• Progress in Medical Physics
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• v.26 no.1
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• pp.52-58
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• 2015

The automated dental cavity detection program for a new concept intra-oral dental x-ray imaging device, an auxiliary diagnosis system, which is able to assist a dentist to identify dental caries in an early stage and to make an accurate diagnosis, was to be developed. The primary theory of the automatic dental cavity detection program is divided into two algorithms; one is an image segmentation skill to discriminate between a dental cavity and a normal tooth and the other is a computational method to analyze feature of an tooth image and take an advantage of it for detection of dental cavities. In the present study, it is, first, evaluated how accurately the DRLSE (Direct Regularized Level Set Evolution) method extracts demarcation surrounding the dental cavity. In order to evaluate the ability of the developed algorithm to automatically detect dental cavities, 7 tooth phantoms from incisor to molar were fabricated which contained a various form of cavities. Then, dental cavities in the tooth phantom images were analyzed with the developed algorithm. Except for two cavities whose contours were identified partially, the contours of 12 cavities were correctly discriminated by the automated dental caries detection program, which, consequently, proved the practical feasibility of the automatic dental lesion detection algorithm. However, an efficient and enhanced algorithm is required for its application to the actual dental diagnosis since shapes or conditions of the dental caries are different between individuals and complicated. In the future, the automatic dental cavity detection system will be improved adding pattern recognition or machine learning based algorithm which can deal with information of tooth status.

• Investigative Magnetic Resonance Imaging
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• v.7 no.2
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• pp.116-123
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• 2003

Purpose : The present study was undertaken to evaluate the usefulness of cerebral diffusion (DWI) and perfusion MR imaging (PWI) in rabbit models with hyperacute cerebral ischemic infarction. Materials and Methods : Experimental cerebral infarction were induced by direct injection of mixture of Histoacryl glue, lipiodol, and tungsten powder into the internal cerebral artery of 6 New-Zealand white rabbits, and they underwent conventional T1 and T2 weighted MR imaging, DWI, and PWI within 1 hour after the occlusion of internal cerebral artery. The PWI scan for each rabbit was obtained at the level of lateral ventricle and 1cm cranial to the basal ganglia. By postprocessing using special imaging software, perfusion images including cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) maps were obtained. The detection of infarcted lesion were evaluated on both perfusion maps and DWI. MTT difference time were measured in the perfusion defect lesion and symmetric contralateral normal cerebral hemisphere. Results : In all rabbits, there was no abnormal signal intensity on T2WI. But on DWI, abnormal high signal intensity, suggesting cerebral infarction, were detected in all rabbits. PWI (rCBV, CBF and MTT map) also showed perfusion defect in all rabbits. In four rabbits, the calculated square of perfusion defect in MTT map is larger than that of CBF map and in two rabbits, the calculated size of perfusion defect in MTT map and CBF map is same. Any rabbits do not show larger perfusion defect on CBF map than MTT map. In comparison between CBF map and DWI, 3 rabbits show larger square of lesion on CBF map than on DWI. The others shows same square of lesion on both technique. The size of lesion shown in 6 MTT map were larger than DWI. In three cases, the size of lesion shown in CBF map is equal to DWI. But these were smaller than MTT map. The calculated square of lesion in CBF map, equal to that of DWI and smaller than MTT map was three. And in one case, the calculated square of perfusion defect in MTT map was largest, and that of DWI was smallest. Conclusion : DWI and PWI may be useful in diagnosing hyperacute cerebral ischemic infarction and in e-valuating the cerebral hemodynamics in the rabbits.

• Parasites, Hosts and Diseases
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• v.51 no.4
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• pp.393-400
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• 2013

Ocular toxoplasmosis is a disease caused by the infection with Toxoplasma gondii through congenital or acquired routes. Once the parasite reaches the retina, it proliferates within host cells followed by rupture of the host cells and invasion into neighboring cells to make primary lesions. Sometimes the restricted parasite by the host immunity in the first scar is activated to infect another lesion nearby the scar. Blurred vision is the main complaint of ocular toxoplasmic patients and can be diagnosed by detection of antibodies or parasite DNA. Ocular toxoplasmosis needs therapy with several combinations of drugs to eliminate the parasite and accompanying inflammation; if not treated it sometimes leads to loss of vision. We describe here clinical features and currently available chemotherapy of ocular toxoplasmosis.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.116-120
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• 2008

Prostate cancer is the second leading cause of cancer death of men in western countries and the death related to this disease in Korea is also getting increased. Although anatomic imaging tools such as transrectal US or MRI have been playing a great role in detection of primary prostate lesion, the evaluation of regional lymph node or distant organ metastasis using these modalities is not successful. $^{18}F-FDG-PET$ scan is emerging diagnostic tool for various malignancies. Considering the usual characteristics of prostate cancer such as slow growing and osteoblastic metastasis, the application of FDG PET scan to this disease might be limited. However, in advanced prostate cancer refractory to chemotherapy, FDG PET scan show strong FDG uptake and SUV changes in serial PET scan can be a good indicator of treatment response. Although FDG PET can be useful only in limited cases of prostate cancer, its indication can be widened in future owing to rapid technical improvement and accumulated experiences in this field.

