OBJECTIVE: The purpose of this study was to compare the static (SFF) and kinetic frictional forces (KFF) of a computer-aided design and computer-aided manufacturing lingual bracket (CAD/CAM-LB) with those of conventional LB (Con-LB) and Con-LB with narrow bracket width (Con-LB-NBW) under 3 tooth displacement conditions. METHODS: The samples were divided into 9 groups according to combinations of 3 LB types (CAD/CAM-LB [Incognito], Con-LB [7th Generation, 7G], and Con-LB-NBW [STb]) with 3 displacement conditions (no displacement [control], maxillary right lateral incisor with 1-mm palatal displacement [MXLI-PD], and maxillary right canine with 1-mm gingival displacement [MXC-GD]; n = 6/group). While drawing a 0.016-inch copper or super-elastic nickel-titanium archwire with 0.5 mm/min for 5 minutes in a chamber maintained at 36.5℃, SFF and KFF were measured. The Kruskal-Wallis method with Bonferroni correction was performed. RESULTS: The Incognito group demonstrated the highest SFF, followed by the 7G and STb groups ([STb-control, STb-MXLI-PD, Stb-MXC-GD] < [7G-MXC-GD, 7G-MXLI-PD, 7G-control] < [Incognito-MXLI-PD, Incognito-control, Incognito-MXC-GD]; p < 0.001). However, there were no significant differences in SFF among the 3 displacement conditions within each bracket group. Within each displacement condition, the Incognito group demonstrated the highest KFF, followed by the 7G and STb groups ([STb-control, STb-MXLI-PD] < Stb-MXC-GD < 7G-MXLI-PD < [7G-control, 7G-MXC-GD] < [7G-MXC-GD, Incognito-MXLI-PD, Incognito-control] < [Incognito-control, Incognito-MXC-GD]; p < 0.001). MXC-GD exhibited higher KFFs than MXLI-PD in the same bracket group. CONCLUSIONS The slot design and ligation method of the CAD/CAM-LB system should be modified to reduce SFF and KFF during the leveling/alignment stage.

Symptomatic vasospasm is still one of the major causes of death and disability in patients who suffer an aneurysmal subarachnoid hemorrhage(SAH). To identify risk factors related to symptomatic vasospasm, to determine the outcome in patients with SAH, and to determine the differences identified risk factors between patients with good and bad outcomes, we performed this retrospective study. From a total of 279 SAH patients who were admitted to our hospital between January 1993 and December 1995, 212 were chosen for study. These were patients who had been admitted within 7 days of SAH, had undergone brain computed tomography(CT) within 3 days of SAH and had survived more than 6 days after SAH. Nine variables were examined as to their relationship to symptomatic vasospasm: age, sex, admission day after SAH, hypertension history, frequency of SAH, clinical grade, CT grade, operation day after SAH, and outcome. Data were analyzed by the univariate and multivariate logistic regression method using the Statistical Analysis System(SAS). Symptomatic vasospasm was demonstrated in 30 cases(14.2%). Univariate analysis showed that admission more than 4 days after SAH(p=0.07), clinical grades III-V(p=0.001), and CT grade III(p=0.00001) were associated with a higher risk of symptomatic vasospasm. When study cases were grouped into either good or bad outcome groups, and multivariate logistic regression analysis was performed, these factors were associated with a higher risk of symptomatic vasospasm only in the good outcome group. This suggests that there is a group of patients with a predisposition to symptomatic vasospasm that is independent of these risk factors, and that in these patients, the outcome may be worse.
Aneurysm* ; Brain ; Cause of Death ; Humans ; Hypertension ; Intracranial Aneurysm ; Logistic Models ; Retrospective Studies ; Risk Factors ; Subarachnoid Hemorrhage*

