Measurements of pre- and postpubertal human larynx: a cadaver study

Morphometric Examination of the Larynx in Turkish Population

OBJECTIVE

The aim of this study was to measure laryngeal dimensions in a sample of Turkish cadavers, including males and females of various ages and heights.

MATERIALS AND METHODS

Morphological measurement was performed on 102 laryngeal specimens. Hyoid bone and laryngeal cartilages were removed from human cadavers. All dimensions of the cartilages were measured using a thread and vernier calipers. Age, sex, and height were recorded. All the parameters for male and female were compared. Statistical comparisons were made using Student's t test and Pearson's correlation.

RESULTS

The following measurements were significantly greater in males than in females: length of the greater horn of hyoid bone (P < 0.05) and hyoid body heights (P < 0.001), length and width of epiglottis (P < 0.001), transversal and anteroposterior diameters, and anterior and posterior height of the cricoid (P < 0.01). The dimensions of male and female thyroid cartilages differed significantly (P < 0.001). Age was not significantly correlated with any parameter tested. Height showed weakly significant positive correlations with hyoid body height, epiglottis height, lateral and anteroposterior diameters of the cricoid, posterior height of the cricoid, thyroid superior horn length, lamina breadth, and anterior height.

CONCLUSION

Mean measurements were significantly greater in males than in females. However, there were no significant correlations between age and any parameter examined. Weakly significant positive correlations were observed between height and hyoid bone and laryngeal cartilage measurements. This study is the first cadaver study to investigate epiglottis, cricoid and thyroid cartilage, and hyoid bone measurements in the Turkish adult population with such a large sample size.

Voice Disorder Prevalence and Vocal Health Characteristics in Adolescents

Importance

Voice disorders impede communication and detract from quality of life, yet little is known about how voice problems present in adolescents. This study characterized the prevalence of voice problems and vocal health characteristics of adolescents throughout the US.

Objective

To determine the prevalence of adolescent voice problems in the US as well as the symptoms, voice use patterns, and risk factors associated with these problems.

Design, Setting, and Participants

This prospectively performed, cross-sectional survey study conducted from March to June 2023 included a probability sample of adolescents (aged 13-17 years) who were located across the US.

Main Outcome and Measures

Adolescents were surveyed concerning voice use, voice symptoms, demographic information, and substance use patterns. The Vocal Fatigue Index (VFI) was also completed. Fisher exact tests, χ2 tests, and logistic regression were used to compare those with and without reported voice problems.

Results

Five-hundred and two adolescents participated (51.6% participation rate), including 248 female (49.4%), 7 nonbinary (1.3%), 254 male (50.6%), 4 transfemale (0.7%), and 3 transmale individuals (0.5%) (mean [SD] age, 15.2 [1.3] years). The lifetime prevalence of voice problems was 24.3%, and current prevalence was 7.4%. Voice-related diagnoses included dysphonia associated with acute illness, vocal hyperfunction, benign lesions, and muscle tension. The mean (SD) VFI score was 4.7 (8.09) for part 1, 1.6 (3.2) for part 2, and 2.1 (3.2) for part 3. Adolescents with voice complaints presented with significantly higher VFI scores than those without voice problems (Cohen d for part 1 = 0.78, part 2 = 0.59, and part 3 = 0.79). Voice problems interfered with daily tasks, prevented participation in extracurricular activities, limited the ability to sing, and were associated with school absences. Voice use patterns associated with voice problems included frequent loud voice use, coughing, and/or throat clearing. Risk factors for increased voice problem prevalence included part-time employment in childcare (odds ratio [OR], 6.4; 95% CI, 1.6-26.3), singing (OR, 2.08; 95% CI, 1.3-3.1), performance-related extracurricular activities (ie, musical theater [OR, 2.67; 95% CI, 1.1-6.6 ], karaoke [OR, 3.08; 95% CI, 1.3-6.9]), vaping (OR, 1.99; 95% CI, 1.1-3.5), and/or secondhand smoke exposure (OR, 1.83; 95% CI, 1.2-2.7). Adolescents identifying as transgender were more than 4 times (OR, 4.44; 95% CI, 0.63-31.2) as likely to report voice problems compared with cisgender adolescents.

Conclusions

The results of this survey study illuminate the nature of voice problems in adolescents and may guide clinicians in preventing and treating voice disorders in this population. Future work may define the mechanisms through which these factors are associated with the risk for voice disorders in adolescents and determine whether observed relationships are causal or associative.

Gender-Affirming Facial Surgery: Lower Third of the Face

This article is intended to give the reader an overview of facial gender-affirming procedures applicable to the lower face and neck. A review of facial analysis in the context of masculine versus feminine facial features and the contributions of both soft tissue and bone to this anatomy is provided. The use of systematic facial evaluation and patient-driven concerns as a guide for presurgical planning is reviewed. Detailed descriptions of the unique surgical interventions to feminize the soft tissues and the skeletal framework of the lower face and neck are provided.

