• Journal of Korean Neurosurgical Society
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• v.58 no.3
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• pp.184-191
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• 2015

Objective : Anterior communicating artery (AcomA) aneurysms represent the most common intracranial aneurysms and challenging to treat due to complex vascularity. The purpose of this study was to report our experience of endovascular treatment of AcomA aneurysms. Methods : Between January 2003 and December 2013, we retrospectively reviewed the medical records of 134 AcomA aneurysm patients available more than 6 months conventional angiographic and clinical follow-up results. We focused on aneurismal or AcomA vascular characters, angiographic and clinical follow-up results, and retreatment. Results : The rate of ruptured cases was 75.4%, and the small (<10 mm) aneurysms were 96.3%. Based on the subtypes defined by dominance of A1, 79 patients (59%) had contralateral A1 hypoplasia or agenesis. The immediate post-procedural angiography confirmed complete occlusion in 75.4%, partial occlusion in 24.6%. Procedure related complications were observed in 25 (18.6%) patients. Most of the adverse events were asymptomatic. Follow-up conventional angiography at ${\geq}6$ months was performed in all patients (mean 16.3 months) and major recanalization was noted in 6.7% and regrowth in one case. The aneurysm size (p=0.016), and initial treatment results (p=0.00) were statistically significant risk factors related to aneurysm recurrence. An overall improvement in mRS was observed during the clinical follow-up period and no rebleeding episode occurred. Conclusion : This study demonstrated that endovascular treatment is an effective treatment modality for AcomA aneurysms with low morbidity. Patients should take long term clinical and angiographic follow-up in order to assess the recurrence and warrant retreatment, especially ruptured, large, and initially incomplete occluded aneurysms.

• Journal of radiological science and technology
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• v.32 no.1
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• pp.61-67
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• 2009

Purpose : The purpose of this study was to investigate the applicability of poly-L-guluronic alginate (PGA) gel in vascular embolization with angiography simulation. Materials and Methods : To prepare a gel-forming PGA from no guluronate-rich Laminaria japonica, a new acid hydrolysis method was employed with a lower HCL concentration (0.03 M) and a shorter treatment time (5 min). The obtained PGAs were selected based on gel stability and viscosity. Glass aneurysm model was used to simulate gel embolization in vitro. Then, finally, the PGA was used to embolize the renal vascular system by using a rabbit model and angiography. Results : Glass aneurysm model was made to simulate gel embolization procedure. PGA solution was injected from pump through 2-way catheter. Subsequent injection of $CaCl_2$ successfully formed gels inside aneurysm model that conforming to its inner contour. In rabbit model, first, renal artery and aorta leading to the right kidney were ligated to block blood flow, then conventional contrast agent was injected through aorta to check the arterial patency to the left kidney. In sequential artery injection method, PGA and $CaCl_2$ were injected through renal artery sequentially via a single catheter. Re-injection of contrast agent after removing ligated aorta showed blood flow to the right kidney but no flow in the left kidney. This result demonstrated a complete blocking of blood flow due to gel formation in vascular bed of the left kidney. Conclusion : Instillation of calcium alginate into aneurysm model and arterial system in vivo produced an embolization that better fills and conforms to the contour of aneurysms or blocking vascular bed completely. Therefore, PGA was effective endovascular occlusion materials and provide an efficiency of vascular angiography.

• Journal of Trauma and Injury
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• v.22 no.2
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• pp.184-192
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• 2009