Clinical evaluation and imaging studies such as magnetic resonance imaging, computed tomography, and/or myelography can localize the pathologic process in most patients with lumbar radiculopathy. However, these studies occasionally fail to demonstrate exactly the cause and site for ongoing radicular symptom. So we evaluated 54 patients for the efficacy of selective nerve root blocks to identify a symptomatic nerve. The lumbar nerve root injections were performed at L3 root in 1 patients, at L4 root in 4 patients, at L5 root in 46 patients, and at S1 root in 3 patients. Among them, forty two patients were done before operation(HNP 32, stenosis 5, spondylolisthesis 5), 9 patients were done after operation due to poor results (root injury 2, infection 2, adhesion 1, incorrect diagnosis 4), and 3 patients had improved radiculopathies following nerve root injection(HNP 2, stenosis 1). The results of the nerve root injections and of the operations were not affected by age and sex. There was a good correlation between the response of the nerve root injection and the result of the operation(p<0.05). The concentration of bupivacaine 0.5% has no additional effect comparing to 0.25%(70%/73.5%) solution in spite of its adverse effect causing transient motor weakness. Additional use of depomedrol(50mg) proved to be no more beneficial. Three patients had Improved symptoms for a long period after nerve root injection which consequently made operation unnecessary. Five patients with previous history of operations had moderate pain relief. In summary, lumbar nerve root injection can be used as a functional diagnostic tool to predict operative result and as a treatment modality following failure of a previous surgery.
Bupivacaine ; Constriction, Pathologic ; Diagnosis* ; Humans ; Magnetic Resonance Imaging ; Myelography ; Radiculopathy ; Sciatica* ; Spondylolisthesis

This experiment was undertaken to study the effects of different ratios of N2O-O2 in N2O- halothane anesthetized rabbits weighing about 4-4.5 Kg. The N2O-O2 ratios were 2:1 (group 1), 3:1 (group 2) and 4:1 (group 3). We measured the mean arterial pressure, intracranial pressure and cerebral pressure and analysed the blood gas and electrolytes in each group and compared each group to the other two. The results are summarized as follow; The mean arterial pressure was 101.7+/-14.6, 92.7+/-11.0 and 89.4+/-15.1mmHg in each group respectively. The mean arterial pressure of the group 3 decreased more significantly than that of group 1. The intracranial pressure was 12.7+/-4.3, 11.8+/-4.2 and 13.6+/-4.6mmHg in each group respectively and was non-significant as compared to other groups. The cerebral perfusion pressure was 90.8+/-13.3, 82.6+/-9.9 and 76.9+/-16.9mmHg in each group respectively and the cerebral perfusion pressure of group 3 decreased more significantly than that of group l. In the blood gas analysis, PaQ2 was 162+/-27, 119+/-13 and 105+/-8 mmHg in each group respectively and was non-significant in respect to other groups. PaCO2 and O2 content were not different significantly in each group and were within normal values. The oxygen saturation was 98.9+/-0.3, 97.8+/-0.4 and 97.6+/-1.1% in each group respectively and group 2 and 3 decreased more significantly than group 1. Na+, Cl-, HCO-(3), pH and BE were not different significantly in each group, pH, BE and HCO-(3) were measured as being slightly low values, but PaCO2 was kept within normal values. These are explained as probably being due to metabolic acidosis. The serum K' was 2.94+/-0.46, 3.07+/-0.44 and 3.40+/-0.7 mEq/1 in each group respectively and the serum K+ of group 3 increased more significantly than groups 1 and 2. With these results, it is suggested that a ratio above a 2:1 ratio of N2O-O2 is more dangerous in halothane-N2O anesthesia.
Acidosis ; Anesthesia* ; Arterial Pressure* ; Blood Gas Analysis ; Electrolytes* ; Halothane* ; Hydrogen-Ion Concentration ; Intracranial Pressure* ; Oxygen ; Perfusion ; Rabbits* ; Reference Values

BACKGROUND: A blow-out fracture is one of the most common facial injuries in midface trauma. Orbital wall reconstruction is extremely important because it can cause various functional and aesthetic sequelae. Although many materials are available, there are no uniformly accepted guidelines regarding material selection for orbital wall reconstruction. METHODS: From January 2007 to August 2012, a total of 78 patients with blow-out fractures were analyzed. 36 patients received absorbable mesh plates, and 42 patients received titanium-dynamic mesh plates. Both groups were retrospectively evaluated for therapeutic efficacy and safety according to the incidence of three different complications: enophthalmos, extraocular movement impairment, and diplopia. RESULTS: For all groups (inferior wall fracture group, medial wall fractrue group, and combined inferomedial wall fracture group), there were improvements in the incidence of each complication regardless of implant types. Moreover, a significant improvement of enophthalmos occurred for both types of implants in group 1 (inferior wall fracture group). However, we found no statistically significant differences of efficacy or complication rate in every groups between both implant types. CONCLUSIONS: Both types of implants showed good results without significant differences in long-term follow up, even though we expected the higher recurrent enophthalmos rate in patients with absorbable plate. In conclusion, both types seem to be equally effective and safe for orbital wall reconstruction. In particular, both implant types significantly improve the incidence of enophthalmos in cases of inferior orbital wall fractures.
Absorbable Implants ; Diplopia ; Enophthalmos ; Facial Injuries ; Follow-Up Studies ; Humans ; Incidence ; Orbit ; Orbital Fractures* ; Orbital Implants ; Retrospective Studies ; Titanium

