• The korean journal of orthodontics
• /
• v.38 no.2
• /
• pp.74-82
• /
• 2008

Objective: This study examined the craniofacial morphology of young patients in their prepubertal stage showing class I, II malocclusion, by analyzing lateral cephalograms, and analyzed its relationship with tongue position, tongue space, and airway space in order to ascertain the effects of nasopharyngeal airway and tongue morphology on the form of the malocclusion. Methods: Seventy-six patients aging from 9 to 11 were divided into two groups depending on the ANB difference on the lateral cephalogram: Experimental group (CI II malocclusion group) showing $0{\le}ANB$ difference < 4.0; Control group (CI I malocclusion group) showing $0{\le}ANB$ difference < 4.0. The tongue space, space between palate and tongue, nasopharyngeal airway space and craniofacial morphology were compared between the two groups. Results: Tongue space, palate-tongue space, nasopharyngeal airway space showed no significant differences between class I and class II malocclusion groups. Hyperdivergent faces were associated with smaller nasopharyngeal airway space. Longer anterior facial height and posterior facial height were associated with larger tongue space, and greater anterior facial height were associated with lower tongue position. Smaller nasopharyngeal airway space showed smaller tongue space. Conclusions: Tongue space and nasopharyngeal airway space showed no significant differences between class I malocclusion group and class II malocclusion group. Only anterior facial height and posterior facial height had an influence on tongue space and nasopharyngeal airway space.

• The korean journal of orthodontics
• /
• v.25 no.1 s.48
• /
• pp.19-29
• /
• 1995

This study was performed to compare the size of soft palate, tongue and airway according to the types of the malocclusion and evaluate the correlation between the size of soft palate, tongue, airway and dentofacial skeleton respectively. The sample of this study was 98 malocclusion female patients between the ages 12 and 17 years. The lateral cephalometric radiographs were taken and the distance, angle, ratio and area of the dentofacial skeleton, soft palate, tongue and airway were measured and evaluated statistically. The results obtained were as follows: 1. There was significant difference in SNB, ANB, facial angle, facial convexity, A-B plane angel, Y axis to FH, SN-MP, Wits appraisal, ODI and APDI according to the types of malocclusion. 2. The hyoid bone was more posteriorly positioned in Class II malocclusion group than other two groups and superio-inferior position of the hyoid bone was not different according to the malocclusion types. 3. The nasopharyngeal area of Class II and Class III malocclusion group was smaller than that of Class I malocclusion group, and the pharyngeal area of Class II malocclusion group was smaller than that of Class I and Class III maocclusion group. There was no difference of the area of the soft palate, tongue, oropharynx and hypopharynx according to malocclusion types. 4. The ramal height and mandibular body length(Go-Me) showed positive correlation with the area of tongue, nasopharynx, oropharynx, and pharynx. SNA did not correlated with the area of tongue and airway but SNB showed positive correlation with the area of hypopharynx and pharynx. The anterior, posterior facial height, upper and lower central incisor position to facial plane showed positive correlation with tongue area.

• Tuberculosis and Respiratory Diseases
• /
• v.42 no.6
• /
• pp.813-822
• /
• 1995

Background: Bronchial hyperresponsiveness and abnormal response such as a loss of distensibility are pathophysiologic characteristics if bronchial asthma. The only means of direct in vivo measurement of airway size had been a tantalium bronchography, until high-resolution computed tomography(HRCT) enabled to measure noninvasively two dimensional airway area more accurately and reliably. Method: To investigate airway area responses to bronchial provocation with methacholine and evaluate the major sites of bronchial constriction in patients with bronchial asthma. We examined HRCT scans in five patients with bronchial asthma who had significant bronchoconstriction(20% or more decrease in $FEV_1$) using CT scanner(5,000T CT, Shimadzu Co, Japan) before and in 3~5 min. after methacholine inhalation. Airways which were matched by parenchymal anatomic landmarks in each patient before and after methacholine inhalation were measured using film scanner(TZ-3X scanner; Truvel Co. Chatsworth CA, USA) and a semiautomated region growing method. Results: 1) We identified 9 to 12 airways in each patient which were matched by parenchymal anatomic landmarks before and after methacholine inhalation. 2) Airway responses to methacholine are quite different even in a patient. 3) The constriction of small airways(average diameter <2 mm; area < $3.14mm^2$) was 48.7%(8.3; SEM, n=43), being more prominant than that of large airways(average diameter >2 mm; area > $3.14mm^2$), 53.8% (4.4;SEM, n=10), but not significantly different(p>0.05). 4) There was no significant difference in the degree of constriction between upper(44.3% +5.8; mean + SEM, n=30) and lower lung regions(56.7% +4.5, n=23). Conclusions: Thus airway responses to methacholine bronchoprovocation is quite variable in a patient with bronchial asthma and has no typical pattern in patients with bronchial asthma.

