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Shot peening is a surface treatment process that improves the fatigue life of a material and suppresses cracks by generating residual stress on the surface. The injected small shots create a compressive residual stress layer on the material's surface. Maximum compressive residual stress occurs at a certain depth, and tensile residual stress gradually occurs as the depth increases. This process is primarily used for nickel-based superalloy steel materials in certain environments, such as the aerospace industry and nuclear power fields. To prevent such a severe accident due to the high-temperature and high-pressure environment, evaluating the residual stress of shot-peened materials is essential in evaluating the soundness of the material. Representative methods for evaluating residual stress include perforation strain gauge analysis, X-ray diffraction (XRD), and ultrasonic testing. Among them, ultrasonic testing is a representative, non-destructive evaluation method, and residual stress can be estimated using a Rayleigh wave. Therefore, in this study, the maximum compressive residual stress value of the peened Inconel 718 specimen was predicted using a prediction convolutional neural network (CNN) based on the relationship between Rayleigh wave dispersion and stress distribution on the specimen. By analyzing the residual stress distribution in the depth direction generated in the model from various studies in the literature, 173 residual stress distributions were generated using the Gaussian function and factorial design approach. The distribution generated using the relationship was converted into 173 Rayleigh wave dispersion data to be used as a database for the CNN model. The CNN model was learned through this database, and performance was verified using validation data. The adopted Rayleigh wave dispersion and convolutional neural network procedures demonstrate the ability to predict the maximum compressive residual stress in the peened specimen.

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Shot peening is a process wherein the surface of a material is impacted by small, spherical metal shots at high velocity to create residual stresses. Nickel-based superalloy is a material with high strength and hardness along with excellent corrosion and fatigue resistance, and it is therefore used in nuclear power plants and aerospace applications. The application of shot peening to INCONEL, a nickel-based superalloy, has been actively researched, and the measurement of residual stresses has been studied as well. Previous studies have used methods such as perforation strain gauge analysis and X-ray diffraction (XRD) to measure residual stress, which can be evaluated with high accuracy, but doing so damages the specimen and involves critical risks to operator safety due to radiation. On the other hand, ultrasonic testing (UT), which utilizes ultrasonic wave, has the advantage of relatively low unit cost and short test time. One UT method, minimum reflection measurement, uses Rayleigh waves to evaluate the properties of material surfaces. Therefore, the present study utilized ultrasonic minimum reflectivity measurements to evaluate the residual stresses in INCONEL specimens. Specifically, this study utilized ultrasonic minimum reflection measurements to evaluate the residual stress in INCONEL 718 specimens. Moreover, an estimation equation was assumed using exponential functions to estimate the residual stress with depth using the obtained data, and an optimization problem was solved to determine it. Finally, to evaluate the estimated residual stress graph, the residual stress of the specimen was measured and compared using the XRD method.

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OBJECTIVE: To characterize the evolution of swallowing and voice in patients with X-linked dystonia parkinsonism (XDP). STUDY DESIGN: Retrospective case series. METHODS: Retrospective review of 59 patients with XDP from January 2016 to January 2018. All patients underwent complete examinations and quality of life (QOL) surveys (Swallowing Quality of Life questionnaire [SWAL-QOL], Voice-Related Quality of Life [V-RQOL], and Voice Handicap Index [VHI]), and functional endoscopic examination of swallowing. We excluded patients with incomplete records or patients lost to follow-up. Univariate analysis was used to compare 2016 to 2018 Penetration-Aspiration Scale (PAS), SWAL-QOL, V-RQOL, and VHI scores. RESULTS: Ten patients met the inclusion criteria. Nine patients had oromandibular dystonia. Voice-related measures significantly worsened with an increase in mean VHI from 81 to 109.9 (P = 0.026) and decrease in mean V-RQOL from 58 to 28 (P = 0.013). Vocal strain also significantly worsened 0.4 to 1.4 (P = 0.001). Mean PAS scores increased from 4.2 to 5.1 (P = 0.068) and mean SWAL-QOL decreased from 50.4 to 43.5 (P = 0.157). In the SWAL-QOL, the mean Eating Duration score worsened from 0.9 to 0.4 (P = 0.052) and Mental Health score declined from 10.1 to 6.1 (P = 0.077). CONCLUSIONS: Both vocal strain and voice-related QOL measures considerably worsened over the 2-year interval in our limited group of XDP patients with no significant change in PAS scores or swallowing QOL. The findings demonstrated that the pace of disease affecting voice symptoms was different from swallowing symptoms in our study group and that changes in communication ability may be a more sensitive marker for disease progression than swallowing dysfunction.

