopic representations for the face (mouth), tongue, and hand. Thirty-six patients underwent left (n = 18) or right (n = 18) craniotomy with asleep motor mapping. For each patient, electromyography (EMG) electrodes were placed in the face, tongue, and hand; a nerve integrity monitor (NIM) endotracheal tube with surface electrodes detected EMG activity from the bilateral vocal folds. After dense cortical stimulation was delivered throughout the sensorimotor cortex, motor responses were then mapped onto a three-dimensional reconstruction of the patient's cortical surfaces for location characterization of the evoked responses. Finally, stimulation sites were transformed into a two-dimensional coordinate system for probabilistic mapping of the stimulation site relative to the central sulcus and sylvian fissure. The authors found that the LMC was predominantly localized to a mid precentral gyrus region, dorsal to face representation and surrounding a transverse sulcus ventral to the hand knob. In 14 of 36 patients, the authors identified additional laryngeal responses located ventral to all orofacial representations, providing evidence for dual LMC representations. The authors determined the probabilistic distribution of the LMC. Cortical stimulation mapping with an NIM endotracheal tube is an easy and effective method for mapping the LMC and is simply integrated into the current neuromonitoring methods for brain mapping.

Modulation of the swallowing reflex by stimulation of the gigantocellular reticular nucleus in the rat

ObjectivesThe gigantocellular reticular nucleus (Gi) projects to the nuclues of the solitary tract nucleus (NTS) and the lateral reticular formation (LRF) above the nucleus ambiguus. The swallowing central pattern generator comprises the NTS and the LRF. The present study examined whether stimulation of the Gi affects the swallowing reflex. MethodsExperiments were performed on urethane-anesthetized rats. The swallowing reflex was evoked by repetitive electrical stimulation of the superior laryngeal nerve and responses were recorded from the mylohyoid muscle on an electromyogram. The Gi was stimulated electrically. In addition, glutamate was injected into the Gi. The Friedman's test, followed by the Wilcoxon signed-rank test with Bonferroni correction, were used to assess the effects of electrical stimulation of the Gi. The Wilcoxon signed-rank test was used to assess the effects of glutamate injection into the Gi. Differences were considered significant at the P < 0.05 level. ResultsThe number of swallows was significantly increased or decreased by electrical stimulation of the Gi or after injection of glutamate into the Gi. In both electrical stimulation of the Gi and injection of glutamate into the Gi, the onset latency of the first swallow was prolonged when the number of swallows was decreased but showed no change when the number of swallows was increased. ConclusionsThe present results suggest that the Gi is involved in the control of swallowing.

Letter from Norway

Letter from Norway

Effect of intravenous fentanyl on cough reflex and quality of endotracheal intubation in cats

ObjectiveTo assess the effects of intravenous (IV) fentanyl on cough reflex and quality of endotracheal intubation (ETI) in cats. Study designRandomized, blinded, negative controlled clinical trial. AnimalsA total of 30 client-owned cats undergoing general anaesthesia for diagnostic or surgical procedures. MethodsCats were sedated with dexmedetomidine (2 μg kg–1 IV), and 5 minutes later either fentanyl (3 μg kg–1, group F) or saline (group C) was administered IV. After alfaxalone (1.5 mg kg–1 IV) administration and 2% lidocaine application to the larynx, ETI was attempted. If unsuccessful, alfaxalone (1 mg kg–1 IV) was administered and ETI re-attempted. This process was repeated until successful ETI. Sedation scores, total number of ETI attempts, cough reflex, laryngeal response and quality of ETI were scored. Postinduction apnoea was recorded. Heart rate (HR) was continuously recorded and oscillometric arterial blood pressure (ABP) was measured every minute. Changes (Δ) in HR and ABP between pre-intubation and intubation were calculated. Groups were compared using univariate analysis. Statistical significance was set as p < 0.05. ResultsThe median and 95% confidence interval of alfaxalone dose was 1.5 (1.5–1.5) and 2.5 (1.5–2.5) mg kg–1 in groups F and C, respectively (p = 0.001). The cough reflex was 2.10 (1.10–4.41) times more likely to occur in group C. The overall quality of ETI was superior in group F (p = 0.001), with lower laryngeal response to ETI (p < 0.0001) and ETI attempts (p = 0.045). No differences in HR, ABP and postinduction apnoea were found. Conclusions and clinical relevanceIn cats sedated with dexmedetomidine, fentanyl could be considered to reduce the alfaxalone induction dose, cough reflex and laryngeal response to ETI and to improve the overall quality of ETI.

