Congenital glottic stenosis as a clinical manifestation of FREM1-associated disorders in a neonate with respiratory distress and aphonia.

A female infant born at 38 weeks and 2 days via induced vaginal delivery was admitted to the neonatal intensive care unit for respiratory distress soon after birth. Noted to have aphonia on examination, the patient underwent direct laryngoscopy and was diagnosed with an anterior glottic web and subglottic stenosis. The patient underwent a genetic workup including whole exome sequencing which resulted in a diagnosis of a FREM1-associated disorder. Congenital glottic webs and subglottic stenoses have not been previously described as clinical manifestations of FREM1-associated disorders.

Double lumen endobronchial tube intubation: lessons learned from anatomy.

BACKGROUND: Double lumen endobronchial tubes (DLTs) are frequently used to employ single lung ventilation strategies during thoracic surgical procedures. Placement of these tubes can be challenging even for experienced clinicians. We hypothesized that airway anatomy, particularly of the glottis and proximal trachea, significantly impacts the ease or difficulty in placement of these tubes. METHODS: Images from 24 randomly selected Positron Emission Tomography - Computed Tomography (PET-CT) scans were evaluated for several anatomic aspects of the upper airway, including size and angulation of the glottis and proximal tracheal using calibrated CT measurements and an online digital protractor. The anatomic issues identified were confirmed in cadaveric anatomic models. RESULTS: Proximal tracheal diameter measurements in PET-CT scans demonstrated a mean ± standard deviation of 20.4 ± 2.5 mm in 12 males and 15.5 ± 0.98 mm in 12 females (p < 0.001), and both were large enough to accommodate 39 French and 37 French DLTs in males and females, respectively. Subsequent measurements of the posterior angulation of the proximal trachea revealed a mean angle of 40.8 ± 5.7 degrees with no sex differences. By combining the 24 individual posterior tracheal angles with the 16 angled distal tip measurements DLTs (mean angle 24.9 ± 2.1 degrees), we created a series of 384 patient intubation angle scenarios. This data clearly showed that DLT rotation to a full 180 degrees decreased the mean intubation angle between the DLT and the proximal trachea from a mean of 66.6 ± 5.9 to only 15.8 ± 5.9 degrees. CONCLUSIONS: Rotation of DLTs a full 180 instead of the recommended 90 degrees facilitates DLT intubations.

[Analysis of vocal fold movement characteristics in patients with laryngeal neurogenic injury].

Objective:To analyze the characteristics of vocal fold movement and glottic closure in patients with laryngeal neurogenic injury. Methods:A total of 185 patients with vocal fold paralysis diagnosed by laryngeal electromyography as neurogenic damage to cricothyroid muscle, thyreoarytenoid muscle and posterior cricoarytenoid muscle were enrolled, they were divided into unilateral vocal fold paralysis group and bilateral vocal fold paralysis group, respectively, and superior laryngeal paralysis group, recurrent laryngeal nerve paralysis group and vagal nerve paralysis group according to nerve injury. The characteristics of vocal fold movement and glottic closure were analyzed under strobe laryngoscope. The qualitative evaluation of vocal fold movement was fixed vocal fold, reduced vocal fold movement and normal vocal fold movement, and the qualitative evaluation of glottic closure was glottic closure and glottic imperfection. The results were analyzed statistically. Results:The proportion of normal, reduced and fixed vocal fold motion in bilateral vocal fold paralysis group was significantly different from that in unilateral vocal fold paralysis group（P<0.05）, the composition of normal and reduced vocal fold motion in bilateral vocal fold paralysis group（47.70%） was significantly greater than that in unilateral vocal fold paralysis group（12.27%）. There was no significant difference between the proportion of glottic closure and glottic imperfecta in bilateral vocal fold paralysis group and unilateral vocal fold paralysis group（P<0.05）. The proportion of decreased vocal fold motion in superior laryngeal nerve paralysis group（50.00%） was higher than that in recurrent laryngeal nerve paralysis group（9.32%） and vagal nerve paralysis group（9.00%）. The proportion of decreased and fixed vocal fold motion in superior laryngeal nerve paralysis group, recurrent laryngeal nerve paralysis group and vagal nerve paralysis group was statistically significant（P<0.05）.There was no significant difference in glottic closure among the three groups（P<0.05）. Conclusion:Vocal fold movement characteristics of patients with laryngeal neurogenic injury were mainly vocal fold fixation, or normal or weakened vocal fold movement. There may be missed diagnosis of unilateral vocal fold paralysis in clinical practice. In half of the patients with superior laryngeal nerve palsy, vocal fold movement is characterized by vocal fold fixation.

