• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.04a
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• pp.255-260
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• 2005

위암은 국내 암발생 및 사망률의 상당 부분을 차지하고 있으며, 이러한 조기 위암의 발견은 치료 및 예후에 있어서 아주 중요하다. 본 논문에서는 조기 위암의 진단을 위해 위 내시경 영상에서 색상 변화를 이용해 이상 부위를 검출하여 검사자에게 조직적인 정보를 제공하는 시스템을 제안한다. 어느 정도의 진행이 이루어진 염증과 암은 쉽게 판단할 수 있지만, 조기의 염증이나 암의 경우에는 주의 깊게 보지 않는 경우에는 병변의 진단이 쉽지 않다. 본 논문에서는 위 내시경 영상을 IHB 채널로 변환시키고 조명에 의해 발생하는 잡음을 제거하며 자동으로 암 의심 영역을 검출하여 검사자에게 제공하거나 검사자에 의해 설정된 영역에 대한 조직적인 표면 정보를 제공한다. 본 논문의 연구는 추출된 이상 부위가 암을 확진할 수 없지만, 인간이 쉽게 인지하기 어려운 이상부위(암 의심 영역)를 추출하여 검사자에게 주의를 요구함으로써 일 처리를 줄이고 부과적인 정보를 제공한다. 그리고 검사추가 지정한 영역에 대해서도 조직적인 정보를 제공한다. 제안된 위 내시경 영상 분석 방법의 효율성을 확인하기 위해서 실제 내시경 영상들을 대상으로 실험한 결과, 제안된 방법이 위 내시경 영상 분석에 효율적임을 확인하였다.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.4
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• pp.473-478
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• 2005

The gastric cancer takes the great part of the cancer occurrence and the mortality from cancer in Korea, and the early detection of gastric cancer is very important in the treatment and convalescence. This paper. for the early detection of gastric cancer, Proposes the analysis system of endoscopic image of the stomach that detects the abnormal region by using the change of color in the image and provides the surface tissue information to the detector. While the advanced inflammation and the cancer may be easily detected, the early inflammation and the cancer have a difficulty in detection and require the more attention lot detection. This paper, at first, converts the endoscopic image to the Image of IHb(Index of Hemoglobin) model and removes noises incurred by illumination, and next, automatically detects the regions suspected as cancer and provides the related information to the detector, or provides the surface tissue information for the regions appointed by the detector. This paper does not intend to provide the final diagnosis of the detected abnormal regions as gastric cancer, but provides the supplementary mean that reduces the load and mistaken diagnosis of the detector by automatically detecting the abnormal regions being not easily detected by human eyes and providing the additional information for the diagnosis. The experiments using practical endoscopic images for performance evaluation showed that the proposed system is effective in the analysis of endoscopic image of the stomach.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.1
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• pp.47-54
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• 2008

In this paper, we propose an auto-detection algorithm of basal cell carcinoma(BCC) from the protophorphyrin IX(PpIX) fluorescence image induced by appling the methyl 5-aminolaevulinate(MAL) ointment-induced protophorphyrin IX(PpIX) to the skin tumour area and then shining the wood lamp on the area. The proposed algorithm first generates 3 mask areas-tumor area, suspected tumor area and tumor free area and then applies local watershed algorithm to the turner and the suspected tumor areas to make small watershed regions that include similar luminance value pixels. Next, small watershed regions are merged by hierarchical queue based fast region merging that uses the difference between the average luminance values of adjacent watershed regions as a region merging criterion and finally BCC regions are detected. 50 tissue samples are acquired from the tumour regions of 10 patients with BCC that are extracted by using the proposed algorithm and are performed pathological examination by expert dermatologist. Experiment result shows the rate of tumor detection from BCC lesion using presurgical in vivo of MAL-indeuced PpIX fluorescence has high sensitivity 94.1% and relatively high specificity 82.6%.

