• The korean journal of orthodontics
• /
• v.28 no.3 s.68
• /
• pp.461-477
• /
• 1998

To evaluate the relapse pattern and long-term stabilities depanding on surgical methods following orthognathic surgery of Cl III patients, the author selected 24 subjects(10 male, 14 female) operated by SSRO and 26 subjects(10 male,16 female) operated by IVRO. Each subject took four lateral cephalograms : just before surgery(T1), within 48hrs after surgery(T2), 4-8 wks after surgery(T3), 6 month or more after surgery(T4), and the landmarks were digitized. The differences of relapse patterns in each interval between two groups were compared and the significance of correlation among the variables of each group was tested. The obtained results are as follows ; 1. Horizontal early relapse was forward movement of mandible in SSRO group, as compared to the backward movement in IVRO group, and there was a statistical significance between the two groups. 2. Vertical early and late relapses were decreases in anterior facial height in both groups and there was no statistical significance between the two groups. 3. There was a statistical significance in negative correlation between mandibular horizontal late relapse and surgical change of articular angle in SSRO group. 4. There was a statistical significance in negative correlation between amount of mandibular set-back and mandibular horizontal early relapse in both groups.

• Progress in Medical Physics
• /
• v.24 no.2
• /
• pp.85-91
• /
• 2013

At present, megavoltage computed tomography (MVCT) is the only method used to correct the position of tomotherapy patients. MVCT produces extra radiation, in addition to the radiation used for treatment, and repositioning also takes up much of the total treatment time. To address these issues, we suggest the use of a video image-guided setup (VIGS) system for correcting the position of tomotherapy patients. We developed an in-house program to correct the exact position of patients using two orthogonal images obtained from two video cameras installed at $90^{\circ}$ and fastened inside the tomotherapy gantry. The system is programmed to make automatic registration possible with the use of edge detection of the user-defined region of interest (ROI). A head-and-neck patient is then simulated using a humanoid phantom. After taking the computed tomography (CT) image, tomotherapy planning is performed. To mimic a clinical treatment course, we used an immobilization device to position the phantom on the tomotherapy couch and, using MVCT, corrected its position to match the one captured when the treatment was planned. Video images of the corrected position were used as reference images for the VIGS system. First, the position was repeatedly corrected 10 times using MVCT, and based on the saved reference video image, the patient position was then corrected 10 times using the VIGS method. Thereafter, the results of the two correction methods were compared. The results demonstrated that patient positioning using a video-imaging method ($41.7{\pm}11.2$ seconds) significantly reduces the overall time of the MVCT method ($420{\pm}6$ seconds) (p<0.05). However, there was no meaningful difference in accuracy between the two methods (x=0.11 mm, y=0.27 mm, z=0.58 mm, p>0.05). Because VIGS provides a more accurate result and reduces the required time, compared with the MVCT method, it is expected to manage the overall tomotherapy treatment process more efficiently.

• Pediatric Infection and Vaccine
• /
• v.11 no.1
• /
• pp.101-111
• /
• 2004

Purpose : This study was performed to observe the epidemiological pattern of M. pneumoniae pneumonia during the period from 1993 to 2002 and also to see some clinical characteristics of M. pneumoniae pneumonia during recent five years. Methods : We had performed a retrospective analysis of epidemiological pattern of occurrence in 682 patients with M. pneumoniae pneumonia admitted to Department of Pediatrics of Han-il General Hospital from January, 1993 to December, 2002. Results : The annual ratio of M. pneumoniae pneumonia was compared with the total numbers of respiratory tract infection patients. The ratios were 19.1% in 1993, 13.0% in 1994, 5.6% in 1995, 12.8% in 1996, 18.6% in 1997, 22.6% in 1998, 1.1% in 1999, 13.3% in 2000, 9.1% in 2001, 6.0% in 2002, and 19.9% in 2003. The epidemics have occurred in 1993, 1997, 1998, 2000, and 2003 years showing 3~4 year intervals. The peak incidence of age was four to six years old(286 cases; 41.9%) and male-to-female ratio was 1 : 1.1. Monthly distribution showed a high frequency from August to December and the major outbreak occurred in November(119 cases; 17.4%), in October(106 cases; 15.5%), and in December(96 cases; 14.1%) in order of frequency. The most common symptoms were cough (660 cases; 96.8%), fever(569 cases; 83.4%), and sputum(522 cases; 76.5%) in that order. Leukocytosis was observed in 31.2% of patients based on a normal range according to the adjusted age. Increased ESR(${\geq}20mm/hr$) was noted in 42.5% of cases and CRP was positive in 37.8% of cases. On the chest X-ray examination, pulmonary infiltration was noted in 557 cases(81.7%), and the patterns of pneumonic infiltration were bronchopneumonia(78.0%), lobar(35.5%), lobular(19.2%), and interstitial pneumonia(28.7%). Complications were paranasal sinusitis(41 cases), acute otitis media(23 cases), pleural effusion(19 cases). cervical lymphadenitis(18 cases), and glomerulonephritis(1 case). Conclusion : The pattern of M. pneumoniae pneumonia from 1997 to 2003 noted 3~4 year interval with peak monthly distribution of October and November compared with 3 year interval and peak incidence of summer period before 1996.

