• Journal of the Korean Society of Radiology
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• v.15 no.5
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• pp.621-628
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• 2021

Prior studies on frequency-related image quality analysis of intravascular ultrasound catheters are lacking both in Korea and abroad. Therefore, this study was conducted to prepare a standard for measuring the image quality using the program and to suggest a measuring method to researchers related to the quality analysis of intravascular ultrasound images. For the target, the vessel lumen size is 3.0 - 4.0 mm. Before using intravascular ultrasound, thoroughly clean the ultrasound catheter so that no air or foreign substances enter it. Normal vascular images and lesion vascular images of sufficiently dilated images were used. As a standard image acquisition method, the image of the end-systolic section, which has the best evaluation of vascular lesions when using intravascular ultrasound, was acquired retrospectively through the DCAS PACS program to set the standard. When setting the measurement method criteria, we proposed a standard setting method that corresponds to the concentric and eccentric circles of normal and lesion vessels. By applying this criterion, we proposed a method for measuring the lumen and lateral cavities of normal and lesion vessels of interest and background area. In conclusion, if the image quality of intravascular ultrasonography is measured through the method devised by these researchers, consistent quality measurement is possible regardless of the type of intravascular ultrasound catheter. Therefore, it is thought that it can be applied as a guideline for the actual image quality measurement method in the study related to intravascular ultrasound image quality.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.4
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• pp.352-356
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• 2009

Intravascular large B-cell lymphoma (IVLBCL) is a subtype of diffuse large cell lymphoma, characterized by proliferation of lymphoid cells in the intravascular space of various organs without causing a mass effect. Although $^{18}$F-FDG PET is a powerful imaging tool in lymphoma, the usefulness of $^{18}$F-FDG PET in the assessment of IVLBCL is still controversial. $^{99m}$Tc-MIBI, a tumor imaging radiopharmaceutical with a different mechanism from that of $^{18}$F-FDG, has been reported to be also effective in lymphoma. However, there is nearly no report on the efficacy of $^{99m}$Tc-MIBI in the assessment of IVLBCL. We present one case of IVLBCL that showed $^{99m}$Tc-MIBI accumulation in the involved bone marrow as an incidental finding, which was discrepant from that of $^{18}$F-FDG PET.

• Journal of Life Science
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• v.12 no.3
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• pp.306-316
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• 2002

The ultrastructural change of sciatic nerve and immunohistochemical changes of NGF, PCNA were studied at the transplanted segment of intravascular cultured neural stem cell in the rat sciatic nerve by 5 months after the sciatic nerve transection. The transplanted intravascular neural stem cells were differentiated into Schwann reals at the 20th day and these cells began to regenerate by the proliferation and hypertrophy. There were many remyelinating Schwann cells in the transplanted nerve in term of stimulation. According to NGF finding, we suggest preexisting Schwann cells may induce the differentiation of neural stem cells into regenerating Schwann cells. Electron microscopic changes were the remyelinating appearance, the increase of intraaxonal microtubules and enlarged mitochondria and contacting tell processes each other.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.4
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• pp.180-185
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• 2019

Masson's tumor or intravascular papillary endothelial hyperplasia is an inflammatory soft tissue lesion that rarely occurs in the maxillofacial region and skeletal system. Precise clinical and para-clinical investigation is necessary for the accurate diagnosis and correct treatment of this lesion. This paper presents a massive intravascular papillary endothelial hyperplasia lesion in the bony tissue of the mandible. Histopathology features, clinical appearance, and suitable management are discussed, with a complete review of the literature. The patient underwent composite resection of the lesion as well as reconstruction. No recurrence was observed during 6 years of follow-up. To the best of our knowledge, this is the fourth case of Masson's tumor in mandibular skeletal tissue, which has unique and distinctive features due to its size and location. A rare occurrence in skeletal tissue, complex clinical presentations, and complicated histopathologic findings present diagnostic challenges for treatment of this lesion.

• Tribology and Lubricants
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• v.15 no.3
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• pp.278-286
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• 1999

To predict the behavior of the intravascular micro active endoscope in the real human vascular system, a human mock circulation system was developed. The intravascular micro active endoscope which consists of micro active bending catheter and micro drug infusion catheter was driven in the velocity, Re number and temperature controlled flow. The three SMA (Shape Memory Alloy) zigzag type spring in the micro active bending catheter was heated by the electric current generated by PWM controller, and the shape memory effect made the actuator bend to any direction. The micro drug infusion catheter was driven through the inner hole of the micro active bending catheter. A mock circulation system is shaped from Ascending Arota to Femoral artery according to a human data (the data contains many vascular sizes and hydrographs of many control points). We developed a vascular model with glass and silicone tubes, and set the flow system with circulation parts, flow settling parts, and lots of valves. The heater and heat-controller was added to the How system to centre! the temperature of the How at 36.5$^{\circ}C$. The result showed that the developed intravascular micro active endoscope could be induced to any point in the vascular model.