Laryngeal Framework Surgical Anatomy: A Radiological Study

PURPOSE

Awareness of variations in laryngeal anatomy among different age and gender groups is crucial during laryngeal framework surgery. The aim of this study is to demonstrate the relationship between gender and laryngeal radiologic morphometrics among different age groups and the applicability of important anatomical landmarks of laryngeal surgery.

METHODS

Laryngeal images of 180 adult patients older than 18 years of age were obtained by computed tomography and assessed. A total of 11 measurements of important laryngeal landmarks were taken from the patients' computed tomography images. Results were subgrouped according to gender and age, and these groups were compared for each measurement.

RESULTS

The majority of laryngeal measurements obtained in the study were higher in males than females, with the exception of the interlaminar angle. The mean interlaminar angle value was 88.27°± 14.99 for males and 103.04°± 14.81 for females (P <0.005). The distance from the anterior commissure to the inferior border of the thyroid cartilage was 10.46 ± 2.5 mm for males and 7.72 ± 1.9 mm for females. The anterior commissure locates slightly higher than the midpoint of the distance from the thyroid notch to the thyroid inferior border. The shortest distance between the muscular process of the arytenoid cartilage and the thyroid cartilage was found to be 9.60 ± 3.47 mm for males and 7.72 ± 2.33 mm for females (P <0.001).

CONCLUSION

Observation of obvious diversities in the size and distance of the important laryngeal structures between the gender groups is an important factor to be considered for successful laryngeal framework surgery. Also, using the midpoint of the thyroid cartilage as a landmark for anterior commissure is a practical method during surgery, especially for thyroplasty.

A longitudinal follow-up of continuous laryngoscopy during exercise test scores in athletes irrespective of laryngeal obstruction, respiratory symptoms, and intervention

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) is diagnosed by the continuous laryngoscopy during exercise (CLE) test. Whether or how much CLE test scores vary over time is unknown. This study aimed to compare CLE test scores in athletes over time, irrespective of respiratory symptoms and grade of laryngeal obstruction.

METHODS

Ninety-eight athletes previously screened for EILO were invited for a follow-up CLE test irrespective of CLE scores and respiratory symptoms. Twenty-nine athletes aged 16-27 did a follow-up CLE test 3-23 months after the baseline test. Laryngeal obstruction at the glottic and supraglottic levels was graded by the observer during exercise, at baseline and follow-up, using a visual grade score (0-3 points).

RESULTS

At baseline, 11 (38%) of the 29 athletes had moderate laryngeal obstruction and received advice on breathing technique; among them, 8 (73%) reported exercise-induced dyspnea during the last 12 months. At follow-up, 8 (73%) of the athletes receiving advice on breathing technique had an unchanged supraglottic score. Three (17%) of the 18 athletes with no or mild laryngeal obstruction at baseline had moderate supraglottic obstruction at follow-up, and none of the 3 reported exercise-induced dyspnea.

CONCLUSIONS

In athletes with repeated testing, CLE scores remain mostly stable over 3-24 months even with advice on breathing technique to those with EILO. However, there is some intraindividual variability in CLE scores over time.

TRIAL REGISTRATION

ISRCTN, ISRCTN60543467, 2020/08/23, retrospectively registered, ISRCTN - ISRCTN60543467: Investigating conditions causing breathlessness in athletes.

Inducible Laryngeal Obstruction Differential Diagnosis in Adolescents and Adults: A Tutorial

Inducible laryngeal obstruction (ILO), formerly referred to as paradoxical vocal fold motion and vocal cord dysfunction, is a complex disorder of the upper airway that requires skillful differential diagnosis. There are several medical conditions that may mimic ILO (or which ILO may mimic) that should be considered in the differential diagnosis before evidence-supported behavioral intervention is initiated to mitigate or eliminate this upper airway condition. A key in treatment planning is determination of an isolated presentation of ILO or ILO concurrent with other conditions that affect the upper airway. Accurate, timely differential diagnosis in the clinical assessment of this condition mitigates delay of targeted symptom relief and/or insufficient intervention. Accurate assessment and nuanced clinical counseling are necessary to untangle concurrent, competing conditions in a single patient. This tutorial describes the common and rare mimics that may be encountered by medical professionals who evaluate and treat ILO, with particular attention to the role of the speech-language pathologist. Speech-language pathologists receive referrals for ILO from several different medical specialists (allergy, pulmonology, and sports medicine), sometimes without a comprehensive team assessment. It is paramount that speech-language pathologists who assess and treat this disorder have a solid understanding of the conditions that may mimic ILO. Summary tables that delineate differential diagnosis considerations for airway noise, origin of noise, symptoms, triggers, role of the speech-language pathologist, and β-agonist response are included for clinician reference. A clinical checklist is also provided to aid clinicians in the critical assessment process.

