• Journal of Korean Neurosurgical Society
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• v.39 no.2
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• pp.87-91
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• 2006

Objective : Management of recurrent vestibular schwannomas[VS] after microsurgery or radiosurgery is a complicated subject. However, few studies have documented the outcome of recurrent VS. The authorsreviewclinicalexperience of recurrent VS management and analyzed the efficacy of treatment modalities. Methods : Between 1990 and 2002, 293 patients harboring unilateral VS underwent, microsurgery, radiosurgery, microsurgery followed by radiosurgery. Of these, 26 procedures [in 20 patients] were performed to assessed from an increased tumor size by magnetic resonance imaging[MRI]. The mean age of patients with recurred VS was 46.9 years and the mean follow-up period was 68 months. Radiological characteristics were investigated and growth rates of recurred tumors were calculated by measuring changes in tumor diameter on MRI after treatment. Results : MRI characteristics revealed a lobulated contour in 75% and a cyst in 60% of the patients. Only 1 patient showed neither lobulation nor a cyst. The average diameter of the recurrent tumors were 36.9mm. The overall tumor control rate for initial management was 87.4%, 94.7%, and 98.5% for microsurgery, radiosurgery, and microsurgery plus radiosurgery, respectively. However, control rates for recurrent tumors were lower at 85%, 63%, and 80%, respectively. Conclusion : A cystic nature and a lobulated tumor contour are frequent clinical characteristics of recurrent VS. Microsurgery or microsurgery followed by radiosurgery shows little difference in tumor control rate for primary and recurrent VS. However, radiosurgery alone appears to be less beneficial for recurrent VS.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.10
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• pp.5179-5196
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• 2019

To explore an effective non-invasion medical imaging diagnostics approach for hepatocellular carcinoma (HCC), we propose a method based on adopting the multiple technologies with the multi-parametric data fusion, transfer learning, and multi-scale deep feature extraction. Firstly, to make full use of complementary and enhancing the contribution of different modalities viz. multi-parametric MRI images in the lesion diagnosis, we propose a data-level fusion strategy. Secondly, based on the fusion data as the input, the multi-scale residual neural network with SPP (Spatial Pyramid Pooling) is utilized for the discriminative feature representation learning. Thirdly, to mitigate the impact of the lack of training samples, we do the pre-training of the proposed multi-scale residual neural network model on the natural image dataset and the fine-tuning with the chosen multi-parametric MRI images as complementary data. The comparative experiment results on the dataset from the clinical cases show that our proposed approach by employing the multiple strategies achieves the highest accuracy of 0.847±0.023 in the classification problem on the HCC differentiation. In the problem of discriminating the HCC lesion from the non-tumor area, we achieve a good performance with accuracy, sensitivity, specificity and AUC (area under the ROC curve) being 0.981±0.002, 0.981±0.002, 0.991±0.007 and 0.999±0.0008, respectively.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.4
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• pp.151-163
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• 2009

Objectives : In the assessment of the lumbar spine by magnetic resonance imaging (hereinafter, "MRI"), changes in the paraspinal muscles are overlooked. The purpose of our study is to examine the correlation between the multifidus muscle atrophy on MRI findings and the clinical findings in low back pain (hereinafter, "LBP") patients. Methods : The retrospective study on 38 LBP patients, presenting either with or without associated leg pains, was undertaken. The MRI findings on the patients were visually analysed to find out a lumbar multifidus muscle atrophy, disc herniation, disc degeneration, spinal stenosis and nerve root compressions. The clinical history in each case was obtained from their case notes and pain drawing charts. Results : The lumbar multifidus muscle atrophy has occurred from more than 80% of the patients with LBP. Most of lumbar multifidus muscle atrophies have increased from lower level of lumbar spine. It was bilateral in the majority of the cases. In addition, multifidus muscle atrophy was correlated to the patient's age, disc degenerations and spinal stenosis. On the contrary, gender, the duration of LBP, referred leg pain, disc herniation and nerve root compressions had no relevance to multifidus muscle atrophies. Therefore, when assessing the MRIs of the lumbar spine, we should have more attetion on multifidus muscle, because it has lot's of information about spinal neuropathy problems. Conclusions : Therefore, the examination of multifidus muscle atrophies should be considered when assessing the MRIs of the lumbar spine. In addition, it helps to evaluate and plan the treatment modalities of LBP. Moreover, it prevents from LBP by discovering the importance between the multifidus muscle and the spine stabilization exercise.

