Resolving the complexity in human milk oligosaccharides using pure shift NMR methods and CASPER.

Human milk oligosaccharides belong to an important class of bioactive molecules with diverse effects on the development of infants. NMR is capable of providing vital structural information about oligosaccharides which can aid in determining structure-function relationships. However, this information is often concealed by signal overlap in 1H spectra, due to the narrow chemical shift range and signal multiplicity. Signal overlap in oligosaccharide spectra can be greatly reduced, and resolution improved, by utilising pure shift methods. Here the benefits of combining pure shift methods with the CASPER computational approach to resonance assignment in oligosaccharides are demonstrated.

Pure shift FESTA: An ultra-high resolution NMR tool for the analysis of complex fluorine-containing spin systems.

NMR measurements of molecules containing sparse fluorine atoms are becoming increasingly common due to their prevalence in medicinal chemistry. However, the presence of both homonuclear and heteronuclear scalar couplings severely complicates their analysis by NMR. In complex systems, FESTA, a heteronuclear spectral editing method, allows simplified 1 H NMR spectra to be obtained containing only 1 H signals from the same spin system as a chosen 19 F. Despite spectral simplification, signal overlap due to the presence of scalar couplings is often a problem in FESTA spectra. Here, we report a new experiment that combines FESTA and pure shift methods to provide fully decoupled ultra-high resolution FESTA spectra showing a single signal for each 1 H chemical environment. The utility of the method is demonstrated for the analysis of two complex fluorine-containing mixtures of pharmaceutical and biochemical interest.

Giving Pure Shift NMR Spectroscopy a REST─Ultrahigh-Resolution Mixture Analysis.

Most interesting problems in chemistry, biology, and pharmacy involve mixtures. However, analysis of such mixtures by NMR remains a challenge, often requiring the mixture components to be physically separated before analysis. A variety of methods have been proposed that exploit species-specific properties such as diffusion and relaxation to distinguish between the signals of different components in a mixture without the need for laborious separation. However, these methods can struggle to distinguish between components when signals overlap. Here, we exploit the relaxation properties of selected nuclei to distinguish between different components of a mixture while using pure shift methods to increase spectral resolution by up to an order of magnitude, greatly reducing signal overlap. The advantages of the new method are demonstrated in a mixture of d-xylose and l-arabinose, distinguishing unambiguously between the five major species present.

Affordable, web-based surgical skill training and evaluation tool.

Advances in the medical field have increased the need to incorporate modern techniques into surgical resident training and surgical skills learning. To facilitate this integration, one approach that has gained credibility is the incorporation of simulator based training to supplement traditional training programs. However, existing implementations of these training methods still require the constant presence of a competent surgeon to assess the surgical dexterity of the trainee, which limits the evaluation methods and relies on subjective evaluation. This research proposes an efficient, effective, and economic video-based skill assessment technique for minimally invasive surgery (MIS). It analyzes a surgeon's hand and surgical tool movements and detects features like smoothness, efficiency, and preciseness. The system is capable of providing both real time on-screen feedback and a performance score at the end of the surgery. Finally, we present a web-based tool where surgeons can securely upload MIS training videos and receive evaluation scores and an analysis of trainees' performance trends over time.

Functional Electrical Stimulation of the Feline Larynx With a Flexible Ribbon Electrode Array.

OBJECTIVES: Success of laryngeal reanimation through neurorrhaphy has been limited by synkinesis and preoperative muscle atrophy. The objective of this study was to investigate the use of epimysial electrode arrays as a means of delivering electrical stimulation to the posterior cricoarytenoid muscles in order to control laryngeal abduction. METHODS: Ribbon electrode arrays with 4 or 8 electrode contacts were used. Four cats underwent implantation of electrode arrays along the surface of the posterior cricoarytenoid muscles. The glottis was visualized with a 0° telescope while electrodes were stimulated at different amplitudes and pulse-width durations. Recordings of stimulated vocal folds were analyzed, and the degree of vocal fold abduction was measured in order to create recruitment curves for the left and right posterior cricoarytenoid. Recruitment curves from electrode channels within the array were compared. RESULTS: Electrodes oriented along the medial aspect of the posterior cricoarytenoid stimulated graded physiologic degrees of abduction depending on the amplitude of stimulation. Electrodes oriented laterally along the posterior cricoarytenoid stimulated greater degrees of simultaneous adduction with abduction. CONCLUSION: Acute studies of ribbon surface electrode arrays placed onto the posterior cricoarytenoid reproduce graded degrees of abduction necessary for the precise function of respiration and speech.

