• 한국방사선학회논문지
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• 제10권2호
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• pp.81-87
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• 2016

본 실험에서 제안된 질감특징분석 알고리즘은 지방간 환자의 CT영상을 이용하여 정상영상과 질환영상으로 구분하여, 정상 간 CT영상과 지방간 CT영상을 생성하고 제안된 질감특징분석을 이용한 컴퓨터보조 진단 시스템에 적용하여 6개의 파라메타로 정량적 분석을 통해 지방간 CT영상의 질환 인식률을 도출하고 평가하였다. 결과로 지방간 CT영상 30증례 중에서 각각의 파라메타별 질감특징 값에 대한 인식률은 평균 밝기의 경우 100%, 엔트로피의 경우 96.67%, 왜곡도의 경우 93.33%로 높게 나타났고, 평탄도의 경우 83.33%, 균일도의 경우 86.67%, 평균대조도의 경우 80%로 다소 낮은 질환 인식률을 보였다. 따라서 본 연구의 결과를 바탕으로 의료영상의 컴퓨터보조진단 시스템으로 발전된 프로그램을 구현한다면 지방간 CT영상의 질환부위 자동검출 및 정량적 진단이 가능해 컴퓨터보조진단 자료로서 활용이 가능할 것으로 판단되며 최종판독에서 객관성, 정확성, 판독시간 단축에 유용하게 사용 될 것으로 사료된다.

• Imaging Science in Dentistry
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• 제43권2호
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• pp.91-98
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• 2013

Purpose: This study was performed to identify correlations between keratocystic odontogenic tumor (KCOT) data from CT sections, and data on the KCOT clinical manifestation and resulting dental expenses. Materials and Methods: Following local Institutional Review Board (IRB) approval, a seven-years of retrospective study was performed regarding patients with KCOTs treated at the Seoul National University Dental Hospital. A total of 180 KCOT were included in this study. The following information was collected: age, gender, location and size of the lesion, radiological features, surgical treatment provided and dental expenses. Results: There was no significant association between the size of the KCOT and age, gender, and presenting preoperative symptoms. In both jaws, it was unusual to find KCOTs under 10 mm. The correlation between the number of teeth removed and the size of the KCOT in the tooth bearing area was statistically significant in the mandible, whereas in the maxilla, no significant relationship was found. Dental expenses compared with the size of the KCOT were found to be significant in both jaws. Conclusion: The size of KCOT was associated with a significant increase in dental expenses for both jaws and the number of teeth removed from the mandible. These findings emphasize the importance of routine examinations and early detection of lesions, which in turn helps preserving anatomical structures and reducing dental expenses.

• Tuberculosis and Respiratory Diseases
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• 제72권2호
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• pp.203-206
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• 2012

Cystic lesions or progressive cystic changes in adenocarcinoma of the lung have rarely been reported. We report a case of lung adenocarcinoma that progressed from ground-glass opacities (GGOs) and consolidations or nodules to extensive cystic lesions during 12 months in a young adult patient. A 29-year-old male was initially diagnosed with primary lung adenocarcinoma by transbronchial lung biopsy of the right lower lobe and lung to lung metastasis in both lungs according to imaging findings. The initial chest computed tomography (CT) scans showed multifocal GGOs, consolidations, and nodules in both lungs. Despite treatment with palliative chemotherapy, the patient's follow-up CT scans showed multiple, cystic changes in both lungs and that the lesions had progressed more extensively. He died of hypoxic respiratory failure one year after his diagnosis.

• Tuberculosis and Respiratory Diseases
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• 제70권2호
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• pp.150-154
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• 2011

We report a case of Caplan's Syndrome, which presented as multiple pulmonary nodules. A 58-year-old male was admitted to hospital due to multiple pulmonary nodules. In addition, the patient presented with multiple arthritis, and dyspnea on exertion. Rheumatoid arthritis had been diagnosed 35 years ago. The patient had worked as a stonemason for 20 years. Computed Tomography (CT) revealed numerous well-defined tiny nodules scattered in both lungs, which was suspicious of miliary tuberculosis or malignancy. The patient was started on antituberculous medications and referred to our hospital. First, a transbronchial lung biopsy was performed, which showed no evidence of granuloma. It was our opinion that the biopsy was insufficient, and a follow-up video-associated thoracoscopy was performed. The pathological report determined necrotizing granulomatous inflammation and silicosis on background. According to imaging studies, pathologic reports, and clinical symptoms, we concluded that the patient had Caplan's syndrome. We controlled his rheumatic medications, and instructed him to avoid exposure to hazardous dust.

