• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.703-706
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• 2004

나선형 CT 혈관촬영에서 획득한 영상의 분석를 통해서 폐색전증이 의심되는 부위를 자동으로 검출하는 방법으로, 연구 대상은 20명의 환자를 대상으로 분석하였으며 CT 검사 후 방사선과 의사가 정상소견을 받은 환자 5명과 폐색전증이 있는 판독소견을 가진 15명을 대상으로 비교 분석하였다. CT 검사하는 동안에 조영제를 투입하면, 폐색전증이 발생한 부위는 조영제 양과 분포가 불균등하여 명암값이 낮게 검출된다. 검출방법으로는 전처리 작업으로 폐영역만을 분할하고, 분할된 폐영역에서 혈관을 찾기 위해 모폴로지기법를 적용하여 세선화(thinning) 작업을 진행한다. 다음 공정으로는 경계선을 찾아 local watershed를 적용하여 혈관을 검출하고, 검출된 혈관내에서 원형모델을 적용하여 모폴로지(morphology)을 통해 국소 부위의 미세한 농도변화를 인지하여 색전이 발생한 영역을 자동검출하였다. 본 논문의 자동검출시스템에서는 색전증이 있는 경우에 true positive의 발생빈도는 case 당 4.5개가 검출되었다. 정상인의 경우에도 혈류의 흐름, 혈류의 분기점, 노이즈로 인한 false positive의 빈도는 case 당 2.6개가 발생하여 전체적으로 false positive는 5.2개가 검출되었다. 본 논문은 false positive의 비율이 높게 검출되었지만 폐영역 CT 검사의 컴퓨터지원진단시스템(computer aided diagnosis)의 향후 연구과제에 방향을 제시할 수 있을 것이라 사료된다.

• Journal of the Korean Society of Radiology
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• v.81 no.3
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• pp.688-700
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• 2020

Purpose To compare the incidence, survival rate, and CT findings of acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) between patients with and without lung cancer. Materials and Methods From June 2004 to July 2018, 89 consecutive patients diagnosed with IPF were included. Among them, 26 patients had IPF with lung cancer (IPF-LCA), and 63 patients had IPF alone. The clinical characteristics and CT findings associated with IPF, lung cancer, and AE were reviewed. Surgery and chemotherapy were performed for 6 and 23 cases of lung cancer, respectively, as the first- or second-line anticancer treatment. The overall survival, CT findings, disease-free period before AE, and duration from the onset of AE to death were compared. Results The incidence of AE was 61.5% in the IPF-LCA group and 58.7% in the IPF group (p = 0.806). The mean overall survival in the IPF-LCA and IPF groups were 16.8 and 83.0 months, respectively (p < 0.001). The mean durations from the start of the lung cancer treatment to the onset of AE were 16.0 and 4.6 months in cases of surgical treatment and chemotherapy, respectively. In comparison of death from AE, the survival rate was significantly lower in the IPF-LCA group than in the IPF group (p = 0.008). In the CT findings associated with AE, the IPF-LCA group tended to have a peribronchial (p < 0.001) or asymmetric distribution (p = 0.016). Conclusion In patients with IPF who develop lung cancer, the rate of death from AE is higher than that in patients with IPF alone. They tend to have unusual CT patterns associated with AE, such as a peribronchial or asymmetric distribution.

• Journal of Gastric Cancer
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• v.6 no.4
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• pp.291-294
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• 2006

F-18 FDG-PET/CT could be used to evaluate the surveillance of recurrent stomach cancer, but some cases reported as false-positives. The authors found an activated charcoal granuloma from intraperitoneal chemotherapy by using a curative resection and mitomycin C for stomach cancer. A mass behind the right colon that showed on CT 6 months after an operation in a 46-year-old male patient had no progression in size, but 36 months after the operation, an increase was seen on F-18 FDG-PET/CT, and a metastatic tumor was suspected. The tumor was resected by an explorative laparotomy and was diagnosed as being an activated charcoal granuloma based on the histologic finding. Based on this case, we should be reminded of the possibility of a false-positive on analysis of F-18 FDG-PET/CT caused by an activated charcoal granuloma in a patient who has intraperitoneal chemotherapy.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.226-232
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• 2009

