• Archives of Plastic Surgery
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• v.41 no.2
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• pp.171-173
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• 2014

Preoperative perforator marking for deep inferior epigastric artery perforator flaps is vital to the success of the procedure in breast reconstruction. Advances in imaging have facilitated accurate identification and preselection of potentially useful perforators. However, the reported imaging accuracy may be lost when preoperatively marking the patient, due to 'mapping errors', as this relies on the use of 2 reported vectors from a landmark such as the umbilicus. Observation errors have been encountered where inaccurate perforator vector measurements have been reported in relation to the umbilicus. Transcription errors have been noted where confusing and wordy reports have been typed or where incorrect units have been given (millimetres vs. centimetres). Interpretation errors have also occurred when using the report for preoperative marking. Furthermore, the marking process may be unnecessarily time-consuming. We describe a bespoke template, created using an individual computed tomography angiography image, that increases the efficiency and accuracy of preoperative marking. The template is created to scale, is individually tailored to the patient, and is particularly useful in cases where multiple potential suitable perforators exist.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.859-861
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• 2005

X-ray를 이용한 CT(Computed Tomography : 이하 CT)영상은 사물에 대해 회전하면서 X-ray가 투과하여 감약 정도에 따라서 영상을 획득하지만 검사 목적과는 관계없이 발생되는 통계적인 오차로 인해 정확한 CT영상의 구성을 교란하거나 방해하여 영상의 질을 저하시키고 미세 부분의 관찰 능력을 감소시키는 장해 음영인 아티팩트(artifact)라는 노이즈가 발생한다. 이러한 노이즈를 제거하는 필터를 설계 할 때는 두 가지 고려해야 할 사항이 있는데 첫째는 영상내의 노이즈을 정확히 판단하여 효과적으로 제거해야 하며, 둘째로는 원래의 영상에 가깝도록 경계와 같은 세부 영역을 보존해야 한다는 점이다. 기존에는 mean 필터나 median 필터, 그리고 Gaussian 필터 등을 사용했지만 상세한 부분을 보존하기에는 실패하는 단점이 있다. 따라서 본문에서는 wavelet 변환을 하여 영상의 주파수 대역을 저주파 영역과 고주파 영역으로 분리하여 각각의 영역에서 노이즈를 제거할 수 있도록 적합한 필터를 설계하고 방법을 제안하여 그 필터를 CT 3차원 뇌혈관 영상에 적용하여 많은 노이즈를 제거하였고 낮은 Threshold값에서도 작은 혈관을 관찰 할 수 있었다.

• Childhood Kidney Diseases
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• v.26 no.2
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• pp.101-106
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• 2022

Nephrotic syndrome (NS) is a hypercoagulable state in which children are at risk of venous thromboembolism. A higher risk has been reported in children with steroid-resistant NS than in those with steroid-sensitive NS. The mortality rate of cerebral venous sinus thrombosis (CVST) is approximately 10% and generally results from cerebral herniation in the acute phase and an underlying disorder in the chronic phase. Our patient initially manifested as a child with massive proteinuria and generalized edema. He was treated with albumin replacement and diuretics, angiotensin-converting enzyme inhibitor, and deflazacort. Non-contrast computed tomography showed areas of hyperattenuation in the superior sagittal sinus when he complained of severe headache and vomiting. Subsequent magnetic resonance imaging revealed empty delta signs in the superior sagittal, lateral transverse, and sigmoid sinuses, suggesting acute CVST. Immediate anticoagulation therapy was started with unfractionated heparin, antithrombin III replacement, and continuous antiproteinuric treatment. The current report describes a life-threatening CVST in a child with steroid-dependent NS, initially diagnosed by contrast non-enhanced computed tomography and subsequently confirmed by contrast-enhanced magnetic resonance imaging, followed by magnetic resonance venography for recanalization, addressing successful treatment.

• Journal of Gastric Cancer
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• v.13 no.4
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• pp.266-272
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• 2013

We report our experience with two cases of situs inversus totalis, both involving patients diagnosed with gastric cancer. These were a 52-year-old male with a preoperative staging of cT1bN0M0 and a 68-year-old male with a staging of cT2N0M0, both of whom underwent surgery. The former was found to have vascular anomalies in the preoperative computed tomography, so we performed a computed tomography angiography with three-dimensional reconstruction. Laparoscopy-assisted distal gastrectomy with Billroth I anastomosis was performed with D1+ lymph node dissection, and a small laparotomy was made for extracorporeal anastomosis. In contrast, the latter case showed no vascular anomalies in the preoperative computed tomography, and totally laparoscopic distal gastrectomy with delta anastomosis was performed with D1+ lymph node dissection. There were no intraoperative problems in either patient and they were discharged without postoperative complications. Histopathological examination revealed a poorly differentiated adenocarcinoma (pT2N0M0) and a well-differentiated adenocarcinoma (pT1aN0M0), respectively.

