角膜格子、颗粒和斑状营养不良的特殊染色和超微结构研究

Observation of special stain and ultrastructure of lattice, granular and macular corneal dystrophy

目的探讨角膜格子、颗粒和斑状营养不良的组织病理学改变。方法对１２例角膜营养不良患者行穿透性角膜移植术后的标本，做特殊染色，光学显微镜观察摄像。部分标本做超薄切片，电子显微镜观察摄像。结果角膜格子状营养不良的角膜实质层内，光镜下可见梭形沉着物；电镜证实为含有细纤维的无定形物质，Ｍａｓｏｎ三色、ＰＡＳ及刚果红染色阳性。角膜颗粒状营养不良的角膜板层间，光镜下可见有颗粒或面包屑样沉着物。电镜检查为细胞外物质，Ｍａｓｏｎ三色，阿辛蓝染色阳性。角膜斑状营养不良的角膜光镜下，可见球形或斑状物沉积在实质层内；电镜观察角膜细胞质内有较多空泡，内含纤维和颗粒，实质内有无定形物质。胶性铁和阿辛蓝阳性染色。结论角膜格子状营养不良为淀粉样蛋白沉着物，角膜颗粒状营养不良为无定形沉着物，角膜斑状营养不良为粘多糖沉着物。

Objective To investigate the histopathological changes of lattice, granular and macular corneal dystrophy. Methods Corneal buttons were obtained from penetrating keratoplasty due to severe corneal dystrophy, and their sections and ultrathin sections with several special stains were observed under a light microscope (LM) and electron microscope (EM). Results In cases with lattice dystrophy, the stromal fusiform deposits seen under LM were confirmed to be amorphous materiel with filaments by EM and stained positively for Masson trichrome, PAS and Congo red. In cases with granular dystrophy, the granular or bread debris deposits found between laminae under LM were extracellular material observed by EM and they were stained positively for Masson trichrome and alcian blue. In cases with macular dystrophy, the stromal spheroid or macular deposits were seen under LM, and there were numerous vacuoles containing fibrils and granules in the cytoplasm of keratocytes and accumulative amorphous material in the stroma under EM; the deposits were positive for colloidal iron and alcian blue stain. Conclusion In corneal lattice dystrophy, there are amyloid deposits; in granular dystrophy, there are extracellular material deposits; and in macular dystrophy, there is mucopolysaccharide accumulation.