Collaborative virtual reality based advanced cardiac life support training simulator using virtual reality principles.

BACKGROUND: Advanced Cardiac Life Support (ACLS) is a series of team-based, sequential and time constrained interventions, requiring effective communication and coordination of activities that are performed by the care provider team on a patient undergoing cardiac arrest or respiratory failure. The state-of-the-art ACLS training is conducted in a face-to-face environment under expert supervision and suffers from several drawbacks including conflicting care provider schedules and high cost of training equipment. OBJECTIVE: The major objective of the study is to describe, including the design, implementation, and evaluation of a novel approach of delivering ACLS training to care providers using the proposed virtual reality simulator that can overcome the challenges and drawbacks imposed by the traditional face-to-face training method. METHODS: We compare the efficacy and performance outcomes associated with traditional ACLS training with the proposed novel approach of using a virtual reality (VR) based ACLS training simulator. One hundred and forty-eight (148) ACLS certified clinicians, translating into 26 care provider teams, were enrolled for this study. Each team was randomly assigned to one of the three treatment groups: control (traditional ACLS training), persuasive (VR ACLS training with comprehensive feedback components), or minimally persuasive (VR ACLS training with limited feedback components). The teams were tested across two different ACLS procedures that vary in the degree of task complexity: ventricular fibrillation or tachycardia (VFib/VTach) and pulseless electric activity (PEA). RESULTS: The difference in performance between control and persuasive groups was not statistically significant (P=.37 for PEA and P=.1 for VFib/VTach). However, the difference in performance between control and minimally persuasive groups was significant (P=.05 for PEA and P=.02 for VFib/VTach). The pre-post comparison of performances of the groups showed that control (P=.017 for PEA, P=.01 for VFib/VTach) and persuasive (P=.02 for PEA, P=.048 for VFib/VTach) groups improved their performances significantly, whereas minimally persuasive group did not (P=.45 for PEA, P=.46 for VFib/VTach). Results also suggest that the benefit of persuasiveness is constrained by the potentially interruptive nature of these features. CONCLUSIONS: Our results indicate that the VR-based ACLS training with proper feedback components can provide a learning experience similar to face-to-face training, and therefore could serve as a more easily accessed supplementary training tool to the traditional ACLS training. Our findings also suggest that the degree of persuasive features in VR environments have to be designed considering the interruptive nature of the feedback elements.

The Diagnosis of Granulomatosis With Polyangiitis When Serology and Biopsies are Negative.

Objective: Granulomatosis with polyangiitis (GPA) is a potentially fatal condition which often manifests in the head and neck. Currently, diagnosis relies on antineutrophil cytoplasmic autoantibody (c-ANCA) serology and mucosal or renal biopsy. However, a significant proportion of patients with GPA limited to the head and neck are seronegative and biopsy negative. This study evaluates the role of clinical diagnosis of GPA in the absence of positive laboratory findings. Study Design: Case series with chart review. Setting: Academic Tertiary Medical Center. Methods: This was a retrospective review of 143 patients treated in an outpatient otolaryngology clinic at a tertiary care hospital for known or suspected GPA from 1998 to 2021. Presenting symptoms, C-ANCA status at initial presentation, biopsy results, long-term serology results, and time to initiation of treatment were analyzed. Results: Twenty-six of 143 (18.2%) patients were seronegative; only 3 of these patients (12%) had positive biopsies. Seventeen (73.9%) of these patients presented with nasal and sinus disease and 12 (52.2%) presented with airway involvement. Only 4 (17.4%) patients had renal involvement. Delay in treatment of patients with negative laboratory workup ranged from 0 months to 11 years. All patients who were seronegative and/or biopsy negative at presentation responded clinically to immunosuppressive therapy. Conclusion: GPA cases are often limited to the upper respiratory tract, making diagnosis difficult, particularly in seronegative patients. These results suggest that, when GPA is suspected, despite negative serology, the diagnosis of GPA should be made on clinical grounds, and empiric therapy encouraged to prevent delay in treatment.

