• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7719-7724
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• 2014

Background: Lymph node metastasis is believed to be a dependent negative prognostic factor of esophageal cancer. To explore detection methods with high sensitivity and accuracy for metastases to regional and distant lymph nodes in the clinic is of great significance. This study focused on clinical application of FDG PET/CT and contrast-enhanced multiple-slice helical computed tomography (MSCT) in lymph node staging of esophageal cancer. Materials and Methods: One hundred and fifteen cases were examined with enhanced 64-slice-MSCT scan, and FDG PET/CT imaging was conducted for neck, chest and upper abdomen within one week. The primary lesion, location and numbers of metastatic lymph nodes were observed. Surgery was performed within one week after FDG PET/CT detection. All resected lesions were confirmed histopathologically as the gold standard. Comparative analysis of the sensitivity, specificity, and accuracy based on FDG PET/CT and MSCT was conducted. Results: There were 946 lymph node groups resected during surgery from 115 patients, and 221 were confirmed to have metastasis pathologically. The sensitivity, specificity, accuracy of FDG PET/CT in detecting lymph node metastasis were 74.7%, 97.2% and 92.0%, while with MSCT they were 64.7%, 96.4%, and 89.0%, respectively. A significance difference was observed in sensitivity (p=0.030), but not the others (p>0.05). The accuracy of FDG PET/CT in detecting regional lymph node with or without metastasis were 91.9%, as compared to 89.4% for MSCT, while FDG PET/CT and MSCT values for detecting distant lymph node with or without metastasis were 94.4% and 94.7%. No significant difference was observed for either regional or distant lymph node metastasis. Additionally, for detecting para-esophageal lymph nodes metastasis, the sensitivity of FDG PET/CT was 72%, compared with 54.7% for MSCT (p=0.029). Conclusions: FDG PET/CT is more sensitive than MSCT in detecting lymph node metastasis, especially for para-esophageal lymph nodes in esophageal cancer cases, although no significant difference was observed between FDG PET/CT and MSCT in detecting both regional and distant lymph node metastasis. However, enhanced MSCT was found to be of great value in distinguishing false negative metastatic lymph nodes from FDG PET/CT. The combination of FDG PET/CT with MSCT should improve the accuracy in lymph node metastasis staging of esophageal cancer.

• 한국임상수의학회지
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• 제33권3호
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• pp.168-171
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• 2016

Signalment: An 8-month-old female Alaskan malamute was presented for progressive cluster seizure disorder. Results: There were no abnormalities on neurological examination, survey radiographs, or blood analysis. Magnetic resonance (MR) imaging and computed tomography revealed extension of the olfactory bulb and frontal lobe into the nasal cavity. They also confirmed abnormal anatomy of the nasal turbinates within the rostral part of the nasal cavity and the absence of a cribriform plate. On T2-weighted and fluid-attenuated inversion recovery images, the herniated brain showed heterogeneous and hyperintense signals consistent with intraparenchymal edema. Transverse MR images showed brain herniation into the right frontal cavity and an asymmetrical lateral ventricle because of a left midline shift. On contrast-enhanced MR images, the protruding brain parenchyma was mildly enhanced. Ethmoidal encephalocele was suspected as the final diagnosis. Despite symptomatic treatment, the dog continued to exhibit seizures and was euthanized. Clinical relevance: Ethmoidal encephalocele is a rare disease in dogs. However, it could be considered as a cause of seizure in young dogs.

• Imaging Science in Dentistry
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• 제35권2호
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• pp.111-114
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• 2005

A 15-year-old patient, who had been diagnosed and treated as Burkitt cell type acute lymphoblastic leukemia (ALL-L3) already, visited our department. He complained of gingival enlargement and loosening teeth 1 month ago. The clinical examination revealed anterior open bite, gingival enlargement, and nontender swelling particularly in molar regions of both jaws. Deep periodontal pockets and severe mobility was shown on most of the teeth. The panoramic radiographs showed severe bone destruction and extrusion of the molars. The contrast enhanced CT showed multiple enhanced mass and bone marrow obliteration in both jaws. Chemotherapy was done and the swelling was subsided at 1 month later. In conclusion, radiologic findings of leukemia with soft tissue mass, known as chloroma or granulocytic sarcoma, mimic those of lymphoma, so blood test may be needed for the final diagnosis.

