PURPOSE: To determine the accuracy of automated computer aided volumetry for simulated small pulmonary nodules at computed tomography using various types of phantoms MATERIALS AND METHODS: Three sets of synthetic nodules (small, calcified and those adjacent to vessels) were studied. The volume of the nodules in each set was already known, and using multi-slice CT, volumetric data for each nodule was acquired from the three-dimensional reconstructed image. The volume was calculated by applying three different threshold values using Rapidia(R) software (3D-Med, Seoul, Korea). RESULTS: Relative errors in the measured volume of synthetic pulmonary nodules were 17.3, 2.9, and 11.5% at -200, -400, and -600 HU, respectively, and there was good correlation between true volume and measured volume at -400 HU (r=0.96, p<0.001). For calcified nodules, relative errors in measured volume were 10.9, 5.3, and 16.5% at -200, -400, and -600 HU, respectively, and there was good correlation between true volume and measured volume at -400 HU (r=1.03, p<0.001). In cases involving synthetic nodules adjacent to vessels, relative errors were 4.6, 16.3, and 31.2 % at -200, -400, and -600 HU, respectively. There was good correlation between true volume and measured volume at -200 HU (r=1.1, p<0.001). CONCLUSION: Using computer-aided volumetry, the measured volumes of synthetic nodules correlated closely with their true volume. Measured volumes were the same at each threshold level, regardless of window setting.
Cone-Beam Computed Tomography ; Seoul

On page 545, the fifth author's name has been incorrectly spelled as Jin Mo Koo. The correct spelling is Jin Mo Goo.

Patent ductus arteriosus(PDA) is a common congenital heart disease encountered in premature neonates infants and children. Patent ductus arteriosus was the first surgically managed congenital heart disease,. Classic surgical interruption of patent ducturs arteriosus was partially replaced by a transcatheter endovascular closure, After a 5-7 mm video-assisted thoracoscopic interruption of the patent ductus arteriosus first applied in 1991, this minimally invasive technique came to be used in many centers, Video-assisted thoracoscopic interruption of the patent ductus arteriosus is feasible in low-weight infants whereas transcatheter endovascular closure of the ductus is usually not possible. We experienced successful outcome for the treatment of patent ductus arteriosus with 2 mm video-assisted thoracoscopic titanium clipping, We believed that this technique is a simple safe and rapid method for closure of the patent arteriosus.
Child ; Ductus Arteriosus, Patent ; Heart Defects, Congenital ; Humans ; Infant ; Infant, Newborn ; Thoracoscopes* ; Thoracoscopy ; Titanium

No abstract available.
Child* ; Hearing Loss, Sensorineural* ; Humans ; Temporal Bone*

PURPOSE:To investigate the changes of abnormal signal intensity of liver infarction in scheduled intervals after ligation of portal vein in rabbit livers with histopathologic correlation. MATERIALS AND METHODS:Liver infarction were induced by selective ligation of the posterior branch of right portal vein in 12 rabbits. T1- and T2-weighted MRI at 2.0T with spin-echo techniques as well as contrastenhanced Tl-weighted MRI with Gd-DTPA(0.1 mmol/kg) were performed 3 hours, 6 hours, 1 day, 3 days, 1 week, and 2 weeks after ligation using two rabbits at each interval. Histopathologic specimens were prepared from six removed livers for comparing the MR findings with the histopathologic findings. The other six rabbits were sectioned transversely in frozen state for comparing MR findings with the macroscopic findings of pathologic areas of the liver. RESULTS: The signal intensity of pathologic hepatic segment showed more hyperintense signal than that of normal segments of the liver on TI-, proton density-, and T2-weighted MR images at every interval after ligation, except both T2WI of 3 hours interval and one T1WI of 2 weeks interval. Main histopathologic findings 3 hours, 6 hours, 1 day, 3 days, and 1 week after ligation were congestion, hemorrhage with necrosis, coagulation necrosis, complete necrosis, and necrosis with scar tissues, respectively. Microscopic specimens with Prussian blue stain 6 hours, and 1 week after ligation showed bluish hue indicating the existence of methemoglobin, and blue particles in giant cells and monocytes indicating engulfing hemosiderin, respectively. CONCLUSION: Changes of the signal intensities on sequential MR images of acutely induced hemorrhagic liver infarction might be due to the rapid oxidative denaturation of hemoglobin in hemorrhages and high signal intensity on Tl-weighted images from the hyperacute stage of a hemorrhagic liver infarction could be due to methemoglobin. Therefore, acutely induced hemorrhagic liver infarction should be included in the differential diagnoses of the hyperintense liver lesions on Tl-weighted images.
Cicatrix ; Diagnosis, Differential ; Estrogens, Conjugated (USP) ; Giant Cells ; Hemorrhage ; Hemosiderin ; Infarction ; Ligation* ; Liver* ; Magnetic Resonance Imaging* ; Methemoglobin ; Monocytes ; Necrosis ; Portal Vein* ; Protons ; Rabbits*

