Murube J, Rivas L
School of Medicine, Alcalá de Henares University, Madrid, Spain.
Eur J Ophthalmol. 2003 Mar;13(2):115-27. doi: 10.1177/112067210301300201.
To obtain deeper knowledge of the cellular transition in squamous metaplasia, and to look for a correlation between the clinical grade of severity of dry eye and the grade of squamous metaplasia of the corneal and conjunctival epithelium, studied by impression cytology.
A total of 143 patients with dry eye disorders of different grades of clinical severity and 33 control subjects of matched age and sex were studied. Symptoms, clinical tests (including Schirmer test, slit-lamp examination, break-up time, rose Bengal staining, vanishing lacunar sulci, and neovascularization), and tear osmolarity were used to establish the diagnosis of dry eye. The subjects were classified into six clinical grades, grade 0 indicating normal and grades 1 to 5 progressively more severe dry eye. Impression cytology specimens were taken from the central cornea and different areas of the conjunctiva of one eye from all patients. A morphologic and morphometric study of the photographs obtained by light microscopy showed cell size, nuclear size, nuclear-cytoplasmic ratio (N:C) in nonsecretory epithelial cells, and density of goblet cells.
Morphometric and morphologic studies of the ocular surface cells indicated significant differences, mainly in cell sizes, nuclear alterations, and the N:C ratio, in nonsecretory epithelial cells of the conjunctiva and cornea, and in goblet cell densities from the conjunctiva, between the clinically normal eyes and those with the five grades of clinical severity of dry eye, with different degrees of squamous metaplasia.
A morphologic and morphometric analysis of the ocular surface from patients with dry eye obtained by impression cytology led us to draft a new grading system containing one normal level and five levels of squamous metaplasia. This new grading system is based on a significant decrease in the number of goblet cells with less periodic acid-Schiff-hematoxylin-positive staining, an increase in nonsecretory cell size, more marked cell separation, a lower N:C ratio, and an increase in nuclear alterations. The clinical severity of the dry eye correlates with these alterations.
更深入了解鳞状化生中的细胞转变，并通过印迹细胞学研究寻找干眼临床严重程度分级与角膜和结膜上皮鳞状化生分级之间的相关性。
对143例不同临床严重程度的干眼患者和33例年龄及性别匹配的对照者进行研究。采用症状、临床检查（包括泪液分泌试验、裂隙灯检查、泪膜破裂时间、孟加拉玫瑰红染色、泪湖消失和新生血管形成）以及泪液渗透压来诊断干眼。将受试者分为六个临床等级，0级表示正常，1至5级表示干眼程度逐渐加重。从所有患者一只眼的中央角膜和结膜的不同区域采集印迹细胞学标本。通过光学显微镜对所获得照片进行形态学和形态计量学研究，观察非分泌上皮细胞的细胞大小、核大小、核质比（N:C）以及杯状细胞密度。
眼表细胞的形态计量学和形态学研究表明，临床正常眼与五级临床严重程度干眼患者（伴有不同程度鳞状化生）的结膜和角膜非分泌上皮细胞在细胞大小、核改变和N:C比方面存在显著差异，结膜杯状细胞密度也不同。
通过印迹细胞学对干眼患者眼表进行形态学和形态计量学分析，使我们制定了一个新的分级系统，包括一个正常级别和五个鳞状化生级别。这个新的分级系统基于杯状细胞数量显著减少、过碘酸-希夫-苏木精阳性染色减少、非分泌细胞大小增加、细胞分离更明显、N:C比降低以及核改变增加。干眼的临床严重程度与这些改变相关。
