Measurement Reliability of Laryngeal Resistance and Mean Flow Rate in Pediatric Subjects.

OBJECTIVE: Mean flow rate (MFR) and laryngeal resistance (RL) are sensitive to changes in glottal configuration and biomechanics. There is little reported on aerodynamic parameters in children. We conducted a pilot study to evaluate MFR and RL measurement reliability in a pediatric population using labial and mechanical interruption methods. METHOD: Thirty-nine subjects aged 4-17 performed 10 trials per method. For labial interruptions, subjects produced five labial plosives at a comfortable amplitude. For mechanical interruptions, subjects maintained a steady /α/ while a balloon valve interrupted their airflow five times for 250 milliseconds each. MFR was measured as the flow through the interruption device between interruptions. RL was calculated by dividing subglottal pressure (Ps) by MFR. The primary outcome measures of this study were the coefficients of variation of MFR and RL. Paired t tests were used to compare each variable between the two methods. Pearson's correlation was used to analyze the relationship between each parameter and subject age. RESULTS: Mean PS (t(38) = 2.966, P < 0.01) and RL (t(38)=3.563, P < 0.01) were higher for labial interruptions while mean MFR (t(38) = -2.036, P < 0.05) was lower. Intrasubject coefficients of variation were higher for the labial technique for both MFR (t(38) = 4.939, P < 0.001) and RL (t(38) = 3.439, P < 0.01) while there was no difference in PS variability (P = 0.260). Mean MFR and RL were related to age for both the labial (MFR: r = 0.588, P < 0.001; RL: r = -0.468, p = 0.003) and mechanical trials (MFR: r = 0.534, P < 0.001; RL: r = -0.496, P = 0.001). The coefficients of variation for RL were negatively correlated with age for both labial (r = -0.415, P = 0.009) and mechanical trials (r = -0.471, P = 0.002). MFR was only correlated in the labial trials (r = -0.514, P = 0.001) and PS was only correlated in the mechanical trials (r = -0.519, P = 0.001). CONCLUSIONS: Differences in means and intrasubject variation are likely due to differences in task and measurement timing. Precision of MFR and RL measurement in pediatric subjects was higher for mechanical interruption; further exploration of this method and its clinical utility is warranted. Measurement of aerodynamic parameters may be a useful addition to pediatric voice assessment.

Measurement reliability of phonation threshold pressure in pediatric subjects.

OBJECTIVES/HYPOTHESIS: Phonation threshold pressure (PTP), the minimum subglottal pressure (Ps ) required for phonation, is sensitive to changes in laryngeal biomechanics and is often elevated with pathology. Little is reported on PTP in children; challenges with task performance and measurement reliability represent barriers to routine clinical assessment. STUDY DESIGN: Pilot study evaluating PTP and Ps measurement reliability in children using labial and mechanical interruption. METHODS: Twenty-two subjects aged 4 to 17 years (10.7 ± 3.9 years) participated. Ten trials were performed for each method; task order was randomized. For labial interruption, subjects produced /pα/ five times at softest (onset PTP) and comfortable amplitude. For mechanical interruption, subjects produced a sustained /α/ while a balloon valve interrupted phonation five times for 250 ms each; mechanical interruption was performed with a mouthpiece and mask. PTP was recorded as the difference between Ps and supraglottal pressure at phonation cessation (offset PTP). Mean PTP and Ps and intrasubject coefficients of variation were compared. Correlations with age were evaluated. RESULTS: Mean PTP (P < .001) and Ps (P = .005) were higher for labial interruption. Intrasubject coefficients of variation for PTP (P = .554) and Ps (P = .305) were similar across methods. Coefficient of variation was related to age for mechanical-mask trials only (r = -0.628, P = .00175). CONCLUSIONS: Differences in means are likely related to differences in task and PTP hysteresis effect. Reliability is comparable with all methods; using a mouthpiece may be preferable to a mask for mechanical interruption. Measurement of PTP is noninvasive, reliable, and may be a useful adjunct in pediatric voice assessment. LEVEL OF EVIDENCE: 3b Laryngoscope, 129:1520-1526, 2019.

A Preliminary Case Report of a High-Quality Cost-effective Rigid Laryngoscopy Setup.

