摘要
目的 探讨使用不同管电流时间积行婴幼儿头颅CT扫描时,影响图像质量的客观因素.方法 随机将90例行头颅CT扫描的婴幼儿分成3组,测量每个婴幼儿的头颅最大前后径（MAPD）,选择性研究3个参考层面（幕下小脑、幕上基底节和半卵圆中心层面）,每个组只研究一个层面,每个层面用150、100及80 mAs管电流时间积进行扫描,对各层面图像进行主观质量评分,并测量其客观量化噪声值.结果 90例婴幼儿平均MAPD为（148.0±17.4）mm.在小脑层面,主观图像质量得分较其他2个层面低.管电流时间积为150、100和80 mAs时,小脑层面的量化噪声值分别较幕上层面高6.3%、9.4%和22.9%.MAPD与图像主观质量评分及客观量化噪声值之间均呈显著性相关.结论 在婴幼儿头颅CT扫描时,小脑层面固有高噪声及MAPD是影响婴幼儿头颅低剂量CT扫描图像质量的客观因素.
Objective To investigate the objective factors that affect the image quality of infant cranial CT using different mAs. Materials and Methods Ninety infants were divided into three groups randomly. The maximum anteroposterior diameter （MAPD） of skull of each infant was measured. Three reference levels, cerebellar, basal ganglia and centrum semiovale levels were selected respectively. Only one level was studied in each group and scanned with 150, 100 and 80 mAs. The subjective quality grade and the objective noise of all images were recorded and analysed statistically. Result The average MAPD of ninety patients was （148.0 ± 17.4）mm. On the cerebellar level, the subjective quality grade was lower than the other two levels, which were 6.3% , 9.4% and 22.9% respectively when mAs were 150, 100 and 80 mAs. Both quality grade of image and objective noise were significantly correlated with MAPD.Conclusion The inherent high noise of cerebellar level and MAPD were the objective factors that affect the image quality of low-dose cranial CT of infant.
出处
《中华放射医学与防护杂志》
CAS
CSCD
北大核心
2010年第4期472-474,共3页
Chinese Journal of Radiological Medicine and Protection
基金
深圳市科技局科技计划基金资助项目（200304193）
