多層螺旋CT對慢性阻塞性肺疾病肺容積的應(yīng)用研究

1、多層螺旋CT對慢性阻塞性肺疾病肺容積的應(yīng)用研究        【中文摘要】目的:采用多層螺旋CT對COPD病人和正常查體志愿者肺容積改變進(jìn)行功能-影像對照研究,應(yīng)用低劑量MSCT對51例受試者進(jìn)行容積掃描,探討MSCT評估全肺及單肺容積的可行性;探討中、重度COPD組和正常組肺葉容積的變化及與CT肺密度參數(shù)的相關(guān)性,及雙肺各葉在不同呼吸時相肺容積的改變及其臨床意義。方法:20例正常查體者和31例COPD病人行MSCT低劑量深吸氣和深呼氣雙相全肺容積掃描及臨床肺功能檢查。掃描參數(shù):120 kV,50mA,螺距1.37

2、51,層厚10mm,間隔10mm。標(biāo)準(zhǔn)算法重建,重建層厚1.25mm,間隔0.6mm。使用ADW4.2工作站軟件進(jìn)行三維后處理及肺容積自動丈量,采用域值限定技術(shù)遮蔽表面顯示三維肺模型(SSD 3D-lung)建模,閾值上限設(shè)為-300HU,下限設(shè)為-1024HU。對MSCT肺容積指標(biāo)與臨床肺功能容積指標(biāo)間進(jìn)行相關(guān)分析。分別采用SSD 3D-lung法和閾值限定技術(shù)下手工半自動法測定深吸氣末和深呼氣末左、右肺容積。采用兩配對樣本資料t檢驗對兩種方法測定的左、右肺容積指標(biāo)進(jìn)行檢驗。應(yīng)用閾值限定技術(shù)下手工半自動法測定全部受試者深吸氣相和深呼氣相左、右肺及各肺葉容積,計算左、右肺及各肺葉在不同呼吸時相

3、所占比例。對中、重度COPD組和正常組肺葉容積的變化進(jìn)行單因素方差分析,方差齊且組間差別有統(tǒng)計學(xué)意義者采用SNK-q檢驗進(jìn)行方差分析及兩兩比較。對COPD組呼吸兩相容積差分別與均勻肺密度變化和像素指數(shù)進(jìn)行相關(guān)性檢驗,對中、重度COPD組和正常組各肺葉-910HU呼氣相像素指數(shù)進(jìn)行符號秩和檢驗。結(jié)果:1、采用閾值限定技術(shù)遮蔽表面顯示三維肺模型自動丈量的深吸氣末和深呼氣末左、右肺容積和閾值限定技術(shù)下手工半自動法測得的左、右肺容積之間無統(tǒng)計學(xué)差異。2、正常組左肺、右肺及右肺中葉深吸氣相和深呼氣相所占全肺的比例無統(tǒng)計學(xué)差異,中度組具有和正常組相似的規(guī)律,而重度組呼吸兩相各葉比例的變化較大。3、中、重度

4、COPD組全肺容積的變化較正常組減小,尤以重度為著。除右肺中葉外,中、重度COPD組和正常組左、右肺,左肺上、下葉,右肺上、下葉深吸氣相和深呼氣相肺容積的變化均存在統(tǒng)計學(xué)差異。4、均勻肺密度的變化與肺容積的變化明顯相關(guān)。5、各肺葉容積變化與各肺葉PI具有相關(guān)性,中、重度COPD組和正常組PI除右肺中葉外,其余各葉均存在統(tǒng)計學(xué)差異。結(jié)論:1、閾值限定技術(shù)下手工半自動法測定肺容積具有可行性。2、中度組左、右肺及各肺葉在不同呼吸時相的比例變化具有正常組相似的規(guī)律,而重度組各葉比例的變化較大。3、均勻密度的變化能夠反映肺容積的改變,為通氣功能提供定量指標(biāo)。4、COPD組和正常組肺葉容積的變化存在差異,

5、肺氣腫程度不同引起各肺葉容積變化不同。');【Abstract】 Objective:To study the volume changes of groups of COPD and volunteers, pulmonary function-imaging control study was done using MSCT.To study the possibility of using MSCT to evaluate volumes of whole lung and single lobes,51 subjects were done low dose volume sc

6、anning.To study the changes of different lobes in different stages and its possible clinical value,the volume changes of lobes in different stages and the corelationships between volume changes and CT attenuation parameters were compared.Mathod:20 volunteers and 31 COPD patients were done the dual p

7、hase volume MSCT and pulmonary function test.The scanning parameters were:120kV,50mA, pitch 1.375:1,layer thickness 10mm,septa 10mm.The reconstitution was standard algorithm,reconstituted thickness 1.25mm,septa 0.6mm.The post processing was used threshold limitation combine three dimensional lung mo

8、del and threshold limitation combine semi-automatic method to measure lung volumes.The lower threshold was -1024HU,the upper limit was -300HU.The volumes of left or right lung in full inspiration and full expiration using the two methods separately were compared using two paried sample document t te

9、st.The threshold limitation combine semi-automatic method was used to mearsure the left and right lung and all lobes in different stages,then computed the percentage of left and right lung and different lobes,Analysis of variance was used to compare volume changes of different lobes of moderate and

10、heavy groups of COPD patients and voluteers.Analysis of variance was used to compare the PIs(volumes below -910HU in expiration)of different lobes between groups of COPD and volunteers.Pearson correlation analysis was used to compare the changes of MLD and PIs with volume changes.Result:1.There were

11、 no differences between the volumes of left or right lung in full inspiration and full expiration using the two methods separately.2.There were no differences between the percentage of left or right lung and right middle lobe in different stages,the moderate group had the similar tendency with volun

12、teers,but the heavy group had no regularities.3.The volume changes of moderate and heavy groups of COPD were smaller than volunteers,especially heavy group.Besides right middle lobe,there were differences between other lobes by comparing the volume changes of different lobes among different groups o

13、f COPD and volunteers.4.The changes of MLD could reflect volume changes.5.Besides right middle lobe,there had differences among other lobes by comparing PIs of different lobes between groups of COPD and volunteers,and there also had correlations between volume changes and PIs.Conclusion:1.There was

14、no difference in volume measurements between using threshold limitation combine 3D-lung model and semi-automatic methold demonstrated the possibility of lung volume mearsurement using semi-automatic method.2.The percentages of left or right lung and different lobes in different stages were recommended,and there were no differences between the percentage of left or right lung and right middle lobe in different stages,the moderate group had the similar tendency with normal group,but the heavy group had no regularities.3.The changes of MLD correlated with volume