PET/CT findings and dose distribution during radiotherapy in T1N0M0-T2N0M0 glottic cancer.

OBJECTIVE: To investigate the positron emission tomography/computed tomography (PET/CT) findings of T1/T2N0M0 glottic cancer (hereafter referred to as T1/T2) and dose distribution in radiotherapy. SUBJECTS AND METHODS: We retrospectively collected data from patients diagnosed with T1/T2N0M0 glottic cancer who received radiotherapy. The extent of fluorine-18-fluorodeoxyglucose (18F-FDG) accumulation in primary tumors, maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), tumor volume of primary tumors on PET/CT were compared. Furthermore, the tumor identified on PET/CT was incorporated into the radiotherapy plans. A dummy plan (radiation field 6x6cm, prescription point facing the vertebral body, maximum dose ≤107%, T1/T2 66Gy/33 fractions) was developed for three-dimensional conformal radiotherapy, and the dose distribution of primary tumors was calculated. RESULTS: Twenty-nine patients (27 men and two women) were included; their mean age was 67.2±15.0 years. Increased 18F-FDG accumulation in primary tumors was observed on PET/CT in 22/29 (78.5%; T1: 14/21 [67%], T2: 8/8 [100%]) patients. The median SUVmax, TLG, and primary tumor volume were significantly different between T1 and T2 (SUVmax, T1: 4.56 vs. T2: 8.43, P=0.035; TLG, T1: 1.01 vs. T2: 3.71 SUVxmL, P<0.01; primary tumor volume, T1: 0.38mL vs. T2: 0.80mL, P=0.01). At a TLG cut-off value of 3.470, the area under the curve was 0.875, sensitivity was 0.875, and specificity was 0.929 for T1-T2 differentiation. In 20 patients with 18F-FDG accumulation, the minimum radiation dose was significantly different between T1 and T2 (66Gy vs. 64Gy, P<0.01) at the same 66Gy prescription. The minimum radiation dose and primary tumor volume show the correlation value (r=-0.516, P=0.02). CONCLUSION: In glottic cancer, T1 and T2 can be differentiated by the extent of 18F-FDG accumulation in primary tumors on PET/CT. The minimum radiation dose rate decreases as volume increases.

Dosimetric comparison between carotid-sparing IMRT and 3DCRT in early glottic cancer patients treated with definitive radiation therapy.

BACKGROUND: The purpose of this study was to evaluate the dosimetric benefits of carotid-sparing IMRT (intensity-modulated radiation therapy) over 3DCRT (three-dimensional conformal radiation therapy) in early glottic cancer patients. MATERIAL AND METHODS: Ten patients with histologically proven early-stage squamous cell cancer of glottis (T1N0), treated with definitive radiotherapy, were selected retrospectively for the dosimetric analysis. Patients were originally treated with 3DCRT technique. For comparison purpose, IMRT plans were generated for each patient. Dosimetric comparison was done between two techniques (IMRT and 3DCRT) in terms of PTV (planning target volume) coverage, HI (homogeneity index), CI (conformity index), and doses to right carotid artery, left carotid artery, and spinal cord. RESULTS: V95% for the PTV was higher in IMRT plans (98.26%) as compared to 3DCRT plans (95.12%) (P-value <0.001), whereas V105% for PTV was significantly higher in 3DCRT plans (16.77%) as compared to IMRT plans (0.32%) (P-value 0.11). In terms of both HI and CI, IMRT plans showed better conformity as compared to 3DCRT plans, with statistically significant difference. Both right and left carotid arteries' average mean and maximum doses were significantly lower in IMRT plans as compared to 3DCRT plans (P-value <0.001). IMRT plans resulted in significant carotid-sparing as compared to 3DCRT plans in terms of V35 and V50 (P-value <0.001). CONCLUSION: Carotid-sparing IMRT resulted in better PTV coverage and lower carotid artery dose as compared to 3DCRT in early glottic cancer patients.