Reliability of trans-laryngeal airway resistance measurements during maximal exercise

Objective

: Exercised induced laryngeal obstruction (EILO) is an important cause of exertional dyspnea. The diagnosis rests on visual judgement of relative changes of the laryngeal inlet during continuous laryngoscopy exercise (CLE) tests, but we lack objective measures that reflect functional consequences. We aimed to investigate repeatability and normal values of trans-laryngeal airway resistance measured at maximal intensity exercise.

Methods

: Thirty-one healthy non-smokers without exercise related breathing problems were recruited. Participants performed two CLE tests enabling verified positioning of two pressure sensors, one at the tip of the epiglottis (supraglottic) and one by the fifth tracheal ring (subglottic). Airway pressure and flow data were continuously collected breath-by-breath and used to calculate trans-laryngeal resistance at peak exercise. Laryngeal obstruction was assessed according to a standardised CLE-score system.

Results

: Data from 26 participants (16 females) with two successful tests and equal CLE scores on both test-sessions were included in the trans-laryngeal resistance repeatability analyses. The coefficient of repeatability (CR) was 0.62 cmH2O·L−1·s−1, corresponding to a CR% of 21%. Mean (sd) trans-laryngeal airway resistance (cmH2O·L−1·s−1) in participants with no laryngeal obstruction (n=15) was 2.88 (0.50) in females and 2.18 (0.50) in males. Higher CLE scores correlated with higher trans-laryngeal resistance in females (r=0.81, p<0.001).

Conclusions

: This study establishes trans-laryngeal airway resistance obtained during exercise as a reliable parameter in respiratory medicine, opening the door for more informed treatment decisions and future research on the role of the larynx in health and disease.

Clinical responses following inspiratory muscle training in exercise-induced laryngeal obstruction

Purpose

Exercise-induced laryngeal obstruction (EILO) is relatively common in young people. Treatment rests on poor evidence; however, inspiratory muscle training (IMT) has been proposed a promising strategy. We aimed to assess laryngeal outcomes shortly after IMT, and to compare self-reported symptoms with a control group 4–6 years later.

Methods

Two groups were retrospectively identified from the EILO-register at Haukeland University Hospital, Norway; one group had received only information and breathing advice (IBA), and another additionally IMT (IBA + IMT). At diagnosis, all participants performed continuous laryngoscopy during exercise (CLE), with findings split by glottic and supraglottic scores, and completed a questionnaire mapping exercise-related symptoms. After 2–4 weeks, the IBA + IMT-group was re-evaluated with CLE-test. After 4–6 years, both groups were re-assessed with a questionnaire.

Results

We identified 116 eligible patients from the EILO-register. Response rates after 4–6 years were 23/58 (40%) and 32/58 (55%) in the IBA and IBA + IMT-group, respectively. At diagnosis, both groups rated symptoms similarly, but laryngeal scores were higher in the IBA + IMT-group (P = 0.003). After 2–4 weeks, 23/32 in the IBA + IMT-group reported symptom improvements, associated with a decrease of mainly glottic scores (1.7–0.3; P < 0.001), contrasting unchanged scores in the 9/32 without symptom improvements. After 4–6 years, exercise-related symptoms and activity levels had decreased to similar levels in both groups, with no added benefit from IMT; however, full symptom resolution was reported by only 8/55 participants.

Conclusion

Self-reported EILO symptoms had improved after 4–6 years, irrespective of initial treatment. Full symptom resolution was rare, suggesting individual follow-up should be offered.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00405-021-07214-5.

Modeling one-handed grip strangulation: Intentionality of the gesture and age influence

Strangulation is a violent act which can be lethal and is often studied in forensic context. The neck includes several anatomical elements that can evolve with aging. We therefore created a numerical human neck model including the main anatomical elements and simulated one-handed grip strangulation cases. In addition, we created 3 models each representing age groups: 20-30 years old, 30-50 years old and over 50 years old. The main changes between the different age groups are the ossification of the cartilages and the muscles mechanical properties. Several initial and boundary conditions have been tested to perform a realistic simulation of one-handed grip strangulation. Stress analysis and fracture observation were compared with the grip strength of an average man, 552 N, to look at the intentionality of the gesture. In each age group, the results show no model fracture for a force of 552 N. It is necessary to reach a minimum of 1406 N before observing a first fracture on the hyoid bone. However, it is possible to get stresses on the hyoid bone and on the thyroid cartilage way before 552 N. It thus appears that the force created by one-handed grip strangulation is not sufficient to cause fractures of the bony elements of the neck, but it remains sufficient to compress the larynx and at least reduce airflow.

Characteristics and impact of exercise-induced laryngeal obstruction: an international perspective

Background

Exercise-induced laryngeal obstruction (EILO) is a common cause of exertional breathlessness and wheeze yet is frequently misdiagnosed as asthma. Insight regarding the demographic characteristics, laryngeal abnormalities and impact of EILO is currently limited, with data only available from individual centre reports. The aim of this work was to provide a broader perspective from a collaboration between multiple international expert centres.