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The CLP (containment liner plate) of a nuclear power plant protects the internal system from the external environment and sudden changes in internal pressure or temperature, and it is a structure that blocks and protects radioactive materials leaking inside and outside in the event of a nuclear accident and is composed of a liner plate, reinforcing bars, tendons, and concrete. Recently, corrosion on the rear side of the liner plate and concrete voids has emerged as a severe defect in nuclear power plants across South Korea. Therefore, in this study, we proposed a new inspection method that a line-type inspection method applied phased array ultrasonic testing and the area inspection method applied acoustic resonance method using developed moveable tapper. The acoustic signals were signal-processed and reproduced to a mapping image following the inspection area, and with the image, it was possible to determine the type of defect. Furthermore, an automated inspection system for within the CLP was proposed.

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OBJECTIVE: To determine the laryngoscopic findings most predictive of laterality in vocal fold paresis in patients with known RLN and/or SLN paresis by laryngeal electromyography (LEMG). STUDY DESIGN: Blinded, prospective video perceptual analysis study. METHODS: Patients with vocal fold paresis diagnosed by LEMG at a tertiary care hospital from 2017 to 2019 were identified. Two fellowship-trained laryngologists blinded to clinical history and LEMG results reviewed laryngostroboscopic examinations and assessed for evidence of paresis using defined criteria. Inclusion criteria were adults with laryngeal asymmetry and evidence of decreased recruitment on LEMG. Exclusion criteria were children, presence of laryngeal lesions, myasthenia gravis, vocal fold paralysis, and normal laryngeal symmetry. RESULTS: We identified 95 patients who were diagnosed with vocal fold paresis with LEMG who met inclusion and exclusion criteria (mean age 43.8 ± 20.4 years (18-88), 38.9% male). When comparing the laterality of the observed laryngoscopic finding with LEMG, we found that in patients who had severe true vocal fold (TVF) range of motion disturbance, the laterality of the finding matched the LEMG distribution of paresis in 12 out of 13 (92.3%) patients (P = 0.002). No other laryngoscopic findings reliably predicted laterality including corniculate and cuneiform cartilage asymmetry, pyriform sinus dilation, abnormal TVF show, petiole deviation, abnormal ventricular show, increased supraglottic area, and FVF hyperfunction of the opposite side. CONCLUSION: With the exception of severe TVF range of motion disturbance, there seems to be poor validity of laryngoscopic findings in predicting the affected side in vocal fold paresis. We recommend neurophysiologic testing to confirm the clinical diagnosis of vocal fold paresis.

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OBJECTIVE: To assess long-term outcomes of ALA-PDT in treating recalcitrant laryngeal leukoplakia. STUDY DESIGN: Retrospective Case-Control. METHODS: We reviewed all laryngeal leukoplakia patients treated with ALA-PDT compared with angiolytic laser treatment alone (585 nm PDL or 532 nm KTP laser) from 2000 to 2019. Patients with laryngeal cancer (or a history of laryngeal cancer), leukoplakia previously treated with radiation and no pathologic report were excluded. Patient demographics, procedure details and outcomes were examined including histopathologic diagnosis, procedures performed, ALA usage, recurrence of leukoplakia and the development of cancer. RESULTS: We identified 132 patients with laryngeal leukoplakia: 42 were treated with ALA-PDT and 90 were treated with an angiolytic laser alone (Laser group). The proportion of cases of high-grade dysplasia was 57.1% in the ALA-PDT group compared to 32.2% in the Laser group. In high-grade dysplasia cases, there was a statistically significant better recurrence-free survival (RFS) at 12 months and 60 months in those who underwent ALA-PDT 71.4% and 7.1% vs Laser 25% and 0% (p = .01). However, for overall groups, there was no difference in RFS (p = .25). Voice outcomes (patient subjective report) improved or were stable in 75% of subjects with no serious side effects reported. CONCLUSION: ALA-PDT for recalcitrant and high-grade dysplasia is highly effective with improved recurrence-free survival compared to laser alone. ALA-PDT may be an appropriate therapy in patients who have failed prior angiolytic laser alone.