Sternal fractures, once thought of as an uncommon phenomenon, have occurred with an increasing frequency, paralleling the incidence of motor vehicle accidents. The tremendous force necessary to cause sternal fracture and this bone's prominent position overlying major intrathoracic and mediastinal structures, have important implications in the assessment and treatment of patients. This evaluation is based on the review of 72 patients of traumatic sternal fracture treated at the Department of Thoracic and Cardiovascular Surgery, Seoul Adventist Hospital during the last 4 years from March 1993 to February 1997. The frequency was 12.2% of nonpenetrating chest trauma and average age was 43.2 years old. Automobile accidents (84%) and sternal body fractures (95.8%) with anterior displacements (19.4%) was the most common cause and fracture site. Increase of cardiac isoenzymes was more frequent and higher in sternal fracture than chest contusion but there was no relationship between the time to take normalization of them and the mode of trauma.
Automobiles ; Contusions ; Humans ; Incidence ; Isoenzymes ; Motor Vehicles ; Seoul ; Thorax

PURPOSE: The purpose of our study was to compare the diagnostic value of contrast-enhanced spiral CT scanning and pulmonary angiography in detecting central and peripheral pulmonary embolism (PE) in pigs. MATERIALS AND METHODS: Experiments were performed in a porcine model of acute pulmonary embolism. Five pigs underwent contrast-enhanced spiral CT and pulmonary angiography after central venous administration of embolic material (Konyak). Three thoracic radiologists read the films and the results were compared with the findings of pathologic specimens. RESULTS: Of 85 cases of PE detected pathologically, 78 (91.8 %) were visible with spiral CT and 65 (76.5 %) with pulmonary angiography. Sensitivity and specificity for the detection of central emboli were 95 % and 100 %, respectively, with spiral CT, and 89 % and 100 %, respectively, with pulmonary angiography. Sensitivity and specificity for the detection of peripheral emboli were 88 % and 99 %, respectively, with spiral CT, and 64% and 100 %, respectively, with pulmonary angiography. CONCLUSION: Contrast-enhanced spiral CT is a very useful method for the diagnosis of both peripheral and central pulmonary embolism. Compared to pulmonary angiography its sensitivity and specificity are high.
Angiography ; Diagnosis ; Pulmonary Embolism* ; Sensitivity and Specificity ; Swine ; Tomography, Spiral Computed*

PURPOSE: The purpose of our study was to compare the diagnostic value of contrast-enhanced spiral CT scanning and pulmonary angiography in detecting central and peripheral pulmonary embolism (PE) in pigs. MATERIALS AND METHODS: Experiments were performed in a porcine model of acute pulmonary embolism. Five pigs underwent contrast-enhanced spiral CT and pulmonary angiography after central venous administration of embolic material (Konyak). Three thoracic radiologists read the films and the results were compared with the findings of pathologic specimens. RESULTS: Of 85 cases of PE detected pathologically, 78 (91.8 %) were visible with spiral CT and 65 (76.5 %) with pulmonary angiography. Sensitivity and specificity for the detection of central emboli were 95 % and 100 %, respectively, with spiral CT, and 89 % and 100 %, respectively, with pulmonary angiography. Sensitivity and specificity for the detection of peripheral emboli were 88 % and 99 %, respectively, with spiral CT, and 64% and 100 %, respectively, with pulmonary angiography. CONCLUSION: Contrast-enhanced spiral CT is a very useful method for the diagnosis of both peripheral and central pulmonary embolism. Compared to pulmonary angiography its sensitivity and specificity are high.
Angiography ; Diagnosis ; Pulmonary Embolism* ; Sensitivity and Specificity ; Swine ; Tomography, Spiral Computed*

OBJECTIVE: To determine the usefulness of a computer-aided diagnosis (CAD) system for the automated detection of lung nodules at low-dose CT. MATERIALS AND METHODS : A CAD system developed for detecting lung nodules was used to process the data provided by 50 consecutive low-dose CT scans. The results of an initial report, a second look review by two chest radiologists, and those obtained by the CAD system were compared, and by reviewing all of these, a gold standard was established. RESULTS : By applying the gold standard, a total of 52 nodules were identified (26 with a diameter < or =5 mm; 26 with a diameter > 5 mm). Compared to an initial report, four additional nodules were detected by the CAD system. Three of these, identified only at CAD, formed part of the data used to derive the gold standard. For the detection of nodules > 5 mm in diameter, sensitivity was 77% for the initial report, 88% for the second look review, and 65% for the CAD system. There were 8.0+/-5.2 false-positive CAD results per CT study. CONCLUSION : These preliminary results indicate that a CAD system may improve the detection of pulmonary nodules at low-dose CT.
Adult ; Aged ; Aged, 80 and over ; Diagnosis, Computer-Assisted/*methods/*standards ; Human ; Lung Neoplasms/classification/*radiography ; Mass Screening/methods ; Middle Aged ; Radiation Dosage ; Support, Non-U.S. Gov't ; Tomography, X-Ray Computed/*methods/*standards