Type II Thyroplasty with Bilateral Partial Cricothyroid Myectomy for Vocal Tic in Child with Cerebral Dysgenesis.

Vocal tics can occur in neuropsychiatric disorders and result in familial distress. Management is challenging, particularly in children with developmental delay. A 5-year-old with cerebral dysgenesis presented with a high amplitude, high-frequency vocal tic. Type II thyroplasty with bilateral cricothyroid muscle myectomy was performed after initial botulinum toxin trial. Amount, volume, and pitch of tics significantly decreased, without change in swallow. Benefits persisted at 1-year follow-up. This is the first description of combined type II thyroplasty with cricothyroid myectomy for high-frequency vocal tic. This can be done safely and provide sustained benefit for a rare, impactful voice disorder.

Long-Term Outcomes and Revision Rates in Laryngeal Reinnervation.

OBJECTIVES: Nonselective laryngeal reinnervation is an effective procedure to improve voice quality after unilateral vocal fold paralysis. Few studies have captured long-term outcome data, and the revision rate for this operation is currently unknown. The objective of this study is to describe the long-term outcomes and revision rates of unilateral, nonselective reinnervation in pediatric and adult patients. METHODS: Patients who underwent laryngeal reinnervation from 2000 to 2022 with a single surgeon were identified for inclusion. Patients who underwent bilateral, super selective, deinnervation and reinnervation, and/or concurrent arytenoid adduction procedures were excluded. Outcome measures included maximum phonation time [MPT], voice handicap index score [VHI], patient-reported percent normal voice, revision procedures, and complications. Data were compiled and analyzed using paired t-tests, repeated measures analysis of covariance, and binary logistic regression analysis. RESULTS: One hundred thirty-two patients underwent unilateral, nonselective ansa-recurrent laryngeal nerve [RLN] laryngeal reinnervation. Reinnervation significantly improved MPT and patient-reported percentage of normal voice and significantly decreased VHI. Eleven patients underwent revision procedures, corresponding to a revision rate of 8.3%. Additional procedures included medialization laryngoplasty [n = 3], medialization laryngoplasty with arytenoid adduction [n = 3] and injection augmentation greater than 1 year after reinnervation [n = 5]. The only factor associated with the need for additional surgery was time lapse from nerve injury to reinnervation. The overall complication rate was 6.8%; no patient required reintubation or tracheostomy. CONCLUSION: Unilateral, nonselective laryngeal reinnervation can provide reliable improvement in vocal symptoms after recurrent laryngeal nerve injury. The revision rate after laryngeal reinnervation is favorable and comparable to framework surgery. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3187-3192, 2024.

Predominantly unilateral laryngomalacia in infants with unilateral vocal fold paralysis.

BACKGROUND: Neonatal unilateral vocal fold paralysis may arise iatrogenically, idiopathically, or in the context of an underlying neurologic disorder. Management is often supportive, focusing on diet modification to allow for safe oral feeding. We describe the clinical course of six infants with unilateral vocal fold paralysis who developed predominantly unilateral laryngomalacia ipsilateral to the affected vocal fold with associated severe respiratory symptoms and feeding difficulty. METHODS: Retrospective review of six infants with unilateral vocal fold paralysis and predominantly unilateral laryngomalacia. Charts were reviewed for etiology of vocal fold paralysis, presenting symptoms, operative details, postoperative course, and outcomes for breathing and swallowing. RESULTS: Etiology of vocal fold paralysis included cardiac surgery in four patients, intubation-related in one, and idiopathic in one. Presenting symptoms included increased work of breathing, stridor, feeding difficulty, respiratory failure requiring noninvasive respiratory support, and weak cry. All infants were on nasogastric tube feedings. Direct microlaryngoscopy with unilateral or predominantly unilateral (conservative contralateral aryepiglottic fold division) supraglottoplasty was performed. Stridor and work of breathing improved in all six patients within 1 week postoperatively. Oral feeding improved in three patients within 2 weeks. Three patients had persistent feeding impairment with improvement within one year. CONCLUSIONS: Predominantly unilateral laryngomalacia may arise in the context of unilateral vocal fold paralysis. Addressing the ipsilateral cuneiform collapse can improve breathing and feeding. This may be an under-described phenomenon and represents an additional reason to include the otolaryngologist early in the care of infants with suspected possible new unilateral vocal fold paralysis. Breathing and swallow can improve post-operatively, but feeding may remain limited by the vocal fold paralysis and any medical comorbidities. Ongoing follow-up and collaboration with speech-language pathology to optimize feeding are important.

