[自然科学]常规数字化影像设备介绍.pptVIP

* Digital Density Optimization (DDO)* 防烧灼功能 对数字图像进行曝光密度补偿 可实时和后处理进行 *Option without DDO with DDO 先进的软件处理 * * As a rule a shunt is placed between the arm artery and vein to perform dialysis (when the kidneys are not functional any more). This is required for dialysis for taking blood and returning the washed blood to the body. Thus, the time needed for the dialysis is being reduced (due to higher flow rates). In the images displayed, dilatation of a constriction at the shunt has been performed successfully. * X-ray images are so-called summation images. The different types of tissue differ scarcely in the normal X-ray image. Blood and blood vessels are also normally not visible. The different types of tissue as well as blood vessels can be distinguished only in MR images (magnetic resonance). Differentiation is also possible in CT (computed tomography), but not as good as in MR. Vessels are also not visible in this case without contrast medium.(Blood can be displayed in the CT image only in the case of fresh hemorrhages.) For diagnostic radiology and angiography the organs to be assessed must therefore be visualized in each case with an adequate contrast medium. * * 腹部血管 * 治疗显示分流 – 扩张 * 介入-治疗动脉瘤 大的颅内动脉瘤 用线圈硬化 * * 介入治疗-阻塞血管 栓塞 人工阻塞血管治疗, 肿瘤血供, 动静脉畸形, 或颅内动脉瘤 白金螺圈 粘合剂 酒精 AVM = arterial-venous-malformationshortcut (shunt) between arteries and veins * 介入-动静脉畸形栓塞 Situation before intervention embolization material is injected via microcatheter Result after Embolization display of the embolization material in the native image * 介入-治疗动脉瘤 Aneurysms are additional lumen (?bags“) in arteries congenital or induced by an accident * 介入-动脉瘤支架 * 介入治疗-预防栓塞 管腔过滤 a little ?umbrella“ is placed in the vena cava to ?collect“ thrombs before they reach the pulmonary circulations and could cause a lung embolie * 原理和技术应用核医学 核医学（Nuclear Medicine） 单光子发射CT(SPECT、Single Photon Emission Computed Tomography ) 正电子发射CT(PET、Positron Emission Tomography)，可生成功能影像。 * 原理