Assessment and validation of glottic motion using cone-beam CT and real-time cine MRI.

PURPOSE: This study aimed to assess the margin for the planning target volume (PTV) using the Van Herk formula. We then validated the proposed margin by real-time magnetic resonance imaging (MRI). METHODS: An analysis of cone-beam computed tomography (CBCT) data from early glottic cancer patients was performed to evaluate organ motion. Deformed clinical target volumes (CTV) after rigid registration were acquired using the Velocity program (Varian Medical Systems, Palo Alto, CA, USA). Systematic (Σ) and random errors (σ) were evaluated. The margin for the PTV was defined as 2.5 Σ + 0.7 σ according to the Van Herk formula. To validate this margin, we accrued healthy volunteers. Sagittal real-time cine MRI was conducted using the ViewRay system (ViewRay Inc., Oakwood Village, OH, USA). Within the obtained sagittal images, the vocal cord was delineated. The movement of the vocal cord was summed up and considered as the internal target volume (ITV). We then assessed the degree of overlap between the ITV and the PTV (vocal cord plus margins) by calculating the volume overlap ratio, represented as (ITV∩PTV)/ITV. RESULTS: CBCTs of 17 early glottic patients were analyzed. Σ and σ were 0.55 and 0.57 for left-right (LR), 0.70 and 0.60 for anterior-posterior (AP), and 1.84 and 1.04 for superior-inferior (SI), respectively. The calculated margin was 1.8 mm (LR), 2.2 mm (AP), and 5.3 mm (SI). Four healthy volunteers participated for validation. A margin of 3 mm (AP) and 5 mm (SI) was applied to the vocal cord as the PTV. The average volume overlap ratio between ITV and PTV was 0.92 (range 0.85-0.99) without swallowing and 0.77 (range 0.70-0.88) with swallowing. CONCLUSION: By evaluating organ motion by using CBCT, the margin was 1.8 (LR), 2.2 (AP), and 5.3 mm (SI). The margin acquired using CBCT fitted well in real-time cine MRI. Given that swallowing during radiotherapy can result in a substantial displacement, it is crucial to consider strategies aimed at minimizing swallowing and related motion.

Acoustic outcomes and voice-related quality of life in male-to-female transsexuals undergoing Wendler glottoplasty: a single-centre experience.

INTRODUCTION: Many transsexual women seek to feminise their voice through pitch elevation surgeries so that it becomes congruent with their gender identity. This study aims to determine the safety and effectiveness of Wendler glottoplasty (WG) in vocal feminisation through the assessment of acoustic and aerodynamic parameters of the voice, as well as voice-related quality of life (QoL) in male-to-female transsexuals. MATERIAL AND METHODS: We retrospectively reviewed the medical records of transsexual women who underwent WG for voice feminisation at our institution between 2016 and 2023. All acoustic and aerodynamic analyses, a voice self-assessment, and a videolaryngostroboscopic evaluation were performed in the immediate preoperative period and at the follow-up visit 6 weeks after the procedure. RESULTS: A total of 11 patients with a mean age of 32.73 years were included. After WG, there was a significant fundamental frequency and speaking fundamental frequency increase of 109.64 Hz and 83.48 Hz, respectively (p < 0.001), representing an average rise by 9.71 semitones and 8.36 semitones (STs), respectively. No significant differences were found between the mean pre- and postoperative values of fundamental frequencies, frequency range, upper limit of the frequency range of spoken voice, and maximum phonation time. Contrarily, the mean lower limit of frequency range rose by 75.56 Hz (p < 0.001), representing an average increase of 10.56 STs. None of the assessed spirometric parameters changed significantly after WG (p > 0.05). The mean overall Voice Handicap Index (VHI) and Voice-Related Quality of Life (V-RQOL) scores significantly improved after the surgery, decreasing by 24.54 points (p = 0.008) and 11.5 points (p = 0.001), respectively. A significant improvement was observed in the functional and emotional domains of VHI. Additionally, significantly fewer patients considered the overall quality of their voice to be "poor" after WG. CONCLUSIONS: WG constitutes an effective method of surgical voice feminisation in male-to-female transsexuals with concurrent improvement in their voice-related QoL. Furthermore, it remains a safe procedure without persistent complications and negative influence on the acoustic-aerodynamic measures of the voice.