BACKGROUND: Positron emission tomography(PEFT) using fluorine-18 deoxyglucose(FDG), showing increased FDG uptake and retention in malignant cells, has been proven to be useful in differentiating malignant from benign tissues. We indertook the prospective study to compare the accuracy of the whole-body FDG PET with that of the conventional chest computed tomography(CT) for nodal staging of non-small-cell lung cancers(NSCLC). MATERIAL AND METHOD: FDG PET and contrast enhanced CT were performed in 36 patients with potentially resectable NSCLC. Each Imaging study was evaluated independently, and nodal stations were localized according to the AJCC regional lymph nodes mapping system. Extensive lymph node dissection(1101 nodes) of ipsi- and contralateral mediastinal nodal stations was performed at thoracotomy and/or mediastinoscopy. Image findings were compared with the histopathologic staging results and were analyzed with the McNema test(p) and Kappa value(k). RESULT: The sensitivity, specificity, positive predictive value, and negative predictive value of CT for ipsilateral mediastinal nodal staging were 38%, 68%, 25%, 79%, and 61%, and those of PET were 88%, 71%, 47%, 95%, and 75%(p>0.05, K=0.29). When analyzed by individual nodal group(superior, aortopulmonary window, and inferior), the sensitivity, specificity, positive predictive value, and negative predictive value of CT were 27%, 82%, 22%, 85%, and 73%, and those of PET were 60%, 87%, 92%, and 82%(p<0.05, k=0.27). CONCLUSION: FDG PET in addition to CT appears to be superior to CT alone for mediastinal staging of non-small cell lung cancers.
Electrons ; Humans ; Lung Neoplasms* ; Lung* ; Lymph Nodes ; Mediastinoscopy ; Prospective Studies ; Sensitivity and Specificity ; Thoracotomy ; Thorax ; Tomography, Emission-Computed

BACKGROUND/AIMS: Increasing evidence suggests that manganese deposition in globus pallidus is responsible for MRI signal hyperintensity and for extrapyramidal symptoms in cirrhotics. However, the relationships between blood manganese, the severity of liver dysfunction, the pallidal signal intensity, and neurological signs have not been well established. METHODS: Blood manganese concentrations were measured together with brain MRI and neurological evaluation in six controls, six patients with Parkinson's disease with normal liver function, and fourteen cirrhotic patients with hepatic encephalopathy including six cirrhotics with extrapyramidal symptoms. The neurological state was evaluated using the Columbia scale and the pallidal index (PI). The ratio of globus pallidus to frontal subcortical white-matter signal intensity was measured-multiplied by 100. RESULTS: Pallidal signal hyperintensity was observed in 85.7% of cirrhotics, and the PI was higher in cirrhotics with extrapyramidal signs or high grade varices than those without them, but there was no increase in the Parkinson's disease patients. No correlations were demonstrated between the blood manganese level and PI as well as the Child-Pugh score. The blood manganese level was not significantly different between cirrhotics and other groups. However, there was an overt increase only in two cirrhotic patients with extrapyramidal signs. The Columbia scale did not reveal any correlations with the blood manganese level and the Child-Pugh score. CONCLUSIONS: Cirrhotics with extrapyramidal signs showed a significant increase in PI, but there was no increase in the patients with Parkinson's disease. The PI was not significantly correlated with the blood manganese level. These findings suggest that extrapyramidal signs in cirrhotics might be caused by a different mechanism than those in Parkinson's disease, which could possibly be related with manganese.
Brain ; Globus Pallidus ; Hepatic Encephalopathy ; Humans ; Liver ; Liver Diseases ; Magnetic Resonance Imaging ; Manganese* ; Parkinson Disease ; Varicose Veins