OBJECTIVE: To evaluate a cost-effective modified rigid laryngoscopy setup with a portable light source and high-resolution commercially available digital camera for use in smaller otolaryngology and family practice clinics. METHODS: The modified setup was used to obtain images of the larynx using both a traditional light source and a portable light source. Varying shutter speeds and ISOs were evaluated, and the optimal settings were determined for the modified setup. RESULTS: Picture quality was adequate, and the portable light source was bright enough. ISO from 640 to 1600 with shutter speeds ranging from 1/60 to 1/160 are ideal under the normal light source, while it is better to set the ISO between 4000 and 10 000 with shutter speeds from 1/60 to 1/100 under the portable light source. Picture quality was adequate with a resolution of 2768 pixels × 1848 pixels with 350 dpi × 350 dpi. CONCLUSIONS: Results show that the modified setup obtains images of adequate quality for use in the clinic. Additionally, since the larynx requires the most illumination for endoscopic imaging, a similar setup would work for imaging the ear and nose. This setup may make laryngoscopic exams more accessible to patients at smaller laryngoscopy clinics or family practice providers.

Simulation of KTP Laser-Based Zenker Diverticulotomy with a Porcine Model and Laryngeal Dissection Station.

Zenker's diverticulum is a rare cause of progressive dysphagia that is treated surgically. KTP laser-based diverticulotomy is one effective treatment. Developing a simulation model is helpful for rare conditions. Pigs have a natural hypopharyngeal pouch similar to a diverticulum. We present a model for performing rigid endoscopic KTP laser diverticulotomy in a porcine model using a laryngeal dissection station. Eleven pigs were examined to confirm presence of the hypopharyngeal pouch. A specimen was mounted on the modified laryngeal dissection station and a KTP laser-based diverticulotomy was performed. Novel aspects include use of the laryngeal dissection station and application of the model for simulating rigid endoscopic KTP laser diverticulotomy. This model allows trainees to practice equipment setup, positioning of the laryngoscope to isolate the cricopharyngeal bar, tissue handling, laser safety techniques, and use of the KTP laser through the laryngoscope under microscopic visualization.

Neonatal Repair in a Patient With Heterotaxy, Truncus Arteriosus, Pulmonary Artery Sling, and Tracheal Stenosis.

We present a newborn with heterotaxy features, multiple congenital anomalies, truncus arteriosus with long segment tracheal stenosis, and a left pulmonary artery sling. The patient had complete neonatal repair with slide tracheoplasty and repair of the left pulmonary artery sling with anterior translocation of the pulmonary artery. The truncus was repaired with a transventricular ventricular septal defect closure with a patch and right ventricle to pulmonary artery conduit. Complete repair of complex cardiac neonatal lesions with critical tracheal stenosis is feasible and should be the strategy of choice in these complex patients.

Care of pediatric tracheostomy in the immediate postoperative period and timing of first tube change.

OBJECTIVE: To analyze the safety of a standardized pediatric tracheostomy care protocol in the immediate postoperative period and its impact on tracheostomy related complications. STUDY DESIGN: Retrospective case series. SUBJECTS: Pediatric patients undergoing tracheotomy from February 2010-February 2014. METHODS: In 2012, a standardized protocol was established regarding postoperative pediatric tracheostomy care. This protocol included securing newly placed tracheostomy tubes using a foam strap with hook and loop fastener rather than twill ties, placing a fresh drain sponge around the tracheostomy tube daily, and performing the first tracheostomy tube change on postoperative day 3 or 4. Outcome measures included rate of skin breakdown and presence of a mature stoma allowing for a safe first tracheostomy tube change. Two types of tracheotomy were performed based on patient age: standard pediatric tracheotomy and adult-style tracheotomy with a Bjork flap. Patients were analyzed separately based on age and the type of tracheotomy performed. RESULTS: Thirty-seven patients in the pre-protocol group and 35 in the post-protocol group were analyzed. The rate of skin breakdown was significantly lower in the post-protocol group (standard: p=0.0048; Bjork flap: p=0.0003). In the post-protocol group, all tube changes were safely accomplished on postoperative day three or four, and the stomas were deemed to be adequately matured to do so in all cases. CONCLUSION: A standardized postoperative pediatric tracheostomy care protocol resulted in decreased rates of skin breakdown and demonstrated that pediatric tracheostomy tubes can be safely changed as early as 3 days postoperatively.

Current use of intralesional cidofovir for recurrent respiratory papillomatosis.