• The Korean Journal of Nuclear Medicine
• /
• v.30 no.1
• /
• pp.77-85
• /
• 1996

Radioiodine($^{131}I$) has been used for the treatment of Graves' hyperthyroidism since the late 1940's and is now generally regarded as the treatment of choice for Graves' hyperthyroidism who does not remit following a course of antithyroid drugs. But for the dose given, several different protocols have been described by different centers, each attempting to reduce the incidence of long-term hypothyroidism while maintaining an acceptable rate control of Graves' hyperthyroidism. Our goals were to evaluate effective half-life and predict absorbed dose in Graves' hyperthyroidism patients, therefore, to calculate and readminister radioiodine activity needed to achieve aimed radiation dose. Our data showed that the mean effective $^{131}I$ half-life for Graves' disease is 5.3 days(S.D=0.88) and mean biologic half-life is 21 days, range 9.5-67.2 days. The mean admininistered activity and the mean values of absorbed doses were 532 MBq(S.D.=254), 112 Gy (S.D.=50.9), respectively. The mean activity needed to achieve aimed radiation dose were 51MBq and marked differences of $^{131}I$ thyroidal uptake between tracer and therapy ocurred in our study. We are sure that the dose calculation method that uses 5 days thyroidal $^{131}I$ uptake measurements after tracer and therapy dose, provides sufficient data about the effective half-life and absorbed dose of $^{131}I$ in the thyroid and predict the effectiveness of $^{131}I$ treatment in Graves' hyperthyroidism.

• Tuberculosis and Respiratory Diseases
• /
• v.47 no.3
• /
• pp.339-346
• /
• 1999

Background : Non-small cell lung carcinoma is a common tumor with a poor prognosis. Of all malignancies, it is the main cause of death for male and female patients in the Western world. Resection remains the most effective treatment when feasible. Accurate description and classification of the extent of cancer growth are important in planning treatment, estimating prognosis, evaluating end results of therapy, and exchanging information on human cancer research. Until effective systemic therapy is available for non-small cell lung cancer, development of new treatment strategies depends on knowledge of the end results achieved for carefully staged groups of patients in the lung cancer populations. For these reasons, we investigated the survival rate in radically resected non-small cell lung cancer patients by newly revised staging system adopted by the American Joint Committee on Cancer and the Union Internationale Contre le Cancer. Methods: Clinical, surgical-pathologic and follow-up informations on 84 consecutive, previously untreated, patients who received their primary treatment for non-small cell lung cancer were investigated. Staging definitions for the T(primary tumor), N(reginal lymph node), and M(distant metastasis) components were according to the International Staging System for Lung Cancer. Death from any causes was the primary target of the evaluation. Results: The median survival rates were as follows; stage I ;79.1 months, stage II ;47.3 months, stage IIIa; 22.7 months, stage IIIb; 16.1 months, and stage IV;15.2 months versus newly revised stage Ia;58.5 months, stage I b;76.0 months, stage IIa; not available, stage IIb;43.0 months, stage IIIa;22.5 months, stage IIIb; 16.1 months, and stage IV;15.2 months. The survival rates were not significantly different between old and newly revised staging system. Cumulative percent survival at 36months after treatment was 100% in stage Ia, 80% in stage Ib, not available in stage IIa, 26 % in stage IIb, and 21 % in stage m a respectively. Conclusions: Although these data were not significantly different statistically, the newly revised lung cancer staging system might be more promising for the accurate evaluation of the prognosis in the non-small cell lung caner patients.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.24 no.4
• /
• pp.389-403
• /
• 2008