• Journal of Trauma and Injury
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• 제21권1호
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• pp.28-35
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• 2008

Purpose: This study was conducted to examine the clinical significance IV-contrasted helical abdomen computed tomography (CT) as a diagnostic screening tool to evaluate hollow viscus injury in blunt abdominal trauma patients. Methods: This is a retrospective study encompassing 108 patients, presenting to Korea University Medical Center (KUMC) Emergency Department (ED) from January 2007 to December 2007, with an initial CT finding suggestive of intra-abdominal injury. An initial non-enhanced abdomen CT was taken, followed by an enhanced CT with intravenous contrast. Patients' demographic data, as well as the mechanisms of injury, were inquired upon and obtained, initial diagnosis, as dictated by specialized radiologists, were added to post-operational (post-OP) findings and to additional CT findings acquired during their hospital stays, and all were combined to arrive at final diagnosis. Initial CT findings were further compared with the final diagnosis, yielding values for sensitivity, specificity, and accuracy, as well as positive and negative predictive values. Patients were further divided into two groups, namely, those that underwent operational intervention and those that did not. The initial CT findings of each group were subsequently compared and analyzed. Results: Initial CT scans revealed abnormal findings in a total of 212 cases - solid organ injuries being the most common finding, as was observed in 97 cases. Free fluid accumulation was evident in another 69 cases. Based on the CT findings, 77 cases (71.3%) were initially diagnosed as having a solid organ injury, 20 cases (18.5%) as having a combined (solid organ + hollow viscus) injury, and 11 cases (10.2%), as having an isolated hollow viscus injury. The final diagnosis however, were somewhat different, with only 67 cases (62.0%) attributed to solid organ injury, 31 cases (28.7%) to combined injury (solid + hollow), and 10 cases (9.3%) to hollow viscus injury. The sensitivity (CI 95%) of the initial helical CT in diagnosing hollow viscus injury was 75.6%, and its specificity was 100%. The accuracy in diagnosing hollow viscus injury was also meaningfully lower compared to that in diagnosis of solid organ injury. Among patients initially diagnosed with solid organ injuries, 10 patients (2 from follow-up CT and 8 from post-OP finding) turned out to have combined injuries. A total of 38 patients underwent an operation, and the proportion of initial CT findings suggesting free air, mesenteric hematoma or bowel wall thickening turned out to be significantly higher in the operation group. Conclusion: Abdominal CT was a meaningful screening test for hollow viscus injury, but the sensitivity of abdominal CT was significantly lower in detecting hollow viscus injury as compared to solid organ injury. This calls for special consideration and careful observation by the ED physicians when dealing with cases of blunt abdominal trauma.

• 대한영상의학회지
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• 제79권6호
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• pp.303-310
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• 2018

