16层螺旋CT双期脑血管成像三种减影方法的对比研究

16- Slice Spiral CT Dual- Phase Cerebral Angiography:Comparison Study of Three Bone Removal Software Programs

目的比较16层螺旋CT双期脑血管成像3种不同软件减影法（Subtraction，Objecteditor及NeuroDSA）的图像质量与便捷性及临床应用差异。方法60例双期脑血管成像随机分成A组（同步扫描）与B组（非同步扫描）；分别用3种软件减影，计算后处理时间及图像质量评分（1—8分），比较3种软件减影组内及组间的差异。其中行DSA检查15例，对比3种减影显示病变的差异并采用统计学t检验。结果3种软件减影时间，手工修饰时间及图像评分两组组内比较：Object editor减影时间[A组（2．52±0．37）min，B组（2．47±0．39）min]均最短（P〈0．05）；Subtraction与NeuroDSA差异不显著。Subtraction减影手工修饰时间[A组（10．71±4．16）min，B组（14．34±3．75）miu]均最长（P〈0．05），动、静脉期图像评分（A组5．67±0．92，5．60±1．16；B组3．30±1．75，4．03±1．69）均最低（P〈0．05），Object editor与NeuroDSA差异不显著。3种减影组间比较：A组Subtraction减影动、静脉图像评分高于B组，手工修饰时间短于B组（P〈0．05），其余两组组间比较均无显著差异。对比15例DSA检查，Object editor与NeuroDSA减影均能显示诊断所有病变，准确性为100％。Subtraction减影漏诊8处病变，准确性为53％。结论同步扫描是Subtraction减影成功的关键，对Object editor，NeuroDSA减影无显著意义，后2种减影诊断血管病变能力相当，但NeuroDSA减影操作更自动化，推荐为16层螺旋CT脑血管减影首选。

Objective To compare the effects of three different bone removal software programs （Subtraction, Object editor and Neuro DSA） on the image quality, the convenience and the clinic usefulness in dual -phase cerebral angiogra- phy with a Siemens 16 - slice spiral CT unit. Methods A total of 60 patients were randomly and equally divided into group A （ n = 30） and group B （ n = 30）. Dual - phase cerebral angiography with synchronous technique was carried out in the patients of group A, while dual - phase cerebral angiography with non - synchronous technique was employed in the pa- tients of group B. The post - processing time for the removal of bone structures by using three different bone removal tech- niques （Subtraction, Object editor and Neuro DSA） was calculated separately, and the image qualities produced by the three techniques were evaluated with score （ 1 - 8 score）. The differences in the post - processing time and in the image quality between the two groups as well as between the techniques in the same group were analyzed. Additional DSA was performed in 15 cases. The results were statistically analyzed with t -test. Results By using Object editor software the post - processing time of the group A and the group B was （2.52±0.37） min and （2.47 ± 0.39） min respectively, which was the lowest value of post - processing time in each group （ P 〈 0.05 ）. The differences in post - processing time between Subtraction and Neuro DSA were not significant. The manual time of Subtraction software in the group A and the group B was （ 10.71 ± 4.16） min and （ 14.34 ±3.75 ） min respectively, which was the longest value of post - processing time in each group （ P 〈 0.05 ）. The image evaluation scores of the arterial phase and venous phase was 5.67 ± 0.92 and 5.60 ± 1.16 respectively in the group A and 3.30 ± 1.75 and 4.03 ±1.69 respectively in the group B, which were the smallest （ P 〈 0. 05 ）. The difference in image scores between Object editor and Neuro DSA was not significant. The image evaluationscores of the arterial phase and venous phase using Subtraction software in the group A were higher than those in the group B, while the manual time of Subtraction software in the group A was shorter than that in the group B （ P 〈 0. 05 ）. For the other software techniques, no significant differences existed between the two groups. Compared with DSA of 15 cases, both Object editor and Neuro DSA could demonstrate all abnormalities with an accuracy of 100%. Subtraction technique missed diagnosis of eight lesions, with a diagnostic accuracy of 53%. Conclusion Synchronous CT dual - phase scanning is the key to ensure a successful Subtraction technique, although it has no obvious value for Object editor and Neuro DSA software programs. Object editor software and Neuro DSA software have the same ability in discovering vascular lesions. Nevertheless, the manipulation of Neuro DSA software is more automatic. Therefore, it should be recommended as the bone removal software of first choice in dual - phase cerebral angiograohy with 16 - slice spiral CT unit.