Standardized Behavioral Treatment Improves Chronic Cough

ObjectivesNeurogenic Laryngeal Hypersensitivity (NLH) refers to a constellation of upper airway symptoms thought to be caused by a disturbance in afferent and/or efferent neural pathways creating an exaggerated hypersensitive laryngeal response. There is evidence to support behavioral therapy as treatment for improving symptoms from laryngeal motor dysfunction to sensory disturbance. This study aims to determine if there is significant symptomatic improvement in patients with NLH who received non-pharmacologic behavioral treatment performed by trained SLPs. Study designA retrospective review. MethodsA review of all patients with NLH from 2017 to 2020 was performed at a tertiary care voice and swallowing center. Subjects with persistent symptoms despite maximal medical management were considered for inclusion. Newcastle Laryngeal Hypersensitivity Questionnaire (NLHQ) was completed by patients before and after undergoing therapy by one of three trained SLPs. Posttherapy improvement was determined by utilizing the NLHQ's minimal clinically important difference of 1.7 points. ResultsA total of 81 patients were included in this study. Study participants included 61 women and 20 men with an average age of 60.64±14.05 years. There was a statistically significant difference between the pre and post therapy scores amongst all patients when treated by each individual SLP and all three SLPs combined (P < 0.008). There was a clinically significant change in 66% of all patients, 76% of which presented with abnormal NLHQ scores, and 14% who presented with normal NLHQ scores. ConclusionsA standardized behavioral treatment protocol for patients with symptoms consistent with NLH is effective in improving symptoms in a large majority of patients. When following a standardized protocol SLPs can obtain similar results for their patients.

2022 Year in Review: Mechanical Insufflation-Exsufflation

Manual and mechanical cough augmentation techniques are used for airway clearance when cough effort is ineffective. Mechanical insufflation-exsufflation (MI-E) has been a mainstay for respiratory complications of neuromuscular disorders, but its use has expanded to other conditions that result in respiratory muscle weakness and impaired cough, such as intubation and mechanical ventilation. Mechanical in-exsufflation has been used for cough augmentation in both adults and children but has been more widely evaluated in adults. Optimal settings for pressure and time are unknown. Newer MI-E devices have the option for oscillatory vibrations during therapy to facilitate secretion clearance. However, use of oscillations is not supported by the available evidence. Pressure settings and the interface used to administer MI-E influence peak expiratory flow generated during therapy. Laryngeal dysfunction can impact successful MI-E treatment in individuals with neuromuscular disorders and bulbar involvement. Transnasal fiberoptic laryngoscopy and videofluoroscopy may be helpful in assessing the laryngeal response and in customizing pressure settings to decrease the incidence of upper airway collapse during therapy. Electrical impedance tomography has been used for monitoring during mechanical ventilation and may have a role in assessing the effectiveness of MI-E. Much of the literature that supports MI-E is derived from small, single-center studies of adult populations. Future study is warranted for efficacy and optimization of MI-E therapy in various clinical applications.

Is it feasible to perform a continuous laryngoscopy exercise test with a cold air inhalate? A case report.

The continuous laryngoscopy exercise (CLE) test can be combined with breathing cold air. Combining the CLE test and cold air does not cause excessive discomfort. The indicated laryngeal responses with cold air support the need for more research. https://bit.ly/3AChJ7V.

Auditory and somatosensory feedback mechanisms of laryngeal and articulatory speech motor control.