• Sleep Medicine and Psychophysiology
• /
• v.6 no.2
• /
• pp.110-115
• /
• 1999

Objectives: To investigate the effect of mandibular repasitioning device on airway sige and airway collapsibility in patients with obstructive sleep apnea syndrome(OSAS). Methods: Cine CT with polysomnographic monitoring was performed during sleep in nine(OSAS) patients before and after manibular repositioning device(MRD) application. Axial CT images were obtained in five upper airway levels(retropalatal-high, retroalatal-low, retroglossal, epiglottis, and hypopharynx levels). In each airway level, one axial CT image was obtained during sleep apnea period and 10 serial axial CT images were scanned every 1 second during normal sleep breathing. After wearing MRD, all CT images were obtained by the same method. The cross-sectional areas of airway were measured by automatic tracing method. The changes of minimum airway size and maximum airway size after MRD were evaluated. The airway collapsibility was calculaed before and after MRD. Results: During sleep apnea, the airway of retropalatal-low level was the most frequently narrowest site. During normal sleep breahing the minimum airway size was increased significantly after MRD at retropalatal-low level(p=0.011). The mean airway collapsibility was the highest at retropalatal-low level. MRD decreased the airway collapsibility significantly at retropalatal-low level(p=0.021) and epiglottis level(p=0.038). Conclusions: The enlargement of the minimum airway size and decreased airway collapsibility may be the therapeutic mechanism of MRD in obstructive sleep apnea.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.4
• /
• pp.201-209
• /
• 2014

Obstructive sleep apnea syndrome(OSAS) is a respiratory disease caused by partial or complete obstruction of the upper airway during sleep. In this paper, we proposed the optical flow method to analyze the upper airway dynamic changes during respiration for children with OSAS and control subjects. We compared the absolute value of difference between inspiration and expiration for airway area analysis method and optical flow method for 5 children with OSAS and 6 control subjects. From the statistical analysis, airway area analysis method and optical flow method are statistically significant at the 0.1 (p value is 0.0977) and 0.01 (p value is 0.0011) significance level respectively. From this simulations, the optical flow method could provide more accurate information to diagnose the OSAS patients than the traditional airway area analysis method.

• The korean journal of orthodontics
• /
• v.26 no.1 s.54
• /
• pp.43-52
• /
• 1996

The purpose of this study was to compare and evaluate the upper airway structure between the snorers and asymptomatic control subjects depending on the positional change. Lateral cephalograms in the upright and supine position were taken in 25 female snorers and 20 female asymptomatic control subjects. The length and the area of the soft palate, tongue and airway were measured and evaluated statistically. The results obtained were as follows : 1. The snorers showed longer and higher tongue, narrower and longer airway, inferiorly positioned hyoid bone, longer and broader soft palate and narrower hypopharynx than the control subjects both in the upright and supine position. In addition, the snorers showed broader tongue area and narrower oropharynx area than the control subjects in supine position. 2. Depending on the positional change from upright to supine position, the controls and the snorers showed decreased airway length and superior positioned the hyoid bone. In addition, the snorers showed decreased tongue length and height, airway length and thickness and oropharynx area, but increased tongue area and soft palate area.

• The korean journal of orthodontics
• /
• v.26 no.4
• /
• pp.373-387
• /
• 1996

The purpose of this study was to evaluate the growth pattern of nasopharyx and adenoid and to obtain useful measurements for evaluating the fuction of the nasal breathing. The biennial serial cephalometric radiographs of 33 samples(19 male, 14 female) with normal occlusion from 8.5 years to 18.5 years of age were used in this study. The distances, areas and ratios on nasopharynx and adenoid were measured and analyzed in each age and sex. The results of this study might be summarized as follows ; 1. The mean value and standard deviation of each measurement was obtained in each age and sex. 2. The nasopharyngeal height and the nasopharyngeal depth increased significantly by 14.5 years of age in male and 12.5 years of age in female(p<0,05), 3. The relative nasal airway area showed the minimal value at 8.5 years of age and showed significant increase from 10.5 years to 12.5 years of age in male and from 12.5 years to 14,5 years of age in female(p<0.05). 4. In the correlation analysis between the measurements on the nasal airway and the measurement of relative nasal airway area, the measurements of Ad2-PNS, Ad2-PNS/Ho'-PNS and Upper pharynx appeared singnificant correlation with the measurement of relative nasal airway area(p<0.01).

