• 대한방사선기술학회지:방사선기술과학
• /
• 제41권2호
• /
• pp.109-113
• /
• 2018

Despite the continuous development of software, it is continuously pursued to enlarge the examination area of FOV in order to reduce the factors of inconsistency in images that appear in continuous examination during wide area examination using contrast agent such as whole body angiography. In this study, we investigated the optimal FOV by comparing the SNR values according to the changes of FOV. The change of the FOV was gradually changed to $270{\times}200$, $300{\times}223$, $330{\times}244$, $360{\times}266$ and $380{\times}281$. SE images at TR 450 msec and TE 10 msec, FSE images at TR 2,000 msec, TE 80 msec, and GE images were scanned at TR 117 msec, and TE 16 msec. SNR values were calculated from the mean values of signal intensities of five phantom images and the signal intensity values of four background standard deviations. As a result of the study, the signal intensity and the SNR value according to the change of the FOV value gradually increased as the FOV was increased, but it was found that the SNR value decreased at a constant size. In conclusion, the results are different from previous studies that the SNR increases as the FOV increases. The cause of these results could not be confirmed. However methods that can be imaged and included within the effective FOV should be considered.

• Annals of Clinical Neurophysiology
• /
• 제20권2호
• /
• pp.79-84
• /
• 2018

Background: Pulsatility of cerebral arteries and aortic stiffness have been associated with white matter hyperintensities (WMH). We explored which is better correlated with the severity of WMH in a population with acute lacunar infarct. Methods: We included patients with acute small subcortical infarcts who underwent transcranial Doppler (TCD) and brachial ankle pulse wave velocity (baPWV). Exclusion criteria were any stenosis or occlusion on major cerebral arteries on magnetic resonance angiography; poor temporal insonation windows; ankle brachial index < 0.9; and atrial fibrillation. We assessed the performance of the pulsatility index of bilateral middle cerebral arteries (PI-MCA) and baPWV for predicting moderate-to-severe WMH, defined as an Age Related White Matter Changes score > 5, and then sought to find independent predictors using binary logistic regression analysis. Results: Eighty-three patients (56 males, mean age $61.5{\pm}11.4$) participated in the study. Uni-variate analysis showed old age and high PI-MCA were significantly correlated with moderate-to-severe WMH. However, baPWV was not associated with the severity of WMH. Multivariate analysis revealed old age (odds ratio per 1-year increase, 1.068; p = 0.044) and upper tertile of PI-MCA (odds ratio, 5.138; p = 0.049) were independently associated with moderate-to-severe WMH. Receiver-operating characteristics showed PI-MCA differentiated those with and without moderate-to-severe WMH with an area under the curve of 0.719. Conclusions: PI-MCA derived from TCD was better correlated with the severity of WMH than baPWV in a population with lacunar infarction. Pulsatility of cerebral arteries may better predict cerebral small vessel disease than the aortic stiffness index.

• Clinical and Experimental Pediatrics
• /
• 제52권9호
• /
• pp.1044-1047
• /
• 2009

내경 동맥 박리는 드물기는 하나 소아 허혈성 뇌경색의 한 원인이며, 선행된 외상 후 발생하는 경우가 흔해 두개강 내 보다는 두개강 외에 발생하는 경우가 많다. 건선은 흔한 피부 질환 중 하나이며, 서양인에 비해 동양인에서는 그 빈도가 낮고 다른 전신 질환과 동반되어 보고되기도 한다. 건선은 혈전 색전증과 연관된 허혈성 심뇌혈관계 질환과 연관되어 보고된 바가 있기는 하지만, 혈관 박리와 연관되어 보고된 경우는 드물다. 저자들은 이전에 건선으로 치료 받고 최근 피부 증상이 악화되던 중 우측 반신 마비와 안면 마비가 발생해 내원한 13세 여아에서 자발성 두개강 내 내경 동맥 박리를 진단하여 보고하는 바이다.

• Journal of Korean Neurosurgical Society
• /
• 제30권3호
• /
• pp.389-394
• /
• 2001

경막정맥동 혈전증은 다양한 원인을 가진 비교적 드문 질환으로 알려져왔으며 임상양상 및 발현형태가 매우 다양하여 임상적 진단이 쉽지 않았다. 그러나 최근에는 여러 영상진단 방법, 특히 자기공명영상 혈관 촬영등을 통해 조기 진단이 가능하게되었다. 치료 방법을 결정할 때, 환자의 임상증상과 정맥순환계의 개인간 차이가 매우 중요한 인자중 하나이다. 저자들은 보존적 치료로 좋은 결과를 얻은 2례의 경막정맥동 환자의 특성을 문헌고찰과 함께 보고하는 바이다.