Isoprognostic functional CT map for open partial horizontal laryngectomy.

PURPOSE: To identify a radiological map of laryngeal subsites whose involvement by the tumor could predict patients' functional outcomes after open partial horizontal laryngectomy (OPHL). METHODS: The present retrospective analysis concerned 96 patients with glottic squamous cell carcinoma, who were radiologically staged with contrast-enhanced neck CT scans before undergoing supracricoid or supratracheal laryngectomy. A radiological map of patients' functional risk was developed by considering the distribution of functional outcomes in relation to the laryngeal subsites involved. The functional outcomes considered were: (i) decannulation at discharge; (ii) time to removal of the nasogastric feeding tube (NFT); (iii) postoperative complication rate; and (iv) length of hospital stay. RESULTS: Involvement of the anterior supraglottis was related to a longer need for NFT, and a longer hospital stay (p = 0.003, and p = 0.003, respectively). Involvement of the posterior glottis negatively affected the time to decannulation, and the likelihood of postoperative complications (p = 0.000, and p = 0.002, respectively). CONCLUSIONS: Anterior glottic small tumors (without significant subglottic and/or supraglottic extension) are related to the best functional outcomes after OPHL, since the suprahyoid epiglottis and both the arytenoids are likely to be spared.

Transoral laser microsurgery for T1 glottic cancer with anterior commissure: Identifying clinical and radiological variables that predict oncological outcome.

PURPOSE: The involvement of the anterior commissure (AC) is regarded to be a risk factor for poor results after transoral laser microsurgery (TLM) for early glottic cancer. The objective of this study was to determine how AC-related clinical and radiological factors affected oncological outcomes in a cohort of patients with T1 stage early glottic carcinoma involving the anterior commissure who were treated with TLM with negative surgical margins. METHODS: Retrospective analysis was performed on clinical, radiological, and follow-up data of patients consecutively treated with TLM at a tertiary academic center between November 2011 and August 2021 for T1 glottic squamous cell carcinoma involving the anterior commissure. Recurrence-free survival (RFS), local control with laser alone (LCL), laryngeal preservation (LP), and overall survival (OS) rates (Kaplan-Meier) were the primary outcome metrics. RESULTS: In our series, 5-year OS probability was 75.1%, RFS was 64.8%, LCL was 73.8%, and LP was 83.4%. OS and RFS were higher in patients with early stages of AC pattern than in patients with advanced stage (p = 0.004, p = 0.034, respectively). Vertical extension ratio was found to be associated with OS and RFS (p = 0.023, p = 0.001, respectively), and thyroid cartilage interlaminar angle with LCL by multiple Cox regression analysis (p = 0.041). CONCLUSION: TLM remains a valuable treatment option for AC involvement. AC3 type involvement and elevated vertical extension ratio were associated with negative prognosis. There have been signs that thyroid cartilage with a narrow angle increases recurrence. Alternative modalities should be kept in mind in the treatment decision of these cases.