목적: 이 연구의 목적은 흉부 전산화단층촬영(CT)에서 우연히 발견된 유방 병변의 임상적 중요성을 평가하고 유방 전문 진료 의뢰가 필요한 영상 소견을 제안하는 것이다. 대상과 방법: 2009년 5월부터 2014년 4월까지 촬영된 조영증강 흉부 CT 중에서 판독문에 '유방'이라는 단어가 포함된 검사를 후향적으로 검토하였다. 이 중 우연히 발견된 유방 병변으로 유방 초음파와 유방 촬영술을 한 뒤, 병리학적 확인이나 1년 이상의 추적 관찰을 받은 총 86명의 환자(모두 여성, 평균 연령, $48.9{\pm}12.6$세)를 대상으로 하였다. 흉부 CT에서 유방 병변의 크기, 위치, 모양, 경계 및 조영 증강을 포함한 영상 특징을 평가하였다. 다양한 CT 특징과 병리소견과의 연관성을 평가하고 여러 조합의 CT 특징의 진단 정확도를 평가하였다. 결과: 흉부 CT에서 우연히 발견된 유방 병변 중 악성 종양은 16.3%(14/86)였다. 악성 병변은 양성 병변에 비해 불규칙한 모양, 불분명한 경계, 높은 조영증강을 보였다. CT 특징의 조합 중 불분명한 경계와 높은 조영증강의 조합이 악성 병변을 예측하는데 가장 높은 정확도를 보였다(97.7%). 결론: 흉부 CT에서 우연히 발견된 유방 병변의 16.3%는 악성이었으며, 불분명한 경계와 높은 조영증강을 동시에 보일 경우 악성 가능성이 높으므로, 정확한 진단을 위해 유방 전문 진료 의뢰가 필요하다.

• 대한영상의학회지
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• 제82권6호
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• pp.1477-1492
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• 2021

목적 Dedicated breast CT (이하 DBCT)는 유방 압박의 고통이 없는 영상 진단 기법으로 최근 주목받고 있다. 본 연구에서는 DBCT 영상에서 약하게 조영증강된 작은 병변의 검출률을 높이기 위해 피사체의 기하학적 정보를 이용하여 최적의 영상 문턱값을 제공하는 adaptive image rescaling (이하 AIR) 기법을 제안하였다. 대상과 방법 5개의 동일 크기의 구멍과 서로 다른 크기의 구멍을 가지는 두 개의 디스크를 각각 제작하고, 이를 60 kVp와 100 kVp로 스캔하여 single-energy CT (이하 SECT), dual-energy CT (이하 DECT), 그리고 AIR 영상을 생성하였다. 전임상 평가를 위해 돼지 조직 영상도 획득하였다. Image contrast (이하 IC)와 contrast-to-noise ratio (이하 CNR)로 화질을 평가하였으며, student's t test를 이용하여 영상 간 화질의 차이를 검증하였다. 결과 AIR의 평균 IC (0.70)는 DECT (0.94)의 74.5%로 나타났으며, SECT (0.22) 보다 318.2% 높았다. 또한 AIR의 평균 CNR (5.08)은 SECT (14.30)의 35.5%로 나타났고 DECT (2.28) 보다 222.8% 높게 측정되었다. 돼지 조직의 전임상 평가 결과도 비슷한 양상을 보였다. 결론 AIR은 SECT보다 높은 영상 대조도를 가지며, 50% 선량만으로도 DECT에 비견할 만한 화질 성능을 제공할 수 있음을 확인하였다. 따라서 AIR은 DBCT 영상에서 약하게 조영증강된 병변의 검출률을 개선할 수 있을 것으로 생각된다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제15권2호
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• pp.102-110
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• 2015

The main source of noise in computed tomography (CT) images is a quantum noise, which results from statistical fluctuations of X-ray quanta reaching the detector. This paper proposes a neural network (NN) based hybrid filter for removing quantum noise. The proposed filter consists of bilateral filters (BFs), a single or multiple neural edge enhancer(s) (NEE), and a neural filter (NF) to combine them. The BFs take into account the difference in value from the neighbors, to preserve edges while smoothing. The NEE is used to clearly enhance the desired edges from noisy images. The NF acts like a fusion operator, and attempts to construct an enhanced output image. Several measurements are used to evaluate the image quality, like the root mean square error (RMSE), the improvement in signal to noise ratio (ISNR), the standard deviation ratio (MSR), and the contrast to noise ratio (CNR). Also, the modulation transfer function (MTF) is used as a means of determining how well the edge structure is preserved. In terms of all those measurements and means, the proposed filter shows better performance than the guided filter, and the nonlocal means (NLM) filter. In addition, there is no severe restriction to select the number of inputs for the fusion operator differently from the neuro-fuzzy system. Therefore, without concerning too much about the filter selection for fusion, one could apply the proposed hybrid filter to various images with different modalities, once the corresponding noise characteristics are explored.