Methods

Five geographically distinct clinical paediatric and adult centres (3 Denmark, 1 UK, 1 USA) with an expertise in assessing unexplained exertional breathlessness completed database entry of key characteristic features for all cases referred with suspected EILO over a 5-year period. All included cases completed clinical asthma workup and continuous laryngoscopy during exercise (CLE) testing for EILO.

Results

Data were available for 1007 individuals (n=713 female (71%)) with a median (range) age of 24 (8–76) years, and of these 586 (58%) were diagnosed with EILO. In all centres, EILO was frequently misdiagnosed as asthma; on average there was a 2-year delay to diagnosis of EILO, and current asthma medication was discontinued in 20%. Collapse at the supraglottic level was seen in 60%, whereas vocal cord dysfunction (VCD) was only detected/visualised in 18%. Nearly half (45%) of individuals with EILO were active participants in recreational-level sports, suggesting that EILO is not simply confined to competitive/elite athletes.

Conclusion

Our findings indicate that key clinical characteristics and the impact of EILO/VCD are similar in globally distinct regions, facilitating improved awareness of this condition to enhance recognition and avoid erroneous asthma treatment.

Exercise-induced laryngeal obstruction is a prevalent cause of exertional breathlessness and wheeze. In this international multicentre collaboration, 1007 patients waited, on average, 2 years for diagnosis and 20% were mistreated as asthmatic.https://bit.ly/3auXpcp

Exercise-Associated Dyspnea and Stridor: Thinking Beyond Asthma

Breathlessness during sport can be caused by various cardiorespiratory conditions, but when associated with stridor, usually arises from an upper airway etiology. The term exercise-induced laryngeal obstruction (EILO) is now used to describe the phenomenon of transient glottic closure occurring in association with physical activity. Exercise-related laryngeal closure is most commonly encountered in athletic individuals and likely affects between 5% and 7% of all young adults and adolescents. The diagnosis of EILO is not always straightforward because features can overlap with exercise-induced asthma/exercise-induced bronchoconstriction. EILO can therefore remain misdiagnosed for years, and most patients receive inappropriate asthma therapy. In contrast with asthma, EILO symptoms are usually most prominent at maximal exercise intensity and resolve quickly on exercise cessation. It is important to recognize that EILO and asthma can coexist in a proportion of athletes. The criterion standard test for diagnosing EILO is continuous laryngoscopy during exercise testing, although eucapnic voluntary hyperpnea testing has also been used. Various surgical or pharmacological interventions can be used to treat EILO, but first-line treatment is breathing technique work. Further research is needed to establish the optimal treatment algorithm, and more work is needed to increase awareness of this important clinical entity.

The development of the cricoid cartilage and its implications for the use of endotracheal tubes in the pediatric population

BACKGROUND

The rigid cricoid cartilage is functionally the narrowest portion of the larynx. There is some controversy over the shape of the pediatric cricoid cartilage in the transverse plane. It is important to understand the development of the cricoid cartilage so that endo-traceheal tubes can be used more safely.

AIM

To determine changes in the internal diameter and shape of the cricoid cartilage during development and explore the implications of those changes for the selection of ETT type and size for children.

METHODS

The cervical computed tomography scans were reviewed in patients aged 1-20 years. After performing the multiplanar reconstruction and correcting the slant, the transverse and anteroposterior internal diameters of the inlet and outlet of the cricoid cartilage were measured, respectively. The angle between the arch and the lamina of the cricoid cartilage in the middle sagittal plane was measured. The ratios of transverse to anteroposterior diameter for the inlet and outlet of the cricoid cartilage were calculated, respectively.

RESULTS

In females, the internal diameters of the cricoid cartilage increased linearly with age. In males, the internal diameters of the cricoid cartilage exhibited a growth spurt during adolescence. The transverse diameter of the inlet was the smallest diameter of the cricoid cartilage, and the predicting formula of the transverse diameter of the inlet for children aged 1-12 was 0.4 × age (year) + 5.1, R²  = .758. The angle between the arch and lamina of the cricoid cartilage and the ratios of transverse to anteroposterior diameter correlated weakly with age.

CONCLUSION

The transverse inner diameter of the inlet is the smallest diameter of the cricoid cartilage. The "funnel shape" of the cricoid cartilage remains unchanged during development. The outer diameter should be considered when selecting an endotracheal tube.

Euclidean distances of laryngopharyngeal structures obtained from CT data for preclinical development of laryngoscopic devices

PURPOSE

This study aims to determine Euclidean distances between landmark structures in the larynx and pharynx to optimize endoscope shaft designs with regard to gentle and patient-oriented handling.

METHODS

Four Euclidean distances between landmarks in the larynx and pharynx were analyzed based on CT data of 66 patients. Distance (1): labium inferius oris-posterior pharyngeal wall at the cervical vertebra C1 (atlas), anterior edge of the tuberculum anterius atlantis. Distance (2): posterior pharyngeal wall adjacent to C1-entrance of pyriform sinus. Distance (3): inferior edge of the uvula-superior edge of the epiglottis. Distance (4): base of the vallecula-posterior pharyngeal wall. The minimum angular field of view α required to observe the glottis with a rigid transoral laryngoscope was derived trigonometrically from distances (2) and (4).