Background: Blunt chest trauma accounts for 90% of all chest traumas in Europe and the United States and this causes 20% of all trauma-related deaths. The major cause of morbidity and mortality after blunt chest trauma is undetected injuries. For this reason, chest computerized tomography has gained popularity for the evaluation of trauma, but it is expensive and it exposes patients to radiation. This study identified the clinical features associated with the diagnosic information obtained on a CT chest scan, as compared with a standard chest X-ray, for patients who sustained blunt trauma to the chest. This study also evaluated the role of a routine computed tomographic (CT) scan for these patients. The patients who had chest computed tomography done after the initial chest x-ray were analyzed separately for the presence of occult injuries. Material and Method: We studied 100 consecutive patients from November 2006 to July 2007: 74 patients after motor vehicle crashes and 26 patients after a fall from a height >2m. Simultaneous with the initial clinical evaluation, an anteroposterior chest radiograph and a helical chest CT scan were obtained for all the patients. The data extracted from the medical record included the vital signs, the interventions and the type and severity of injury (RTS). Result: Among the 100 cases, 79 patients showed at least more than one pathologic sign on their chest radiograph, and 21 patients had a normal chest radiograph. For 17 of the patients who had a normal chest X ray, the CT scan showed multiple injuries, which were pneumothorax, hemothorax, lung contusion, sternal fracture etc. This represents that a CT scan is statistically superior to a chest radiograph to diagnose the pathologic signs. But on the other hand, as for treatment, only 31 patients were diagnosed by CT scan and they were treated with chest tube insertion ect. 42 patients needed ony conservative management without invasive thoracosurgical treatment such as chest tube insertion or open thoracotomy. 27 patients were treated based on the diagnosis made by the chest radiograph and physical examination. Conclusion: Chest computerized tomography was significantly more effective than routine chest X-ray for detecting lung contusion, pneumothorax and mediastinal hematoma, as well as fractured ribs, scapula and, sternum. Although the occult findings increased, the number of patients who needed treatment was small. Therefore, we suggest making selective use of a CT scan to avoid its overuse in ERs.

• The Korean Journal of Nuclear Medicine
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• v.32 no.2
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• pp.161-167
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• 1998

Purpose: Segmental parenchymal excretion delay on Tc-99m DISIDA scan is caused by intrahepatic bile duct obstruction. However, the diagnostic value for intrahepatic bile duct obstruction is unknown. We conducted this study to assess the positive predictive value of segmental excretion delay for the diagnosis of intrahepatic bile duct obstruction, and additional benefit over other noninvasive radiologic studies. Materials and Methods: The study population consisted of 43 patients (48 scans) who showed segmental parenchymal excretion delay on Tc-99m DISIDA scan. The results of abdominal CT or ultrasonography, which was done within 1 month of Tc-99m DISIDA scan, were compared with scintigraphic findings. Results: The etiology of segmental parenchymal excretion delay was determined by ERC or PTC in 31 scans, and follow-up studies in 13 scans. No causes were identified in 4 scans. The positive predictive value of segmental parenchymal excretion delay for intrahepatic bile ductobstruction was 92% (44/48). On the other hand, 13% (5/38) of CT and 28% (5/18) of ultrasonography were normal. In 18% (7138) of CT and 17% (3/18) of ultrasonography, only intraheipatic bile duct dilatation was noted without any diagnostic findings of intrahepatic bile duct obstruction. Conclusion: Segmental parenchymal excretion delay on Tc-99m DISIDA scan had a high positive predictive value for the diagnosis of intrahepatic bile duct obstruction. Tc-99m DISIDA scan may be useful for the diagnosis of intrahepatic bile duct obstruction, especially in patients with nondiagnostic CT or ultrasonography. The diagnostic usefulness need to be confirmed by further prospective studies.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.226-236
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• 1995

We studied to evaluate CT characteristics of bronchogenic cysts. We retrospectively evaluated CT of 11 patients with pathologically proved bronchogenic cyst. Precontrast and postcontrast CT scan was performed in all. We analyzed CT with viewpoints of location, size, attenuation on pre- and postcontrast scan, and calcification. Three of 11 bronchogenic cysts were intrapulmonary in location and eight were located in the mediastinum. Two of 3 intrapulmonary bronchogenic cysts were located in the right lower lobe, and the remaining one was left lower lobe. Intrapulmonary bronchogenic cysts ranged from 6cm to 12cm in diameter (average, 9.7 cm). On CT, intrapulmonary bronchogenic cysts appeared as thin-wall air cyst, homogenous water attenuation and soft tissue attenuation with air bubble respectively. Mediastinal bronchogenic cysts were located in posterior mediastinum(n=5), superior mediastinum(n=2), middle mediastinum(n=1) respectively. These cysts ranged in size from 3cm to 8cm in diameter (average, 5.0 cm). On CT, five showed homogenous water attenuation, two soft tissue attenuation similar to that of muscle, one air-fluid level. Calcification or contrast enhancement was not detected in any cases. On operative findings, all of intrapulmonary bronchogenic cysts contained dirty pus-like material and all of mediastinal bronchogenic cysts contained whitish or yellowish mucus material. Bronchogenic cysts showed homogenous water density in many cases, homogenous soft tissue density, air-fluid level and air-filled cyst. The constellation of CT findings may be helpful in the diagnosis and differentiation of bronchogenic cyst.

• Journal of Veterinary Clinics
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• v.30 no.5
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• pp.390-393
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• 2013

This case study describes the imaging features of radiography and computed tomography (CT) in four small breed dogs with lung lobe torsion. The medical records, thoracic radiographs and CT images of four dogs with confirmed lung lobe torsion were retrospectively reviewed. Pleural effusion and increased lobar opacity/density were seen on all CT and thoracic radiography in all four dogs. CT revealed narrowed/collapsed bronchus in all four dogs, while this was only appreciated on one thoracic radiography. The vesicular emphysema pattern was seen on four CT but only on three radiographic examinations. The specific findings of lung lobe torsion were vesicular emphysema and a narrowed/collapsed bronchus. These findings were more easily recognized on CT than with thoracic radiographs.

