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长期以来,金属植入物作为常用的植入体在骨折、骨更换、骨肿瘤切除后人工骨替换等领域发挥了巨大的作用。金属植入物植入人体后临床疗效评估常通过影像学特别是CT来实现,借助CT值来区别正常组织与病变组织,但是金属植入物产生的伪影(失真的CT值)会使图像质量下降从而影响临床疗效的评估,特别是金属植入物周围组织如骨肿瘤等常被忽视。双源CT有望能改善这一现象,双源CT有两套X线成像系统,能同时产生两种不同能量的X线,从而获得同一位置同一时刻的两组图像,对这两组图像进行能谱分析从而融合得到第3组图像[1-2]。过去利用能谱成像分析改善金属植入物影像的定性分析报道较多,但定量分析较少[3-6]。
双源CT单能谱成像技术在正确评估金属植入物周围组织CT值中的应用
The application of dual-energy CT in the CT quantitative study values of water surrounding metal implants
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摘要:
目的 探讨双源CT单能谱成像技术在正确评估金属(不锈钢)植入物周围组织CT值中的应用。 方法 对含有金属植入物的水模体使用双源CT双能量扫描,采用双能量扫描程序,一次性扫描采集2个不同能量(80 kV及140 kV)的数据,采用单能谱成像技术对所得原始数据进行处理,得到融合后图像。对金属植入物周围的水进行CT值测量和统计分析。 结果 3种图像(80 kV CT图像、140 kV CT图像、能谱融合图像)中,能谱融合图像的质量最高,140 kV CT图像次之,80 kV CT图像最差。用SAS9.1软件分别比较80 kV CT图像和140 kV CT图像与能谱融合图像沿着金属植入物右侧方向0.1、0.5、1.0、1.5、2.0、2.5、3.0 cm的CT值,结果发现它们之间的差异基本上都有统计学意义。 结论 双源CT单能谱成像技术改善了金属植入物植入后CT检查的图像质量。 -
关键词:
- 体层摄影术,X线计算机 /
- CT值 /
- 金属植入物
Abstract:Objective To evaluate monoenergetic imaging of dual energy CT in the visualization of metal implants(stainless steel implants). Methods Two different data(80 and 140 kV)of water phantom which contained metal implants were collected in one-time scanning using dual-energy scanning sequence. Monoenergetic technique which two different imaging at 80 kV and 140 kV were used for subtraction to removing metal artifacts was applied to generate the new imaging. The CT value of water surrounding metal implants were measured and compared. Results In the three images(80 kV, 140 kV, spectrum image fusion), the latter quality is the highest and the 80 kV scanning images′ quality was the worst. The difference between CT values of 80 kV images(140 kV images) and energy spectrum images along the right direction 0.1, 0.5, 1, 1.5, 2.0, 2.5, 3.0 cm of the metal basically was significant assessed by the SAS9.1 software. Conclusions Dual energy CT can effectively reduce artifacts of metal implants and will provide high image quality in the area with metal implants. -
Key words:
- Tomography, X-ray computed /
- CT values /
- metal implants
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