RESULTS

Average Euclidean distances measured: Distance (1): 90.7 mm ± 6.9 mm in men and 86.9 mm ± 5.9 mm in women. (2): 73.7 mm ± 13.4 mm and 56.2 mm ± 7.6 mm. (3): 25.2 mm ± 8.6 mm and 18.5 mm ± 6.8 mm. (4): 20.8 mm ± 4.6 mm and 16.5 mm ± 3.4 mm. α: 16.0° ± 3.9° and 16.6 ± 4.3°.

CONCLUSIONS

As expected, statistically significant sex-related differences could be observed for distances (1)-(4). The results indicate that the length of transoral laryngoscopes should not be below 110 mm and that a minimum angular field of view of α = 17° is required to fully observe the laryngeal inlet.

Corner vowels in males and females ages 4 to 20 years: Fundamental and F1-F4 formant frequencies

The purpose of this study was to determine the developmental trajectory of the four corner vowels' fundamental frequency (f_o) and the first four formant frequencies (F1-F4), and to assess when speaker-sex differences emerge. Five words per vowel, two of which were produced twice, were analyzed for f_o and estimates of the first four formants frequencies from 190 (97 female, 93 male) typically developing speakers ages 4-20 years old. Findings revealed developmental trajectories with decreasing values of f_o and formant frequencies. Sex differences in f_o emerged at age 7. The decrease of f_o was larger in males than females with a marked drop during puberty. Sex differences in formant frequencies appeared at the earliest age under study and varied with vowel and formant. Generally, the higher formants (F3-F4) were sensitive to sex differences. Inter- and intra-speaker variability declined with age but had somewhat different patterns, likely reflective of maturing motor control that interacts with the changing anatomy. This study reports a source of developmental normative data on f_o and the first four formants in both sexes. The different developmental patterns in the first four formants and vowel-formant interactions in sex differences likely point to anatomic factors, although speech-learning phenomena cannot be discounted.

Exercise-induced laryngeal obstruction (EILO) in children and young adults: From referral to diagnosis

OBJECTIVE

To identify different presentations, referral patterns, comorbidities, and laryngoscopy findings in children and young adults with exercise-induced laryngeal obstruction (EILO).

METHODS

We performed a retrospective chart review of 112 patients, age <26 years, with EILO between 2013 and 2016.

RESULTS

Of the 112 patients who met criteria, 91 were female and 21 were male. Patients were most frequently referred by pulmonologists (60.7%). The majority of patients (93%) participated in organized sports, most of them at a competitive level. The mean age at symptom onset was 13.8 ± 3.3 years, and the mean age of diagnosis was 15.4 ± 3.0 years. Sixty-seven (59.8%) patients presented with a prior diagnosis of asthma, the majority of whom had failed asthma treatment. The most common symptoms reported were dyspnea (93.8%), wheezing/stridor (78.6%), and throat tightness (48.2%). Ninety-one (81.3%) patients had spirometry performed, with 46 (51.1%) showing inspiratory loop flattening. On flexible laryngoscopy, 87 (78.4%) of 111 patients had paradoxical vocal fold motion. Supraglottic involvement was observed to obstruct the airway in 26 (23.9%) patients, with patterns of obstruction similar to those observed in children with laryngomalacia.

CONCLUSION

Most patients participated in competitive sports, were female, and presented with exertional dyspnea. Most patients were diagnosed with exercise-induced asthma but treated unsuccessfully. Almost one-quarter of our patients showed supraglottic collapse obstructing the airway. Exercise-induced laryngeal obstruction is a more descriptive term than paradoxical vocal fold motion or vocal cord dysfunction, which only describe vocal fold involvement. The time to diagnosis of EILO was shorter than previously reported, suggesting that awareness of this condition is increasing.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:E400-E406, 2020.

Biomechanical study of the thyroid cartilage: A model of bi-digital strangulation

The presence of fracture on neck elements is an indication of violence. Both the hyoid bone and the larynx can be damaged by a strangulation mechanism. Thyroid cartilage, more specifically, may present lesions in response to this mechanical stress. These lesions result in fractures at the bases of the horns of the thyroid cartilage. This study focuses on the thyroid cartilage behavior in cases of bi-digital strangulation, using an anthropometric and biomechanical approach. To develop a biomechanical model, we performed an anthropometric study taking into account 14 distances measurements as well as 3 measurements of angles. These measures allowed us to determine a significant sexual dimorphism between individuals. Then, we define 6 morphologies models, composed of 3 females and 3 males individuals. In order to visualize the ossification of the cartilage, each model has been tested with bone properties. Strangulation cases were simulated by applying an imposed velocity of 0.4m/s then 1m/s. We observed different behaviors of the thyroid cartilage according to the sex and the morphology.

