引言造影剂在许多放射诊断过程中是最重要的技术要素之一。在早期的放射学历史上人们用重金属盐来显示血管系统,但这些物质有毒不适用于病人。本世纪二十年代一种无机碘——碘化钠被广泛地用于血管造影,但应用高浓度时它是有毒的。1929年第一种有机碘——Selectan 被用于静脉尿路造影,接着其它几种有机碘迅速用于临床,提纯有机碘产生的造影剂在显像技术如血管造影方面是相对 Introduction Contrast media is one of the most important technical elements in many diagnostic radiologies. In the early history of radiology people used heavy metal salts to show the vascular system, but these substances were not toxic to the patient. An inorganic iodine-sodium iodide is widely used in angiography in the 1920s, but toxic at high concentrations. In 1929 the first organic iodine --Selectan was used for intravenous urography, followed by several other organic iodine quickly used in clinical, purifying organic iodine contrast medium in imaging techniques such as angiography is relative