• Radiation Oncology Journal
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• 제36권1호
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• pp.11-16
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• 2018

Purpose: To investigate interobserver variation in target volume delineations for prostate cancer salvage radiotherapy using planning computed tomography (CT) versus combined planning CT and magnetic resonance imaging (MRI). Materials and Methods: Ten radiation oncologists independently delineated a target volume on the planning CT scans of five cases with different pathological status after radical prostatectomy. Two weeks later, this was repeated with the addition of planning MRI. The volumes obtained with CT only and combined CT and MRI were compared, and the effect of the addition of planning MRI on interobserver variability was assessed. Results: There were large differences in clinical target volume (CTV) delineated by each observer, regardless of the addition of planning MRI ($9.44-139.27cm^3$ in CT only and $7.77-122.83cm^3$ in CT plus MRI) and no significant differences in the mean and standard deviation of CTV. However, there were decreases in mean volume and standard deviation as a result of using the planning MRI. Conclusion: This study showed substantial interobserver variation in target volume delineation for salvage radiotherapy. The combination of planning MRI with CT tended to decrease the target volume and the variation.

• Journal of Korean Neurosurgical Society
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• 제29권2호
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• pp.240-248
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• 2000

Objective : Spontaneous intracranial hypotension is a rarely reported syndrome of spontaneous postural headache associated with low CSF pressure and has rarely been demonstrated radiographically or surgically. But recently, it is being recognized with increasing frequency. The purpose of this study was to characterize clinical and imaging features, etiologic factors, and outcome in the spontaneous intracranial hypotension. Patients and Methods : We reviewed our experience with documented cases of spontaneous intracranial hypotension in 5 consecutive patients with orthostatic headaches from April 1998 to April 1999. Results : The mean age was 41 years(from 35 to 49 years). All patients had postural headaches, which were completely alleviated by recumbency position. Nausea, neck pain, horizontal diplopia, photophobia, and blurred vision were noted in some of the patients. Brain MRI showed diffuse pachymeningeal gadolinium enhancement, subdural collections of fluid, and descent of the brain. The opening pressure from lumbar puncture was $4cmH_2O$ or less in three of five patients whereas the opening pressure was within normal range in two patients. All patients underwent radioisotope cisternography and computerized tomographic myelography. On radioisotope cisternography, CSF leakage was suspected at the level of cervical area(1 patient), upper thoracic area(2 patients), mid-thoracic area(1 patient). Computed tomography myelography revealed extraarachnoid accumulation of contrast media(compatible finding with CSF leakage) at the level of cervical or thoracic area. In all patients, the symptoms resolved in response to supportive measures or epidural blood patch(1 patient). Conclusion : Spontaneous spinal CSF leakage is increasingly recognized as a cause of spinal postural headache. Most CSF leaks are located at the cervicothoracic junction or in the thoracic spine and can be demonstrated by variable diagnostic method. The condition is usually self-limiting and its prognosis is typically good.

• 한국정보과학회논문지:시스템및이론
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• 제31권3_4호
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• pp.224-238
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• 2004

다중 모달리티 영상정합은 서로 다른 성격의 두 영상의 중요정보를 결합하여 복합적 정보를 얻기 위해 널리 사용되는 영상처리 기법이다. 본 연구에서는 정합 대상 객체의 초기위치 및 방향에 종속적이지 않고, 낮은 정합오차 범위 내에서의 안정적인 정합을 지원하기 위하여 기존의 표면기반 정합 기법을 개선한 모멘트 정보 및 표면거리 기반의 정합 기법을 제시한다. 제안방법에서는 우선 정합대상객체의 표면 윤곽 점을 추출하고, 이를 기반으로 대상객체의 모멘트 정보를 추출하여, 표면거리 기반 상세 정합 이전에 모멘트 정보를 일치시키는 변환을 수행함으로써, 정합이전 대상객체의 위치 및 방향이 상이한 경우에 있어서도 정합이 안정적으로 수행되도록 한다. 또한 테스트 영상에 대한 표면 대표점 추출 시, 표면 코너추출법을 적용함으로써, 기존 표면 정보 기반 정합기법에서 일반적으로 사용하고 있는 무작위 샘플링 및 일정간격 샘플링에 의한 취약점을 보완한다. 본 논문에서 제안기법의 검증을 위하여 뇌 부위 자기공명단층영상(MRI)과 양자 방출 단층 촬영 영상(PET)을 적용하고, 정합오류율과 정합결과에 대한 2,3차원 가시화 영상의 육안평가를 통하여 정확성 및 안정성 측면을 검증한다.