Omental leiomyosarcomas are rare intra-abdominal tumors. This report describes a case of primary leiomyosarcoma of the greater omentum. A 76-year-old female complained of palpable abdominal mass which was revealed to be a primary omental tumor by means of UGI, small bowel series, abdominal ultrasonography, and computed tomography. Upon laparotomy, no metastatic focus was found and a part of tumor was found adhered to gastric serosa. Total omentectomy including the mass was performed. Histological examinations of the tumor confirmed a diagnosis of leiomyosarcoma. At 36 months postoperatively, there is no sign of tumor recurrence or metastasis.
Aged ; Diagnosis ; Female ; Humans ; Laparotomy ; Leiomyosarcoma* ; Neoplasm Metastasis ; Omentum ; Recurrence ; Serous Membrane ; Ultrasonography

BACKGROUND: Alcoholic liver disease has increased. The causes of death in liver cirrhosis have changed. The author tried to categorize the etiology and complications of liver cirrhosis and analyze the causes of death in the 1990s. METHOD: The author retrospectively reviewed medical records of 1,175 patients diagnosed as having liver cirrhosis at Kyung Hee University Hospital from January 1991 through December 1998. The etiology, complications and the cause of death were compared between the early (1991-1994) and the late (1995-1998) periods. RESULTS: The proportion of male patients (73.3%) was still about 3 times that of female patients. There was no difference in age at the time of diagnosis between early and late periods (51.4 11.1 and 51.2 11.2 years respectively). Hepatitis B virus (HBV) infection was still the most common cause of liver cirrhosis (57.0%) and alcohol was the next (31.1%). The complications of liver cirrhosis at the time of diagnosis were, in order: esophageal varices, ascites, and variceal bleeding. But there was no significant difference between the periods. The proportion of Child grade B was the most common at the time of diagnosis in both periods, but Child grade A increased in the late period. The most common cause of death was liver failure and the next cause was variceal bleeding in the early period. Hepatorenal syndrome was the second most common cause in the late period. CONCLUSION: There was no change in the etiology between early and late periods. HBV infection was still the most common etiology but the incidence of alcoholic liver cirrhosis might have increased in the 1990s. The proportion of the Child B at initial diagnosis was the highest (around 50%) but that of Child A increased in the late period. Among the causes of death, liver failure and hepatorenal syndrome had a tendency to increase in the late period.
Ascites ; Cause of Death* ; Child ; Diagnosis ; Epidemiology ; Esophageal and Gastric Varices ; Female ; Hepatitis B virus ; Hepatorenal Syndrome ; Humans ; Incidence ; Liver Cirrhosis* ; Liver Cirrhosis, Alcoholic ; Liver Diseases, Alcoholic ; Liver Failure ; Liver* ; Male ; Medical Records ; Retrospective Studies

BACKGROUND/AIMS: Colonoscopic polypectomy is an effective tool for the treatment of colonic polyps. With the recent widespread use of colonoscopic polypectomy, there is a growing concern about iatrogenic complications, such as bleeding and perforation. The aim of this study is to analyze the clinical presentation and management of complications during colonoscopic polypectomy. METHODS: We retrospectively reviewed the medical records of colonoscopic examinations performed at 5 hospitals of Hallym University Medical Center between June 2005 and June 2008. RESULTS: A total of 26,773 colonoscopies and 4,123 colonoscopic polypectomy were performed. The overall rate of complication was 1.04% (43/4,123). Perforation occurred in 0.19% (8/4,123) of cases, and bleeding occurred in 0.85% (35/4,123) of cases. Perforation occurred in 0.05% of snare polypectomies, 1.09% of endoscopic mucosal resections (EMR), and 7.14% of endoscopic submucosal dissections (ESD). Bleeding occurred in 0.8% of snare polypectomies, 1.09% of EMRs, and 3.57% of ESDs. The complication rate of ESDs was higher than in EMRs and snare polypectomies (P<0.001). Endoscopic clippings were performed in 25% of perforation and 66.7% of bleeding cases. Medical treatment was successful in 75% of perforation and 100% of bleeding cases. CONCLUSIONS: Colonoscopic polypectomy is a safe procedure for the treatment of colonic polyps, but rarely, serious complications occur. Compared to a snare polypectomy or an EMR, the complication of an ESD occurs more frequently. Endoscopic treatment and further conservative management seems to be appropriate in most cases with complication.
Academic Medical Centers ; Colonic Polyps ; Colonoscopy ; Hemorrhage ; Medical Records ; Retrospective Studies ; SNARE Proteins