• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.10 no.1
• /
• pp.50-57
• /
• 1999

A study to get the data of normal stop consonants production as preliminary study for cleft palate patients was performed. Normal Korean native 21 speakers were pronounced $VCV(V=/a/,C=/P/,/{P^1}/,/P^h/,/t/,/{t^1}/,/{t^h}/,/k/,/{k^1}/,/{k^h}/)$ syllables with natural speech rate and intensity. With intrapharyngeal pressure waveforms by pressure sensor in oropharyngeal cavity, amplitude and time duration of intrapharyngeal pressure were analyzed, and with acoustic waveforms and spectrograms, closure duration and VOT were analyzed. As results, the highest amplitude of intrapharyngeal pressure showed in alveolars and heavily aspirated consonants. Velars and unaspirated consonants were higher than bilabials and slightly aspirated ones each, in intrapharyngeal pressure. Bilabilas, alveolars and velars showed similar rise time of intrapharyngeal pressure build-up, but in decay time and total duration time, bilabials were slightly shorter than alveolars and velars, with no statistic significance. In the aspects of tensity, unaspirated consonants showed the longest rise time, heavily aspirated, the second, and slightly aspirated consonants, the shortest, which were also seen in decay time and total duration time. In closure duration, slightly aspirated consonants had the shortest closure duration, and the heavily aspirated ones, the second, and unaspirated consonants showed the longest. In VOT, heavily aspirated consonants showed the longest, slightly aspirated ones, the second and unaspirated ones showed the shortest.

• Clinical and Experimental Pediatrics
• /
• v.60 no.9
• /
• pp.273-281
• /
• 2017

To date, preterm infants with respiratory distress syndrome (RDS) after birth have been managed with a combination of endotracheal intubation, surfactant instillation, and mechanical ventilation. It is now recognized that noninvasive ventilation (NIV) such as nasal continuous positive airway pressure (CPAP) in preterm infants is a reasonable alternative to elective intubation after birth. Recently, a meta-analysis of large controlled trials comparing conventional methods and nasal CPAP suggested that CPAP decreased the risk of the combined outcome of bronchopulmonary dysplasia or death. Since then, the use of NIV as primary therapy for preterm infants has increased, but when and how to give exogenous surfactant remains unclear. Overcoming this problem, minimally invasive surfactant therapy (MIST) allows spontaneously breathing neonates to remain on CPAP in the first week after birth. MIST has included administration of exogenous surfactant by intrapharyngeal instillation, nebulization, a laryngeal mask, and a thin catheter. In recent clinical trials, surfactant delivery via a thin catheter was found to reduce the need for subsequent endotracheal intubation and mechanical ventilation, and improves short-term respiratory outcomes. There is also growing evidence for MIST as an alternative to the INSURE (intubation-surfactant-extubation) procedure in spontaneously breathing preterm infants with RDS. In conclusion, MIST is gentle, safe, feasible, and effective in preterm infants, and is widely used for surfactant administration with noninvasive respiratory support by neonatologists. However, further studies are needed to resolve uncertainties in the MIST method, including infant selection, optimal surfactant dosage and administration method, and need for sedation.

• Journal of Rhinology
• /
• v.25 no.2
• /
• pp.99-102
• /
• 2018

Lateral pharyngoplasty is a surgical option for treatment of obstructive sleep apnea (OSA). Here, we present a case involving a 40-year-old healthy man who underwent surgery, including lateral pharyngoplasty and robotic tongue base resection, for OSA. There were no intraoperative or immediate postoperative complications. However, on postoperative day 3, the patient presented with swelling in the temporal and buccal areas and was diagnosed with subcutaneous emphysema, later confirmed by computed tomography. The patient was carefully monitored under conservative care and discharged without complications. Although subcutaneous emphysema following tonsillectomy is a rare complication and usually resolves with conservative management, in certain cases, it might require surgical intervention. Lateral pharyngoplasty involves tonsillectomy and additional incision along the tonsillar fossa, which makes it susceptible to pharyngeal wall defects and, consequently, subcutaneous emphysema. Additionally, lateral pharyngoplasty and robotic tongue base resection cause pain and might thus contribute to the increase in intrapharyngeal pressure, which might aggravate subcutaneous emphysema. Lateral pharyngoplasty should be performed with meticulous dissection of the superior pharyngeal constrictor muscle. Healthcare providers should be aware of these complications and, upon suspicion of the same, place the patient under close observation to prevent life-threatening situations.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.8 no.1
• /
• pp.18-26
• /
• 1997

There are two types of phonetic study, acoustic and physiologic, for differentiating the three manner categories of Korean stop consonants. On the physiologic studies, there are endoscopic, electromyographic(EMG), electroglottographic(EGG) and aerodynamic studies. In this study, I tried to investigate general features of Korean stops using EGG study for the open quotient of vocal fold and baseline shift during speech, and aerodynamic characteristics for e subglottal air pressure, air flow and glottal resistance at consonants. On the aerodynamic study, the glottalized and aspirated stops may be characterized by e increasing subglottal pressure comparing with lenis stop at consonants. The airflow is largest in the aspirated stops followed by lenis stops and glottalized. The glottal airway resistance (GAR) showed highest in the glottalized followed by the lenis, but lowest in e aspirated during e production of consonants, and showed highest in e aspirated, but low in the glottalized and lenis during the production of vowel. The glottal resistance at consonant showed significant difference among consonants and significant interaction between subject and types of consonant. The glottal resistance at vowel showed significant difference among consonants, and e interaction occured between subject and types of consonant. The electroglottography(EGG) has been used for investigating e functioning of e vocal folds during its vibration. The EGG should be related to the patterns of the vocal fold vibration during phonation in characterizing the temporal patterns of each vibratory cycle. The purpose of this study is to investigate the dynamic change of EGG waveforms during continuous speech. The dynamic changes of EGG waveforms fir the three-way distinction of Korean stops were characterized that the aspirated stop appears to be characterized by largest open quotient and smallest glottal contact area of the vocal folds in e initial portion of vocal fold vibration ; the lenis stop by moderate open quotient and glottal contact area ; but the glottalized stop by smallest open quotient and largest glottal contact area. There may be close relationship between the OQ(open quotient) in the initial voice onset and the glottal width at the time of consonant production, the larger glottal width just before vocal fold vibration results in the smaller OQ of the vocal fold vibration in the initial voice onset. The EGG changes of baseline shift during continuous speech production were characterized by the different patterns for the three types of Korean consonants. The small and less stiffness change of baseline shift was found for the lenis and the glottalized, and the largest and stiffest change was found for the aspirated. On the baseline shift for the initial voice onset, they showed so similar patterns with for the consonant production, larger changed in the aspirated. for the lenis and the glottalized during the initial voice onset, three subjects showed individual difference each other. I suggest at s characteristics were strongly related with articulatory activity of vocal tract for the production of consonant, especially for the aspirated stop. The suspecting factors to affect EGG waveforms are glottal width, vertical laryngeal movement and the intrapharyngeal pressure to neighboring tissue during connected spech. So the EGG may be an useful method to describe laryngeal activity to classify pulsing conditions of the larynx during speech production, and EGG research can be controls for monitoring the vocal tract articulation, although above factors to affect EGG would have played such a potentially role on vocal fold vibratory behavior obtained using consonant production.