Care of the child's voice: a pediatric otolaryngologist's perspective.

Children with voice problems are encountered by speech-language pathologists working in schools but not with sufficient frequency to yield a great experience in managing them. Their evaluation and treatment now are best handled by a team of specialists in pediatric otolaryngology and speech-language pathology with expertise in voice and resonance disorders. The voice team uses a variety of assessment tools, including perceptual, parent- and patient-based, instrumental, and imaging measures. The most important component of the diagnostic assessment is laryngoscopy in the awake child, to visualize the vocal folds while the child phonates. This review covers the pediatric otolaryngologist's approach to dysphonia in children. The common causes of dysphonia are reviewed, including vocal nodules and other lesions, reflux laryngitis, laryngeal paralysis, congenital glottic webs, laryngeal papillomatosis, functional voice disorders, and velopharyngeal incompetence. Current treatment options are continually being modified. These are discussed by highlighting recently published research.

Surgical vs interventional radiology drainage of neck abscesses in pediatric patients.

OBJECTIVE: To compare outcomes using an open surgical incision and drainage (S-ID) versus an aspiration under interventional radiology drainage (A-ID) of pediatric neck abscesses. The primary outcome measure was successful drainage requiring one intervention, and the secondary outcome measures were readmission rates and overall cost to the healthcare system. METHODS: Retrospective data collection of all pediatric patients treated at the Primary Children's Hospital for neck abscess from 2008 to 2020. Patients who did not require drainage were not included. Comparison between S-ID and A-ID was performed according to the primary and secondary outcomes. RESULTS: Two hundred fifty nine patients were included in the study. Twenty-six patients had A-IR and 234 patients had S-ID. Patient demographics were not significantly different between both groups. Overall length of stay was greater in the A-ID group (5 vs 3.3 days) (p < 0.05). A second procedure was more frequent in the A-ID group with 11/26 (42%) versus 12/234(5%) in the S-ID group (P = 0.001) even after controlling for multiple possible confounding factors. The rate of readmission was also higher in the A-ID group with 3/26 (11%) versus 7/234 (3%) in the S-ID group (P = 0.006). Both groups showed similar overall cost (P = 0.621). CONCLUSIONS: A-ID and S-ID are both methods to treat head and neck abscess requiring drainage. However, overall results indicate a higher rate of failure requiring a second intervention and a higher rate of readmission in the A-ID group. In our study cost was noted to be similar between both methods.

Long-term Outcomes of Vocal Fold Paralysis Following Patent Ductus Arteriosus Ligation in Neonates.

INTRODUCTION: In patients undergoing patent ductus arteriosus (PDA) ligation there is a significant risk of left vocal fold paralysis (LVFP) particularly in premature neonates who are small for gestational age. The objective of this study is to determine the incidence of LVFP in infants following PDA ligation and report on long-term outcomes in patients with LVFP. METHODS: We performed a prospective study of patients undergoing PDA ligation in the newborn intensive care unit (NICU) between April 2004 and May 2014. Following PDA ligation, flexible laryngoscopy was performed to assess vocal fold mobility. Patients were then followed longitudinally to determine long-term outcomes. RESULTS: A total of 163 infants underwent PDA ligation. Thirty-six patients (22%) developed LVFP following the procedure. Twenty-five percent of neonates <1500 g experienced LVFP versus 5% of patients >1500 g (p = 0.033). Patients with LVFP were more likely to require a feeding tube (64% vs. 19.6%; p < 0.05) and spent more time in the NICU (135 days vs. 106 days; p < 0.05). Twenty-four patients received long-term follow-up. Six (25%) had complete resolution of LVFP, 10 (42%) were compensated, and 8 (33%) demonstrated persistent LVFP with no improvement. CONCLUSIONS: The incidence of LVFP after PDA ligation is high especially in extremely low birth weight children. The majority of patients recovered well with time, but further surgical intervention was required in uncompensated cases. Long-term follow-up of these patients is needed to ensure improvement. Laryngoscope, 133:1257-1261, 2023.