In Angle's Class III malocclusion, which has higher incidence in Korean than Western, depressed midfacial profile with protruded lower lips and mandible may give rise to many functional, esthetic, psychological, social problems. Due to the different malocclusion incidence according to racial differences, many previous studies focused on the relationship between Class II malocclusion and nasal airway obstruction. Previous studies used lateral cephalography which has limitations of 2 dimensional image with projection error and identification error. Therefore, the purpose of this study was to analyze morphologic differences in the nasal airway between normal occlusion and Angle's Class III malocclusion patients using 3-dimensional facial computed tomography. Thirteen normal occlusion(7 men and 6 women) and sixteen skeletal Class III(7 men and 9 women) patients were selected and 3-dimensional facial computed tomography taking was performed. Comparison between two group in volume and sectional area of nasal airway were carried out. The results were followed. 1. In the comparison of absolute nasal airway volume, oropharyngeal space of experimental group were larger than control group but there are no significant difference in other. 2. In the comparison of relative nasal airway volume, oropharyngeal space of experimental group were larger than control group but there are no significant difference in other. 3. In the oropharyngeal space width on frontal and lateral view, the similar tendency was revealed between two groups. 4. In the lateral curvature of nasal airway, the similar tendency was revealed between two groups.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.38 no.2
• /
• pp.97-109
• /
• 2022

Purpose: This study aims to investigate the risk indicators contributing to implant failure, and analyze the relationship between risk indicators and marginal bone loss (MBL) through long-term follow-up over 3 years. Materials and Methods: From 2003 to 2017, patients' medical charts with a history of dental implant surgery at Chonnam National University Dental Hospital were reviewed retrospectively. The patient's demographic variables, and clinical variables were recorded. Periapical radiographs were used to evaluated the changes in MBL around implants. And we analyzed implant survival rates. Multiple regression analysis with backward elimination was conducted to correlate the patient's clinical variables and implant failure and Pearson correlation analysis was performed to the correlated between implant long-term survival rates and MBL and initial stability. Results: In multiple regression analysis, there was a statistically significant negative correlation between abutment connection type (β = -.189, P < .05), with or without SPT (β = -.163, P < .05), diabetes (β = -.164, P < .05), osteoporosis (β = -.211, P < .05) and MBL. Anticoagulant medication influenced the long-term success rate of implants. PTV values at the second implant surgery showed a statistically significant negative correlation with long-term implant survival (P < .05). Conclusion: For the long-term success of the implant, the appropriate abutment connection type must be selected and the periodic SPT is recommended. Systemic diseases such as diabetes and osteoporosis and anticoagulant medication should be considered. Furthermore, since high PTV at the second implant surgery correlated with the long-term survival rates of the implant, initial stability should be carefully considered before undergoing the prosthetic procedure.

• The Korean Journal of Nuclear Medicine
• /
• v.38 no.6
• /
• pp.492-497
• /
• 2004

Purpose: it is very important to differentiate breast cancer from benign mass. There are many reports to evaluate the differential diagnosis under the several diagnostic tools. We evaluated the usefulness of mammography and Tc-99m MIBI scintimammography in the differential diagnosis of breast mass and correlated with pathologic findings. Materials and Methods: This study included 80 patients (a8e: 24-72, mean: 48.4) who underwent mammography and Tc-99m MIBI scintimammography for breast masses. Scintimammographies (anterior-posterior and lateral projections) were acquired in 10 minutes and 2 hours after intravenous injection of Tc-99m MIBI. four specialists in diagnostic radioloay and nuclear medicine evaluated the findings of breast masses under the mammography and Tc-99m MIBI scintimammography, and calculated the tumor to background (T/B) ratio. The pathologic results were obtained and we statistically analyzed the correlations between pathologic results and imaging findings under the mammography and Tc-99m MIBI scintimammography by chi-square and correlation test. Results: The sensitivity, specificity, positive predictive value, and negative predictive value of mammography for detection of breast cancer were 87.5%, 56.3%, 75.0%), and 75.0% respectively. 45 cases of 80 patients were suspicious for breast cancer under the Tc-99m MIBI scintimammography. 41 cases of 45 patients were confirmed as breast cancer and the remaining 4 cases were confirmed as benign masses. The sensitivity, specificity, positive predictive value and negative predictive value of Tc-99m MIBI scintimammography for detection of breast cancer were 85.4%, 87.5%, 91.1%, and 80.8% respectively. The sensitivity of scintimammography was lower than that of mammography for detection of breast cancer, however the specificity, positive predictive value, and negative predictive value were higher. In the benign mass, the mean T/B ratio in 10 minutes was $1.409{\pm}0.30$, and that in 2 hours was $1.267{\pm}0.42$. The maximal T/B ratio of benign mass in 10 minutes was $1.604{\pm}0.42$, and that in 2 hours was $1.476{\pm}0.50$. In the malignant mass, the mean T/B ratio in 10 minutes was $2.220{\pm}1.07$, and that in 2 hours was $1.842{\pm}0.75$. The maximal T/B ratio of malignant mass was $2.993{\pm}1.94$, and that in 2 hours was $2.480{\pm}1.34$. And the T/B ratio under the early and delayed images were meaningful. Conclusion: The scintimammography is useful diagnostic tool to differentiate breast cancer from benign mass, although the sensitivity of mammography for detection of breast mass is high. Especially, the use of the T/B ratio is helpful to diagnose breast cancer.

