• The Science & Technology
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• v.17 no.5 s.180
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• pp.42-44
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• 1984

• Imaging Science in Dentistry
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• v.30 no.2
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• pp.127-131
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• 2000

A 19-year-old man was referred to Seoul National University Dental Hospital for evaluation of a large painless swelling of the left mandibular angle area in August, 1999. The growth had been first noted 6 years ago. He had visited other hospital in 1997. In spite of the treatment given at the hospital, the mass continued to grow rapidly. Conventional radiographs in 1999 showed an expansile, lobulated, and destructive lesion of the left mandibular body. CT scan demonstrated an expansile mass with a corticated margin. Bony septa were seen within the lesion. Internal calcification noted on the bone-setting CT image, and corresponded to the hypointense area in T1-weighted MRI image. MRI clearly delineated the extent of the lesion which had heterogenous intermediate signal intensity in T1-weighted images and heterogenous hyperintense signal intensity in T2-weighted images. The lesion was well-enhanced. Histopathologically, the lesion was well demarcated. Multinucleated giant cells were presented in a fibrous background, demonstrating a storiform pattern. Areas of osteoid rimmed by a few osteoblasts were scattered throughout the lesion. Inflammatory cells, blood vessels, and hemosiderin deposition were also shown. CGCG may show lots of internal calcification foci on the CT, and varied signal intensity in MRI. More cases will be needed to understand the features of the CT & MR finding of CGCG.

• Journal of Yeungnam Medical Science
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• v.22 no.2
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• pp.191-198
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• 2005

Background: Computed tomography (CT) is commonly used to evaluate the degree of sinus involvement in cases of inverted papilloma (IP). However, CT cannot differentiate tumor from adjacent inflammatory mucosa or retained secretions. By contrast, magnetic resonance imaging (MRI) has been reported to be useful in distinguishing IP from paranasal sinusitis. This study investigated whether preoperative assessment with MRI and CT accurately predict the extent of IP.1) Materials and methods: CT and MRI were retrospectively reviewed in 9 cases of IP. Patients were categorized into stages based on CT and MRI findings, according to the staging system proposed by Krouse. The involvement of IP in each sinus was also assessed. Results: Differentiation of IP from inflammatory disease may be more successful in routine cases where the inflammatory mucosa has low signal intensity on T1-weighted images and very high signal intensity on T2-weighted images. CT imaging could not differentiate tumor from adjacent inflammatory mucosa or retained secretions. Conclusion: Preoperative MRI of IP can predict the location and extent of the tumor involvement in the paranasal sinuses and sometimes predicts malignant changes.

• Investigative Magnetic Resonance Imaging
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• v.25 no.2
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• pp.81-92
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• 2021

The role of neuroimaging in patients with acute ischemic stroke has been gradually increasing. The ultimate goal of stroke imaging is to make a streamlined imaging workflow for safe and efficient treatment based on optimized patient selection. In the era of multimodal comprehensive imaging in strokes, imaging based on computed tomography (CT) has been preferred for use in acute ischemic stroke, because, despite the unique strengths of magnetic resonance imaging (MRI), MRI has a longer scan duration than does CT-based imaging. However, recent improvements, such as multicoil technology and novel MRI acceleration techniques, including parallel imaging, simultaneous multi-section imaging, and compressed sensing, highlight the potential of comprehensive MR-based imaging for strokes. In this review, we discuss the role of stroke imaging in acute ischemic stroke management, as well as the strengths and limitations of MR-based imaging. Given these concepts, we review the current MR acceleration techniques that could be applied to stroke imaging and provide an overview of the previous research on each essential sequence: diffusion-weighted imaging, gradient-echo, fluid-attenuated inversion recovery, contrast-enhanced MR angiography, and MR perfusion imaging.

• Journal of the Korean Society of Radiology
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• v.81 no.5
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• pp.1234-1238
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• 2020

Calcium pyrophosphate dihydrate (CPPD) crystal deposition disease is characterized by chondrocalcinosis, which mainly affects the knees, wrists, pelvis, and rarely, the spine. According to previous reports, CPPD crystal deposits display heterogeneous enhancement on MRI. When combined with inflammation of the surrounding soft tissue, strong enhancement by CPPD crystal deposition may appear similar to imaging features of other conditions such as infectious spondylitis. In these conditions, CT plays an important role in differential diagnosis. Here, we present a case of CPPD crystal deposition disease in the ligamentum flavum of the cervical spine that showed intense enhancement on MRI.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.11
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• pp.2077-2082
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• 2008

Recent the advanced technologies in medical imaging such as magnetic resonance imaging (MRI) and computed tomography (CT) make doctors improve the diagnostic skill with detailed anatomical information. In general, it is necessary to get a number of MRI images in order to obtain more detail information. However, the performance of MRI machines of privately run hospitals is not good and thus we may obtain only a few of MRI images. If 3D surface reconstruction is accomplished with a few slices, then it generates 3D surface of poor qualify. This paper propose a way to Set a 3D surface of high quality from a few of number of slices. First of all, our algorithm detects the boundary of tissues which we want to reconstruct as a 3D object and find out the set of vortices on the boundary. And then we generate a 3D implicit surface to interpolate the boundary points by using radial basis function. Lastly, we render the 3D implicit surface by using Marching cube algorithms.