Speech production is a complex motor task involving multiple subsystems. The relationships between these subsystems need to be comprehensively investigated to understand the underlying mechanisms of speech production. The goal of this paper is to examine the differential contributions of 1) auditory and somatosensory feedback control mechanisms, and 2) laryngeal and articulatory speech production subsystems on speech motor control at an individual speaker level using altered auditory and somatosensory feedback paradigms. Twenty young adults completed speaking tasks in which sudden and unpredictable auditory and physical perturbations were applied to the laryngeal and articulatory speech production subsystems. Auditory perturbations were applied to laryngeal or articulatory acoustic features of speech. Physical perturbations were applied to the larynx and the jaw. Pearson-product moment correlation coefficients were calculated between 1) auditory and somatosensory reflexive responses to investigate relationships between auditory and somatosensory feedback control mechanisms, and 2) laryngeal and articulatory reflexive responses as well as acuity measures to investigate the relationship between auditory-motor features of laryngeal and articulatory subsystems. No statistically significant correlations were found concerning the relationships between auditory and somatosensory feedback. No statistically significant correlations were found between auditory-motor features in the laryngeal and articulatory control subsystems. Results suggest that the laryngeal and articulatory speech production subsystems operate with differential auditory and somatosensory feedback control mechanisms. The outcomes suggest that current models of speech motor control should consider decoupling laryngeal and articulatory domains to better model speech motor control processes.

Significance of induction chemotherapy combined with cetuximab in laryngeal preservation rate of locally advanced hypopharyngeal cancer.

e18078 Background: Anatomical and functional laryngeal organ preservation is critical for patients with locally advanced hypopharyngeal squamous cell carcinoma (LAHSCC). Induction chemotherapy with taxanes (T), cisplatin (P) and 5-FU (F) is a therapeutical option in patients with a strong desire to preserve the throat, whether enhanced induction chemotherapy (TPF/TP combined with cetuximab) can improve laryngeal preservation rate (LPR) and objective response rate (ORR) of LAHSCC remains controversial. Here we report the results of a retrospectively study comparing TPF/TP with TPF/TP plus cetuximab. Methods: Nanfang Hospital database was retrospectively queried for LAHSCC patients who received 2 cycle induction chemotherapy with TPF/TP (paclitaxel, cisplatin, 5-Fu) with or without concurrent use of cetuximab for ORR. Results: A total of 81 patients were identified including 36 which had concurrent use of TPF/TP and cetuximab. The overall ORR was 71.60% (58/81), patients in the TPF/TP +Cetuximab group had significantly improved ORR (83.33% (30/36) vs 62.22% (28/45) (P = 0.037) compared to TPF/TP group. After IC, 24 patients underwent laryngopharyngectomies, 6 underwent larynx-preserving surgeries, 51 underwent CCRT and 3 received salvage surgeries. In addition, the total 3-month laryngeal preservation rate (LPR) was 69.13% (56/81), the cetuximab-associated LPR benefit was observed in patients with 60.0% (27/45) in the TPF/TP group, and 80.56% (29/36) in the TPF/TP +Cetuximab group (P &lt; 0.001). The adverse events of grade 3 or 4 were similar between the two groups except for skin rash (TPF/TP group 6.7% vs TPF/TP+Cetuximab 41.7%, P &lt; 0.001), which gradually subsided within 2 weeks after the drug withdrawal. Conclusions: Concurrent cetuximab use with TPF/TP induction chemotherapy in LAHSCC patients was associated with improved ORR and short-term LPR, with tolerable toxicity. Further prospective evidence from larger trials is warranted.

