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ABSTRACT: Purpose : To evaluate intracranial hemodynamic stabilization patterns after carotid artery stenting (CAS) in patients having variable collateral developments before CAS. Methods : The hemodynamic and angiographic data of 62 patients (58 men; mean age 68.0±8.4 years) who underwent CAS for unilateral proximal internal carotid artery stenosis were analyzed. The patients had transcranial Doppler examinations before and at 1 and 90 days after CAS. Patients were classified according to pre-CAS mean blood flow velocity (MBFV) of the ipsilateral middle cerebral artery (MCA): low (<30 cm/s; n=17), normal (30 to 48 cm/s; n=26), or high (>48 cm/s; n=19). The collaterals from contralateral anterior and/or posterior circulations prior to CAS, the stabilization pattern of MBFV, and the pulsatility index (PI) after CAS were compared across the 3 groups. Results : The presence of collaterals was lowest in the low MBFV group (17.6% of patients) than in the normal (38.5%) or high (68.4%) MBFV groups (p=0.008). The low MBFV group exhibited an increase in MBFV and PI in the ipsilateral MCA at 1 and 90 days after CAS (p<0.05). By contrast, the high MBFV group exhibited a decrease in MBFV and no change in PI in the ipsilateral MCA up to 90 days after CAS (p<0.05). The normal MBFV group showed an increase in MBFV at post-CAS day 1 but a subsequent decrease at 90 days and an increase in PI in the ipsilateral MCA at 1 and 90 days post-CAS (p<0.05). Conclusion : The pattern of post-CAS intracranial hemodynamic stabilization differs according to the pre-CAS MBFV in the ipsilateral MCA.
Journal of Endovascular Therapy 05/2013; 20(3):398-405. · 2.86 Impact Factor
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ABSTRACT: We report herein a case successful endovascular treatment with a stent-graft of a rare case of rapidly growing mycotic aneurysm of the left common carotid artery due to acute bacterial endocarditis after eradication of the infection. Infected mycotic aneurysms of the peripheral vasculature have been considered as a contraindication for stent-graft implantation because of the possibility of microorganism spreading to the stent-graft; however, if there is evidence of complete eradication of microorganism and surgery is not an option, stent-graft implantation can be an effective and safe treatment modality for exclusion of the mycotic aneurysm.
Yonsei medical journal 01/2012; 53(1):224-7. · 0.77 Impact Factor
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ABSTRACT: Acutely aggravated dissecting flap and consequent occlusion of the superior mesenteric artery (SMA) by simple contrast passage during initial angiography for percutaneous stent placement is a uncommon event, which usually is not reported. After analysis of many factors that underlie development of such complications, we present herein one case of successful treatment of isolated SMA dissection and its complications with favorable outcomes during 25 months follow-up after percutaneous stent placement.
Yonsei medical journal 09/2011; 52(5):859-62. · 0.77 Impact Factor
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ABSTRACT: Prompt revascularization of the superior mesenteric artery (SMA) thrombotic occlusion can prevent intestinal infarction and decrease necrosis of the bowel segment. Herein, we describe two cases who underwent successful endovascular recanalization for acute SMA thrombosis using a primary aspiration thrombectomy because of possible consequent laparotomy for survey of bowel viability. The two patients had dramatic pain relief immediately after the procedure and remained symptom-free during the follow-up period.
World Journal of Gastroenterology 08/2010; 16(32):4112-4. · 2.47 Impact Factor
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ABSTRACT: This randomized, double-blind, placebo-controlled study was conducted to examine the preventive effect of nafamostat mesilate, a kallikrein inhibitor, on the withdrawal response associated with rocuronium injection.
Ninety American Society of Anesthesiology (ASA) physical status I or II patients, aged 18-65 years, were randomly divided into two groups that received either a 1.5-ml solution containing 1.5 mg nafamostat mesilate diluted in a 5% glucose solution or a 1.5-ml 5% glucose solution. Anesthesia was induced by 5 mg/kg 2.5% thiopental. After confirming loss of consciousness, a tourniquet was applied to the mid forearm and tightened to block venous flow. The test solution was then administered, 1 min after which the tourniquet was removed and 0.6 mg/kg rocuronium was administered. Each patient's response to rocuronium injection was graded on a four-point scale in a double-blind manner. Activated coagulation time and plasma potassium concentration were measured before and 5 and 10 min after nafamostat administration.
The incidence of withdrawal response was 68.9% in the control group and 24.4% in the nafamostat group (P < 0.001). The number of patients showing generalized movement (response 4) with the rocuronium injection was significantly lower in nafamostat group [1 (2.2%)] than the control group [15 (33.3%)], P < 0.001. Five and 10 min after nafamostat administration, measured potassium and activated coagulation time were similar to baseline values.
Pretreatment with 1.5 mg nafamostat mesilate decreased withdrawal response associated with rocuronium injection.
Journal of Anesthesia 05/2010; 24(4):549-52. · 0.83 Impact Factor
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ABSTRACT: This study evaluated the changes in blood flow velocity in the anterior and posterior intracranial circulations according to the progression of moyamoya disease in adult patients.
We evaluated Suzuki's angiographic stage and mean blood flow velocity (MBFV) changes in intracranial vessels from both sides in 19 adult moyamoya patients. We then analyzed the linearity of MBFV changes from early to late moyamoya stages in each intracranial vessel using piecewise linear regression models.
The MBFV in the middle cerebral artery, terminal internal carotid artery, and anterior cerebral artery increased non linearly until stage III, and then decreased progressively up to stage VI. The ophthalmic artery also showed nonlinear velocity changes, with an increase in MBFV up to stage IV, followed by a decrease in MBFV up to stage VI. The MBFV of the basilar artery increased linearly from a normal velocity at an early moyamoya stage to a stenotic velocity at a late stage. There was no statistically significant regression model for the relationship between the MBFV in the posterior cerebral artery and moyamoya stage.
The nonlinear and/or linear MBFV changes associated with variable intracranial vessels might be useful in initial and follow-up evaluations of different stages of moyamoya disease.
Journal of Clinical Neurology 07/2008; 4(2):67-74. · 1.69 Impact Factor
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ABSTRACT: The network model for two-class pattern classification originally
proposed by C. Koutsougeras and C.A. Papachristou (1988) is extended to
n -class pattern classification. The proposed model has the
advantage of expanding the network by adding the units during the
partitioning of the input space while other models have the network
topology specified. The result is compared with that of ID3, which is
known as a knowledge acquisition tool in machine learning. The
comparison shows that the proposed model leads to a better correct rate.
This improvement might result from the additional consideration of the
optimal projection direction, which ID3 does not consider
Neural Networks, 1992. IJCNN., International Joint Conference on; 07/1992