• Archives of Plastic Surgery
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• v.36 no.2
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• pp.140-146
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• 2009

Purpose: Autologous breast reconstruction with abdominal tissue is one of the best options after mastectomy. In a free transverse rectus abdominis myocutaneous(TRAM) or deep inferior epigastric artery perforator(DIEP) flap, a preoperative evaluation of the precise location of perforating vessels and vascular run - off systems is required. The objective of this report is to demonstrate the usefulness of multidetector computed tomography(MDCT) in the preoperative planning of patients undergoing breast reconstruction with abdominal flap. Methods: From June 2006 to January 2008, 28 patients underwent MDCT evaluation before breast reconstruction. All subjects were females with an age range of 30 to 55 years. The CT scan was performed using a 64 - slice MDCT scanner(Brilliance 64; Philips Medical Systems, Best, Netherlands). Results: One perforator or two major perforators were marked on image in good relation with a hand - held Doppler examination and intraoperative findings. All vascular run - off systems were cleared before operation. Conclusion: Preoperative evaluation of perforator arteries with MDCT angiography is beneficial in patients undergoing breast reconstruction. This technique provides a noninvasive approach of the vascular anatomy of the entire anterior abdominal wall.

• Journal of Chest Surgery
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• v.37 no.7
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• pp.570-577
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• 2004

CT angiography is now available to evaluate the early graft patency after coronary bypass surgery. We investigated whether patency or occlusion of the bypass grafts can be visualized by CT angiography and what factors effect the visuality. Material and Method: Fifty patients underwent scanning with a 4-slice computed tomographic scanner (Somatom Volume ZoomTM; Siemens, Germany) before being discharged after coronary artery bypass grafting. To evaluate graft patency and relationship between the quality of graft image and the characteristics of the diseased coronary vessels, 50 internal thoracic artery grafts, 18 radial artery grafts, and 56 vein grafts were included in this study. Result: All vein grafts (24 grafts; 32 anastomoses) to left coronary artery system were well visualized, but 3 grafts (4.7%) of 30 vein grafts (35 anastomoses) to right coronary artery system were not visualized. The latter was also occluded in invasive coronary angiographic study. Thirty-nine (78%) internal thoracic artery grafts were well visualized, 8 (16%) faintly visualized, and 3 (6%) not visualized, but all the internal artery grafts were well patent in invasive coronary angiographic study. Conclusion: Unvisualized vein grafts in CT angiography means occlusion of the grafts, but unvisualized arterial grafts in CT angiography may not mean occlusion of the graft but result from competitive flow between the graft and coronary artery. To confirm patency of the unvisualized arterial grafts, invasive coronary angiography is needed.

• Proceedings of the KOSOMBE Conference
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• v.1994 no.12
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• pp.26-27
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• 1994

The first step implementation of a hospital-wide Picture Archiving Communications System (PACS) at a newly built hospital Samsung Medical Center (SMC), is described. Current clinical operation encompasses the fiber optics delivery of direct-interfaced magnetic resonance imager (LRI), X-ray computed tomography (CT). digital subtraction angiography (DSA) and computed radiography (CR) digital images via high performance file server to the departments of radiology, neurosurgery, orthopedics surgery, neurology, emergency room and the surgical intensive care unit.

• Korean Journal of Radiology
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• v.21 no.12
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• pp.1285-1293
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• 2020