Lighting up spin systems: enhancing characteristic 1H signal patterns of fluorinated molecules.

Fluorine is becoming increasingly prevalent in medicinal chemistry, both in drug molecules and in molecular probes. The presence of fluorine allows convenient monitoring of such molecules in complex environments by NMR spectroscopy. However, sensitivity is a persistent limitation of NMR, especially when molecules are present at low concentrations. Here, sensitivity issues with 1H NMR are mitigated by sharing 19F photochemically-induced dynamic nuclear polarisation with 1H nuclei. Unlike direct 1H enhancement, this method enhances 1H signals without significantly distorting multiplet intensities, and has the potential to enable the use of suitable molecules as low-concentration probes.

Optimization of Subglottic View During Flexible Laryngoscopy With Patient Positioning.

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

Ultra-selective, ultra-clean 1D rotating-frame Overhauser effect spectroscopy.

An ultra-selective 1D NMR experiment - GEMSTONE-ROESY - enables clear, unambiguous assignment of ROE signals in the not uncommon situation that traditional selective methods fail. Its usefulness is demonstrated in the analysis of the natural products cyclosporin and lacto-N-difucohexaose I, providing detailed insight into the structures and conformations of these molecules.

Multi-Institutional Study of Patient-Reported Outcomes of Paradoxical Vocal Fold Motion.

OBJECTIVE: To explore patient-reported outcome measures of pediatric paradoxical vocal fold motion through a multi-institutional study of geographically diverse United States medical facilities to assess long-term management and outcomes. METHODS: Eligible participants >8 years of age diagnosed with PVFM over a 10-year period from 7 tertiary pediatric hospitals were invited to complete a survey addressing study objectives. RESULTS: 65 participants completed the survey, of whom 80% were female, 75% reported a 3.5 grade point average or better, and 75% identified as competitive athletes or extremely athletic individuals. Participants rated their perceived efficacy of 13 specific treatments. Only five treatments were considered effective by a majority of the participants who tried them. The treatments that participants tried most often were breathing exercises (89.2%), bronchodilator treatments (45%), and allergy medications (35.4%). 78.8% of participants reported receiving more than one treatment and 25% reported receiving a combination of bronchodilators, anticholinergics, and steroids. At the time of PVFM diagnosis, 38% of participants had no idea when their symptoms would completely resolve. 23.3% of participants did not experience symptom resolution until greater than 1 year after diagnosis. CONCLUSIONS: Traditional management tools such as breathing exercises and biofeedback treatments may not provide the long-term benefit that providers anticipate. In addition to these commonly used management strategies, highly efficacious techniques such as counseling and lifestyle management should be incorporated into the long-term management of patients whose symptoms are refractory to traditional care. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:970-976, 2023.

Using Nurse-Driven Protocols to Eliminate Routine Gastric Residual Volume Measurements: A Retrospective Study.

BACKGROUND: Multiple critical care guidelines support the elimination of routine gastric residual volume monitoring in patients receiving enteral nutrition. However, transitioning nursing practice away from routine gastric residual volume assessments has proved challenging. OBJECTIVE: To evaluate outcomes after the elimination of routine gastric residual volume monitoring in a 14-bed adult intensive care unit at a large teaching hospital in the southeastern United States. METHODS: Practice change was accomplished through in-service training and implementation of a validated protocol. Data were collected for 30 days before and 30 days after protocol implementation to determine effects on the total volume of enteral nutrition received as well as the rate of adverse events after elimination of routine gastric residual volume assessments (n = 22) as compared with previous standard practice (n = 25). RESULTS: When gastric residual volume was not measured, the mean (SD) percentage of enteral nutrition delivery was 81% (12%) of the ordered volume, compared with 60% (18%) in the historic control group (P = .002). Eliminating gastric residual volume monitoring was not associated with an increased rate of adverse events (emesis, aspiration pneumonia) or a change in length of stay. Nursing staff demonstrated a high degree of compliance with this protocol change. CONCLUSION: The findings of this study indicate that the elimination of routine gastric residual volume assessment does not increase the rate of adverse events and results in increased nutrition provision. Use of a protocol for practice change as well as mandatory in-service training may effect changes in nursing practice.