OBJECTIVES/HYPOTHESIS: The authors sought to define the indications, administration, and adverse events associated with intralesional cidofovir use for recurrent respiratory papillomatosis (RRP). STUDY DESIGN: Cross-sectional study. METHODS: A 21-question online survey was distributed to 115 selected adult and pediatric laryngeal surgeons internationally. Results were used to draft statements of best practice, which were approved by the full membership of the RRP Task Force. RESULTS: Eighty-two surgeons, who altogether presently manage 3,043 patients with RRP, responded to the survey. Seventy-four surgeons previously used cidofovir, reporting 1,248 patients in the last decade (estimated 801 adults and 447 children). Single indications for adjuvant cidofovir included six or more surgeries per year, increasing frequency of surgery, and extralaryngeal spread (in children). Most adult surgeons use 20 to 40 mg in <4 mL; pediatric surgeons use <20 mg in <2 mL. Scheduled administration following an initiation trial of five injections is common; cidofovir is discontinued following a complete response. Most surgeons biopsy routinely, use special informed consent, and are willing to participate in multi-institutional clinical trials on cidofovir uses, efficacy, and safety. CONCLUSIONS: Eighteen statements were approved by the RRP Task Force after discussion of the survey results. Intralesional cidofovir may be initiated if surgical debulking is required every 2 to 3 months. The concept of an adjuvant regimen with regular biopsy is favored. Administration should remain below established safe limits of dosing (3 mg/kg) and volume. Informed consent, including discussion of off-label use and acute kidney injury in children, is important. A special consent form sample is included. There remains a need for high-quality data.

Endoscopic changes in the upper airway after mandibular distraction osteogenesis.

INTRODUCTION: Children with micrognathia secondary to craniofacial disorders can experience significant airway and feeding difficulties. Mandibular distraction osteogenesis (MDO) is one treatment of severe micrognathia. We examined endoscopic images for upper airway (UA) soft tissue changes after MDO. We hypothesized that MDO produces consistent changes in UA soft tissue, which correlate with symptom resolution. MATERIALS AND METHODS: This retrospective chart review included 16 patients undergoing MDO from 2002 to 2007. Demographic data, symptom information, and preoperative and early and late postoperative endoscopic images were collected. Blinded randomized images of UA soft tissues were quantitatively analyzed using ImageJ. To compare nonstandardized images, ratios of UA dimensions were made. Preoperative and early and late postoperative ratios were statistically analyzed with Student's t-test. RESULTS: Sixteen patients with a mean age of 237 days were included. Mean distance distracted was 12 mm. There were significant changes in relative dimensions of the supraglottic space in the early postoperative period, which were not maintained in the late postoperative period. Nevertheless, all experienced complete relief of airway obstruction. DISCUSSION: Our study showed a significant increase in supraglottic space dimensions after MDO that was not maintained over time. This is likely because of the limitation of images and measurement methods. Despite this, significant clinical improvement was seen in all patients, with resolution of airway obstruction. This suggests supraglottic changes as well as tongue base alterations are related to clinical improvement. Further investigation of alterations in UA after MDO is needed to continue characterizing these changes.

Implementation of a program for surgical education in laryngology.

OBJECTIVES: To describe the implementation of a program for surgical education in laryngology. METHODS: Items necessary to modify a temporal bone lab for laryngeal dissection purposes were identified, and costs to do so were calculated. The prices and availability of human and canine laryngeal specimens to be used for teaching purposes were then compared. Endoscopic and open laryngeal surgery were performed on canine larynges to determine suitability as a teaching model. A laryngeal dissection course with teaching objectives was created and instituted in an Otolaryngology-Head and Neck Surgery residency training program. RESULTS: Modifications to convert an existing temporal bone lab into a laryngeal dissection lab cost $7,425. Canine larynges were found to strongly resemble human larynges and were easily used in a teaching model. They were more easily acquired and less expensive than human larynges. A novel dissection approach was created to maximize utility of a single cadaveric laryngeal specimen. Development of a laryngeal dissection manual facilitated a laryngeal dissection course. CONCLUSIONS: A laryngeal dissection educational course can be instituted with simple and relatively inexpensive modifications to an existing temporal bone laboratory. Canine larynges can be substituted for human larynges for a substantial cost savings without educational compromise. The educational methods demonstrated can be easily duplicated at other training sites.

Clinical practice guideline: hoarseness (dysphonia).