Simulation of Multiple Source Vocalization in the Larynx: How True Folds, False Folds, and Aryepiglottic Folds May Interact.

PURPOSE: This study was a modest beginning to determine dominance and entrainment between three soft tissues in the larynx that can be set into flow-induced oscillation and act as sound sources. The hypothesis was that they interact as coupled oscillators with observable bifurcations as energy is exchanged between them. METHODOLOGY: The true vocal folds, the ventricular (false) folds, and the aryepiglottic folds were part of a soft-walled airway that produced airflow for sound production. The methodology was computational, based on a simplified Navier-Stokes solution of convective and compressible airflow in a variable-geometry airway. RESULTS: Three serially connected sources could all produce flow-induced self-oscillation with soft wall tissue and small cross-sectional area. When the glottal cross-sectional areas were similar, bifurcations such as subharmonics, delayed voice onset, and aphonia occurred in the coupled oscillations. CONCLUSIONS: Closely spaced sound sources in the larynx are highly interactive. They appear to entrain to the source that has the combined advantage of small cross-sectional glottal area and proximity to a downstream vocal tract that supports oscillation with acoustic inertance.

Acoustics and aerodynamic effects following glottal and infraglottal medialization in an excised larynx model.

OBJECTIVE: This study aimed to investigate the impact of the implant's vertical location during Type 1 Thyroplasty (T1T) on acoustics and glottal aerodynamics using excised canine larynx model, providing insights into the optimal technique for treating unilateral vocal fold paralysis (UVFP). METHODS: Measurements were conducted in six excised canine larynges using Silastic implants. Two implant locations, glottal and infraglottal, were tested for each larynx at low and high subglottal pressure levels. Acoustic and intraglottal flow velocity field measurements were taken to assess vocal efficiency (VE), cepstral peak prominence (CPP), and the development of intraglottal vortices. RESULTS: The results indicated that the implant's vertical location significantly influenced vocal efficiency (p = 0.045), with the infraglottal implant generally yielding higher VE values. The effect on CPP was not statistically significant (p = 0.234). Intraglottal velocity field measurements demonstrated larger glottal divergence angles and stronger vortices with the infraglottal implant. CONCLUSION: The findings suggest that medializing the paralyzed fold at the infraglottal level rather than the glottal level can lead to improved vocal efficiency. The observed larger divergence angles and stronger intraglottal vortices with infraglottal medialization may enhance voice outcomes in UVFP patients. These findings have important implications for optimizing T1T procedures and improving voice quality in individuals with UVFP. Further research is warranted to validate these results in clinical settings.

Minimal invasive LASER-resection vs. radiotherapy as primary treatment of early glottic cancer. A population-based study with, up to 16 years follow up of survival, rate of laryngectomy and voice function.

BACKGROUND: Early glottic cancer can be treated with laser resection or radiotherapy. In an earlier study, we found that voice function after laser resection was inferior to that after radiotherapy. OBJECTIVES: This study was designed to determine if reduced margins at laser resection improved voice function without impairing oncologic results. METHOD: A total of 268 patients with previously untreated T1-T2 glottic carcinoma were studied. They were primarily treated with either radiotherapy (n = 119) or laser resection (n = 149). Survival, need for additional treatment (radiotherapy and/or total layngectomi) and voice function was compared. RESULT: Median follow up time was 7 years with range 0.5-16.6. There was no difference in the overall survival (p = .065) or disease-specific survival. (p = .126). After radiotherapy 32/119 patients and after laser resection 57/149 patients had recurrence. Total rate of laryngectomy was 24% in the radiotherapy group, and 8% in the laser resection group (p = .001). Voice analysis (T1A) showed more roughness in the radiotherapy group, otherwise no difference. CONCLUSIONS: By reducing the surgical margins, we have achieved a better voice function (T1A) but more patients have needed repeated laser excisions and some have also needed supplementary radiotherapy. The risk of laryngectomy and survival were apparently not affected.

Clinical and Anatomical Variation During Assessment of Maximum Glottic Angle.

