多层螺旋CT肺容积与肺密度指标与肺通气功能的相关性

Pulmonary density and pulmonary volume indices measured with MSCT:correlative study with pulmonary ventilation function test

目的通过分析16层螺旋CT(MSCT)肺容积和肺密度指标与肺功能试验(PFT)肺通气功能指标的相关性,观察MSCT检查评价肺功能的可行性。方法对60例受检者行胸部MSCT及PFT检查。MSCT观察不同呼吸时相下肺容积和肺密度指标:深吸气末全肺容积(Vin)、深呼气末全肺容积(Vex)、肺容积差(Vin-Vex)、肺容积比(Vex/Vin)、深吸气末平均肺密度(MLDin)、深呼气末平均肺密度(MLDex)和肺密度差(MLDex-MLDin)。PFT观察肺功能指标包括肺总量(TLC)、残气量(RV)、残气量与肺总量比(RV/TLC)、用力肺活量(FVC)、第1秒用力呼气容积(FEV1)和第1秒用力呼气容积与用力肺活量比(FEV1/FVC)。结果60例中,MSCT诊断正常肺部34例,肺气肿26例;PFT诊断正常肺部37例,肺气肿23例。MSCT肺容积指标与肺功能指标均呈不同程度的正相关,绝对指标Vin、Vex与PFT静态肺容积指标TLC、RV的相关性高于肺通气功能指标FVC、FEV1。MSCT肺密度指标与PFT静态肺容积指标呈负相关,与肺通气功能指标呈正相关。结论MSCT肺容积和肺密度检测均能较好地判断患者肺功能状况,深呼气末CT扫描图像对肺气肿的诊断价值优于深吸气末。

Objective To study the correlation of pulmonary volume and pulmonary density indices measured with 16-slice CT （MSCT） and pulmonary function test （PFT） outcomes. Methods Chest MSCT scan and PFT were performed in 60 cases. The pulmonary density and pulmonary volume indices included end deep inspiratory volume （Vin）, end deep expiratory volume （Vex）, difference in lung volume （Vin- Vex ）, ratio in lung volume （Vex/Vin）, mean lung density at end deep inspiratory phase （MLDi.）, MLD at end deep expiratory phase （MLDex） and difference in lung density （MLDex- MLDin ）, while the indices of PFT were total lung capacity （TLC）, residual volume （RV）, RV/TLC, forced vital capacity （FVC）, forced expiratory volume in one second （FEV1） and FEV1/FVC. Results Thirty-four cases were normal, and 26 cases were diagnosed emphysema with MSCT, whereas, 37 cases were normal, and 23 cases were diagnosed emphysema with PFT. MSCT volumetric indices correlated positively with PFT indices at different level. The correlations between Vin, Vex and the PFT volume indices were higher than those of ventilation indices such as TLC and RV. MSCT pulmonary density indices correlated negatively with PFT volumetric indices and positively with ventilation indices. Conclusion MSCT pulmonary volume and density indices can detect pulmonary function rather accurately. MSCT images obtained at end deep expiratory phase are superior to those at end deep inspiratory phase for the diagnosis of pulmonary emphysema.