• Journal of the Korean Society of Radiology
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• v.10 no.5
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• pp.299-305
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• 2016

Despite of the development of medical equipments and technology. Pancreatic cancer has maked high false positive rate and low survival rate compared to other cancers. Therefore, early catch of pancreatic cancer is the only way to enhance the viability. It is important to find the exact location of the pancreas cancer in early stage. The method of optimum scan for early detection of pancreatic cancer on PET/CT exam is proposed. Examined the anatomical region that potentially can be missing from the supine position of ordinary pet/ct exam. The characteristics and usefulness of angle variation ($0^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $90^{\circ}$) of patients scan position is analyzed. The proposed scan method (named JJ-projection) is bringing advantage of anatomical discrimination by separating stomach, liver, gallbladder duodenum and pancreas. ROC curve analysis is shows to advantage of the JJ-Projection method. The sensitivity has increased 4.6% than the supine delay scan method, the results sensitivity has increased from 91% to 95.2%. The specificity has increased from 75.1% to 84%. Compared with the results observed in cancer by biological biopsy, The accuracy has increased from 86.8% to 94.1%.

• The Korean Journal of Nuclear Medicine
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• v.35 no.1
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• pp.52-60
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• 2001

Purpose: In young male patients who suffered several kinds of trauma with subsequent suspicious reflex sympathetic dystrophy syndrome, we performed three-phasic bone scan in order to investigate its usefulness. Materials and Methods: Patients with narrow range of age (21-25. mean $22.8{\pm}1.3$, all male) were included with suspicious reflex sympathetic dystrophy syndrome of 12 feet and 5 hands. Only one was bilateral feet case and 16 were ipsilateral (Rt:13, Lt:3). The etiologic traumas were 4 fractures, 4 sprains, 3 blunt trauma, 2 cellulitis, 1 tendon tear, 1 crush injury, 1 overexercise, and 1 unknown. Radiologically 3 showed osteoporotic changes. Three-phasic bone scans were performed $21.2{\pm}7.3wks$ after trauma. Results: According to symptom complex, confirmatory reflex sympathetic dystrophy syndrome 4 cases and suspicious 13 were analyzed. All confirmatory cases (100%) showed increased uptake at delay phase with periarticular accentuation. Of confirmatory 4 cases, 2 showed increased uptake in all three phases (perfusion: P, blood pool: B, and delay: D), and other 2 revealed decreased P but, both increased B and D. Of suspicious 13 cases, 9(69.2%) had increased D (4 periarticular and 5 focal), 2 decreased D, and 2 symmetric D. In 12 foot cases, so-called weight hearing patterns - increased contralateral sole at P and B - were revealed in 7(58.3%). Conclusion: Diffuse periarticular increased uptake at delay phase of three-phasic bone scan was a compatible finding to reflex sympathetic dystrophy syndrome in young male patients whose symptom complex strongly designated post traumatic reflex sympathetic dystrophy syndrome.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.3C
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• pp.374-386
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• 2004

The mammogram provides the way to observe detailed internal organization of breasts to radiologists for the early detection. This paper is mainly focused on efficiently detecting the Microcalcification's Region Of Interest(ROI)s. Breast cancers can be caused from either microcalcifications or masses. Microcalcifications are appeared in a digital mammogram as tiny dots that have a little higher gray levels than their surrounding pixels. We can roughly determine the area which possibly contain microcalifications. In general, it is very challenging to find all the microcalcifications in a digital mammogram, because they are similar to some tissue parts of a breast. To efficiently detect microcalcifications ROI, we used four sequential processes; preprocessing for breast area detection, modified multilevel thresholding, ROI selection using simple thresholding filters and final ROI selection with two stages of neural networks. The filtering process with boundary conditions removes easily-distinguishable tissues while keeping all microcalcifications so that it cleans the thresholded mammogram images and speeds up the later processing by the average of 86％. The first neural network shows the average of 96.66％ recognition rate. The second neural network performs better by showing the average recognition rate 98.26％. By removing all tissues while keeping microcalcifications as much as possible, the next parts of a CAD system for detecting breast cancers can become much simpler.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.3
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• pp.185-193
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• 2007

This review focuses on the use of $^{18}F-FDG$ PET/CT to evaluate second primary cancers. The emergence of a second primary cancer is an important prognostic factor in cancer patients. The early detection of a second primary cancer and the appropriate treatment are essential for reducing the morbidity and mortality associated with these tumors. Integrated $^{18}F-FDG$ PET/CT, which can provide both the metabolic and anatomic information of a cancer, has been shown to have a better accuracy in oncology than either CT or conventional PET. The whole body coverage and high sensitivity of $^{18}F-FDG$ PET/CT along with its ability to provide both metabolic and anatomic information of a cancer make it suitable for evaluating a second primary cancer in oncology. Whole body $^{18}F-FDG$ PET/CT is useful for screening second primary cancers with a high sensitivity and good positive predictive value. In order to rule out the presence of a second primary cancer or an unexpected metastasis, further diagnostic work-up is essential when abnormal findings indicative of a second primary cancer are found on the PET/CT images. PET/CT is better in detecting a second primary tumor than conventional PET.