Objective: To evaluate the effects of vasodilators on contrast enhancement and transluminal attenuation gradient (TAG) of coronary arteries at coronary computed tomography angiography (CCTA). Materials and Methods: We retrospectively reviewed CCTA scans of patients who underwent double-acquisition CCTA; CCTA without a vasodilator, and CCTA during a intravenous (IV) infusion of nitrate. Among them, we enrolled 19 patients who had no significant atherosclerotic lesions or coronary spasms. In the control group, 28 patients were enrolled who showed normal coronary arteries on CCTA, which was acquired by a conventional method (sublingual vasodilator). We measured the TAG and Hounsfield units for each of the three major epicardial coronary arteries (reported as 'ProxHU') and then compared the results between the nitrate administration methods (CT without vasodilator [CT_pre], CT with IV vasodilator [CT_iv], and CT with sublingual vasodilator [CT_sub]). Results: The mean TAG showed a significant difference between the coronary arteries (right coronary artery [RCA] > left anterior descending artery [LAD] > left circumflex artery [LCX], p < 0.05), while there was no difference in ProxHU of each coronary artery in all three types of nitrate administration methods (p > 0.05). The TAG of CT_pre group showed steeper slope than those of vasodilator groups (CT_iv and CT_sub) on LAD and LCX ([LAD: CT_pre = -22.1 ± 6.66, CT_iv = -16.76 ± 5.78, and CT_sub = -16.47 ± 5.78, p = 0.005], [LCX: CT_pre = -31.26 ± 17.43, CT_iv = -23.74 ± 14.06, and CT_sub = -20.94 ± 12.15, p = 0.051]), while that of RCA showed no significant differences (p = 0.600). When comparing proxHU, CT_iv showed higher proxHU than that of CT_pre or CT_sub, especially on LCX (CT_pre = 426.7 ± 68.3, CT_iv = 467.9 ± 84.9, and CT_sub = 404.9 ± 63.3, p = 0.013). ProxHU showed a negative correlation with TAG on all three of methods (r = -0.280, p < 0.001). Conclusion: TAG in CCTA was significantly affected by vasodilator administration. Both TAG and ProxHU of coronary arteries tend to increase with vasodilator administration on CCTA.

• Korean Journal of Radiology
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• v.24 no.11
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• pp.1081-1092
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• 2023

Objective: To investigate the incidence of microvascular myocardial ischemia in diabetic patients without obstructive coronary artery disease (CAD) and its relationship with angina. Materials and Methods: Diabetic patients and an intermediate-to-high pretest probability of CAD were prospectively enrolled. Non-diabetic patients but with an intermediate-to-high pretest probability of CAD were retrospectively included as controls. The patients underwent dynamic computed tomography-myocardial perfusion imaging (CT-MPI) and coronary computed tomography angiography (CCTA) to quantify coronary stenosis, myocardial blood flow (MBF), and extracellular volume (ECV). The proportion of patients with microvascular myocardial ischemia, defined as any myocardial segment with a mean MBF ≤ of 100 mL/min/100 mL, in patients without obstructive CAD (Coronary Artery Disease-Reporting and Data System [CAD-RADS] grade 0-2 on CCTA) was determined. Various quantitative parameters of the patients with and without diabetes without obstructive CAD were compared. Multivariable analysis was used to determine the association between microvascular myocardial ischemia and angina symptoms in diabetic patients without obstructive CAD. Results: One hundred and fifty-two diabetic patients (mean age: 59.7 ± 10.7; 77 males) and 266 non-diabetic patients (62.0 ± 12.3; 167 males) were enrolled; CCTA revealed 113 and 155 patients without obstructive CAD, respectively. For patients without obstructive CAD, the mean global MBF was significantly lower for those with diabetes than for those without (152.8 mL/min/100 mL vs. 170.4 mL/min/100 mL, P < 0.001). The mean ECV was significantly higher for diabetic patients (27.2% vs. 25.8%, P = 0.009). Among the patients without obstructive CAD, the incidence of microvascular myocardial ischemia (36.3% [41/113] vs. 10.3% [16/155], P < 0.001) and interstitial fibrosis (69.9% [79/113] vs. 33.3% [8/24], P = 0.001) were significantly higher in diabetic patients than in the controls. The presence of microvascular myocardial ischemia was independently associated with angina symptoms (adjusted odds ratio = 3.439, P = 0.037) in diabetic patients but without obstructive CAD. Conclusion: Dynamic CT-MPI + CCTA revealed a high incidence of microvascular myocardial ischemia in diabetic patients without obstructive CAD. Microvascular myocardial ischemia is strongly associated with angina.

• Journal of radiological science and technology
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• v.41 no.2
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• pp.123-128
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• 2018

Recently, the use of contrast agents has been increasing as a broader range of tests and dynamic tests have become common due to the development of equipment and imaging techniques such as Multi-Detector CT. However, the side effects of using contrast agents have been reduced by the development of non-ionic contrast agents, but they are still occurring often. The purpose of this study was to propose a method to minimize the side effect of contrast agent by using the amount of contrast agent injected to the brain angiography test to suppress excessive use of contrast agent and analyze the amount of contrast agent. Patients who were prescribed Brain Angiography due to cerebrovascular disease, According to the results of the comparison of the results obtained by dividing into 4 groups of 10ml each according to the amount of contrast medium injected with contrast agent according to the BMI of the patient, BA and SNR were not different between groups, and even if the amount of contrast injection was reduced, there was no problem in the evaluation of CT angiography through 3D reconstruction. This result shows that even if the contrast medium is injected into the blood vessels of the patient first and then the contrast medium is used as the physiological saline solution, the contrast medium is reduced by 40% it can be expected to minimize.