• Journal of Radiation Industry
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• v.17 no.4
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• pp.391-396
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• 2023

Currently, state-of-the-art devices such as SPECT, PET/CT, and PET/MRI are rapidly spreading nationwide, and the penetration rate of nuclear medical devices is also ranked fifth in the world. However, PET/MRI's system is slower and less common because it is more complex than PET/CT. The purpose of this study is to provide optimal information on PET/MRI according to the patient's disease. The subjects obtained information on head and neck cancer, pediatric patients, breast cancer patients, heart disease patients, lung cancer patients, and rectal cancer patients. We tried to accumulate protocols by obtaining a lot of information about each disease. In diagnosing head and neck cancer, it is believed that it is highly likely to be used in evaluating preoperative stage determination, recurrence and remote metastasis after treatment, and unclear primary cervical lymph node metastasis. Diagnosis and continuous follow-up of pediatric patients can increase patient benefits by minimizing radiation exposure. Breast cancer provides a comprehensive evaluation of the clinical need to determine the extent of disease in breast and local lymph nodes and the systematic stages of early diagnosis or recurrence. In diagnosing heart disease patients, MR-based PET motion correction helps to realize the full potential of PET images. For lung cancer patients, the clinical value and usefulness of the resolution and detection ability of integrated PET/MRI for soft tissues such as lung cancer will be sufficient. In diagnosing rectal cancer patients, the detection of missing residual diseases can change the clinical response evaluation for rectal cancer patients treated with TNT, and both the initial stage and treatment response evaluation are possible. Therefore, this literature study provided basic clinical data for PET/MRI tests.

• Journal of radiological science and technology
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• v.26 no.3
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• pp.25-31
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• 2003

This study was performed to evaluate the usefulness of Deconvolution perfusion CT in patients with acute cerebral infarction. Nine patients with acute cerebral infarction underwent conventional CT and cerebral perfusion CT within 23 hours of the onset of symptoms. The perfusion CT scan for each patient was obtained at the levels of basal ganglia and 1cm caudal to the basal ganglia. By special imaging software, perfusion images including cerebral blood volume(CBV), cerebral blood flow(CBF), and mean transit time(MTT) maps were created. The created lesions were evaluated on each perfusion maps by 3 radiolocical technician. MTT delay time was measured in the perfusion defect lesion and symmetric contralateral normal cerebral hemisphere. Lesion sire were measured on each perfusion map and compared with the value obtained by diffusion weighted MR imaging(DWMRI). All perfusion CT maps showed the perfusion defect lesion in all patients. There were remarkable CT delay in perfusion defect lesion. In comparison of lesion size between each perfusion map and DWMRI, the lesion on CBF map was the most closely correlated with the lesion on DWMRI(7/9). The size of perfusion defect lesion on MTT map was larger than that of lesion on DWMRI, suggesting that m map can evaluate the ischemic penumbra. Deconvolution Perfusion CT maps make it possible to evaluate not only ischemic core and ischemic penumbra but also hemodynamic status in perfusion defect area. These results demonstrate that perfusion CT can be useful to the diagnosis and treatment in the patients with acute cerebral ischemic infarction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5508-5512
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• 2015

Objective.: Sparganosis locations in humans are usually presented with a subcutaneous tissue of abdominal wall, chest, abdominal vicera and brain, but are rarely found in the breast. Methods. A case of sparganosis was confirmed by surgical excision of two parasites in a 76-year-old female patient present to a palpable mass in the right breast (presumed to have been sparganosis approximately 3 years ago). She had no history to direct ingestion of snakes or frogs, but had the history of drinking contaminated water. Mammography, ultrasonography, MRI, and FDG PET/CT imaging findings for patient were characteristic of sparganosis due to suspicion of breast cancer. Conclusions: The first route of infection in humans is drinking contaminated water. The second route is the ingestion of raw or partially cooked snakes or frogs. The third route is infected wound snake, frog muscle that attach to the case. However, only a few cases of drinking contaminated water have been reported in the country. Ultrasonography, MRI is known to be helpful for diagnosis of breast sparganosis. However, Mammography, ultrasonography, MRI, and FDG PET/CT for breast sparganosis is not reported present in the country. Reported the case and reviewed the related literature briefly.

• Journal of Korean Neurosurgical Society
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• v.46 no.4
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• pp.333-339
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• 2009

Objective : Few studies on the clinical spectrum of automated pressure-controlled discography (APCD)-defined positive discs have been reported to date. Thus, the present study was undertaken to analyze clinical parameters critical for diagnosis of discogenic pain and to correlate imaging findings with intradiscal pressures and pain responses in patients with APCD-positive discs. Methods : Twenty-three patients who showed APCD-positive discs were selected for analysis. CT discogram findings and the degrees of nuclear degeneration seen on MRI were analyzed in comparison to changes of intradiscal pressure that provoked pain responses; and clinical pain patterns and dynamic factors were evaluated in relation to pain provocation. Results : Low back pain (LBP), usually centralized, with diffuse leg pain was the most frequently reported pattern of pain in these patients. Overall, LBP was most commonly induced by sitting posture, however, standing was highly correlated with L5/S1 disc lesions (p<0.01). MRI abnormalities were statistically correlated with grading of CT discogram results (p<005); with most pain response observed in CT discogram Grades 3 and 4. Pain-provoking pressure was not statistically correlated with MRI grading. However, it was higher in Grade 3 than Grade 4. Conclusion : APCD-positive discs were demonstrated in patients reporting centralized low back pain with diffuse leg pain, aggravated by sitting and standing. MRI was helpful to assess the degree of nuclear degeneration, yet it could not guarantee exact localization of the painful discs. APCD was considered to be more useful than conventional discography for diagnosis of discogenic pain.