• Journal of Chest Surgery
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• 제46권1호
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• pp.33-40
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• 2013

Background: Total arch replacement (TAR) is being more widely performed due to recent advances in operative techniques and cerebral protective strategies. In this study, the authors reviewed the relationship between TAR and early- and mid-term changes of the false lumen after TAR in acute type A aortic dissection. Materials and Methods: Twenty-six patients (aged, $54.7{\pm}13.3$ years) who underwent TAR for acute type A dissection between June 2004 and February 2012 were reviewed. The relationship between the percentage change in the aortic diameter and the false lumen patency status was assessed by examining the early and late postoperative computed tomography imaging studies. Results: There were two in-hospital mortalities, one late death, and three follow-up loses. The mean follow-up duration for the final 21 patients studied was $54{\pm}19.0$ months (range, 20 to 82 months). The incidence of false lumen thrombosis within 2 weeks of surgery in the proximal, middle, and distal thoracic aorta, and the suprarenal and infrarenal abdominal aorta were 67%, 38%, 38%, 48%, and 33%, respectively, and 57%, 67%, 52%, 33%, and 33% for those examined at a mean of $49{\pm}18$ months after surgery, respectively. The false lumen regressed in 11 patients (42.3%). The aortic diameters were larger in the patients with a patent false lumen than those with a thrombosed false lumen at all levels of the descending aorta (p <0.05). Conclusion: TAR and a more complete primary tear-resection can be accomplished with a relatively low-risk of morbidity and mortality. Enlargement of the distal aorta significantly correlated with the false lumen patency status.

• 한국산학기술학회논문지
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• 제18권8호
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• pp.84-87
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• 2017

뇌과관류증후군은 경동맥 스텐트 삽입술 또는 내막 절제술 시행 시 발생할 수 있는 드문 합병증으로 대사 요구량보다 관류가 더 많은 상태를 유발하는 다양한 기전에 의해 발생한다. 주 임상 증상은 편측성 두통, 고혈압, 발작 및 국소 신경계 결손이 있으며, 심한 경우 지주막하 출혈 및 뇌실질 출혈로 영구적 장애 또는 사망까지 유발할 수 있다. 일반적으로 뇌과관류증후군은 두개경유도플러, 관류 뇌자기공명영상 및 단일광자방출컴퓨터단층촬영으로 진단할 수 있다. 저자들의 연구에서는 내경동맥 스텐트 이후 확인한 혈관조영술에서 의미있는 정맥울혈 증상을 보여 뇌과관류증후군을 진단할 수 있었다. 환자는 증상성 양쪽 내경동맥 협착을 보이고 있었고, 협착으로 인해 곁순환 동맥들이 잘 발달하게 되었다. 이렇게 곁순환 동맥이 잘 발달된 상태에서 환자에게 내경동맥 스텐트를 삽입한 이후 대뇌 혈류량이 증가되며 혈류의 방향이 바뀌어 정맥 울혈이 생길 수 있으며, 경동맥 스텐트 삽입술 또는 내막 절제술 시행 이후 정맥울혈이 보일 시 뇌과관류증후군을 예측할 수 있다. 이 연구는 내경동맥 스텐트 삽입 후 바로 시행하는 혈관 조영술을 통해서 뇌과관류증후군을 확진할 수 있음을 보여준 1례의 보고이다.

• Journal of Yeungnam Medical Science
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• 제10권1호
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• pp.127-134
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• 1993

PTNB는 최근 CT 기술의 발전과 20 gauge 또는 22 gauge의 세침의 개발로 합병증을 줄이는 한편, 성공율이 높아 점차 임상적으로 널리 이용되는 추세에 있다. 이에 저자는 최근 44례의 PTNB를 분석하여 다음과 같은 결과를 얻었다. 환자의 분포는 50대 남자가 17례로 가장 많았고 종괴의 크기와 위치는 4cm 전후가 36례(84%)로 가장 많았다. 종괴의 국소적 위치는 변연부에 위치한것이 33례(75%)의 주로 폐의 변연부에 위치하였다. 조직 채취는 42례(95%)에서 가능했으며, PTNB의 민감도는 61%(27/44)였고 악성종괴와 양성종괴에 대한 민감도는 각각 79%(19/24), 44%(8/18)였다. 민감도가 비교적 낮은 이유는 단 1회 시술로 결과를 얻었고 민감도를 높이기 위한 반복 PTNB는 시행하지 않았기 때문으로 생각한다. 합병중인 기흉이나 각혈은 각각 1례에서 얻었고 모두 특별한 치료없이 호전되었다. 이상에서 PTNB는 다른 검사 방법 보다 간편하고 안전하며 기관지경을 통한 생검이 불가능하거나 생검후에도 병리소견을 못얻을 경우 PTNB를 통해 양성질환과 악성질환을 구분하므로서 환자의 치료 방침 결정에 도움을 줄 수 있을 것으로 사료되며, 국소적 폐 질환의 진단에 있어서 PTNB의 유용성은 더욱 증가하리라고 전망된다.