INTRODUCTION: Quantitative measurement and analysis of glottic abduction is used to assess laryngeal function and success of interventions; however, the consistency of measurement over time has not been established. This study assesses the consistency of glottic abduction measurements across visits in healthy patients and anatomic factors impacting these measurements. METHODS: Review of patients with two sequential flexible stroboscopic exams over seven months from 2019-2022. Images of maximal glottic abduction were captured and uploaded into and measured with ImageJ. Cadaver heads were used to assess the impact of visualization angles on glottic measurements with a monofilament inserted into the supraglottis of each cadaver as a point of reference. Comparisons were done with a paired T-test, T-test, or Mann-Whitney U test as appropriate. RESULTS: Fifty-nine patients and twenty-six cadaveric exams were included. Absolute change in maximum glottic abduction angle (MGAA) was 6.90° (95% CI [5.36°, 8.42°]; p < 0.05). There were no significant differences in change in MGAA by gender or age. Twenty percent of patients had a change of at least 25% in their MGAA between visits. Absolute differences in glottic angle between nasal side for cadaveric measurements was 4.77 ± 4.59° (p < 0.005)-2.22° less than the change in MGAA seen over time (p = 0.185). CONCLUSION: Maximal glottic abduction angles varied significantly between visits. Factors considered to be contributing to the differences include different viewing windows between examinations due to the position and angulation of the laryngoscope and changes in patient positioning, intra- and inter-rater variations in measurement, and patient effort. LEVEL OF EVIDENCE: N/a Laryngoscope, 134:2793-2798, 2024.

Automatic Segmentation of Membranous Glottal Gap Area with U-Net-Based Architecture.

BACKGROUND: While videostroboscopy is recognized as the most popular approach for investigating vocal fold function, evaluating the numerical values, such as the membranous glottal gap area, remains too time consuming for clinical applications. METHODS: We used a total of 2507 videostroboscopy images from 137 patients and developed five U-Net-based deep-learning image segmentation models for automatic masking of the membranous glottal gap area. To further validate the models, we used another 410 images from 41 different patients. RESULTS: During development, all five models exhibited acceptable and similar metrics. While the VGG19 U-Net had a long inference time of 1654 ms, the other four models had more practical inference times, ranging from 16 to 138 ms. During further validation, Efficient U-Net demonstrated the highest intersection over union of 0.8455, the highest Dice coefficient of 0.9163, and the lowest Hausdorff distance of 1.5626. The normalized membranous glottal gap area index was also calculated and validated. Efficient U-Net and VGG19 U-Net exhibited the lowest mean squared errors (3.5476 and 3.3842) and the lowest mean absolute errors (1.8835 and 1.8396). CONCLUSIONS: Automatic segmentation of the membranous glottal gap area can be achieved through U-net-based architecture. Considering the segmentation quality and speed, Efficient U-Net is a reasonable choice for this task, while the other four models remain valuable competitors. The models' masked area enables possible calculation of the normalized membranous glottal gap area and analysis of the glottal area waveform, revealing promising clinical applications for this model. LEVEL OF EVIDENCE: NA Laryngoscope, 134:2835-2843, 2024.

Emotional expressivity in singing. Assessing physiological and acoustic indicators of two opera singers' voice characteristics.

In an earlier study, we analyzed how audio signals obtained from three professional opera singers varied when they sang one octave wide eight-tone scales in ten different emotional colors. The results showed systematic variations in voice source and long-term-average spectrum (LTAS) parameters associated with major emotion "families". For two of the singers, subglottal pressure (PSub) also was recorded, thus allowing analysis of an additional main physiological voice control parameter, glottal resistance (defined as the ratio between PSub and glottal flow), and related to glottal adduction. In the present study, we analyze voice source and LTAS parameters derived from the audio signal and their correlation with Psub and glottal resistance. The measured parameters showed a systematic relationship with the four emotion families observed in our previous study. They also varied systematically with values of the ten emotions along the valence, power, and arousal dimensions; valence showed a significant correlation with the ratio between acoustic voice source energy and subglottal pressure, while Power varied significantly with sound level and two measures related to the spectral dominance of the lowest spectrum partial. the fundamental.