• The korean journal of orthodontics
• /
• v.29 no.2 s.73
• /
• pp.183-195
• /
• 1999

Growth and development evaluation of patients with growth potential is of great importance for orthodontic treatment planning. Timing of orthodontic intervention greatly depends on one's developmental status, thus if there is a difference in skeletal maturation among malocclusion types different treatment timing should be applied. The objective of this study was to evaluate and compare skeletal maturation among different malocclusion types. The samples used in this study was 38 Class I, 36 Class II and 33 ClassIII females aging from 8 to 10 years. Handwrist X-rays were taken with 6 month interval till 12-13 years of age. The results were as follows. 1. There was no skeletal maturity difference among different malocclusion types. 2. The hamular process of hamate was observed at $9.16{\pm}0.72$ years, pisiform bone at $9.13{\pm}0.71$ years and the ulnar sesamoid at $10.34{\pm}0.84$ years. 3. The timing of epiphyseal capping on the third finger was $10.96{\pm}0.80$ years for distal phalanx and $11.27{\pm}0.87$ years for middle phalanx, $11.12{\pm}0.85$ years for proximal phalanx of the first finger, $11.21{\pm}0.82$ years for radius and $11.62{\pm}0.85$ years for middle phalanx of the fifth finger. 4. The appearance of pisiform bone showed high correlation with appearance of hamular process of hamate(r=0.91) and ulnar sesamoid bone appearance showed high correlation with advanced ossification of hamular process(r=0.86). Timing of epiphyseal capping among different parts showed high correlation(r=0.80-0.90). 5. The shape of middle phalanx of the fifth finger showed the highest variability ($20.6\%$).

• The korean journal of orthodontics
• /
• v.31 no.6 s.89
• /
• pp.601-610
• /
• 2001

The purpose of this retrospective study was to evaluate the level oi alveolar bone support of the erupted Permanent canine through the reconstructed cleft region compared to the contralateral canine on the non-cleft side. This study was limited to children with complete unilateral cleft lip and palate who underwent secondary alveolar iliac bone gvaft and the apices of the erupted canine roots were closed at the time of evaluation. With these criteria the study included 21 children whose average age at the time of bone graft reconstruction was 9.8 years, with a minimum of 12.4 years of age at the time of the evaluation. The study was limited to the use of iliac cancellous bone as the autograft material for reconstruction of the alveolar cleft. Cranial bone graft and other autogenous bone sources were excluded. The periapical radiographs were used to evaluate alveolar bone level of each canine. The percentages of root supported by the bone were established by dividing the amount of root covered with the bone by the anatomic root length. The canine oi the non-cleft side was used as an internal control and the canine on the cleft side was used as an experimental. There was a statistically significant difference in the alveolar bone support ratio between the control ($92.9\%$) and experimental canines ($8.7\%$). An average of $95\%$ level of alveolar bone support was achieved for the experimental canine in comparison to the control canine. Neither the presence of lateral incisor, nor the stage of root development of the canine at the time of the bone graft appeared to have affected the alveolar bone support ratio of the canine after the secondary bone graft.