• Journal of Veterinary Clinics
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• v.18 no.4
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• pp.469-473
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• 2001

A 12-year-old bitch, Yorkshire terrier, was admitted to the Chungbuk National University animal hospital with draining from mammary masses in the left and right mammary glands. She was involved in the mammary masses, suffering bilateral inguinal hernia. Physical examination during the hospitalization demonstrated the masses in right (3 cm) and left (1.5 cm) mammary glands. Blood pool images didn\`t show the subtle increase in blood flow to the inguinal hernia, and the increase of radionuclide distribution to the mammary gland on the soft tissue phase. However, delayed bone images showed a very focal lesion in the right mammary gland. These findings were confirmed on a subsequent biopsy, which also revealed adenocarcinoma with areas of malignant new bone formation. We present a case of primary mammary adenocarcinoma with $^{99m}Tc-MDP$ activity relative to normal bone. Tumor in the bitch demonstrates malignant new bone formation as the likely mechanism for the marked radiotracer avidity.

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2000.09a
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• pp.25-25
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• 2000

N. caninum infections have been associated with neonatal paresis as well as abortion around the world. Bovine abortion induced by N. caninum was first reported in 1997 in Korea. Diagnosis of N. caninum infection is usually based on histopathology and immunohistochemical detection of organism. However, often the tissues having lesion suggestive of N. caninum infection were negative on immunohistochemistry. (omitted)

• Korean Journal of Head & Neck Oncology
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• v.3 no.1
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• pp.5-13
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• 1987

Cancer of the head and neck is an uncommon disease accounting for 5 % of all cancers. In an anatomic area so readily visible and palpable for examination without special and expensive diagnositic tools, it is unfortunate that many patients still present with advanced diseases. Since the prognosis is so intimately related to stage of disease, it is very important to detect the earliest stage of cancer with a complete head and neck examination. In the evaluation of cancer at any anatomic site, the description of the extent of the lesion is important. Not only does proper staging of the tumor lead to make decision of the most appropriate treatment, it also serves as a guide for the results of treatment. Proper staging demands a careful clinical assesment of the extent of the cancer. The current staging system for head and neck cancer uses the TNM system devised by American Joint Committee for Cancer Staging and End Result Reporting. T represent the primary tumor, N, regional nodal metastases, and M, distant metastases. The detection, diagnosis, and appropriate treatment of eary cancer will result in improved survival.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.877-878
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• 2006

In this paper, we propose a skin lesion detection to develop the system of fluorescence image analysis to identify the fluorescence of topical methyl aminolevulinate(MAL) idduced PpIX in patients with BCC accurately. By fluorescence image analysis we define the border between tumo and tumor-free areas on fluorescence image after topical application of MAL ointment. We excised both the tumor and peri-tumoral areas widely from the 10 patients with BCC, and divided tissue samples into 3 area, such as tumor area, suspected tumor area, tumor-free area, respectively. Our proposed method migt play a role as an adjunctive tool to define the border between tumor and tumor-free areas for Mohs' micrographic surgery.

• The Korean Journal of Cytopathology
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• v.18 no.2
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• pp.112-118
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• 2007

Fine needle aspiration cytology (FNAC) has become a highly preferred, minimally invasive diagnostic tool of choice in the diagnosis of a palpable breast mass owing to its sensitivity, specificity, cost-effectiveness, and expediency. Although breast needle biopsies have been widely employed recently due to the increased detection rate of non-palpable early lesions, the importance of the use of FNAC cannot be underestimated. It comprises part of the diagnostic triad for the breast along with a physical examination and mammography, which together contribute to an increasing diagnostic accuracy. The differential diagnosis of a benign and malignant lesion is of the utmost importance in the diagnosis of breast lesions, and therefore the understanding of the possible diagnostic pitfalls is of great importance.

• Journal of Chest Surgery
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• v.23 no.3
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• pp.537-541
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• 1990

Early esophageal carcinoma is defined as a lesion wherein invasion is confined to the mucosa and submucosa without metastasis to lymph node or other organs. Postoperative 5-year survival rate for early esophageal carcinoma is much superior than advanced carcinoma. Unfortunately, because of the anatomic characteristic of esophagus and absence of specific early symptoms, detection is frequently belated, and advanced disease is present at the time of the initial diagnosis. We experienced 2 cases of early esophageal carcinoma. They complained no specific symptoms. The diagnosis was made by barium esophagogram, esophagofiberscopy with dye staining and endoscopic biopsy. We performed esophagectomy with esophagogastrostomy. All had good postoperative course without any complication. We concluded that the combined use of double contrast radiography, esopagofiberscopy aided by intraluminal staining with Toluidine blue or Lugol`s solution, and endoscopic biopsy is very important in the diagnosis of early esophageal carcinoma in high risk patient group.