• Journal of the Korean Society of Radiology
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• v.82 no.4
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• pp.903-913
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• 2021

Purpose To identify the imaging features indicative of sarcoid-like reactions in patients with intrathoracic lymphadenopathy after complete remission of malignancies. Materials and Methods This study enrolled five patients with histopathologically confirmed sarcoid-like reactions that developed after cancer remission. The clinical features and findings of CT and ¹⁸F-fluorodeoxyglucose (FDG) PET/CT were assessed. Results The underlying malignancies included breast, nasopharyngeal, colon, and endometrial cancer and lymphoma. The time intervals between complete remission of malignancy and the diagnosis of sarcoid-like reaction ranged from 6 to 78 months. CT findings of sarcoid-like reaction included bilateral hilar and mediastinal lymphadenopathies (n = 5), pulmonary nodules (1-15 mm) with peribronchovascular, fissural, or subpleural distribution, and interlobular interstitial thickening in the lungs (n = 4). ¹⁸F-FDG PET/CT revealed hypermetabolic uptake in the mediastinal and hilar lymph nodes and both lungs in the absence of extrathoracic uptake (n = 3). The sarcoid-like reactions resolved in all patients after corticosteroid treatment. Conclusion In patients with complete remission of malignancies, newly developed bilateral hilar and mediastinal lymphadenopathies with or without pulmonary nodules of perilymphatic distribution, in the absence of recurrence at the primary tumor site and extrathoracic metastasis, may suggest a sarcoid-like reaction. Such cases warrant histologic evaluation of the lymph nodes to prevent unnecessary systemic chemotherapy.

• Radiation Oncology Journal
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• v.9 no.2
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• pp.271-276
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• 1991

A series of 510 patients with carcinoma of the uterine cervix given the curative radiation therapy from March 1979 through December 1986 was evaluated to determine the value of intravenous pyelography (IVP), cystoscopy, sigmoidoscopy, and abdomino-pelvic CT as staging work-up prior to treatment. On IVP and cystoscopy, $10.7\%$(49/456) and $5.3\%$(24/452) showed abnormality, respectively, but only $0.7\%$(3/413) did on sigmoidoscopy. As a result of these work-ups prerequisite to FIGO staging, twenty six ($5.1\%$) out of 510 patients were upstaged from the stage determined by the findings of physical examination alone. The proportions of upstaging in each stage were as follows; none in stage IB (35), IIA (89) and IIIA (8), $7.9\%$(20/252) in stage IIB (14 patients to FIGO stage IIIB, 6 patients to FIGO stage IVA), and $4.8\%$(6/126) in stage IIIB (all to FIGO stage IVA). Positive findings of staging work-ups were found only in patients with advanced stages of stage IIB or over determined by physical examination alone but not in those with earlier stages. CT was performed in 337 patients. CT detected pelvic lymph node (LN) enlargement in $25.2\%$ (85/337) and paraaortic LN enlargement in $7.4\%$(25/337). Pelvic LN positivity was well correlated with increasing stage but paraaortic LN positivity was not. In the evaluation of parametrial involvement, CT findings were in accordance with those of physical examination only in $65.6\%$ (442/674). When compared with endoscopic studeies, CT had much lower positive predictive value than negative predicitive value in the evaluation of adjacent organ invasion. The staging work-ups should be individualized by the disease extent of each patient, and then the efficiency of work-uus may be increased without compromising the appropriate FIGO staging and treatment.

• Journal of Chest Surgery
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• v.43 no.6
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• pp.675-680
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• 2010

Background: The aim of this study was to identify the distinguishing clinicoradiologic findings of traumatic tracheobronchial injury. Material and Method: Between January 2003 and December 2009, six patients who underwent surgical repair for traumatic tracheobronchial injury due to blunt trauma were included in this study. We evaluated the mechanism of the injury, the coexisting injuries, the time until the making diagnosis and treatment, the diagnostic methods, the anatomic location of the injury and the surgical outcomes. Result: The mechanisms of injury were traffic accident and crushing forces. The frequent symptoms were subcutaneous emphysema, dyspnea and pain, and the common radiologic findings were pneumothorax, mediastinal emphysema, rib fracture and lung contusion. Only 2 patients were diagnosed by chest CT and the others were not diagnosed preoperatively. The location of injury was the trachea in 2 patients and the bronchial tree in 4 patients. There was no postoperative mortality or anastomotic leak; however, vocal cord palsy occurred in one patient. The most distinguishing sign was persistent lung collapse even though the chest tube was connected with negative pressure. Conclusion: Although it was not easy to diagnose traumatic tracheobronchial injury without a clinical suspicion, the distinguishing clinical symptoms and CT findings could help to make an early diagnosis without performing bronchoscopy.