OBJECTIVE: This guideline provides evidence-based recommendations on managing hoarseness (dysphonia), defined as a disorder characterized by altered vocal quality, pitch, loudness, or vocal effort that impairs communication or reduces voice-related quality of life (QOL). Hoarseness affects nearly one-third of the population at some point in their lives. This guideline applies to all age groups evaluated in a setting where hoarseness would be identified or managed. It is intended for all clinicians who are likely to diagnose and manage patients with hoarseness. PURPOSE: The primary purpose of this guideline is to improve diagnostic accuracy for hoarseness (dysphonia), reduce inappropriate antibiotic use, reduce inappropriate steroid use, reduce inappropriate use of anti-reflux medications, reduce inappropriate use of radiographic imaging, and promote appropriate use of laryngoscopy, voice therapy, and surgery. In creating this guideline the American Academy of Otolaryngology-Head and Neck Surgery Foundation selected a panel representing the fields of neurology, speech-language pathology, professional voice teaching, family medicine, pulmonology, geriatric medicine, nursing, internal medicine, otolaryngology-head and neck surgery, pediatrics, and consumers. RESULTS: The panel made strong recommendations that 1) the clinician should not routinely prescribe antibiotics to treat hoarseness and 2) the clinician should advocate voice therapy for patients diagnosed with hoarseness that reduces voice-related QOL. The panel made recommendations that 1) the clinician should diagnose hoarseness (dysphonia) in a patient with altered voice quality, pitch, loudness, or vocal effort that impairs communication or reduces voice-related QOL; 2) the clinician should assess the patient with hoarseness by history and/or physical examination for factors that modify management, such as one or more of the following: recent surgical procedures involving the neck or affecting the recurrent laryngeal nerve, recent endotracheal intubation, radiation treatment to the neck, a history of tobacco abuse, and occupation as a singer or vocal performer; 3) the clinician should visualize the patient's larynx, or refer the patient to a clinician who can visualize the larynx, when hoarseness fails to resolve by a maximum of three months after onset, or irrespective of duration if a serious underlying cause is suspected; 4) the clinician should not obtain computed tomography or magnetic resonance imaging of the patient with a primary complaint of hoarseness prior to visualizing the larynx; 5) the clinician should not prescribe anti-reflux medications for patients with hoarseness without signs or symptoms of gastroesophageal reflux disease; 6) the clinician should not routinely prescribe oral corticosteroids to treat hoarseness; 7) the clinician should visualize the larynx before prescribing voice therapy and document/communicate the results to the speech-language pathologist; and 8) the clinician should prescribe, or refer the patient to a clinician who can prescribe, botulinum toxin injections for the treatment of hoarseness caused by adductor spasmodic dysphonia. The panel offered as options that 1) the clinician may perform laryngoscopy at any time in a patient with hoarseness, or may refer the patient to a clinician who can visualize the larynx; 2) the clinician may prescribe anti-reflux medication for patients with hoarseness and signs of chronic laryngitis; and 3) the clinician may educate/counsel patients with hoarseness about control/preventive measures. DISCLAIMER: This clinical practice guideline is not intended as a sole source of guidance in managing hoarseness (dysphonia). Rather, it is designed to assist clinicians by providing an evidence-based framework for decision-making strategies. The guideline is not intended to replace clinical judgment or establish a protocol for all individuals with this condition, and may not provide the only appropriate approach to diagnosing and managing this problem.

Describing pediatric dysphonia with nonlinear dynamic parameters.

OBJECTIVE: Nonlinear dynamic analysis has emerged as a reliable and objective tool for assessing voice disorders. However, it has only been tested on adult populations. In the present study, nonlinear dynamic analysis was applied to normal and dysphonic pediatric populations with the goal of collecting normative data. Jitter analysis was also applied in order to compare nonlinear dynamic and perturbation measures. This study's findings will be useful in creating standards for the use of nonlinear dynamic analysis as a tool to describe dysphonia in the pediatric population. METHODS: The study included 38 pediatric subjects (23 children with dysphonia and 15 without). Recordings of sustained vowels were obtained from each subject and underwent nonlinear dynamic analysis and percent jitter analysis. The resulting correlation dimension (D2) and percent jitter values were compared across the two groups using t-tests set at a significance level of p=0.05. RESULTS: It was shown that D2 values covary with the presence of pathology in children. D2 values were significantly higher in dysphonic children than in normal children (p=0.002). Standard deviations indicated a higher level of variation in normal children's D2 values than in dysphonic children's D2 values. Jitter analysis showed markedly higher percent jitter in dysphonic children than in normal children (p=0.025) and large standard deviations for both groups. CONCLUSION: This study indicates that nonlinear dynamic analysis could be a viable tool for the detection and assessment of dysphonia in children. Further investigations and more normative data are needed to create standards for using nonlinear dynamic parameters for the clinical evaluation of pediatric dysphonia.

