目的

分析单光子发射型计算机断层（single photon emission computed tomography，SPECT）肺灌注显像/低剂量计算机断层扫描（computed tomography，CT）诊断慢性阻塞性肺疾病（chronic obstructive pulmonary disease，COPD）并发肺栓塞（pulmonary embolism，PE）患者的安全性和有效性。

方法

选择2014 年1 月至2024 年12 月我院收治的COPD 疑似PE 患者80 例为对象，患者接受SPECT 肺灌注显像及低剂量肺部CT 检查（同机检查），融合显像，记录显像过程中不良反应。 以最终出院结果为标准，分析对比SPECT、低剂量CT、SPECT/CT 检测结果及诊断价值；记录不同显像技术对肺部病变检出率及肺影像学特征。

结果

80 例COPD 疑似PE 患者中确诊PE 43 例，非PE 37 例。 SPECT/CT 融合、SPECT、低剂量CT 诊断结果分别为阳性40 例、30 例、35 例，阴性35 例、25 例、28 例。 SPECT/CT 融合诊断一致性（Kappa=0.843）高于SPECT、低剂量CT，SPECT/CT 的诊断灵敏度93.02%、特异性94.59%、阳性预测值95.24%、阴性预测值92.11%及准确性93.75%高于SPECT 69.77%、67.57%、71.43%、65.79%、68.75%、低剂量CT 81.40%、75.68%、79.55%、77.78%、78.75%（P＜0.05）。 确诊PE 43 例中肺段病变91 个，亚肺段病变97 个。 SPECT/CT、SPECT、低剂量CT 显像技术对PF 肺段病变检出率分别为92.31%、83.52%、85.71%，差异无统计学意义（P＞0.05），SPECT/CT 融合对亚肺段病变检出率95.88%高于SPECT 76.29%、低剂量CT 81.44%（P＜0.05）。 PE 患者SPECT 肺灌注显像可见单个或多个放射性稀疏缺损区，放射性分布均匀或不均匀。 低剂量CT 图像可见肺血管走行区域充盈缺损，肺透亮度增加，肺纹理稀疏。 SPECT/CT 融合图像中PE 患者肺段放射性稀疏缺损与肺血管走行区域充盈缺损匹配。

结论

低剂量SPECT/ CT 肺灌注融合显像诊断COPD 并发PE 具有有效性及安全性，可为临床PE 诊断提供参考具有意义。

Objective

To analyze the safety and efficacy of diagnosis of single photon emission computed tomography （SPECT） lung perfusion imaging/low-dose computed tomography （CT） in patients with chronic obstructive pulmonary disease （COPD） complicated by pulmonary embolism （PE）.

Methods

Eighty COPD patients suspected of PE admitted to our hospital from January 2014 to December 2024 were selected as subjects. The patients underwent SPECT lung perfusion imaging and low-dose lung CT examination （samemachine examination），followed by image post-processing fusion. Adverse reactions during imaging were recorded. Using the final discharge results as the gold standard，the diagnostic results and value of SPECT，lowdose CT，and SPECT/CT were analyzed and compared. The detection rates and imaging characteristics of different imaging techniques for lesion locations were recorded.

Results

Among the 80 COPD patients suspected of PE，the gold standard confirmed 43 cases of PE and 37 cases of non-PE. The diagnostic results of SPECT/CT fusion，SPECT，and low-dose CT were 40 positive cases，30 positive cases，and 35 positive cases，and 35 negative cases，25 negative cases，and 28 negative cases，respectively. The diagnostic consistency of SPECT/CT fusion （Kappa=0.843） was higher than that of SPECT and low-dose CT. The diagnostic sensitivity（93.02%），specificity （94.59%），positive predictive value （95.24%），negative predictive value （92.11%），and accuracy （93.75%） of SPECT/CT fusion were higher than those of SPECT （69.77%，67.57%，71.43%，65.79%，68.75%） and low-dose CT （81.40%，75.68%，79.55%，77.78%，78.75%） （P＜0.05）. Among the 43 PE cases diagnosed by the gold standard，there were 91 segmental lesions and 97 subsegmental lesions. The detection rates of segmental lesions by different imaging techniques （92.31% vs. 83.52% vs. 85.71%） showed no statistically significant difference （P＞0.05）. However，the detection rate of subsegmental lesions by SPECT/CT fusion （95.88%） was higher than that by SPECT （76.29%） and low-dose CT （81.44%） （P＜0.05）. In PE patients，SPECT lung perfusion imaging showed single or multiple radioactive sparse defect area，with uniform or uneven radioactive distribution. Low-dose CT images revealed filling defects in the pulmonary vascular pathways，increased lung translucency，and sparse lung texture. In SPECT/CT fusion images，the radioactive sparse defect area in the lung of PE patients matched the filling defects in the pulmonary vascular pathways.

Conclusion

Low-dose SPECT/CT lung perfusion fusion imaging is effective and safe for diagnosing COPD complicated with PE，providing accurate information for clinical PE diagnosis.