• Journal of Korean Neurosurgical Society
• /
• 제45권1호
• /
• pp.5-10
• /
• 2009

Objective : Direct surgical clipping of paraclinoid aneurysms poses technical challenges to even very experienced neurosurgeons, making endovascular treatment an alternative treatment modality in many centers. We have therefore retrospectively evaluated the safety and efficacy of endovascular detachable coil embolization of paraclinoid aneurysms. Methods : From June 1997 to June 2007, 65 patients underwent endovascular detachable coiling for 67 paraclinoid aneurysms (of which 9 were ruptured and 58 were unruptured) in our institute. Their medical records, radiological images and readings, and operation records were reviewed retrospectively. Results : After the initial embolization procedure, complete occlusion was achieved in 29 (43.3%) of the aneurysms treated by endovascular detachable coiling. Six aneurysms required retreatment, with two each requiring one, two, or three additional endovascular procedures. Fifty-five (82.1%) aneurysms were measured by three-dimensional time of flight (TOF) magnetic resonance images (MRI) or transfemoral cerebral angiography (TFCA) at a mean follow-up of 29.7 months (range from 4 to 94 months), with 39 aneurysms (70.9%) showing complete occlusion. Thromboembolic events (3.8%) were the most frequent complication. Rupture did not occur during or after any of the procedures. According to the Glasgow Outcome Scale (GOS), 98.4% of the patients treated by coil embolization had a score of 4 or 5. Conclusion : Our results indicate that endovascular detachable coiling is a safe and effective treatment modality in paraclinoid aneurysms.

• Asian Pacific Journal of Cancer Prevention
• /
• 제17권12호
• /
• pp.5281-5285
• /
• 2016

Background: Brachytherapy is the most commonly used conservative treatment for the uveal melanoma. The aim of this study was to evaluate therapeutic results of Ruthenium-106 plaque brachytherapy in the management of localized uveal melanoma cases. Methods: We reviewed retrospectively the clinical records of all patients treated in our department for an uveal melanoma, undergoing Ruthenium-106 plaque brachytherapy, from January 1996 to December 2015. We focused on clinical features, therapeutic characteristics, local and distant tumor control and side effects. Results: Nineteen patients were enrolled in our study. Mean age was 56.2 years (28-79) and the sex ratio was 1.37:1 males to females. Diagnosis was made on the basis of ophthalmological clinical examination, angiography, ultrasound and/or magnetic resonance. Median tumor diameter was 9.7 mm (6-13) and median thickness 4.4 mm (2.5-8). The dose of Ruthenium-106 plaque brachytherapy prescribed to the apex of each tumor was 70 Gy in all cases. The median radiation dose to the sclera surface was 226.4 Gy (range: 179.6-342.3) and the median total application time 115.2 hours (range: 27 to 237). After a median follow-up of 61.5 months, local control was achieved in 17 patients (89%): 16 demonstrated a partial tumor response and 1 tumor stabilization. Two patients suffered local progression leading to enucleation, one dying of hepatic metastasis. Radiation-induced complications were cataracts in 3 cases and vitreal hemorrhage in 2. Conclusion: Ruthenium-106 plaque brachytherapy is an efficient treatment for localized uveal melanoma, offering good local control with low toxicity.

• Journal of Chest Surgery
• /
• 제48권3호
• /
• pp.187-192
• /
• 2015

Background: Aortic occlusion is rare catastophic pathology with high rates of mortality and severe morbidity. In this study, we aimed to share our experience in the management of aortic occlusion and to assess the outcomes of extra-anatomic bypass procedures. Methods: Eighteen patients who had undergone extra-anatomic bypass interventions in the cardiovascular surgery department of our tertiary care center between July 2009 and May 2013 were retrospectively evaluated. All patients were preoperatively assessed with angiograms (conventional, computed tomography, or magnetic resonance angiography) and Doppler ultrasonography. Operations consisted of bilateral femoral thromboembolectomy, axillo-bifemoral extra-anatomic bypass and femoropopliteal bypass and were performed on an emergency basis. Results: In all patients during early postoperative period successful revascularization outcomes were obtained; however, one of these operated patients died on the 10th postoperative due to multiorgan failure. The patients were followed up for a mean duration of $21.2{\pm}9.4$ months (range, 6 to 36 months). Amputation was not warranted for any patient during postoperative follow-up.. Conclusion: To conclude, acute aortic occlusion is a rare but devastating event and is linked with substantial morbidity and mortality in spite of the recent advances in critical care and vascular surgery. Our results have shown that these hazardous outcomes may be minimized and better rates of graft patency may be achieved with extra-anatomic bypass techniques tailored according to the patient.