Severe Exercise-Induced Laryngeal Obstruction Treated With Supraglottoplasty

Introduction: Exercise induced laryngeal obstruction (EILO) is relatively common in adolescents, with symptoms often confused with exercise induced asthma. EILO often starts with medial or inward rotation of supraglottic structures of the larynx, whereas glottic adduction appears as a secondary phenomenon in a majority. Therefore, surgical treatment (supraglottoplasty) is used in thoroughly selected and highly motivated patients with pronounced symptoms and severe supraglottic collapse.

Aim: To investigate efficacy and safety of laser supraglottoplasty as treatment for severe supraglottic EILO by retrospective chart reviews.

Methods: The EILO register at Haukeland University Hospital, Bergen, Norway was used to identify patients who had undergone laser supraglottoplasty for severe supraglottic EILO, verified by continuous laryngoscopy exercise (CLE) test, during 2013–2015. Laser incision in both aryepiglottic folds anterior to the cuneiform tubercles and removal of the mucosa around the top was performed in general anesthesia. Outcomes were questionnaire based self-reported symptoms, and laryngeal obstruction scored according to a defined scheme during a CLE-test performed before and after surgery.

Results: Forty-five of 65 eligible patients, mean age 15.9 years, were included. Post-operatively, 38/45 (84%) patients reported less symptoms, whereas CLE-test scores had improved in all, of whom 16/45 (36%) had no signs of obstruction. Most improvements were at the supraglottic level, but 21/45 (47%) also improved at the glottic level. Two of 65 patients had complications; self-limiting vocal fold paresis and scarring/shortening of plica ary-epiglottica.

Conclusion: Supraglottoplasty improves symptoms and decreases laryngeal obstruction in patients with severe supraglottic EILO, and appears safe in highly selected cases.

Physiotherapy improves symptoms of exercise-induced laryngeal obstruction in young elite athletes: a case series

OBJECTIVE

A constricted, upper chest breathing pattern and postural dealignments habitually accompany exercise-induced laryngeal obstruction (EILO), but there are few effective treatments for athletes presenting with EILO. This case series was conducted to examine whether physiotherapy based on principles from the Norwegian psychomotor physiotherapy (NPMP) combined with elements of cognitive behavioural therapy can reduce laryngeal distress in athletes with EILO.

METHODS

Respiratory distress in four subjects was examined by interview prior to a physiotherapeutic body examination. Inappropriate laryngeal movements during exercise were measured by the continuous laryngoscopy exercise test, lung function was measured by flow-volume curves, and non-specific bronchial hyper-responsiveness was measured by a methacholine provocation test. History of asthma, allergy and respiratory symptoms was recorded in a modified AQUA2008 questionnaire. Parasympathetic activity was assessed by pupillometry. All data were gathered before and after 5 months of intervention.

RESULTS

Physiotherapy based on the principles from NPMP improved breathing problems in athletes with EILO. All athletes had less respiratory distress, improved lung function at rest and reduced inappropriate laryngeal movements during maximal exercise.

CONCLUSION

A diaphragmatic breathing pattern, a more balanced tension in respiratory muscles, and sound cervical alignment and stability may help to reduce adverse stress on the respiratory system and optimise the function of the larynx during high-intensity exercise. Our results suggest that understanding and management of EILO need to extend beyond structures located in the anterior neck and include factors influencing the whole respiratory system.

Exercise-Induced Laryngeal Obstruction: When Pediatric Exertional Dyspnea Does not Respond to Bronchodilators

Exertional dyspnea is a common complaint in general pediatric practice. While a high proportion of the general pediatric population has asthma, other diagnoses, including exercise-induced laryngeal obstruction should be considered, especially when asthma therapy is not sufficient to control symptoms. This review describes some of the key clinical features of exercised-induced laryngeal obstruction as well as preferred diagnostic and therapeutic approaches. Importantly, current diagnostic technology has considerably improved in the last decade at specialty centers. At the same time, infrastructure for clinical trials is emerging and there is not strong evidence to support specific therapies at the current time.

Airway dimensions from fetal life to adolescence-A literature overview

BACKGROUND

Data on airway dimensions in pediatric patients are important for proper selection of pediatric airway equipment such as endotracheal tubes, double-lumen tubes, bronchial blockers, or stents. The aim of the present work was to provide a synopsis of the available data on pediatric airway dimensions.

METHODS

A systematic literature search was carried out in the PubMed database, Scopus, Embase, Web of Science, Prisma, and Google Scholar and secondarily completed by a reference search. Based on inclusion and exclusion criteria, a final selection of 109 studies with data on pediatric airway dimensions published from 1923 to 2018 were further analyzed.

