MDCT双期扫描及后处理重建在肾静脉异常中的应用价值

Biphasic scanning and postprocessing reconstruction images with MDCT: clinical significance in evaluating renal vein abnormalities

目的:探讨多排螺旋CT(MDCT)双期扫描及图像后处理重建方法在肾静脉异常中的应用价值。材料和方法:回顾性分析18例肾静脉异常患者(肾静脉变异3例,肾静脉栓子9例,左肾静脉压迫综合征3例,脾肾静脉分流、动静脉瘘和静脉瘤各1例)的MDCT图像,比较MDCT双期扫描及各种图像后处理重建方法对肾静脉异常的显示效果。结果:①MDCT双期扫描图像可清晰显示肾静脉及其伴随病变;动脉期图像可对所有肾静脉异常作出初步诊断,静脉期图像显示肾静脉属支、侧支循环交通支静脉、静脉栓子范围及伴随的静脉系统异常较动脉期图像更有优势。②MPR图像可清晰显示肾静脉腔内外情况及合并的静脉周围组织病变,但难以完整显示血管解剖全貌;CPR可将迂曲的肾静脉拉直显示,但造成周围解剖结构分离、变形;MIP对血管解剖及病灶的显示效果最佳,薄块MIP能减轻图像重叠的干扰;VR显示肾静脉解剖形态立体感强,对重叠血管和动静脉畸形的显示优于MIP,但不能显示静脉腔内栓子。结论:MDCT双期扫描结合适当的后处理重建方法可以满意显示肾静脉解剖及病变,是评价各种肾静脉异常及伴随病变的准确、安全方法。

Objective： To investigate the clinical significance of biphasic scanning and postprocessing reconstruction images with MDCT in evaluating renal vein abnormalities. Materials and Methods： Eighteen cases with renal vein abnormalities on MDCT were analyzed retrospectively, which included renal vein variations in 3 cases, venous thrombi in 9 cases, left renal vein entrapment syndromes in 3 cases, splenorenal shunt, arteriovenous fistula and vein aneurysm in each case respectively. The ability to display renal vein abnormalities on biphasic scanning and all kinds of postprocessing reconstruction images were compared. Results： ①Renal vein abnormalities and concomitant lesions were clearly displayed on biphasic scanning images of MDCT. All renal vein abnormalities could be found preliminarily on arterial phase images. Renal vein tributaries, collateral vessels, tumor thrombus and associated abnormalities of venous system could be more predominant on venous phase images than those on arterial phase images. ②The information Of exterior and interior to the lumen of vein could be displayed clearly on MPR, but whole vessel anatomy could not be manifested. Circuitous renal vein could be spread on CPR, but adjacent structures were also deformed. Renal vein anatomy and lesion were showed best on MIP, and especially thin-slab MIP had the advantage to decrease image overlap. VR had strong ability to display vessel configurations and was better than MIP at displaying overlapping vessels and arteriovenous malformations, but it could not show venous thrombosis. Conclusion： Biphasic scanning and appropriate postprocessing reconstruction methods on MDCT could demonstrate the renal vein anatomy and lesion satisfactorily and might be an accurate and safe method to evaluate renal vein abnormalities and concomitant lesions.