• Journal of Oral Medicine and Pain
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• v.34 no.3
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• pp.295-301
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• 2009

Recently, bisphosphonate-associated osteonecrosis of the jaw(BONJ) is added to the list of diseases of the oromaxillofacial region. BONJ is defined as exposed bone in the jaw that does not heal within 8 weeks after identification, in a patient who has been received to bisphosphonates and has not taken radiation therapy to the craniofacial region. Bisphosphonates binded to bone mineral are concentrated in highly active remodeling site, reside in the skeleton for a long time, and do a role as powerful inhibitors of bone resorption. As the patients receiving bisphosphonates therapy grow in number, the patients of BONJ would go on increasing in Korea. We would like to present two patients who were suspected to BONJ, describe the outline of BONJ, and mention importance of our understanding about BONJ. BONJ is rare disease, but once it develops, its prognosis is very poor. Our adequate understanding of BONJ is necessary to prevent it and cope with it properly.

• Journal of the Korean Orthopaedic Association
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• v.54 no.6
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• pp.509-518
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• 2019

Purpose: Lymph node metastasis is a very important prognostic factor for all skin cancers and some sarcomas. A sentinel lymph node (SLN) biopsy is the most useful technique for identifying SLNs. Recently, a new generation of diagnostic tools, such as single photon emission computed tomography/computed tomography (SPECT/CT) and positron emission tomography/CT (PET/CT) enabled the detection of SLNs. This study compared the efficacy of PET/CT for detecting lymph node metastases with a SLN biopsy in a single medical center. Materials and Methods: From 2008 to 2018, 72 skin cancers of sarcoma patients diagnosed with some lymph node involvement in a whole body PET/CT reading were assessed. Patients suspected of lymph node metastasis were sent to biopsy and those suspected to be reactive lesions were observed. The analysis was performed retrospectively using the medical records, clinical information, PET/CT readings, and pathology results. Results: The age of patients ranged from 14 to 88 years and the mean follow-up period was 2.4 years. Twenty-two patients were suspected of a lymph node metastasis and confirmed. The sensitivity, specificity, positive predictive value and negative predictive value of PET/CT images in sarcoma and non-sarcoma tumors were increased significantly when the expert's findings were considered together. Conclusion: PET/CT is effective in detecting lymph node metastases.

• The Korean Journal of Nuclear Medicine
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• v.35 no.5
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• pp.301-312
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• 2001

Purpose: Stomach cancer is one of the most common malignancies in Korea, but there is no report on FDG PET in patients with stomach cancer. We observed findings of FDG PET in patients with stomach cancer. Materials and Methods: In 13 patients with pre-operative stomach cancer, PET and CT were performed. Primary lesion and regional lymph nodes detection were aualyzed. Correlation between FDG uptake ratio and each prognostic factor of primary lesion was analyzed. In 19 patients diagnosed as recurrence or displaying suspicious symptoms, conventional work up including tumor marker and PET were performed. Recurrence detection of anastomotic site, distant metastasis, and tumor marker elevation were analyzed. Results: Sensitivity for primary lesion detection was 83.3% (CT 71.4%) and two submucosal lesions were undetected. FDG uptake ratio was variable and had no correlation with invasion-depth, size, Borrmann type, staging and differentiation. Sensitivity for regional lymph node detection was 58.3% (CT 58.3%) and the lesions less than 1cm were undetected. Sensitivity for recurrence detection was 100% but there were three false positives. Sensitivity for distant metastasis detection was 64.3% and significantly higher than that of conventional work-up (21.4%). Average of tumor marker level in patients who were confirmed as recurrence was higher than false positive. Conclusion: PET is more useful than conventional work up in distant metastasis detection when recurrence is suspected. In pre-operative stomach cancer, PET is comparable to CT for detection of primary lesion and regional lymph node metastasis and detection of distant metastasis requires further study.