• Tuberculosis and Respiratory Diseases
• /
• v.54 no.2
• /
• pp.191-198
• /
• 2003

Background : The pathological features in asthmatic airway remodeling are diverse. The aim of this study was to examine the degree of airway vascularity in relation to the other remodeling parameters in asthmatics. Methods : Bronchial biopsies were done in 34 asthmatic patients, and 6 control subjects. The basement membrane thickness and the subepithelial thickness were measured in the hematoxylin-eosin stained tissue, and the degree of vascularity was measured using type IV collagen immunostaining. Results : 1) Compared to the control subjects, the asthmatics showed a significant increase in the basement membrane thickness ($6.92{\pm}2.01{\mu}m$ vs $9.67{\pm}2.84{\mu}m$, p<0.05) and the subepithelial thickness ($44.49{\pm}31.92{\mu}m$ vs $121.22{\pm}72.79{\mu}m$, p<0.05). 2) Compared to the control subjects, the asthmatics showed a significant increase in the vascular area per unit submucosal area ($4.51{\pm}2.13%$ vs $10.32{\pm}6.08%$, p<0.05). In addition, the number of vessels per unit submucosal area showed an increased tendency without statistical significance. 3) In the asthmatics, the number of vessels and the vascular area per unit submucosal area showed no correlation with the basement membrane thickness, the subepithelial thickness, the severity, the forced expiratory volume in 1 second($FEV_1$), and the methacholine provocative concentration 20($PC_{20}$). Conclusion : This study showed that vascularity was an important parameter in asthmatic airway remodeling but it was not related to the other remodeling parameters such as the basement membrane thickness and the subepithelial thickness. Each of these asthmatic remodeling parameters may have a different clinical significance. Therefore, further studies will be needed.

• The korean journal of orthodontics
• /
• v.27 no.5 s.64
• /
• pp.733-741
• /
• 1997

As a result of surgical orthodontic treatment of mandibular prognathism, changes take place in the skeletal and soft orofacial components. Although some investigators had stated that permanent reduction of airway space was observed after mandibular setback surgery, it was not clear that this permanent reduction was sustained during long-term follow-up. The purpose of this study was to assess the changes in oropharyngeal airway space and soft tissue orofacial component following the mandibular setback surgery and during the follow-up period. The correlation between the changes of the oropharyngeal airway space and the changes of other soft tissue orofacial component was also assessed. The findings of this study were as follows ; 1. The oropharyngeal airway space area decreased following mandibular setback surgery for mandibular prognathism and continued to decrease during the follow-up period(p<0.05). 2. The pharyngeal depth at Xi point level and the 2nd cervical vertebra point level decreased after the surgery and remained during the follow-up period(p<0.05). The decrease of these pharyngeal depth was correlated with the decrease of oropharyngeal airway space area(p<0.01). 3. The decrease of pharyngeal depth at the 3rd and 4th cervical vertebra point level was not significant after the surgery and during the follow up period. 4. The hyoid bone moved downward after the surgery(p<0.05), but returned to its original position during the follow-up period. 5. The length & height of tongue and the Position of epiglottis base did not change significantly(p>0.05). 6. The soft palate was displaced posteriorly after the surgery and remained to its changed position during the follow-up period(p<0.05) due to posterior displacement of tongue. The changes of soft palate were significantly correlated with the decrease of oropharyngeal airway space area(p<0.01). 7. The narrowing of oropharyngeal airway space was due to the posterior displacement of tongue above the level of epiglottis tip. The posterior displacement of tongue following mandibular setback osteotomy remained during the follow-up period.

• Proceedings of the Korean Information Science Society Conference
• /
• 2007.10b
• /
• pp.194-197
• /
• 2007

본 논문에서는 모바일용 3차원 그래픽 라이팅 엔진을 위한 부동소수점 멱승기클 제안한다. 3D 그래픽의 라이팅 과정은 연산량이 많고, 복잡하기 때문에 각 연산 유닛들이 저비용으로 빠르게 연산을 수행해야 한다. 본 논문에서 제안한 멱승기는 처리율을 높이기 위해 파이프라인 구조를 사용하였으며, $10^{-4}$의 정확도를 만족한다. 전체 구조는 5 stage로 구성되며, 크게 로그연산기와 지수연산기로 이루어져 있다. 일반적으로 로그연산기는 정확도를 높이기 위하여 큰 롬 테이블을 사용하는데, 이는 많은 면적을 차지하게 된다. 이러한 롬 테이블 면적 문제를 해결하기 위하여 Newton method을 사용하여 롬 테이블의 사이즈를 줄였다. 또한 오일러 상수를 밑으로 하는 지수연산기도 입력 비트의 크기를 줄이고, 테이블의 개수를 늘림으로써 롬 테이블의 크기를 줄였다. 지수연산의 밑은 부동소수점 포맷으로 [0, 1]의 범위를 가지며, 승은 정수 포맷으로 [0, 128]의 범위를 갖는다. Magnachip $0.18{\mu}m$ 공정에서 100Mhz의 동작주파수를 만족하였으며, 약 16k gates을 차지한다.