Cidofovir efficacy in recurrent respiratory papillomatosis: a randomized, double-blind, placebo-controlled study.

OBJECTIVES: We performed a prospective, double-blind, placebo-controlled, longitudinal adjuvant therapy trial to determine the efficacy of cidofovir in the treatment of severe recurrent respiratory papillomatosis (RRP). Although results of case series suggest that cidofovir may decrease the frequency and rapidity of papilloma regrowth, no blinded placebo-controlled studies have demonstrated efficacy. METHODS: Adults and children (n = 19) with aggressive RRP received either active drug (cidofovir) or placebo. When surgical intervention was needed, drug or placebo was injected into affected areas after surgical removal of disease. The following measures were made at baseline and at 2-month intervals for the course of 12 months: Derkay papilloma severity grading scale, Voice Handicap Index, Health-Related Quality of Life, and total number of procedures performed over 12 months. RESULTS: At 2- and 12-month follow-ups, there was a significant (p < .05) improvement in the Derkay Severity Score within the cidofovir and placebo groups, but no difference between groups, and no difference between groups in the number of procedures performed. Significant improvement was found in Voice Handicap Index scores in the cidofovir group at the 12-month follow-up. No differences were seen in Health-Related Quality of Life. CONCLUSIONS: A randomized, blinded, placebo-controlled trial is necessary in the study of RRP, because the natural history of the disease can include remissions and reactivations. We found a significant improvement in the Derkay Severity Score 12 months after the baseline assessment in patients treated with cidofovir. This effect, however, was also seen in the placebo group. Accordingly, we were unable to provide proof of efficacy of cidofovir in the treatment of RRP.

Disorders of phonation in children.

Vocal disturbances in children are surprisingly common. Typical pathologic conditions differ, however, from those that are seen commonly in adults. Disturbances in the vibratory characteristic of the vocal folds cause dysphonia. The most common causes for dysphonia are infectious, anatomic, congenital, inflammatory, neoplastic, neurologic, or iatrogenic in nature. A child who presents with hoarseness demands a rapid and thorough assessment. Fine points during the history may provide the clinician with clues as to the correct etiologic category. Proper treatment requires an accurate diagnosis. Although some conditions are similar in the adult larynx, treatment of the pediatric larynx often differs. An understanding of the changing and growing pediatric larynx is necessary for treatment and satisfactory results.

Otolaryngic Manifestations in Children Presenting with Apparent Life-Threatening Events.

Apparent life-threatening event (ALTE) is a term used to characterize an event of unknown cause after an infant is found limp, cyanotic, bradycardic, and/or requiring resuscitation. Like sudden infant death syndrome (SIDS), ALTE is a general term used until a precise diagnosis can be established. The relationship between ALTE and SIDS has not been clearly defined, although 7 to 15 percent of children with ALTE die of SIDS. If children with ALTE are at greater risk for SIDS, morbidity and mortality may be prevented if the underlying pathology can be identified and corrected or closely monitored. The otolaryngologist is being consulted more frequently to evaluate children who have been through an ALTE to help elucidate any underlying pathology that may have caused the near-death experience. This retrospective chart review reports the evaluation of 30 infants with ALTE requiring consultation by the Division of Pediatric Otolaryngology at the Children's Memorial Hospital in Chicago during a 3-year period. We reviewed the literature and here compare our findings with current animal models. Of the 30 children evaluated, 53% had gastroesophageal reflux, 40% had laryngeal abnormalities, 13% had tracheal abnormalities, and 10% had pharyngeal abnormalities. Thirteen percent of the children had nonotolaryngic anomalies identified during evaluation. Surgical intervention was required in 10 patients and medical treatment was used in 18. When evaluating a child with ALTE, a complete history and physical examination, evaluation for gastroesophageal reflux, assessment for upper airway obstruction by radiographs and endoscopy, and a multidisciplinary approach are recommended. (Otolaryngol Head Neck Surg 1997;116:575-9.).