摘要
目的用放射性核素成像法评价糖尿病足下肢血流的变化。方法对56例糖尿病足患者和36例对照者进行99mTc-MDP三相骨显像,每个单足单独进行资料处理。在足背(楔骨和跖骨)、胫骨粗隆各勾画感兴趣区(ROI),计算各ROI放射性浓度(kc/pixel)及足部与胫骨的放射性浓度比值Rm/t。生成各ROI的时间—活度曲线,从曲线读取各部位的灌注时间Tp,并计算摄取速率V。计算并比较各指标的诊断灵敏度、特异性、准确率。各指标对糖尿病足诊断效能的差异采用u检验。结果Tp、V值、Rm/t比值在对照组分别为(32.9±9.8)s、(2.301±0.754)counts/s、0.85±0.29,在糖尿病组分别为(36.1±15.3)s、(1.574±0.341)counts/s、0.72±0.31,两组V值及Rm/t比值有统计学差异。V值诊断糖尿病足的灵敏度为80.2%、特异性为82.8%、准确率为81.5%,Rm/t比值则分别为65.2%、68.8%和67.3%。V值的灵敏度和特异性均优于Rm/t比值(P<0.05)。结论糖尿病足由于下肢血流障碍,放射性核素在足部摄取速率明显降低,足部摄取水平降低。摄取速率和足部相对摄取水平均可反映糖尿病足部血流改变,其中摄取速率更灵敏、准确。
Objective To evaluate the efficacy of 99m Tc-methylene diphosphonate (MDP) bone scintigraphy in diagnosis of diabetic foot. Methods 99m Tc-MDP three-phase bone imaging was performed in 56 patients with diabetic foot and 36 non-diabetic control subjects, each foot was analyzed independently. The radioactive concentration per pixel hence the foot to tibia ratio (R m/t ) was calculated and the time-radioactivity curve of each region of interest generated. From the curve the perfusion time (Tp) was read and the velocity of uptake rate (V) of the foot calculated. The indices such as R m/t , Tp and V were compared between the two groups by t test, and the diagnostic indices such as sensitivity, specificity, accuracy, positive prediction value and negative predictive value were compared using u test. Results In the control group, the Tp, V and R m/t were 32.9±9.8 s, 2.301±0.754 counts/s and 0.85±0.29, respectively, which were 36.1±15.3 s, 1.574±0.341 counts/s and 0.72±0.31 respectively in the diabetic group. Tp was not significantly different (t=1.693, P>0.05) between the two groups, as was V (t=8.396, P<0.001) and R m/t (t=2.759, P<0.01). When V was used as the index, the sensitivity, specificity, and accuracy were 80.2%, 82.8% and 81.5%, respectively, and those for R m/t were 65.2%, 68.8% and 67.3%, respectively. By comparison, the sensitivity (u=2.3274, P<0.05) and specificity (u=2.4068, P<0.05) of V were significantly higher than those of R m/t . Conclusions99mTc-MDP three-phase bone imaging can identify decreased uptake rate and R m/t in the diabetic foot, and the former index can be more sensitive and specific to define the hemodynamics in the diabetic foot. This technique may detect hemodynamic abnormity in early stage and greatly assist the diagnoses and treatment.
出处
《第一军医大学学报》
CSCD
北大核心
2004年第6期691-693,共3页
Journal of First Military Medical University