• BMB Reports
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• v.55 no.6
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• pp.267-274
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• 2022

Molecular imaging is used to improve the disease diagnosis, prognosis, monitoring of treatment in living subjects. Numerous molecular targets have been developed for various cellular and molecular processes in genetic, metabolic, proteomic, and cellular biologic level. Molecular imaging modalities such as Optical Imaging, Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT), and Computed Tomography (CT) can be used to visualize anatomic, genetic, biochemical, and physiologic changes in vivo. For in vivo cell imaging, certain cells such as cancer cells, immune cells, stem cells could be labeled by direct and indirect labeling methods to monitor cell migration, cell activity, and cell effects in cell-based therapy. In case of cancer, it could be used to investigate biological processes such as cancer metastasis and to analyze the drug treatment process. In addition, transplanted stem cells and immune cells in cell-based therapy could be visualized and tracked to confirm the fate, activity, and function of cells. In conventional molecular imaging, cells can be monitored in vivo in bulk non-invasively with optical imaging, MRI, PET, and SPECT imaging. However, single cell imaging in vivo has been a great challenge due to an extremely high sensitive detection of single cell. Recently, there has been great attention for in vivo single cell imaging due to the development of single cell study. In vivo single imaging could analyze the survival or death, movement direction, and characteristics of a single cell in live subjects. In this article, we reviewed basic principle of in vivo molecular imaging and introduced recent studies for in vivo single cell imaging based on the concept of in vivo molecular imaging.

• Journal of the Korean Society of Radiology
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• v.82 no.6
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• pp.1545-1555
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• 2021

Purpose The purpose of this study was to evaluate the rates of unacceptable diagnosis and clinically significant diagnostic discrepancy in radiology sections and imaging modalities through a peer review of teleradiology. Materials and Methods Teleradiology peer reviews in a Korean teleradiology clinic in 2018 and 2019 were included. The peer review scores were classified as acceptable and unacceptable diagnoses and clinically insignificant and significant diagnostic discrepancy. The diagnostic discrepancy rates and clinical significance were compared among radiology sections and imaging modalities using the chi-square test. Results Of 1312 peer reviews, 117 (8.9%) cases had unacceptable diagnoses. Of 462 diagnostic discrepancies, the clinically significant discrepancy was observed in 104 (21.6%) cases. In radiology sections, the unacceptable diagnosis was highest in the musculoskeletal section (21.4%) (p < 0.05), followed by the abdominal section (7.3%) and neuro section (1.3%) (p < 0.05). The proportion of significant discrepancy was higher in the chest section (32.7%) than in the musculoskeletal (19.5%) and abdominal sections (17.1%) (p < 0.05). Regarding modalities, the number of unacceptable diagnoses was higher with MRI (16.2%) than plain radiology (7.8%) (p < 0.05). There was no significant difference in significant discrepancy. Conclusion Peer review provides the rates of unacceptable diagnosis and clinically significant discrepancy in teleradiology. These rates also differ with subspecialty and modality.

• Journal of Biomedical Engineering Research
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• v.30 no.1
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• pp.1-9
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• 2009

Many types of small animal imaging modalities, like micro-CT, micro-PET, and micro-SPECT, have been recently developed worldwide. Small animal imaging systems are now recognized as indispensable tools to validate efficacy and safety of new drugs or new therapeutic methods using the animal disease models. With increasing demands for small animal imaging in biomedical research, multimodal small animal imaging systems, like micro-PET/CT or micro PET/MRI, are now also being developed. Small animal imaging with spatial resolution and sensitivity comparable to human imaging is quite challenging since laboratory small animals are much smaller than human beings. Research activities in Korea on small animal imaging systems are reviewed in this paper. In the field of micro-CT and micro-PET, many world-class technologies have been developed successfully in Korea. It is expected that the developed animal imaging system technologies can be used in the development of clinical imaging systems in Korea in the near future.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2008.03a
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• pp.5-5
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• 2008

Spinoglenoid cyst of the shoulder is a rare clinical entity and several treatment modalities have been reported. Recently, arthroscopy is effectively used via communication hole or posterior capsulotomy through the glenohumeral joint. With this method, the complete cystectomy is impossible if the cyst is a large size or extended anteriorly and there are few reports about such cases. We present extra-articular complete cystectomy through bursal space in 3 cases of huge and anteriorly extended spinoglenoid cysts. All patients were able to return to work with no restrictions and 2 patients who performed the follow up MRI demonstrated complete resolution of the cyst and some recovery of the mass of infraspinatus muscle.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.2 no.2
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• pp.63-68
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• 2016

Peptides have been developed for in vivo imaging probes against to the specific biomarker in the biological process of living systems. Peptide based imaging probes have been applied to identify and detect their active sites using imaging modalities, such as PET, SPECT and MRI. Especially, tumor receptor imaging with the peptides has been widely used to specific tumor detection. This review discusses the targeting peptides that have been successfully characterized for tumor diagnosis by receptor imaging.

• 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.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.126-129
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• 2008

Renal cell carcinoma is the most common histological type of renal malignancy, predominant in men and the primary treatment modality of this tumor is surgery. The role of diagnostic imaging in the management of this tumor is the evaluation of extent of disease as well as the detection and characterization of renal mass. US has long been a routine screening tool for kidney but tomographic imaging modalities such as CT and MRI begin to be also commonly used these days. On the other hand, the sensitivity of $^{18}F-FDG-PET$ in detection of renal mass is relatively low because of inherent limitation caused by FDG excretion pathway despite avid uptake of FDG to tumor cell per se. Many studies revealed FDG PET scan could play an important role in detection of metastatic lesions although the sensitivity for the detection of primary lesion is not so high. Furthermore, development of PET/CT scanner will make it possible to expand the indication of FDG PET scan in this malignancy.