目的:明确脊柱骨巨细胞瘤的多层螺旋CT、MRI表现。方法:回顾性分析经病理证实的脊柱骨巨细胞瘤6例(男5例,女1例,年龄21～40岁,平均32岁)。6例CT检查,3例有MRI检查。结果:发生于胸椎3例,腰椎1例,骶椎2例。CT主要表现为膨胀性溶骨性破坏和较大软组织肿块;MRI表现T1加权成像为低等信号,T2加权成像为高低混杂信号特点,可显示瘤内坏死、囊变、出血等。结论:脊柱骨巨细胞瘤具有侵袭性强、生长活跃、易复发等特点,结合CT、MRI检查可对该病做出及时诊断,且对临床分期、手术方案制订及术后定期随访有重要价值。
Numerical simulation of stent deployment is very important to the surgical planning and risk assess of the interventional treatment for the cardio-cerebrovascular diseases. Our group developed a framework to deploy the braided stent and the stent graft virtually by finite element simulation. By using the framework, the whole process of the deployment of the flow diverter to treat a cerebral aneurysm was simulated, and the deformation of the parent artery and the distributions of the stress in the parent artery wall were investigated. The results provided some information to improve the intervention of cerebral aneurysm and optimize the design of the flow diverter. Furthermore, the whole process of the deployment of the stent graft to treat an aortic dissection was simulated, and the distributions of the stress in the aortic wall were investigated when the different oversize ratio of the stent graft was selected. The simulation results proved that the maximum stress located at the position where the bare metal ring touched the artery wall. The results also can be applied to improve the intervention of the aortic dissection and the design of the stent graft.
ObjectiveTo analyze the causes and preventions of stent graft induced new entry (SINE) after thoracic endovascular aortic repair (TEVAR) for Stanford type B dissection, particularly from the standpoint of biomechanical behavior of stent graft. MethodsSINE was defined as the new tear caused by the stent graft itself, excluding those arising from natural disease progression or any iatrogenic injury from the endovascular manipulation. Twentytwo patients with SINE were retrospectively collected and analyzed out of 650 cases undergoing TEVAR for type B dissection from August 2000 to June 2008 in our center. An additional case included was referred to our center in 14 months after TEVAR performed in another hospital. ResultsTotally, there were 24 SINEs found in 23 cases, including SINE at the proximal end in 15 cases, at the distal end in 7, and at both in 1, and 6 patients died. The incidence was 3.4% ( 22/650) in our hospital, and the mortality was 26.1% (6/23). All 16 proximal SINEs was located at the greater curve of the arch and caused retrograde type A dissection. All 8 distal SINEs occurred at the dissected flap, and 5 of them caused enlarging aneurysm while 3 remained stable. All 23 cases had the endograft placed across the distal aortic arch during the primary TEVAR. ConclusionsSINE is not rare following TEVAR for type B dissection, and associates with a high substantial mortality. The stress yielded by the endograft seems to play a predominant role in its occurrence. It is of significance to take the stressinduced injury into account during both design and placement of the endograft.