• 대한핵의학회지
• /
• 제39권2호
• /
• pp.94-99
• /
• 2005

Electrocardiogram-gated single photon omission computed tomography (SPECT) provides valuable information in the assessment of both myocardial perfusion and ventricular function. Tl-201 is a suboptimal isotope for gating. Tl-201 images are more blurred compared with Tc-99m tracers due to the increased amount of scattered photons and use of a smooth filter. The average myocardial count densities are approximately one-half those of conventional technetium tracers. However, Tl-201 is still widely used because of its well-established utility for assessing myocardial perfusion, viability and risk stratification. Gated SPECT with Tl-201 enables us to assess both post-stress and rest left ventricular volume and function. Previous studies with gated Tl-201 SPECT measurements of ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV) have shown high correlation with first-pass radionuclide angiography, gated blood pool scan, Tc-99m-MIBI gated SPECT, contrast ventriculography, echocardiography, and 3-dimensional magnetic resonance imaging. However, problems related to these studies include few agreement data of EDV and ESV, use of a reference method that is likely to have the same systemic errors (gated Tc-99m-MIBI SPECT), and other technical factors related to the count density of gated SPECT. With optimization of gated imaging protocols and more validation studies, gated Tl-201 SPECT would be an accurate method to provide perfusion and function information in patients with coronary artery disease.

• Archives of Plastic Surgery
• /
• 제39권4호
• /
• pp.345-351
• /
• 2012

Background Cranial base defects are challenging to reconstruct without serious complications. Although free tissue transfer has been used widely and efficiently, it still has the limitation of requiring a long operation time along with the burden of microanastomosis and donor site morbidity. We propose using a reverse temporalis muscle flap and calvarial bone graft as an alternative option to a free flap for anterior cranial base reconstruction. Methods Between April 2009 and February 2012, cranial base reconstructions using an autologous calvarial split bone graft combined with a reverse temporalis muscle flap were performed in five patients. Medical records were retrospectively analyzed and postoperative computed tomography scans, magnetic resonance imaging, and angiography findings were examined to evaluate graft survival and flap viability. Results The mean follow-up period was 11.8 months and the mean operation time for reconstruction was $8.4{\pm}3.36$ hours. The defects involved the anterior cranial base, including the orbital roof and the frontal and ethmoidal sinus. All reconstructions were successful. Viable flap vascularity and bone survival were observed. There were no serious complications except for acceptable donor site depressions, which were easily corrected with minor procedures. Conclusions The reverse temporalis muscle flap could provide sufficient bulkiness to fill dead space and sufficient vascularity to endure infection. The calvarial bone graft provides a rigid framework, which is critical for maintaining the cranial base structure. Combined anterior cranial base reconstruction with a reverse temporalis muscle flap and calvarial bone graft could be a viable alternative to free tissue transfer.

• 대한방사선기술학회지:방사선기술과학
• /
• 제30권3호
• /
• pp.265-270
• /
• 2007

뇌경색환자들에 있어서 CE-TOF-MRA에서 MT 펄스사용의 유용성을 알아보고자 하였다. 2007년 5월에서 6월까지 뇌경색 증상 발현 후 최소 4시간에서 최대 5일 이내에 환자 10명을 대상으로 3Tesla 자기공명영상기기를 사용하여 조영제 주입 후 offset frequency 0, 600, 1,200, 1,800 Hz의 MT 펄스를 사용한 CE-TOF-MRA을 획득하였다. TOF-SPGR기법인 CE-TOF-MRA영상에서 정상혈관의 경우 SNR이 감소되었지만 CNR은 증가를 보였다. 좁아진 혈관부위는 MT 펄스 600 Hz, 1,200 Hz에서 최고의 CNR을 보였고, 협착된 혈관에서는 MT 펄스 강도와 비례하여 CNR이 증가 하였다. 혈관이 폐색된 경우에는 폐색범위가 명확하게 나타났고 MT 펄스 1,800 Hz에서 최고의 CNR로 평가되었다. 좁아지거나 보이지 않는 혈관에서는 형태변화가 없었고, 혈관이 폐색되어 평가가 불가능한 혈관에서 MT 펄스 후 혈관과 배후조직 SNR은 다소 감소하였지만 두 조직간 CNR은 증가되었다.