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OBJECTIVE: Patients consider many factors when deciding how to receive medical care. This study used best-worst scaling (BWS), a technique novel to otolaryngology, to quantitatively examine preferences among patients choosing a laryngologist. Our objective was to quantify in a pilot cohort the relative importance patients place on a variety of attributes when seeking a laryngologist. STUDY DESIGN: BWS survey. SETTING: Academic voice clinic. METHODS: New patients were recruited to take a computerized BWS survey developed using attributes derived from patient input, expert opinion, and literature review. Attributes were grouped into 4 categories: physician reputation, physician qualifications, hospital-related factors, and other nonclinical factors. Responses were analyzed using multinomial logit regression to determine importance scores and associations with other variables. RESULTS: Eighty-seven of 93 patients recruited participated (93.5% response rate). Physician qualifications were the most important attributes to patients, with specialty laryngology training receiving the highest importance score (20.8; 95% CI, 20.2 to 21.5; P < .0001). Recommendations from referring physicians (15.6; 95% CI, 14.3 to 16.9) and use of cutting-edge technology (11.9; 95% CI, 10.7 to 13.1) were the second and third most important, respectively. Least important were nonclinical factors, including wait time to get an appointment (4.3; 95% CI, 2.8 to 5.8) and convenience of office location (1.5; 95% CI, 0.9 to 2.1). Just over half of patients (51.2%) reported willingness to wait 4 weeks for an appointment with a laryngologist. Older patients were less concerned with convenience-related factors. CONCLUSION: Nonclinical factors were less important to patients than clinical factors, and laryngology-specific training was paramount. Stated preference methodologies can elucidate underlying preferences and help providers make care more patient centered.

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Over the past two decades, several researchers have demonstrated that changes in the acoustic nonlinearity parameter ß can be related to changes in material properties due to mechanical and/or thermal degradation processes. Generally, a piezoelectric sensor-based detection method is used to measure changes in ß values because it is operationally simpler than the complex capacitive detection method. However, this method is limited to measuring only relative changes in ß values; whereas, the absolute ß values of components in service often need to be measured in the field to quantify the degradation level. Accordingly, a novel field-deployable method for measuring absolute ß values was developed in this study. Nonlinear ultrasonic experiments were conducted using capacitive detection, conventional piezoelectric sensor-based detection, and proposed detection methods, and the results were compared. The ß values of a copper single-crystal sample measured using the new and the capacitive detection methods were 2.49 and 2.1, respectively, and those obtained using the conventional piezoelectric sensor-based detection method ranged between 90 and 130. The test results confirm that the proposed field-deployable measurement method produces more consistent absolute ß values without involving the complexity of the capacitive detection method.

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PURPOSE: To assess the incidence and severity of 12 systemic side effects of serial intralesional steroid injections (SILSI) in patients with idiopathic subglottic stenosis (iSGS). METHODS: This retrospective study included patients with iSGS who underwent SILSI with Triamcinolone 40 mg/dL. After SILSI, the patients were asked to answer 12 questions regarding frequently encountered systemic side effects of steroids. Each answer was rated as mild, moderate, or severe. Descriptive statistics were used to analyze and present the findings. RESULTS: The study included 49 patients (42 female and 7 male) with a mean age of 59.1 years (range 21-83 years). Post-SILSI treatment, 27 (55%) reported experiencing side effects while 22 (45%) patients reported no side effects. The most frequent side effect reported in women of reproductive age (n: 8) was menstrual irregularities (3/8, 37%). Other frequently reported side effects were feeling joyful and sleeping difficulties, each reported by 30% of the patients. All side effects resolved after the completion of SILSI. CONCLUSIONS: SILSI can be administered with minimal tolerable side effects. Clinicians should make their patients aware of the most frequent side effects. Special attention should be given to women of reproductive age to inform them of the possibility of menstrual irregularities during SILSI.

