自制足部简易固定装置在足SPECT/CT断层骨显像定位诊断中的应用

目的 探讨自制足部简易固定装置在足单光子发射计算机断层显像/计算机断层扫描（SPECT/CT）断层骨显像辅助定位诊断中的应用价值。方法 前瞻性对照研究。纳入南京医科大学附属无锡第二医院2019年11月—2020年11月30例行⁹⁹Tc^m-亚甲基二膦酸盐SPECT/CT足部断层骨显像发现足部骨代谢异常患者的临床及影像学资料,其中男13例、女17例,年龄42~83（65.9±9.8）岁。采用抽签法分组：观察组15例,使用足部固定装置;对照组15例,不使用足部固定装置,采用常规体位摆放肢体。比较两组患者的年龄、性别、体质量指数（BMI）、病变侧别等基线资料。测量并比较两组患者足长轴与扫描床的夹角、足部扫描长度、扫描时间、辐射剂量,以及图像融合时X、Y、Z轴三个方向的偏差量。结果 两组患者的年龄、性别、BMI、病变侧别比较,差异均无统计学意义（P值均>0.05）。观察组的足长轴与扫描床的夹角（95.6°±4.1°）小于对照组（123.8°±6.5°）,差异有统计学意义（t=-14.17,P<0.001）;观察组足部扫描长度较对照组减少27.6%、扫描时间缩短27.8%、CT辐射剂量减少24.1%,分别为（15.2±1.4）和（21.0±1.8）cm、（6.89±0.63）和（9.54±0.79）s、（28.6±2.0）和（37.7±2.9）mGy·cm,差异均有统计学意义（t=-10.02、-10.08、-10.16,P值均<0.001）;两组间图像融合的偏差量差异均无统计学意义（t=1.13、-0.57、-0.13,P值均>0.05）。结论 该足部简易固定装置能够在不影响图像融合质量的情况下得到足的标准解剖位图像,并能降低患者所受CT辐射剂量。

Application of self-made simple foot fixation device in localization diagnosis on SPECT / CT tomographic bone scintigraphy of foot

Objective To investigate the application value of self-made simple foot fixation device in the auxiliary localization diagnosis using single photon emission computed tomography/computed tomography(SPECT/CT) tomographic bone scintigraphy of the foot. Methods Thirty patients(13 males and 17 females, aged 42-8365.9±9.8]years) who underwent ⁹⁹Tc^m methylene diphosphonate SPECT/CT bone scintigraphy and presented with abnormal foot bone metabolism in our hospital from November 2019 to November 2020 were prospectively selected. On the tomographic bone scintigraphy of the foot, 15 patients were selected by drawing lots with a foot fixation device, whereas 15 patients were selected without the device, and the limbs were placed in the conventional position. The two groups were compared in terms of baseline data, namely, age, sex, body mass index(BMI), and pathological side. The angle between foot long axis and scan bed, scanning length, scanning time, radiation dose, and degrees of deviation of the X-, Y-, and Z-axes of the two modes were measured and compared. Results No significant differences in age, sex, BMI, and pathological side were observed between the two groups (all P values >0.05). The angle between the foot long axis and the scan bed in the observation group (95.6°±4.1°) was smaller than that of the control group (123.8°±6.5°). The difference was statistically significant (t=-14.17, P<0.001). The foot scanning length, scanning time, radiation dose of CT in the observation group were reduced by 27.6%, 27.8%, and 24.1%, respectively, relative to those in the control group (15.2±1.4] cm and 21.0±1.8] cm; 6.89±0.63] s and 9.54±0.79] s; 28.6±2.0] mGy·cm and 37.7±2.9] mGy·cm; t=-10.02, -10.08, -10.16; all P values <0.001). No significant difference in image fusion deviation was found between the two groups (t=1.13, -0.57, -0.13; all P values >0.05). Conclusions The simple foot fixation device designed in this study can obtain the standard anatomical images of the foot without affecting image fusion quality, which can reduce CT radiation dose.