对比剂浓度递减不用压迫带MSCT静脉成像的临床应用

目的：探讨对比剂浓度递减不用压迫带MSCT静脉成像的临床应用价值。方法-对151例下肢静脉曲张和／或下肢肿胀患者采用不用压迫带绑扎下肢法，直接在足背或内外踝部静脉以2ml／s流率注射稀释对比剂，采用双筒双流高压注射器双筒双流连续注入稀释对比剂360-80ml，浓度从12％递减至5％，注射至半量时（约90s）行Ⅰ期扫描，对比剂剩余约30ml时（约170s）行Ⅱ期扫描。从两期横轴面图像结合曲面重建、VR和MIP后处理图像，观察静脉曲张程度，对比剂滞留，静脉瓣的关闭状态，静脉血管有无中断、狭窄、压迫、充盈缺损和侧支循环。动态分析股静脉至下腔静脉内充盈缺损的密度和形态，判断其是否为血栓并与分流、边流、涡流相鉴别。结果：下肢静脉曲张无深静脉血栓92例；下肢静脉曲张合并深静脉血栓28例；下肢静脉曲张合并对比剂滞留69例；静脉瓣膜功能不全21例；下肢深静脉血栓合并深浅静脉侧支回流17例；髂总静脉压迫综合征3例；髂总静脉口膜性狭窄1例；髂静脉扁细狭窄3例；股静脉转移瘤浸润致血管阻塞2例；下肢增粗软组织肿胀但静脉血管未见异常4例；下肢静脉和软组织未见异常1例。结论：对比剂浓度递减不用压迫带绑扎法下肢MSCT静脉成像能较好显示下肢深浅静脉，尤其是股静脉至下腔静脉血管的形态和病变，为临床提供可靠的影像学诊断依据。

Clinical application of direct MSCT venography of lower extremity with reduced concentration of contrast medium and without tourniquet

Objective：To explore the clinical application of MSCT venography of lower extremity with reduced con centration of contrast medium and without tourniquet. Methods： Direct MSCT venography of lower extremity with reduced concentration of contrast medium and without tourniquet was performed in 151 patients with varicous vein or limb swelling. Superficial vein on the dorsum of foot or at internal or external ankle was punctured. A total amount of 360-380ml contrast medium （12%-5%） was injected in 2ml/s injection rate using a double syringe and double flow injector （MADRER, USA）. Axial amages conblined with images from post-processing techniques （CPR, VR, MIT） were obtained. Severity of varices, retention of contrast medium,narrowing or occlusion of the veins were observed. Dynamic dual-phase scanning was performed for detection of thrombosis, split flow,edge flow and terbulent flow. Results：All the examinations were satisfac-tory except failure of punture in six cases. The puncture failed at one side in 5 cases of bilateral lesions. There were varicous veins without thrombosis in 92 cases and with thrombosis in 28 cases, venous valve infufficiency in 21 cases, deep vein thrombosis with collaterals in 17 cases and other anomalies in 13 cases. In one cse no abnormal changes were found. Conclu-sions： Direct MSCT venography of lower extremity with reduced concentration of contrast medium and without tournequet is a good method to show the morphlolgy and lesions of supercicial as well as deep veins, especially the femoral vein and inferi-or vena cava. It can provide reliable imaging evidence for clinical diagnosis.