Investigating Past Trauma in Laryngoresponders Versus Non-Laryngoresponders: Piloting New Methods in an Exploratory Study

This exploratory pilot study aimed to probe the relationship between past experiences of trauma in people who self-identify as "laryngoresponders" compared to those who do not. It also explored the communicative context of past traumatic events in laryngoresponders versus non-laryngoresponders. Prospective, within-subjects experimental design. 29 vocally healthy cisgender women (ages 19 to 56) completed a battery of validated self-report measures relating to their past traumatic experiences. Participants also completed two original self-report measures designed to provide insight about (1) where stress tends to manifest in their body and (2) communicative settings of participants' past trauma. Six participants (21%) self-identified a predictable laryngeal and/or vocal response to acute stress and thus comprise the laryngoresponders group. Laryngoresponders exhibited worse scores on 75% of all trauma-related variables compared to non-laryngoresponders, and Emotional Neglect was disproportionately represented in laryngoresponders. Participants with a reported history of childhood Emotional Neglect (83% of laryngoresponders, 35% of nonlaryngoresponders) reported quantitatively "less ideal" communication experiences in the context of past traumatic experiences. Other investigators identify the larynx as a "vulnerable body pathway" for some women. This pilot study of adult women without voice complaints revealed several commonalities amongst self-reported laryngoresponders, and compels further exploration of the voice-trauma relationship.

Adjustments of non-invasive ventilation and mechanically assisted cough by combining ultrasound imaging of the larynx with transnasal fibre-optic laryngoscopy: a protocol for an experimental study

IntroductionApplication of non-invasive positive airway pressure may provoke laryngeal responses that obstruct the airways, especially in patients with disturbed laryngeal control. To control and adjust for this, transnasal fibre-optic laryngoscopy...

Transcutaneous Laryngeal Ultrasonography for Assessing Vocal Cord Twitch Response in Thyroid Operation during Predissection Vagus Nerve Stimulation.

BACKGROUNDIn this study, we aimed to report our experience with the use of intraoperative transcutaneous laryngeal ultrasonography (TLUSG) to evaluate the vocal cord twitch response during predissection vagus nerve stimulation in thyroid surgeries and examine the reliability of this technique when compared with that of laryngeal twitch palpation (LTP).STUDY DESIGNThe prospective data collection of consecutive patients who underwent open thyroidectomy with intraoperative neuromonitoring (IONM) was reviewed retrospectively. We recorded the electromyographic activity and assessed the vocal cord twitch response on LTP, TLUSG. We compared the accessibility, sensitivity, and specificity of the techniques.RESULTSA total of 110 patients (38 men and 72 women) with 134 nerves at risk were enrolled. The vocal cord was assessable by TLUSG in 103 (93.6%) patients and by LTP in 64 (59.1%) patients. Two patients showed negative predissection IONM signal but positive on TLUSG and the presence of laryngeal twitch response confirmed by laryngoscopy. Fourteen patients showed positive IONM signals and presence of the vocal cord twitch response on TLUSG but not on LTP. The sensitivity and specificity were 70.21% and 100%, respectively, for LTP, and those both were 100% for TLUSG. For patients who could be assessed using both techniques, TLUSG had better accuracy than LTP (100% vs 80.33%, p = 0.0005).CONCLUSIONSThe innovative intraoperative application of TLUSG is better for evaluating the laryngeal twitch response than LTP. This technique provides practical troubleshooting guidance for patients with no IONM signals during predissection vagus nerve stimulation.

Laryngeal hypersensitivity and abnormal cough response during mannitol bronchoprovocation challenge.

Inhalational challenge with dry mannitol powder may potentially induce cough by two mechanisms: airway bronchoconstriction or laryngeal irritation. This prospective observational study investigated laryngeal and bronchial components of cough induced by mannitol challenge. We recruited consecutive patients referred for clinical mannitol challenge. The Newcastle Laryngeal Hypersensitivity Questionnaire (LHQ) was administered. Throughout testing, coughs were audio-recorded to derive a cough frequency index per time and dose of mannitol. Relationships between cough indices, laryngeal hypersensitivity and bronchial hyperresponsiveness (BHR) were examined. Participants were classified by cough characteristics with k-means cluster analysis. Of 90 patients who underwent challenge, 83 completed both the questionnaire and challenge. Cough frequency was greater in patients with abnormal laryngeal hypersensitivity (p=0.042), but not in those with BHR. There was a moderate negative correlation between coughs per minute and laryngeal hypersensitivity score (r=-0.315, p=0.004), with lower LHQ scores being abnormal. Cluster analysis identified an older, female-predominant cluster with higher cough frequency and laryngeal hypersensitivity, and a younger, gender-balanced cluster with lower cough frequency and normal laryngeal sensitivity. Cough frequency during mannitol challenge in our cohort reflected laryngeal hypersensitivity rather than BHR. Laryngeal hypersensitivity was more often present among older female patients. With the incorporation of cough indices, mannitol challenge may be useful to test for laryngeal hypersensitivity as well as BHR.