Purpose: This study was conducted to evaluate the effectiveness of the treatment strategy of transcatheter arterial embolization after pelvic CT angiography (CTA) in cases of traumatic pelvic hemorrhage. Methods: This is a retrospective analysis of pelvic hemorrhage patients who underwent transcatheter arterial embolization after pelvic CTA at our regional emergency center during a 31-month period. We reviewed the medical records and imagings of all these patients. Results: Transcatheter arterial embolization was performed in 17 patients (M:F=7:10, mean age=53.9) who underwent pelvic CTA for the evaluation of traumatic pelvic hemorrhage. Arterial bleeding was demonstrated on pelvic CTA in all patients, and the combined injury was also noted in 13 patients. The admission-to-CTA time was $84.53{\pm}66.92$ minutes, and the CTA-to-embolization time was $147.65{\pm}99.97$ minutes. Extravasation of contrast media or pseudoaneurysm was demonstrated on conventional angiography in all patients. Unilateral iliac artery embolization was performed in 8 patients, and bilateral iliac artery embolization was performed in 9 patients. Additional embolizations other than in the iliac arteries were performed in 7 patients. Initial hemostasis was achieved in 16 patients. One patient died of ongoing pelvic bleeding. Rebleeding occurred in only one patient and hemostasis was achieved with the second embolization. Another patient died of intracranial and facial bleeding in spite of pelvic hemostasis. The overall mortality was 11.8%, and there was no significant adverse effects in the other patients. Conclusion: Transcatheter arterial embolization after pelvic CTA is an effective treatment strategy in the management of traumatic pelvic hemorrhage patients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.393-400
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• 2020

Unlike conventional radiographic examinations, angiointerventional procedures have a high risk of radiation exposure to patients or operators due to prolonged radiation exposure time. This study was undertaken to examine effects of reducing the radiation risk by applying dose reduction fiber (DRF) shielding cloth during angiography. To investigate the properties of DRF shielding cloth, we measured the scattered radiation below and above a human phantom using a glass dosimeter, at site distances 10 cm away from the irradiated field. The results obtained reveal a 15 ~ 31% reduction of scattered radiation in the irradiation field, and 53 ~ 70% reduced radiation measured after phantom transmission. Taken together, our data indicate that application of DRF shielding cloth for radiation reduction at non-procedural sites during interventional procedure results in reduction of scattered doses to patients and operators, without affecting the medical examinations. We propose the use of DRF shielding during angiointerventional procedures, in order to reduce the risk of radiation exposure of patients and operators.

• Journal of the Korean Society of Radiology
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• v.82 no.6
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• pp.1619-1627
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• 2021

Central venous stenosis is a relatively common complication in hemodialysis patients; however, jugular venous reflux (JVR) and increased intracranial pressure are rare, and associated progressive visual disturbance was reported in only a few cases. Here, we report a case of JVR with visual disturbance and increased intracranial pressure. Notably, the MRI was accompanied by a dilatation of the superior ophthalmic vein, which was mistaken for a cavernous sinus dural arteriovenous fistula (CSdAVF). The patient had JVR on time-of-flight MR angiography (TOF-MRA) and severe stenosis of the left brachiocephalic vein on conventional angiography. After balloon angioplasty for central venous stenosis, he was discharged after improvement of his visual disturbance. Although JVR due to central venous stenosis and CSdAVF might show similar symptoms, treatment plans are different. Therefore, it is important to distinguish radiologically based on a thorough review of MRI and TOF-MRA and confirm the central venous stenosis on cerebral angiography for the accurate diagnosis.

• Investigative Magnetic Resonance Imaging
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• v.2 no.1
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• pp.96-103
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• 1998

Purpose : To assess the clinical utility of turbo contrast-enhanced magnetic resonance angiography(CE MRA) in the evaluation of the aortic arch and its major branches and to compare the image quality of CE MRA among different coils used. Materials and Methods : Turbo three-phase dynamic CE MRA encompassing aortic arch and its major branches was prospectively performed after manual bolus IV injection of contrast material in 29 patients with suspected cerebrovascular diseases at 1.0T MR unit. the raw data were obtained with 3-D FISH sequence (TR 5.4ms, TE 2.3ms, flip angle 30, slab thickness 80nm, effective slice thickness 4.0mm, matrix size $100{\times}256$, FOV 280mm). Total data acquisition time was 4. to 60 seconds. We subjectively evaluated the imge quality with three-rating scheme : "good" for unequivocal normal finding, "fair" for relatively satisfactory quality to diagnose 'normal' despite intravascular low signal, and "poor" for equivocal diagnosis or non-visualization of the origin or segment of the vessels due to low signal or artifacts which needs catheter angiography. At the level of the carotid bifurcation, it was compared with conventional 2D-TOF MRA image. Overall image quality was also compared visually and quantitatively by measuring signal-to-noise ratios (SNRs) of the ascending aorta, the innominate artery and both common carotid arteries among the three different coils used(CP body array(n=12), CP neck array(n=9), and head-and-neck(n=8). Results : Demonstration of the aortic arch and its major branches was rated as "good" in 55% (16/29) and "fair" in 34%(10/29). At the level of the carotid bifurcation, image quality of turbo CE MRA was same as or better than conventional 2D-TOF MRA in 65% (17/26). Overall image quality and SNR were significantlygreater with CP body array coil than with CP neck array or head-and-neck coil. Conclusions : Turbo CE MRA can be used as a screening exam in the evaluation of the major branches of the aortic arch from their origin to the skull base. Overall imagequality appears to be better with CP body array coil than with CP neck array coil or head-and-neck coil.