RESULTS

Six different airway measurement methods were identified. They included anatomical examinations, chest X-ray, computed tomography, magnetic resonance tomography, bronchoscopy, and ultrasound. Anatomical studies were more abundant compared to other methods. Data provided were very heterogeneously presented and powered. In addition, due to different study conditions, they are hardly comparable. Among all, anatomical and computer tomography studies are thought to provide the most reliable data. Ultrasound is an upcoming technique to estimate airway parameters of fetus and premature infants. There was, in general, a lack of comprehensive studies providing a complete range of airway dimensions in larger groups of patients from birth to adolescence.

CONCLUSIONS

This work revealed a large heterogeneity of studies providing data on pediatric airway dimensions, making it impossible to compare, or assemble them to normograms for clinical use. Comprehensive studies in large population of children are needed to provide full range nomograms on pediatric airway dimensions.

Exercise-induced laryngeal obstruction in athletes: Contributory factors and treatment implications

Otherwise healthy adolescent athletes presenting with respiratory symptoms consistent with exercise-induced laryngeal obstruction (EILO) are frequently encountered in clinical practice. The symptoms are often incorrectly considered to result from exercise-induced asthma, and may be wrongly treated as such. Given the potential implications for health and performance if EILO is left untreated, a more comprehensive understanding of contributory mechanisms is essential in order to create appropriate treatment procedures. Informed by knowledge from physical therapy, as well as the fields of voice rehabilitation and vocal pedagogy, this theoretical article presents a novel way of understanding and managing EILO by exploring bodily mechanisms and structures that may disturb laryngeal function during strenuous exercise. Firstly, the status quo of the EILO diagnosis, its aetiology and treatment options are reviewed. Secondly, considerations associated with laryngeal structures and mechanisms, and their potential influence on laryngeal movement and sensitivity are examined. Thirdly, the manner in which postural de-alignment and breathing pattern may interfere with laryngeal functioning will be discussed. Finally, interventions for voice disorders and singing and the relevance of these for EILO are evaluated. It is argued that clients with EILO should undergo a thorough physical examination to identify constrictions in the body as a whole - such as postural de-alignments and a dysfunctional breathing pattern - as these are hypothesized as playing a critical role in laryngeal tightness during exercise. Physical therapists possess particular skills and competence with regard to examining breathing patterns and postural de-alignments, and should be included in the treatment process of EILO.

Exercise-Induced Laryngeal Obstruction-An Overview

Exertional dyspnea is common in health and disease. Despite having known for centuries that breathlessness can arise from the larynx, exercise-induced laryngeal obstruction is a more prevalent condition than previously assumed. This article provides a brief overview of the history, epidemiology, and pathophysiology of exercise-induced laryngeal obstruction.

Laryngeal sensitivity testing in youth with exercise-inducible laryngeal obstruction

Exercise-inducible laryngeal obstruction (EILO) has been recognized as a not rare respiratory problem in youth practicing sports. The aim of the study was to test the mechanosensitivity of the larynx, and to identify the factors affecting it in a group of youth with proven EILO. Laryngeal sensory testing was performed in 54 adolescents and young adults with EILO. Laryngeal mucosal alterations were assessed according to the Reflux Finding Score (RFS). The data concerning diseases possibly affecting the upper airway, findings of previously performed flexible videolaryngoscopy during exercise, and RFS score were compared between the participants with laryngeal hyposensitivity and those with normal sensitivity. The participants with isolated vocal folds' adduction during an EILO attack were compared with those who demonstrated supraglottis collapse. Testing revealed an increased threshold for mechanical stimuli in 81.5% of participants. Among participants with hyposensitivity, there were significantly more participants with dysphagia during EILO attacks than among the participants with normal laryngeal sensitivity. The hyposensitivity group had a significantly higher RFS score compared with the other group. Isolated vocal folds' approximation was only observed in 11.9% of participants. These participants were younger and had asthma more frequently compared with the others. Only 16.9% of participants with EILO did not state symptoms related to gastroesophageal reflux. The decreased mechanosensitivity was detected in the majority of participants, suggesting that laryngopharyngeal reflux can be an important etiological factor. The problem of breathing difficulties during sport activities in youth can also be associated with the disproportionate growth of the respiratory tract.

Exercise inducible laryngeal obstruction: diagnostics and management

Obstruction of the central airways is an important cause of exercise-induced inspiratory symptoms (EIIS) in young and otherwise healthy individuals. This is a large, heterogeneous and vastly understudied group of patients. The symptoms are too often confused with those of asthma. Laryngoscopy performed as symptoms evolve during increasing exercise is pivotal, since the larynx plays an important role in symptomatology for the majority. Abnormalities vary between patients, and laryngoscopic findings are important for correct treatment and handling. The simplistic view that all EIIS is due to vocal cord dysfunction [VCD] still hampers science and patient management. Causal mechanisms are poorly understood. Most treatment options are based on weak evidence, but most patients seem to benefit from individualised information and guidance. The place of surgery has not been settled, but supraglottoplasty may cure well-defined severe cases. A systematic clinical approach, more and better research and randomised controlled treatment trials are of utmost importance in this field of respiratory medicine.

