血管DSA中路图图像质量控制的研究

Research about quality control of roadmap image during digital subtraction angiography

目的解决在腹部出现的血管DSA路图图像中影响诊断和治疗的图像质量问题,主要包括血管失真、边缘模糊、背景减影程度不够、成像区域中过饱和、注入药物路图不清晰等情况。方法组1肝癌患者30例,其中男性23例,女性7例;年龄32～65岁,平均年龄51岁。组2肝癌患者30例,其中男性18例,女性12例;年龄27～54岁,平均年龄48岁。组1采用调整前造影方案。针对肝癌的患者DSA过程中的路图图像,分析影响其质量下降的因素,并对这些因素进行调整,用于组2造影。具体包括路图中透视图像血管图像叠加的数量由3调整为1、实时背景衰减因素由1.4调整为1.0、透视减影增益步长由14调整为11、整体图像的亮度由0.63调整为0.76、对比度由1.00调整为0.94等,同时请3位介入临床医生评价调整后的图像质量,达到满意为止。结果组1患者30例中,路图图像质量优0例(0%),良6例(20%),差24例(80%);组2病例中,优27例(90%),良3例(10%),差0例(0%)。调整的这些参数确实使路图图像得到了改善,调整后的路图图像血管清晰、边缘清楚及背景、亮度、对比度、成像区域过饱和情况得到改善,图像能够满足医生的诊断和治疗要求。结论由于在腹部特别是横膈附近运动幅度比较大,原先预置的与路图相关参数不能满足临床图像要求,这些参数的调整解决了路图图像质量的问题,达到了临床诊断的要求。

Objective To solve the problem of image quality effects in diagnosis and treatment of abdominal vascular DSA, including vascular distortion, inadequate level of edge blur, less background subtraction, super-saturation in imaging area, bad drug injected roadmap image, and etc. Methods Thirty patients with hepatic carcinoma were in group 1, male 23, female 7, aged 32 - 65 years old, mean age 51. Thirty patients with hepatic carcinoma were in group 2, male 18, female 12, aged 27 - 54 years old, mean age 48 years old. The factors influencing roadmap image quality of hepatic carcinoma treatment using DSA were analyzed and adjusted, such as vascular roadmap image integration number（adjusted to 3 - 1）, background subtraction fade for live（adjusted to 1.4 - 1.0）, fluoroscopy subtraction gain step（adjusted to 14 - 11）, brightness（adjusted to 0.63 - 0.76） and contrast（adjusted to 1.00 - 0.94） of image, and etc. Three interventional clinicians were invited to evaluate adjusted image quality until the images were gratified. Results No excellent images were observed in group 1, the moderate were 6（20 %）, bad were 24（80 %）. In group 2, excellent images were 27 （90 %）, the moderate were 3 （10 %）, and no bad images. The adjusted parameters improved the roadmap image, and adjusted image showed characteristic of clear edge, proper background subtraction fade, proper brightness and contrast, improved saturation, and improved images was satisfied the diagnosis and treatment requirements of the doctor. Conclusion It is demonstrated that as movement range of the abdomen, especially near the diaphragm, is relatively large, originally associated with a roadmap of preset parameters could not meet the clinical imaging requirements. Adjusting the parameter can solves the problem of roadmap image quality, and meets the requirements of the clinical diagnosis.