髂静脉压迫综合征CT影像解剖基础及分型诊断

Underlying CT anatomy and subtype diagnosis of iliac vein compression syndrome

目的通过CT检查分析髂静脉压迫综合征（IVCS）的解剖基础及以此分型诊断的影像指标和临床意义。方法回顾分析69例IVCS患者的影像资料，根据CT表现，分为单纯型组（22例，髂静脉单纯由髂动脉在前方压迫）、腰椎退变相关型组（33例，除了髂动脉压迫，还合并下腰椎退行性改变如椎间盘膨凸等从后方嵌入性压迫髂静脉）和其他原因IVCS组（14例，脓肿或血肿）；同时选取69名腰椎CT表现正常者为对照组，两组问年龄和性别相匹配。评价指标包括发病年龄、病程、椎前髂静脉通道矢状径、下腰椎前曲度、腰椎退变压迫髂静脉征象、髂静脉压迫部位、栓塞范围及介入治疗效果。患者组与对照组及患者组内的年龄、椎前髂静脉通道矢状径及下腰椎前曲角的两两比较，应用单因素方差分析，Bofferroni检验对均数问的多重比较进行校正；患者各组间髂静脉压迫位置与深静脉栓塞范围的分布差异以及各组介入治疗效果的差异，应用交叉表X2检验。结果腰椎退变相关型IVCS组平均发病年龄（61．5±10．6）岁，单纯型（42．3±6．5）岁，其他原因组（53．1±16．8）岁，差异有统计学意义（F=11．030，P〈0．01）。退变型IVCS椎前髂静脉通道矢状径（2．3±0．5）mm，下腰椎前曲角（121．8±5．4）°；单纯型的分别为（2．5±0．5）mm，（124．4±3．9）°；其他原因组分别为（5．9＋2．3）mm和（129．5±5．9）°；对照组分别为（6．4±1．6）mm和（127．5±7.3）°。组间矢状径比较F=125．275，组间前曲角比较F=7．949，P值均〈0．01。腰椎退变相关型IVCS髂静脉受压位置位于腰5椎体正前方者占56％（18／33）、右前方和左前方者各占9％（3／33），腰4—5椎间盘正前方占26％（9／33）；而单纯型IVCS患者髂静脉受压位置位于腰5椎体右前方（64％，14／22）、正前方（18％，4／22）及腰4—5椎间盘正前方（18％，4／22），两组间位置分布差异有统计学意义（x2=19．305，P〈0．01）。退变型IVCS患者深静脉栓塞18％（6／33）限于髂静脉，30％（10／33）累及股静脉，52％（17／33）延及腘静脉；单纯型的栓塞范围全部超出髂静脉，27％（6／22）累及股静脉，73％（16／22）延及胴静脉；其他原因的患者30％（4／14）的栓塞范围限于髂静脉，40％（6／14）累及股静脉，30％（4／14）延及腘静脉，各组之间栓塞范嗣分布差异有统计学意义（x2=9．28，P〈0．01）。需要植入静脉支架治疗的单纯型IVCS患者为86％，腰椎退变相关型IVCS仅52％，其他原因者无需植入血管支架。结论CT可以准确地显示不同类型髂静脉压迫综合征患者的病理解剖特点，有利于指导临床制定有效的治疗方案。

Objective To explore the underlying anatomy of iliac vein compression syndrome （IVCS） using CT, and discuss the imageological index for subtype diagnosis and potential clinical significance. Methods We retrospectively analyzed the imageological data of 69 IVCS patients from July, 2009 to June, 2014. According to CT findings, patients were categorized to simple IVCS （sIVCS, the lilac vein is compressed by only the anterior iliac artery, n=22）, lumbar degeneration-related IVCS （ dIVCS, besides the iliac artery, the lower lumbar degenerative changes including osteophyte, protruded disc, etc. pressed the iliac vein from the back, n=33） and other IVCS causes （oIVCS, including tuberculosis, inflammation and fracture hematoma of the lumbar spine, n=14）; meanwhile, 69 age- and sex-matched subjects was set as a control group. Evaluated indexes were onset age, course of lower limb swelling and pain, size of the iliac vein tunnel ahead lumbar （IVTAL）, lower lumbar spine forward curvature angle （LLSCA）, iliac vein-pressed signs by lower lumbar degeneration, compression sites, scope of deep venous thrombosis and interventional therapeutic effect. The differences of those indexes of various groups were compared. Data as onset age, course of disease, sizes of IVTAL and LLSCA were evaluated using variance analysis of the general linear model, with Bofferroni test correction for multiple comparisons. Data as iliac vein-pressed site, scope of venous embolism and therapeutic effect were assessed by crossing table X2 test. All statistical analyses were performed using SPSS17.0 software （SPSS company, Chicago, USA）. Bilateral P〈0.05 were considered to be significant. Results The onset mean age was （61.5 ± 10.6） yr. in dlVCS, （42.3 ± 6.5） yr in sIVCS, and （53.1± 16.8） yr. in oIVCS with a significant difference （ F= 11.030, P〈0.01）. Mean sagittal diameter of the IVTAL and LLSCA were （2.3±0.5） mm and （ 121.8± 5.4）° in dlVCS and （2.5± 0.5） mm and （124.4±3.9）° in sIVCS, respectively; which were smaller than those of control group [（6.4± 1.6 ） mm and （ 127.5 ±7.3 ）°, respectively ] and olVC S [ （ 5.9±2.3 ） mm and （ 129.5 ± 5.9 ） °, respectively ] （F= 125.275, P〈0.01 for sigittal diameter and F=7.95, P〈0.01 for LLSCA）. The degenerative changes compressing the iliac vein of dIVCS had 41 sites of 33 patients which were respectively the discal forward protrusion or bulge （51%, 17/33）, vertebral anterior osteophyte （50%, 16/33）and lower lumbar vertebrae slippage （19% ,8/33）. The compression sites of dIVCS located exactly anterior to the fifth lumbar （18/33, 56%）, the intervertebral disk between the fourth and fifth lumbar（9/33, 26%）, the right front （3/33, 9%） and left front （3/33, 9%） of the fifth lumbar, however, that of sIVCS sited the right front （ 14/22, 64% ）, exactly the front （4/22, 18% ）of the fifth lumbar and exactly anterior （4/22, 18% ）to the intervertebral disk between the fourth and fifth lumbar, with a significant difference of location distribution （X2=19.305, P〈0.01）. In sIVCSs, deep vein thrombosis of all exceeded the iliac vein length and implicated the femoral vein by 27% （6/22） and the popliteal vein by 73% （16/22）, while in dIVCSs 18% （6/33）patients had deep vein thrombosis in the iliac vein, 30% （10/33）in the femoral vein and 52% （17/33）in the popliteal vein, and in oIVCSs, 30% （4/14）patients had deep vein thrombosis in the iliac vein, 40% （6/14）in the femoral vein and 30% （4/14）in the popliteal vein, with a significant difference of thrombosis scope （X%9.28, P〈0.01）. 86% sIVCSs needed intravenous stent-implanted operation to obtain effective treatment, only 52% dlVCSs were performed stent-implanted operation for effective therapy, none of oIVCSs had stent-implanted operation before the iliac vein recanalization. Conclusion CT can precisely display the pathological anatomy features of different IVCS patients, which can potentially help clinicians plan accurate treatment strategy.