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OBJECTIVE: To determine the effectiveness of nortriptyline and tolerability of side effects in the treatment of neurogenic cough. Secondary goal is to evaluate the association between laryngeal asymmetry and clinical response to nortriptyline. STUDY DESIGN: Retrospective case series. MATERIALS AND METHODS: Consecutive patients diagnosed with neurogenic cough at a quaternary care specialty hospital from 2001 to 2020 were identified. Subjects <18 years old, not treated with nortriptyline, did not have a nasolaryngoscopic examination and were lost to follow-up were excluded. Charts were reviewed for demographic information, clinical history, nasolaryngoscopic findings, medication dosage, side effects, and follow-up time. RESULTS: Forty-two patients met inclusion and exclusion criteria, 7 males and 35 females with an average age of 56.5 (±13.1) years. There were 26/36 (72.2%) responders and 10/36 (27.8%) non-responders; 6 patients stopped nortriptyline due to side effects and were not included in the response comparison. Laryngeal asymmetry was present in 36/42 (85.7%) patients. No factors related to laryngeal asymmetry were significantly different between responders and non-responders. Medication tolerance was observed in 3/42 (7.1%) patients. Side effects were reported in 16/42 (38.1%) patients. The most common side effects were sedation 9/42 (21.4%) and xerostomia 3/42 (7.1%). CONCLUSION: Nortriptyline is effective for treating neurogenic cough with 72% of patients reporting improvement in cough. Evidence of laryngeal asymmetry was not associated with better treatment response. Although 38% experienced side effects, the majority of patients continued nortriptyline despite side effects. LEVEL OF EVIDENCE: 4.

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OBJECTIVE: To determine the reliability of pulmonary function testing compared to endoscopic grading in the assessment of subglottic stenosis. METHODS: Consecutively treated patients with subglottic stenosis at a tertiary care specialty hospital from 2009 to 2019 were identified. Two fellowship-trained laryngologists and two otolaryngologists blinded to clinical history reviewed laryngo tracheoscopic examinations and assessed the degree of stenosis using the Cotton-Myer grading system (% stenosis). Nine full flow-volume loops were performed at the time of each exam. RESULTS: The endoscopic images of 45 subjects were graded for degree of stenosis and the spirometry data were analyzed. The kappa values for Cotton-Myer grade overall was 0.37, grade I was -0.103, grade II was 0.052, and grade III was 0.045. The overall intraclass correlation of the physician grading of estimated percent obstruction (% stenosis) was 0.712 (P < .01) whereas the overall intraclass correlation for PEF% was 0.96 (P < .01). Within each Cotton-Myer grade, the intraclass correlation for % stenosis was 0.45 (P = .02) for grade I, 0.06 (P = .30) for grade II, and 0.16 (P = .03) for grade III. The intraclass correlation for PEF% for grade I was 0.97 (P < .01), grade II was 0.92 (P < .01), and grade III was 0.96 (P < .01). CONCLUSION: Cotton-Myer grading and estimating percent obstruction (% stenosis) for adult subglottic stenosis showed poor reliability as an assessment tool compared to the excellent intraclass correlation seen with pulmonary function tests within each Cotton-Myer grade subgroup. We recommend pulmonary function testing, specifically PEF% because it is a normalized value, for the assessment and management of subglottic stenosis. LEVEL OF EVIDENCE: 4.

