论文部分内容阅读
目的探讨64排螺旋CT在血液透析自体动静脉瘘狭窄中血管成像(CTA)的方法和体会。方法在让患者充分了解和愿意配合本检查后,使用64排螺旋CT。患者取俯卧位,患肢上举,高于头部,取健侧肘静脉穿刺,团注对比剂,最大不超过55 ml,流率4～5 ml/s。对比剂注射完毕后立即以相同流率注入20～30 ml生理盐水。CT扫描参数为:层厚0.625 mm,螺距为1.108,螺旋时间0.75 s/r,80 kV和120 mAs。采用自动管电流和Blous Track-ing扫描方式,对21例(男12例,女9例,中位年龄61岁)自体动静脉瘘狭窄的患者行CTA检查。在EBW工作站上采用1 mm层厚行矢、冠和轴位的重组,并进行三维的多平面重组(MPR),曲面重组(CPR),最大密度投影(MIP)和容积再现(VR)以最佳参数和角度显示自体动静脉瘘狭窄的状况。结果本组患者有20例(95%)获得了满意的CTA图像,即狭窄部位清晰可见,病变血管的范围、走行清楚。侧支循环血管清晰。本组21例均为血管超声所发现,其中10例被DSA或手术证实与CTA结果相同。结论要获得良好的自体动静脉瘘CT图像,需与患者良好的沟通,参数配置准确,恰当。其中对比剂的用量和扫描速度的快慢、扫描时间的长短,阈值的设定,为关键因素。
Objective To explore the method and experience of 64-slice spiral CT in the diagnosis of stenosis of hemodialysis arteriovenous fistula (CTA). Methods 64-slice spiral CT was used after patients were fully informed and willing to cooperate with this test. Patients take prone position, the limb lift, higher than the head, take the health side of the elbow venous puncture, bolus contrast group, the maximum does not exceed 55 ml, the flow rate of 4 ~ 5 ml / s. Contrast agent injection immediately after injection with the same flow rate of 20 to 30 ml of normal saline. The CT scan parameters were 0.625 mm layer thickness, 1.108 pitch, helix time 0.75 s / r, 80 kV and 120 mAs. Twenty-one patients (12 males and 9 females, with a median age of 61 years) with autologous arteriovenous fistula stenosis underwent CTA using automated tube current and Blous Track-ing scanning. In the EBW workstation, 1 mm slice thickness of the crown, the crown and the axis of the reorganization, and three-dimensional multi-plane reorganization (MPR), surface reconstruction (CPR), maximum density projection (MIP) and volume rendering Good parameters and angles show the status of autologous arteriovenous fistula stenosis. Results In this group of patients, 20 patients (95%) obtained satisfactory images of CTA, that is, the stenosis was clearly visible. The extent of the diseased vessels was clear. Collateral blood vessels clear. The group of 21 cases were found by vascular ultrasound, of which 10 cases were confirmed by DSA or surgery and CTA results the same. Conclusion To obtain a good CT image of autologous arteriovenous fistula, it needs good communication with patients and the parameter configuration is accurate and appropriate. The amount of contrast medium and the speed of the scan speed, the length of the scan time, the threshold setting, as the key factor.