多层螺旋CT灌注成像对慢性阻塞性肺疾病的诊断价值

Multi-slice spiral CT perfusion imaging of chronic obstructive pulmonary disease

目的研究CT灌注成像对慢性阻塞性肺疾病（COPD）的诊断价值。方法20例COPD患者和20例志愿者行8层螺旋CT灌注成像，采用电影扫描（cine）方式，层厚5mm，扫描时间0．5s／层，注射对比剂后延时5s，总扫描时间为45s，测量感兴趣区血流量、血容量、平均通过时间及表面通透性和时间-密度曲线。结果COPD患者的时间-密度曲线较志愿者曲线平坦，峰值明显降低。COPD患者血流量[（24．77±11．49）ml·min^-1·100g^-1]、血容量[（2．48±1．02）ml／100g]及表面通透性[（2．75±1．13）ml·min^-1·100g^-1]明显低于志愿者[血流量（290．14±107．59）ml·min^-1·100g^-1、血容量（16．51±5．98）ml／100g、表面通透性（8．80±3．03）ml·min^-1·100g^-1]；平均通过时间[（10．58±4．85）s]高于志愿者[（4．50±1．71）s]，差异均具有统计学意义（P〈0．01）。结论多层螺旋CT肺灌注扫描对COPD的诊断有一定的辅助作用。

Objective To evaluate the diagnostic value of multi-slice spiral CT （MSCT） perfusion imaging in chronic obstructive pulmonary disease （COPD）. Methods Twenty COPD patients and 20 volunteers underwent 8-row detector spiral CT （MSCT） perfusion imaging using eine scan mode with 5 mm slice thickness, 0. 5 s rotation time and a total scan time of 45 s with 5 s intervals. 60 ml contrast agent （300 mg I/ml） were administered at a rate of 4 ml/s from the forearm superficial vein. The imaging data were transferred to a workstation. A time-density curve and pseudo-color map were generated automatically with GE CT perfusion 3 software, the blood flow （BF）, blood volume （BV）, mean transit time （MTT） and permeability surface （PS） were measured. Results Time-density curve was flatter and the peak of the curve was obviously lower in COPD patients than the volunteers. The BF, BV, PS in COPD patients was （24.77 ±11.49） ml ·min^-1· 100 g^-1, （2.48 ±1.02 ） ml/100 g and （2.75 ±1.13） ml ·min^-1· 100 g^-1 respectively. In volunteers was （290. 14 ±107. 59）ml ·min^-1· 100 g^-1, （ 16. 51 ± 5.98） ml/100 g, （8.80 ±3.03） ml ·min^-1· 100 g^-1 respectively. The MTr in COPD patients and volunteers was （10. 58 ±4. 85） s and （4. 50 ± 1.71）s respectively. The BF, BV and PS in COPD patients was lower than the volunteers, the MTr was higher （ P 〈 0. 01 ）. Conclusion MSCT perfusion imaging is helpful for the diagnosis of COPD.