分析原发性静脉平滑肌肿瘤的多模态声像图特征，以提高对该类疾病的认识，减少误诊。

收集2010年1月至2016年1月在四川大学华西医院就诊的经病理证实为原发性静脉肿瘤的患者9例，其中静脉平滑肌瘤6例，平滑肌肉瘤3例。采用高分辨率灰阶超声检查在横切面及纵切面显示病变部位及大小，观察受累静脉是否增粗；采用多普勒超声观察静脉病变内有无动脉血流信号；注射超声造影剂声诺维2.4 ml后观察静脉内肿块的强化模式。

本组平滑肌瘤患者6例，其中前臂头静脉3例，颈外静脉2例，右侧髂内静脉平滑肌瘤经下腔静脉延伸至右心房1例。4例静脉管径增粗；全部病例管腔内弱回声充填；彩色血流成像显示3例平滑肌瘤内部可见较丰富的动脉血流信号；所有平滑肌瘤在动脉期呈均匀高增强，静脉期呈较均匀低增强。本组3例髂-股静脉平滑肌肉瘤。静脉管径增粗呈瘤样扩张；管腔内查见不均质弱回声完全性充填；肿块内部可见较丰富的动脉血流信号；肿块在动脉期呈不均匀高增强，静脉期呈不均匀低增强，2例肿块内可见片状不强化区。

静脉管径增粗对原发性静脉平滑肌肿瘤有"预警"作用；肿块内动脉血流信号对静脉肿瘤的诊断有重要价值；超声造影对鉴别血栓与肿瘤有决定性意义。

To evaluate the features of primary smooth muscle tumor originating from venous system based on the multimodal ultrasonographic images, and further to enhance the understanding of this entity with less misdiagnosis.

A total of nine patients with smooth muscle tumor, who referred to our hospital between January 2010 and January 2016, were enrolled in this study. Diagnosis was made by histopathologic findings, including 6 cases of leiomyoma and 3 cases of leiomyosarcoma. High-resolution gray-scale ultrasonography was used to assess the location and size of the tumor, as well as to identify whether the involved vein dilated or not. Doppler ultrasonography was used to detect the arterial blood flow signals in the tumor. SonoVue was injected to evaluate the enhancement mode of the tumor.

Among the 9 patients, there were 6 patients with leiomyoma, of which 3 cases involving cephalic vein, 2 cases involving external jugular vein and 1 case involving internal iliac vein (extend to right atrium through inferior vena cava). Hypo-echoic mass was demonstrated in all cases, and venous dilation was found in 4 cases. Abundant arterial blood flow signals were detected in 3 cases by Doppler ultrasonography. All the tumors presented with high-level of enhancement in the arterial phase and low-level enhancement in the venous phase. In addition, there were 3 patients with leiomyosarcoma involving femoral vein or iliac vein. The characteristics of leiomyosarcoma including aneurismal dilation of the involved vein, inhomogeneous mass with hypo-echoic signals, abundant arterial blood flow signals and leiomyosarcoma-liked enhancement mode. However, there were 2 patients presented with regional non-enhancement mode.

We concluded that venous dilation may be a useful clue for the diagnosis of primary smooth muscle tumor originating from venous system. An arterial blood flow signal is an important feature of this lesion. Ultrasonography can be utilized to differentiate between tumor and thrombus.