摘要
目的探讨能谱成像技术(GSI)去除碘对比剂硬化伪影方面的价值,并评估CT值测量的可靠性。方法将碘剂与水配成18种浓度(0～100.0g/L)的试管液,并分别在离体及模型内行GSI和常规140kVp两种成像扫描。测量试管内外兴趣区不同条件下不同扫描方式图像的CT值和SD值,计算兴趣区的伪影指数(AI)并进行对比分析;在0和100.0g/L试管周围取多个兴趣区,测量CT值,计算伪影造成的CT值偏差并进行对比分析。结果 70及80keV单能量图像的AI值与140kVp图像的AI值比较,差异有显著性(t=5.208、3.583,P<0.01),80keV图像质量更优;80keV图像下碘剂周围组织CT值偏差小于140kVp图像(t=3.804,P<0.01);80keV图像中各碘管离体和载体之间CT值偏差小于140kVp图像。结论 GSI有助于解决碘对比剂引起的硬化伪影,提高血管造影检查的图像质量,并对血管周围组织定量分析。
Objective To assess the value of energy-spectrum imaging technique（ESIT） in removal of beam hardening artifact（BHA） due to iodated contrast agent,and the reliability of the values measured by CT. Methods A test-tube solution of 18 different concentrations（0-100.0 g/L） was constituted by iodine and water,which were scanned,in vitro and within the model,separately（ESIT;140 kVp）.The CT and SD values of image scanned of the interior and exterior regions of interest of test tubes under different conditions and different scan modes were measured,the artifact index（AI） of the regions of interest was calculated and analyzed.Several regions of interest around the test tubes（0-100.0 g/L） were detected for CT values,the deviation of the values due to artifacts was accounted and analyzed. Results The AI of 70 keV and 80 keV were lower versus that of 140 kVp（t=5.208,3.583;P〈0.01）,and the image quality of 80 keV was much better.The deviation of CT values of the tissue surrounding the tube in the 80 keV image was smaller than that in the 140 kVp image（t=3.804,P〈0.01）.In the 80 keV images,the deviation of CT values of iodine tubes was smaller than that in the 140 kVp images. Conclusion Energy-spectrum imaging technique is conducive to solving beam hardening artifact due to iodated contrast agent,raising the image quality and quantitatively analyzing the tissues that surround blood vessels.
出处
《青岛大学医学院学报》
CAS
2012年第2期118-120,共3页
Acta Academiae Medicinae Qingdao Universitatis