• The Korean Journal of Nuclear Medicine
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• v.38 no.3
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• pp.225-232
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• 2004

Purpose : Transient wall motion abnormality and contractile dysfunction of the left ventricle (LV) can be observed in patients with coronary artery disease due to post-stress myocardial stunning. To understand clinical characteristics of stress induced LV dysfunction, we have compared the findings of exercise stress test, myocardial perfusion SPECT and coronary angiography between subjects with and without post-stress LV dysfunction. Materials and Methods : Among subjects who underwent exercise stress test, myocardial perfusion SPECT and coronary angiography within a month of interval, we enrolled 36 patients with post-stress LV election fraction (LVEF) was $\geq5%$ lower than rest (stunning group) and 16 patients with difference of post-stress and rest LVEF was lesser than 1 %(non-stunning group) for this study. Treadmill exercise stress gated myocardial perfusion SPECT was performed with dual head SPECT camera using 740 MBq Tc-99m MIBI and coronary angiography was also performed by conventional Judkins method. Results : Stunning group had a significantly higher incidence of hypercholesterolemia than non-stunning group(45.5 vs. 7.1%, p=0.01). Stunning group also had higher incidence of diabetes mellitus and lower incidence of hypertension, but these were not statistically significant. Stunning group had larger and more severe perfusion defect in stress perfusion myocardial SPECT than non-stunning group(extent 18.2 vs. 9.2%, p=0.029; severity 13.5 vs. 6.9, p=0.040). Stunning group also had higher degree of reversibility of perfusion defect, higher incidence of positive exercise stress test and higher incidence of having severe stenosis ($80{\sim}99%$) in coronary angiography than non-stunning group, but these were not statistically significant. In stunning group, all of 4 patients without perfusion defect had significant coronary artery stenosis and had received revascularization treatment. Conclusion : Patients with post-stress LV dysfunction had larger and more severe perfusion defect and severe coronary artery stenosis than patients without post-stress LV dysfunction. All of the patients without perfusion defect in stunning group had significant coronary artery stenosis and needed revascularization. Therefore, we suggest that invasive diagnostic procedures and therapeutic interventions might be needed in patients with post-stress LV dysfunction.

• Journal of Cardiovascular Imaging
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• v.31 no.2
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• pp.108-115
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• 2023

BACKGROUND: Minimizing contrast dose and radiation exposure while maintaining image quality during computed tomography angiography (CTA) for transcatheter aortic valve replacement (TAVR) is desirable, but not well established. This systematic review compares image quality for low contrast and low kV CTA versus conventional CTA in patients with aortic stenosis undergoing TAVR planning. METHODS: We performed a systematic literature review to identify clinical studies comparing imaging strategies for patients with aortic stenosis undergoing TAVR planning. The primary outcomes of image quality as assessed by the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were reported as random effects mean difference with 95% confidence interval (CI). RESULTS: We included 6 studies reporting on 353 patients. There was no difference in cardiac SNR (mean difference, -1.42; 95% CI, -5.71 to 2.88; p = 0.52), cardiac CNR (mean difference, -3.83; 95% CI, -9.98 to 2.32; p = 0.22), aortic SNR (mean difference, -0.23; 95% CI, -7.83 to 7.37; p = 0.95), aortic CNR (mean difference, -3.95; 95% CI, -12.03 to 4.13; p = 0.34), and ileofemoral SNR (mean difference, -6.09; 95% CI, -13.80 to 1.62; p = 0.12) between the low dose and conventional protocols. There was a difference in ileofemoral CNR between the low dose and conventional protocols with a mean difference of -9.26 (95% CI, -15.06 to -3.46; p = 0.002). Overall, subjective image quality was similar between the 2 protocols. CONCLUSIONS: This systematic review suggests that low contrast and low kV CTA for TAVR planning provides similar image quality to conventional CTA.

