摘要
目的:探讨CareDose 4D技术对头颅CT扫描的辐射剂量和图像质量的影响,评价其临床应用价值。方法:在我们医院进行头颅CT检查的患者100例,随机分两组,每组各50例。A组:采用常规固定管电压(130kV)和固定管电流(280mAs);B组:采用CareDose 4D技术,质量参考毫安为240 mAs。所有患者扫描结束后记录各自接受的辐射剂量:容积剂量指数(CTDIvol)和剂量长度乘积(DLP)并计算图像的信噪比(SNR)。头颅CT的图像质量由2位高年资主治医师进行盲法评定。两组扫描方式间辐射剂量及图像信噪比的差异采用t检验,图像质量的差异采用卡方检验进行统计学分析。结果:A组头颅CT扫描的平均CTDIvol为61.94 mGy,平均DLP为669 mGy·cm;B组的平均CTDIvol为43.32 mGy,平均DLP为467.88 mGy·cm。经t检验,两组间CTDIvol和DLP的差异均有统计学意义(P<0.001)。B组的图像信噪比略低于A组,在颅顶层面两者差异无统计学意义(P>0.05),而在鞍上池和颅底层面差异有统计学意义(P<0.05)。两组CT图像质量的比较,A组的平均优良率97.3%,B组为94.6%,差异无明显统计学意义(P>0.05)。结论:头颅CT扫描采用CareDose 4D技术可以明显减少对患者辐射剂量,并且图像质量可以满足临床诊断要求。
Purpose： To investigate the value of CareDose 4D technique in decreasing radiation dose of multi-slice spiral CT in adult skull scanning. Methods： One hundred patients undergone skull CT were equally divided into group A and group B randomly. Routine protocol （130kV and 280mAs） was used in group A, and CareDose 4D technique was used in group B （quality reference mAs 240）. Effective mAs value, volume CT dose index （CTDIvol） and dose length product （DLP） were recorded and signal to noise ratio （SNR） of the CT images were calculated after exam. The image quality at the top, suprasella cistern and base level of the skull was judged and classified as three levels （ excellent, good, poor） by two deputy chief physicians with double blind method. Results： The mean CTDIvol and mean DLP for group A was 61.94 mGy and 669 mGy.cm, those for group B was 43.32 mGy and 467.88 mGy＇cm, the differences of CTDIvol and DLP between these two groups were with statistical significance （P〈0.001）. The SNR of images in group B was lower than that in group A, at top level of the skull, the difference was with no statistical significance （P〉0.05）, but at the suprasella cistern and base level, the difference was with statistical significance （P〈0.05）. For the image quality evaluation, the average fine rate was 97.3% in group A, and 94.6% in group B. There was no statistical significant difference between them （P〉0.05）. Conclusion： CareDose 4D technique provides a regulated mAs real-time on line, it not only raises utilization rate of radiation and decreases radiation dose, but also promises the image quality in skull CT scanning, and has some clinical significance.
出处
《中国医学计算机成像杂志》
CSCD
北大核心
2013年第6期481-484,共4页
Chinese Computed Medical Imaging