Applicability of Selective Electrical Surface Stimulation in Unilateral Vocal Fold Paralysis.

ObjectiveSelective electrical surface stimulation (SES) of the larynx is not yet routinely considered therapy option in treatment of unilateral vocal fold paralysis (UVFP). Goal of this monocentric feasibility study was to provide systematic data on applicability of SES of intrinsic laryngeal muscles in UVFP under consideration of sensitivity and discomfort thresholds and nonselective side effects.MethodsThirty‐two UVFP patients were included in the study. Symmetric triangular‐shape, charge‐balanced pulse widths (PWs) of 1, 10, 25, 50, 100, 250, and 500 milliseconds (ms) were tested with increasing amplitudes (AMPs). The stimulation was delivered as a train of five pulses using square surface electrodes. Selective laryngeal responses were examined by flexible laryngoscopy. Nonselective side effects (swallowing reflex, coughing, different severity degrees of unspecific strap muscle/platysma response) were judged by observation.ResultsSelective laryngeal response could be triggered in 28/32 (87.5%) patients during respiration/rest and in 26/32 (81.3%) patients during phonation. The most effective PWs for the selective eliciting of selective bilateral vocal fold adduction are comprised between 50 and 100 ms in combination with an average AMP comprised between 7.1 and 7.2 mA.ConclusionOur results indicate that, in UVFP patients, PWs comprised between 50 and 100 ms in combination with a median AMP between 7.1 and 7.2 mA are expected to deliver in >75% of the cases a specific, effective, and safe bilateral adduction of the VF.Level of Evidence3 Laryngoscope, 131:E2566–E2572, 2021

Short-term whole body cigarette smoke exposure induces regional differences in cellular response in the mouse larynx.

The larynx is an essential organ in the respiratory tract and necessary for airway protection, respiration, and phonation. Cigarette smoking is a significant risk factor associated with benign and malignant laryngeal diseases. Despite this association, the underlying mechanisms by which cigarette smoke (CS) drives disease development are not well elucidated. In the current study, we developed a short-term murine whole body inhalation model to evaluate the first CS-induced cellular responses in the glottic [i.e. vocal fold (VF)] and subglottic regions of the larynx. Specifically, we investigated epithelial cell proliferation, cell death, surface topography, and mucus production, at various time points (1 day, 5 days, 10 days) after ∼ 2 h exposure to 3R4F cigarettes (Delivered dose: 5.6968 mg/kg per cigarette) and following cessation for 5 days after a 5 day CS exposure (CSE). CSE elevated levels of BrdU labeled proliferative cells and p63 labeled epithelial basal cells on day 1 in the VF. CSE increased proliferative cells in the subglottis at days 5, 10 and following cessation in the subglottis. Cleaved caspase-3 apoptotic activity was absent in VF at all time points and increased at day 1 in the subglottis. Evaluation of the VF surface by scanning electron microscopy (SEM) revealed significant epithelial microprojection damage at day 10 and early signs of necrosis at days 5 and 10 post-CSE. SEM visualizations additionally indicated the presence of deformed cilia at days 5 and 10 after CSE and post-cessation in the respiratory epithelium lined subglottis. In terms of mucin content, the impact of short-term CSE was observed only at day 10, with decreasing acidic mucin levels and increasing neutral mucin levels. Overall, these findings reveal regional differences in murine laryngeal cellular responses following short-term CSE and provide insight into potential mechanisms underlying CS-induced laryngeal disease development.