Rivas L, Toledano A, Alvarez M I, Sanz A I, Oroza M A, Murube J
Department of Ophthalmology, Ramón y Cajal Hospital, Madrid, Spain.
Eur J Ophthalmol. 1998 Jul-Sep;8(3):131-6. doi: 10.1177/112067219800800302.
The aim of this work was to evaluate ultrastructural alterations of the conjunctiva during the clinical course of keratoconjunctivitis sicca (KCS), and to detect its earliest and most characteristic morphological changes.
The conjunctiva was studied in biopsies from 75 patients and 10 controls. Patients were classified according to the results of the Schirmer I test, break-up time, rose Bengal staining, osmolarity and impression cytology.
The conjunctiva in these KCS patients showed progressive hyperplasia, hypertrophy and cellular flattening, with diminution of goblet cell density and microvilli. In the severe cases, the epithelial cells lost their organelles, and fibrous material increased. From the early phases of KCS, clear nuclear alterations (indentation, binucleation) were found, but pyknotic nuclei or anucleated cells were only observed in the most severe cases. From the earliest stages to the most severe cases of KCS, decreases in cell membrane interdigitations were observed parallel to increases in the number and size of desmosomes. There were also increases in the number of inflammatory cells. Alterations in blood vessels were only observed in the most severe cases.
Morphological studies alone were able even in the earliest phases of KCS, to detect the squamous metaplasia that progresses from the surface of the epithelium to the connective tissue. This degenerative or adaptative cellular process was characterized mainly by marked proliferation of the cytoskeleton and a general loss of organelles, mitochondria being the least affected.
本研究旨在评估干燥性角结膜炎（KCS）临床病程中结膜的超微结构改变，并检测其最早及最具特征性的形态学变化。
对75例患者及10例对照者的结膜活检组织进行研究。根据Schirmer I试验、泪膜破裂时间、孟加拉玫瑰红染色、渗透压及印迹细胞学检查结果对患者进行分类。
这些KCS患者的结膜表现为进行性增生、肥大及细胞扁平，杯状细胞密度及微绒毛减少。严重病例中，上皮细胞细胞器丢失，纤维物质增加。在KCS的早期阶段即可发现明显的核改变（核凹陷、双核），但仅在最严重的病例中观察到核固缩或无核细胞。从KCS的最早阶段到最严重阶段，细胞膜指状交错减少，同时桥粒数量及大小增加。炎症细胞数量也增加。仅在最严重的病例中观察到血管改变。
仅形态学研究就能在KCS的最早阶段检测到从上皮表面向结缔组织发展的鳞状化生。这种退行性或适应性细胞过程的主要特征是细胞骨架明显增殖及细胞器普遍丢失，线粒体受影响最小。