Larynx during exercise: the unexplored bottleneck of the airways

Exercise-induced shortness of breath is not uncommon in otherwise healthy young people. Based on the presenting symptoms alone, it is challenging to distinguish exercise-induced asthma (EIA) from exercise-induced obstruction of central airways, sometimes leading to diagnostic errors and inadequate treatment. Central airway obstruction usually presents with exercise-induced inspiratory symptoms (EIIS) during ongoing exercise. EIIS tends to peak towards the end of an exercise session or immediately after its completion, contradicting symptoms of EIA typically peaking 3-15 min after the exercise has stopped. EIIS is usually associated with some form of laryngeal obstruction. Transnasal flexible laryngoscopy performed continuously throughout an incremental exercise test from rest to exhaustion or to intolerable symptoms is usually diagnostic, and also provides information that is important for further handling and treatment. Reflecting the complex anatomy and functional features of the larynx, exercise-induced laryngeal obstruction (EILO) appears to be a heterogeneous condition. Contradicting previous beliefs, recent literature suggests that laryngeal adduction in a majority of cases starts in supraglottic structures and that vocal cord adduction (VCD) most often occurs as a secondary phenomenon. However, EILO is poorly understood and more and better research is needed to unravel causal mechanisms. The evidence base for treatment of EILO is weak. Speech therapy, psychotherapy, biofeedback, muscle training, anticholinergic aerosols have all been applied, as has laser supraglottoplasty. Randomized controlled trials with well-defined and verifiable inclusion and success criteria are required to establish evidence-based treatment schemes.

The accuracy of locating the cricothyroid membrane by palpation - an intergender study

Background

The cricothyroid membrane (CTM) is the recommended site of access to the airway during cricothyrotomy to provide emergency oxygenation. We sought to compare the ability of physicians to correctly identify the CTM in male and female patients.

Methods

In a prospective observational study, anaesthetists were asked to locate the CTM by palpation which was then identified using ultrasound and the distance between the actual and estimated margin of the CTM was measured. Participants assessed the ease of CTM palpation using a visual analog scale. In a second series, the angulation of the posterior junction of the thyroid laminae was measured using ultrasound.

Results

23 anaesthetists and 44 subjects participated. A total of 36 assessments were carried out in each gender. Incorrect identification of the CTM was more common in females (29/36 vs. 11/36, P < 0.001) and the distance from the CTM in the vertical plane was greater (11.0 [6.5–20.0] vs. 0.0 [0.0–10.0] mm, P < 0.001). In females distance from the CTM correlated positively with neck circumference (P = 0.005) and BMI (P = 0.00005) and negatively with subject height (P = 0.01). Posterior thyroid cartilage angulation was greater in females (118.6 ± 9.4° vs. 95.9 ± 12.9°, P = 0.02) and was lower in patients with correctly identified CTMs (100.0 ± 14.9° vs. 115.6 ± 15.9°, P = 0.02). VRS palpation correlated with decreased posterior thyroid cartilage angulation (P = 0.04).

Conclusions

CTM localisation is more difficult in female subjects irrespective of body habitus. It may be prudent to localize this structure by additional means (e.g. ultrasound) in advance of any airway manoeuvres or to modify the cricothyrotomy technique in the event that it is necessary in an emergency.

Habitual snoring in school-aged children: environmental and biological predictors

Background

Habitual snoring, a prominent symptom of sleep-disordered breathing, is an important indicator for a number of health problems in children. Compared to adults, large epidemiological studies on childhood habitual snoring and associated predisposing factors are extremely scarce. The present study aimed to assess the prevalence and associated factors of habitual snoring among Chinese school-aged children.

Methods

A random sample of 20,152 children aged 5.08 to 11.99 years old participated in a cross-sectional survey, which was conducted in eight cities of China. Parent-administrated questionnaires were used to collect information on children's snoring frequency and the possible correlates.

Results

The prevalence of habitual snoring was 12.0% (14.5% for boys vs. 9.5% for girls) in our sampled children. Following factors were associated with an increased risk for habitual snoring: lower family income (adjusted odds ratio [OR] = 1.46), lower father's education (OR = 1.38 and 1.14 for middle school or under and high school of educational level, respectively), breastfeeding duration < 6 months (OR = 1.17), pregnancy maternal smoking (OR = 1.51), obesity (OR = 1.50), overweight (OR = 1.35), several respiratory problems associated with atopy and infection, such as chronic/allergic rhinitis (OR = 1.94), asthma (OR = 1.43), adenotonsillar hypertrophy (OR = 2.17), and chronic otitis media (OR = 1.31), and family history of habitual snoring (OR = 1.70).

Conclusion

The prevalence of habitual snoring in Chinese children was similar to that observed in other countries. The potential predisposing factors covered socioeconomic characteristics, environmental exposures, chronic health problems, and family susceptibility. Compared to socioeconomic status and family susceptibility, environmental exposures and chronic health problems had greater impact, indicating childhood habitual snoring could be partly prevented by health promotion and environmental intervention.