• The Korean Journal of Pain
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• v.20 no.1
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• pp.26-30
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• 2007

Background: Epidural steroid injections (ESI) are a common treatment for spinal disorders. Previous research has shown that aspiration of the syringe is not a sensitive test for placement of an intravascular needle. Serious complications have been reported from injection of steroids and local anesthetics into the vascular space. In addition to safety concerns, the efficacy may decline with partial injection outside the desired epidural location. We hypothesized that incidence of vascular problems is increased in patients who undergo spine surgery compared with the patients who don't undergo spine surgery. We investigated the incidence of vascular problems during lumbosacral transforaminal ESI and we compared the difference of vascular problems between the patients who undergo spinal surgery and those patients who don't undergo spinal surgery. Methods: Two hundreds and three patients were consecutively recruited and they received 299 fluoroscopically guided lumbosacral transforaminal ESIs. Injection of contrast was performed under live dynamic fluoroscopy with using digital substraction analysis. The observed uptake pattern was classified into one of three categories: flashback, aspirated, and positive contrast with negative flashback and aspiration. Results: The vascular incidence rate was 20.4%. Transforaminal ESIs performed at S1 had avascular incidence rate of 27.8% compared with 17.7% for all the other lumbar injection sites. The sensitivity of spontaneous observation of blood in the needle hub or blood aspirate for predicting an intravascular injection in lumbar transforaminal ESIs was 70.4%. Conclusions: There is a high incidence of intravascular problems when performing transforaminal ESIs, and this is significantly increased in patients with previous spine surgery. Using a flash or blood aspiration to predict an intravascular injection is not sensitive therefore; a negative flash or aspiration is not reliable. Fluoroscopically guided procedures without contrast confirmation are prone to instill medications intravascularly. This finding confirms the need for not only fluoroscopic guidance, but also for contrast injection instillation when performing lumbosacral transforaminal ESIs, and especially for patients with previous spine surgery.

• Tribology and Lubricants
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• v.15 no.3
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• pp.272-277
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• 1999

The objective of this investigation is to examine the influence of the micro catheters, which mimic the intravascular micro active endoscopes, on local pressure changes and flow rate in an arterial branch model similar to the femoral artery of human. The effects of branch to main lumen flow rate ratios and the locations of a catheter tip were found to be significant on the local pressure changes. Relatively large pressure drops and an increase in shear stress due to the obstruction effects may induce an endothelial cell damage and a change in arterial wall permeability, which have been reported to be the primary cause of the initiation of the atherosclerosis and other major vascular diseases.

• The Journal of Korean Medicine
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• v.17 no.2 s.32
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• pp.237-244
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• 1996

The purpose of this study was to investigate the effect of ILIB(Intravascular Laser Irradiation of blood) on Hyperfibrinogenemia. 20 patients with fibrinogen level of over $400mg／d{\ell}$ were treated with IUB. After !0 times' treatment, changes of fibrinogen level and clinical symptom were observed. The results were as follows: 1. Fibrinogen level was decreased in all of cases. 2. Most cases were suffered from neural symptoms(headache, palpitation, etc), circulatory symptoms (dizziness, numbness, deficiency of sensation, etc), musculo-skeletal symptoms(L.B.P, neck stiffness, arthralgia, etc.), fatigue, pollakiuria, constipation. After treatment, neural and circulatory symptoms were improved considerably.

• Journal of Korean Neurosurgical Society
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• v.44 no.5
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• pp.341-344
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• 2008

The authors present a case of 68-year-old woman who underwent resection of a metastatic adenocarcinoma in the left parietooccipital area. The intraoperative course was uneventful; however, after closure of the scalp incision, increased bleeding from the suture line was noted. A computerized tomography scan that was performed immediately after operation revealed acute epidural hemorrhage with mass effect under the bone flap. The patient developed disseminated intravascular coagulation and immediate re-exploration was performed. This patient was successfully treated owing to early recognition of the condition and immediate treatment with transfusion. Neurosurgeons should be alert that hypercoagulabe state is common in cancer patients and consumptive coagulopathy can occur after resection of metastatic brain tumor.

• Journal of Korean Foot and Ankle Society
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• v.16 no.4
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• pp.276-279
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• 2012

Intravascular papillary endothelial hyperplasia (IPEH) known as Masson's hemangioma is a rare benign reactive vascular lesion caused by the abnormal proliferation of endothelial cells. The lesion occurs most commonly in the fingers, head and neck, but very rare in the foot. We report a case of IPEH in the foot treated with operative excision.