• Journal of Veterinary Clinics
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• v.41 no.3
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• pp.157-164
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• 2024

The standard radiation protection method in the angiography suite involves the use of a thyroid shield, a lead apron, and lead glasses. However, exposure to substantial amounts of ionizing radiation can cause cataracts, tumors, and skin erythema. A newly developed curtain-type radiation protection device consists of a curtain drape composed of a five-layer bismuth and lead acrylic head-shielding plate, with both bearing an equivalent 0.25 mm lead thickness. In this study, a quality assurance phantom was used as the patient to create radiation scatter from the radiographic source, and an anthropomorphic mannequin phantom was used as the interventionalist to measure the radiation dose at seven different anatomical locations. Thermoluminescent dosimeters were used to measure the radiation dose. The experimental groups consisted of all-sided or one-sided curtain set-ups, the presence or absence of a conventional shielding system, and the orientation of beam irradiation. Consequently, the curtain-type radiation protection device exhibited better radiation protection range and capabilities than conventional radiation protection systems, especially in safeguarding the forehead, eyes, arms, and feet, with minimal radiation exposure. Moreover, the mean shielding ratios of the conventional shielding system and curtain-type radiation protection device were measured at 51.94% and 93.86%, respectively. Additionally, no significant decrease in the radiation protection range or capability was observed, even with changes in the beam orientation or one-sided protection. Compared with a conventional shielding system, the curtain-type radiation protection device decreased radiation exposure doses and improved comfort. Therefore, it is a potential new radiation protection device for veterinary interventional procedures.

• Journal of Korean Neurosurgical Society
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• v.43 no.6
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• pp.270-274
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• 2008

Objective : The purpose of this study was to report the morbidity, mortality, angiographic results, and merits of elective coiling of unruptured intracranial aneurysms. Methods : Ninety-six unruptured aneurysms in 92 patients were electively treated with detachable coils. Eighty-one of these aneurysms were located in the anterior circulation, and 15 were located in the posterior circulation. Thirty-six aneurysms were treated in the presence of previously ruptured aneurysms that had already undergone operation. Nine unruptured aneurysms presented with symptoms of mass effect. The remaining 51 aneurysms were incidentally discovered in patients with other cerebral diseases and in individuals undergoing routine health maintenance. Angiographic and clinical outcomes and procedure-related complications were analyzed. Results : Eight procedure-related untoward events (8.3%) occurred during surgery or within procedure-related hospitalization, including thromboembolism, sac perforation, and coil migration. Permanent procedural morbidity was 2.2%; there was no mortality. Complete occlusion was achieved in 73 (76%) aneurysms, neck remnant occlusion in 18 (18.7%) aneurysms, and incomplete occlusion in five (5.2%) aneurysms, Recanalization occurred in 8 (15.4%) of 52 coiled aneurysms that were available for follow-up conventional angiography or magnetic resonance angiography over a mean period of 13.3 months. No ruptures occurred during the follow-up period (12-79 months). Conclusion : Endovascular coil surgery for patients with unruptured intracranial aneurysms is characterized by low procedural mortality and morbidity and has advantages in patients with poor general health, cerebral infarction, posterior circulation aneurysms, aneurysms of the proximal internal cerebral artery, and unruptured aneurysms associated with ruptured aneurysm. For the management of unruptured aneurysms, endovascular coil surgery is considered an attractive alterative option.