Emotional Adjustment in Children with Vocal Fold Nodules.

INTRODUCTION: Vocal fold nodules (VNs) in children are benign, bilateral, callous-like lesions at the junction of the anterior third and posterior two-thirds of the true vocal folds. Chronic, repetitive, and intense vocal behavior is often cited as the primary etiology; however, difficulties with emotional adjustment may predispose some children towards extreme and possibly phonotraumatic vocal activity, thereby contributing secondarily to the development of VNs. OBJECTIVES: This case-control study examined the association between features of emotional adjustment and VNs in children. METHODS: Parents of children with VNs (N = 40, Mage = 7.5, SDage = 2.03) and two medical control groups [ie, voice disordered, but not VNs (VDCs; N = 40, Mage= 7.09, SDage = 2.01) and vocally normal controls (VNCs; N = 40, Mage = 7.6, SDage = 1.54)] participated in the study. Features of emotional adjustment were assessed using two inventories: the Parent Rating scale for Reactive and Proactive Aggression and the Revised Child Anxiety and Depression Scale - Parent version. RESULTS: As compared with the VNCs, children with VNs were significantly more aggressive (P = 0.042, Cohen's d = 0.47) whereas the VDCs were more depressed (P = 0.013, Cohen's d = 0.60). Furthermore, VDCs experienced more separation anxiety than VNs (P = 0.038, Cohen's d = 0.45) and VNCs (P = 0.021, Cohen's d = 0.55). No other significant between-group differences were identified between the VNs and VDCs. CONCLUSIONS: When present, elevated aggression may represent a risk factor for VNs formation in children, and possibly influence treatment outcomes. Therefore, the current results highlight the importance of understanding the role of emotional adjustment in the evaluation and treatment of dysphonia in children.

"I've never been able to burp": Preliminary description of retrograde cricopharyngeal dysfunction in children.

OBJECTIVE: Retrograde cricopharyngeal dysfunction was recently described by Bastian in 2019 and is characterized by an inability to belch, abdominal or chest pressure, odd gurgling noises, and occasional difficulty vomiting. Symptoms tend to worsen with carbonated beverages. Currently, the recommended treatment is cricopharyngeus muscle botulinum toxin injections. Prior studies have included few pediatric patients within larger datasets comprised primarily of adults. We describe our preliminary experience in pediatric patients, including presenting symptoms, treatment approach, and post-treatment outcomes. METHODS: Retrospective chart review of pediatric patients (aged <18 years) diagnosed with retrograde cricopharyngeal dysfunction based on clinical history by the senior author. Medical records were reviewed for presenting symptoms, prior testing and treatment, details of treatment, and postoperative outcomes. RESULTS: Five patients with average age of 14 ± 4 (3 females, 2 males) were included. Presenting symptoms included lifelong or nearly lifelong inability to burp (n = 5), bloating (n = 5), awkward gurgling noises (n = 3), and worsening of symptoms with carbonated beverages (n = 5). Two patients had prior normal upper endoscopy. All patients underwent cricopharyngeal botulinum toxin injection under general anesthesia, with 25-50 units of botulinum toxin injected to the posterior cricopharyngeus across 4-5 locations. All patients had resolution of symptoms with follow-up of 1.5-10 months. CONCLUSIONS: Retrograde cricopharyngeal dysfunction may be underdiagnosed due to lack of awareness of the condition. Now that the phenomenon of inability to belch has a name and is being reported in the literature, we will likely see more adult and pediatric patients with these symptoms. Pediatric patients may respond similarly to adults. Larger studies with longer-term follow-up and targeted patient-reported outcome measures are needed to characterize disease presentation and treatment outcomes.