• 한국임상수의학회지
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• 제23권3호
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• pp.355-360
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• 2006

Four dogs with similar respiratory signs were referred to Veterinary Medical Teaching Hospital, Seoul National University. The clinical signs observed in these cases were anorexia, nasal discharge, sneezing, epistaxis, ocular discharge, and exophthalmoses. The routine laboratory tests revealed leukocytosis in two cases. On the skull radiographs, soft tissue density filled nasal cavity with loss of turbinate detail and increased density in frontal sinuses were found in all cases. Lysis of nasal bone was seen in two cases. Lysis of zygomatic arch was seen in one case. On computed tomography scan images, asymmetrical destruction of turbinate and nasal septum, and the superimposition of a soft tissue mass over the turbinate with peripheral contrast enhanced effect were identified in all cases. Destruction of ipsilateral orbital bone and invasion to retrobulbar region were visualized in all cases. In addition, all cases had lysis of cribriform plate. Lysis of nasal bone and destruction of hard palate were seen in two cases. Swelling of submandibular lymph node and salivary gland was seen in a case. Invasion to brain was identified in a case. All cases were diagnosed as nasal adenocarcinoma by cytology with fine needle aspiration and curettage.

• Journal of Yeungnam Medical Science
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• 제30권2호
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• pp.105-108
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• 2013

Type 1 neurofibromatosis (von Recklinghausen's disease, NF-1) is an autosomal-dominant neurocutaneous-disorder characterized by systemic cafe'-au-lait spots, multiple cutaneous neurofibromas, axillary or inguinal freckling, and Lisch nodules (pigmented iris hamartomas). Approximately 10-25% of NF1 patients have gastrointestinal neoplasms. Gastrointestinal stromal tumor (GIST) in patients with neurofibromatosis is most commonly found in the small bowel and the stomach, and approximately 60% of such patients have multiple tumors or multiple tumor sites. Although, the increased incidence of GIST in patients with neurofibromatosis is well documented in pathology literature in English, but has rarely been documented in Korea. Here, we report a case of multiple GISTs in a 48-year-old woman accompanied by NF1. She was admitted to Yeung-nam University Hospital with complaints of melena and dyspnea. A contrast-enhanced computed tomography (CT) scan revealed that multiple soft tissue masses were occupying the entire peritoneal cavity. An ultrasonogram- guided biopsy was performed and the tumors were found to have been composed of tumor cells that were positive for c-kit protein. The patient was put on Imatinib mesylate treatment, and further follow-up will be carried out.

• Journal of Yeungnam Medical Science
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• 제32권1호
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• pp.26-30
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• 2015

Sarcoidosis is a systemic disease of unknown cause involving multiple organs and is characterized by noncaseating granuloma. Immune thrombocytopenia (ITP) is an autoimmune disease characterized by increased peripheral platelet destruction due to the presence of an antibody to the platelet and abnormal platelet production. There is no known pathogenesis that occurs concurrently with ITP and sarcoidosis. However, considering together of 2 known pathogenesis, abnormal immune response triggers either ITP or sarcoidosis. The disease that develops first stimulates secondary disease. After development of secondary disease, they stimulate each other. A few cases of ITP associated with sarcoidosis are well documented in English; however, the disease has rarely been reported in Korea. Here, we report on a case of ITP with sarcoidosis in a 29-year-old man. He suffered from easy bruising. The chest X-ray and the contrast-enhanced computed tomography scan showed bihilar lymphadenopathy and reticulonodular infiltrates. Bone marrow study and fluoroscopy-guided percutaneous needle biopsy were performed and the patient was diagnosed with sarcoidosis and ITP. He was put on 400 mg/kg of intravenous immunoglobulin for 5 days and administered oral steroids and further follow-up will be carried out. He has shown a good response without significant bleeding event. However, administration of more oral steroid and additional follow-up is required than for single disease, whether sarcoidosis or ITP.