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Ultrasonic inspection of welds joining dissimilar metals in nuclear power plants has proven to be a challenge, because the ultrasonic waves are subject to diffraction, distortion, scattering, and noise. These perturbations are due to their interactions with coarse-grained microstructures having anisotropic and heterogeneous metallurgical properties that can promote ultrasonic attenuation. In this paper, to improve the reliability of ultrasonic testing for dissimilar-metal welds (DMWs), ultrasonic beam characteristics for DMWs with a buttering layer were investigated in order to analyze the beam distortion phenomenon caused by inhomogeneous anisotropic properties and coarse grains. Ultrasonic testing was performed on DMW specimens using single ultrasonic transducers to investigate the behavior of the ultrasonic beam in the welds. According to the anisotropic and heterogeneous properties, when passing through the weld and the buttering layer of the DMW, ultrasonic waves were distorted and attenuation was high. In particular, in the case of using angular incidence that passed through the weld and the buttering layer in turn, the received ultrasonic data did not contain accurate internal information. From this, it was verified that internal defects may be detected by transmitting ultrasonic waves in different directions. Finally, the existing limitations on the application of non-destructive ultrasonic testing to dissimilar-metal welds were verified, and a solution to the measurement method was proposed.

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Ventilation during microlaryngoscopy previously included jet ventilation, microlaryngeal endotracheal tubes, and extended apnea. Historically, apneic oxygenation provided a tubeless field but limited operative time. Increased utilization of high-flow nasal cannula in intensive care units and operating rooms has created new opportunities to expand tubeless microlaryngoscopy. Although few studies have described high-flow nasal cannula for microlaryngoscopy, there remains much to be explored. In this case report, we describe the unique setting of utilizing high-flow nasal cannula in a spontaneously breathing patient to create an optimal tubeless surgical field for both microlaryngoscopy and vocal cord electromyography.

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Ultrasonic flaw classification in weldment is an active area of research and many artificial intelligence approaches have been applied to automate this process. However, in the industrial applications, the ultrasonic flaw signals are not noise free and automatic intelligent defect classification algorithms show relatively low classification performance. In addition, most of the algorithms require some statistical or signal processing techniques to extract some features from signals in order to make classification easier. In this article, the convolutional neural network (CNN) is applied to noisy ultrasonic signatures to improve classification performance of weldment defects and applicability. The result shows that CNN is robust, does not require specific feature extraction methods and give considerable high defect classification accuracies even for noisy signals.

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OBJECTIVE: The objective of this study is to review the published literature on supraglottoplasty techniques for correcting laryngomalacia, and to subsequently provide a standardized classification system. METHODS: Three authors independently and systematically searched Pubmed/MEDLINE and six additional databases for all studies that included descriptions of supraglottoplasty techniques for correcting laryngomalacia. Sub-sites operated on and specific technique descriptions were reviewed, cataloged and subsequently categorized. This data was then used to develop a new classification system. RESULTS: 231 articles were identified, downloaded and reviewed in full text. 53 articles with 1669 patients from the included articles described in detail the supraglottoplasty procedure. 84 articles with 5731 patients had to be excluded secondary to not providing detail about the supraglottoplasty procedure. The resultant data identifies the need for a more standardized reporting of the supraglottoplasty procedure in order to more accurately evaluate technique specific outcomes. Currently 77% of the patients in the literature cannot be assessed for outcomes as they did not describe the details for the procedures. Eight variations of supraglottoplasty and four variations of epiglottis surgery were described. Based on the literature, we consolidated the surgery into the following types: Type 1: Debulking of arytenoids, Type 2: Division of aryepiglottic folds, Type 3: Epiglottis surgery. CONCLUSION: This descriptive review identified 53 articles with 1669 patients from the included articles detailing multiple variations of supraglottoplasty techniques. The new classification supplements a previously established system describing laryngomalacia, and simplifies the supraglottoplasty into three descriptive and logical types of categories. Our classification system would give surgeons a universal language to describe the supraglottoplasty performed, which could improve reporting of techniques, and facilitate future communication and research.

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