Outcome of radiotherapy for the treatment of laryngeal squamous cell carcinoma in the very elderly population.

BACKGROUND: Treatment selection for squamous cell carcinoma patients aged over 84 years is controversial. This retrospective chart review examined and compared characteristics of laryngeal squamous cell carcinoma in very elderly (over 84 years) and younger patients (approximately 65 years). The secondary objective was to further evaluate the outcome of radiotherapy as a treatment modality in this patient population. METHODS: Of all 23 very elderly patients with laryngeal squamous cell carcinoma treated with radiotherapy, with or without surgery, in the Davidoff Cancer Center, from 1992 to 2012, 19 had sufficient data for analysis, and comprised the study group. RESULTS: Median age at diagnosis was 86 years. Disease stage at diagnosis was I, II, III and IVA in 53 per cent, 21 per cent, 21 per cent and 5 per cent, respectively. Median radiotherapy dose was 60 Gy given in 25 fractions. Three patients had recurrence. No patient discontinued treatment because of toxicity. Median overall survival was 3.6 years (range, 0-10 years). CONCLUSION: Very elderly laryngeal squamous cell carcinoma patients may derive a similar survival advantage as younger counterparts. Modern radiotherapy is effective and safe for treating laryngeal squamous cell carcinoma in this study population. Further, large-scale studies are needed.

A case of antenatally undiagnosed laryngeal atresia with tracheo-esophageal fistula with airway obstruction at birth and its management.

Laryngeal atresia is a rare congenital anomaly that is usually diagnosed by antenatal ultrasound, however, if undiagnosed presents with desaturation after birth. A term neonate presented with airway obstruction after birth with multiple failed attempts at intubation and was rescued by proseal laryngeal mask airway (LMA). An esophagoscopy using an Ambuscope utilizing a modified connector assembly revealed an opening on the anterior wall of the esophagus with no esophageal atresia, leading to a diagnosis of H-type tracheo-esophageal fistula (TEF) with laryngeal atresia. The ability to ventilate the neonate via LMA with an absent glottic opening raised the possibility of TEF.

Histologic Examination of Vocal Fold Mucosal Wave and Vibration.

OBJECTIVES: Despite gross anatomic and histologic differences between human and canine vocal folds, similar wave patterns have been described yet not fully characterized. We reconstructed vocal fold (VF) vibration in a canine hemilarynx and performed histologic examination of the same vocal fold. We demonstrate comparable wave patterns while exploring the importance of certain anatomic architectures. METHODS: An in vivo canine hemilarynx was phonated against a glass prism at low and high muscle activation conditions. Vibration was captured using high-speed video, and trajectories of VF medial surface tattooed landmarks were 3D-reconstructed. The method of empirical eigenfunctions was used to capture the essential dynamics of vibratory movement. Histologic examination of the hemilarynx was performed. RESULTS: Oscillation patterns were highly similar between the in vivo canine and previous reports of ex vivo human models. The two most dominant eigenfunctions comprised over 90% of total variance of movement, representing opening/closing and convergent/divergent movement patterns, respectively. We demonstrate a vertical phase difference during the glottal cycle. The time delay between the inferior and superior VF was greater during opening than closing for both activation conditions. Histological examination of canine VF showed not only a thicker lamina propria layer superiorly but also a distinct pattern of thyroarytenoid muscle fibers and fascicles as described in human studies. CONCLUSIONS: Histologic and vibratory examination of the canine vocal fold demonstrated human vocal fold vibratory patterns despite certain microstructural differences. This study suggests that the multilayered lamina propria may not be fundamental to vibratory patterns necessary for human-like voice production. LEVEL OF EVIDENCE: NA (Basic science study) Laryngoscope, 134:264-271, 2024.