不同期别煤工尘肺小叶间隔线的高分辨率CT表现与病理对照研究

Morphologic manifestation of interlobular septa and pathologic basis in different stage coal worker's pneumoconiosis on high-resolution CT

目的研究煤工尘肺小叶间隔线在高分辨率CT(HRCT)上的基本形态和病理基础。方法28例有煤尘接触史的尸解全肺标本,固定、干燥,进行冠状面HRCT扫描。选取HRCT上线样影丰富的肺标本薄片进行冠状面大切片(50-150μm)和组织学切片(5-8μm)制作。分析比较小叶间隔线在HRCT上的形态。结果28例肺标本中HRCT扫描发现23例有不同类型的小叶间隔线。以规则型小叶间隔线为主10例,无尘肺9例、Ⅰ期1例;以不规则型小叶间隔线为主10例,无尘肺2例、Ⅰ期2例、Ⅱ期6例;破坏型小叶间隔3例,Ⅱ期2例、Ⅲ期1例。规则型与不规则型(q= 4．3831,P=0．0024)、规则型与破坏型小叶间隔线(g=5．4715,P=0．0006)在不同期别煤工尘肺中的差异有统计学意义。组织病理学上规则型小叶间隔线主要表现为小叶间隔水肿(10／10)、小叶间隔内炎性渗出(8／10)和局限于小叶间隔内的纤维化(9／10);不规则型小叶间隔线主要表现为小叶间隔内及邻近小叶实质煤尘沉积(13／16)和纤维化突破小叶间隔(15／16);差异有统计学意义(Fisher精确概率法,P值均<0．05)。破坏型小叶间隔线是由于纤维融合块、肺气肿等造成小叶间隔线移位和破坏。结论规则型、不规则型和破坏型小叶间隔线并存于各期煤工尘肺和煤尘接触者中,其代表的是不同程度的纤维化和不同量的煤尘沉积。

Objective To investigate HRCT appearances of interlobular septa and pathologic basis in coal worker＇s pneumoconiosis （CWP）. Methods Twenty-eight lung specimens were available from autopsy examination of the patients with coal worker＇s pneumoconiosis and occupational exposure to coal dusts. All lung specimens were inflated and fixed by Heitzman＇s method. HRCT scans, gross specimen section（50 - 150 μm thickness） and histologic section （5 - 8 μm thickness） were performed on dry lung specimens and HRCT-pathologic correlation of thickened interlobular septa were analyzed. Results Thickened interlobular septa were seen in 23 of 28 lung specimens. The morphologic manifestation of thickened interlobular septa on HRCT could be classified into three types：regular type, irregular type and distorted type of thickened interlobular septa. （ 1 ） Predominant regular type of thickened interlobular septa were seen in 10 of 28 lung specimens, including no CWP9 cases and stage Ⅰ CWP 1 case. （2） Predominant irregular type of thickened interlobular septa were seen in 10 of 28 lung specimens, including no CWP 2 cases, stage 1 2 cases, and stage Ⅱ 6 cases. （3） Distorted type of thickened interlobular septa were seen in 3 of 28 lung specimens, including stage Ⅱ 2 cases and stage Ⅲ 1 case. In different stage coal worker＇ s pneumoconiosis, morphologic manifestation of interlobular septa had significant different between regular and irregular type （ q = 4. 3831, P = 0. 0024）, regular and distorted type （ q = 5.4715, P = 0. 0006 ） of thickened interlobular septa. On the basis of gross pathology and histologic section, regular type of thickened interlobular septa was composed of edema（ 10/10）, inflammation （ 8/10 ）, slight fibrosis （9/10）. Irregular type of thickened interlobular septa was composed of serious clusters of coal dusts （ 13/16 ） and fibrosis （15/16）. By way of statistical analysis, there was significant different pathologically between regular and irregular type of thickened interlobular septa （ Fisher＇ s exact test, P 〈 0. 05 ）. Distorted type of thickened interlobular septa correlated pathologically with conglomerate fibrosis masses and emphysema. Conclusion Regular, irregular and distorted type of thickened interlobular septa can coexist in different stage CWP and occupational exposure to coal dusts, and clue to different extent, degree fibrosis and deposits of coal dusts.