两种晶体厚度的单光子发射计算机断层成像部分固有性能指标的比较  

Comparison of partial intrinsic performance of SPECT with two different crystal thickness

作　　者：宋颖[1] 刘辉[1] 

机构地区：[1]中国疾病预防控制中心辐射防护与核安全医学所 辐射防护与核应急中国疾病预防控制中心重点实验室,100088

出　　处：《中华放射医学与防护杂志》2018年第1期52-55,共4页Chinese Journal of Radiological Medicine and Protection

摘　　要：目的 探索研究单光子发射计算机断层成像（SPECT）设备探头晶体厚度的改变对设备性能的影响，以期得到改变量化，深入分析原因，为改善机器性能提高图像质量提出有效措施。方法 选取3个不同厂家的12台探头晶体厚度为1英寸（1英寸=2.54 cm）的SPECT和35台探头晶体厚度为3/8英寸的SPECT，按照美国电器制造商协会（NEMA）标准测量固有非均匀性和固有空间分辨力指标。在探头晶体厚度为3/8英寸的设备中按照不同厂家分类比较，选取测量结果无差异的厂家设备作为1组数据，并与晶体厚度为1英寸的设备指标进行比较。采用两独立样本t检验，比较两种晶体厚度的探头在以上两种性能指标的差异。结果 探头晶体厚度为1英寸和3/8英寸时测得的固有非均匀性为（3.22±0.83）%和（2.51±0.65）%，两者比较差异有统计学意义（t=-3.601，P 〈 0.05）。探头晶体厚度为1英寸和3/8英寸时，测得的固有空间分辨力为（4.60±0.14）和（3.70±0.35） mm，两者比较差异有统计学意义（t=-13.03，P 〈 0.05）。结论 SPECT探头晶体厚度的改变影响设备的固有非均匀性和固有空间分辨力，应采取有效措施弥补晶体厚度改变带来的图像质量下降，以保证设备临床使用的效果。Objective To explore the influence of changing probe crystal thickness on the performance of single photon emission computed tomography （SPECT）, so as to achieve quantitative improvements and in-depth analyses of the related reasons and to provide effective measures in improving the image quality of SPECTs. Methods Both 12 SPECT units each of 1 inch（1 inch=2.54 cm） thick crystal and 35 SPECT units each of 3/8 inch thick crystal were chosen. Both intrinsic uniformity and intrinsic spatial resolution were measured according to the National Electrical Manufacturers Association （NEMA） standard. The performance was compared between SPECT units with 1 inch thick probe and 3/8 inch thick crystal. Results The intrinsic uniformity measured for 1 inch thick probe and 3/8 inch thick crystal were （3.22±0.83）% and （2.51±0.65）%. The difference between the two groups was statistically significant （t=-3.601, P 〈 0.05）. Intrinsic spatial resolutions of 1 inch thick probe and 3/8 inch thick crystal were （4.60±0.14） and （3.70±0.35） mm, with statistical significance between the two groups （t=-13.03, P〈0.05）. Conclusions The crystal thickness is a significant factor influencing SPECT＇s intrinsic uniformity and intrinsic spatial resolution. It is recommended that effective measures be taken to compensate the declined image quality due to crystal thickness change, to make sure the equipment is qualified for clinical use.

关 键 词：单光子发射计算机断层成像 晶体 固有空间分辨力 固有空间非均匀性 

分 类 号：R197.39[医药卫生—卫生事业管理]