Lluch Sara, Julio Gemma, Pujol Pere, Merindano Dolores
Graefes Arch Clin Exp Ophthalmol. 2016 Jan;254(1):143-8. doi: 10.1007/s00417-015-3186-9.
Optical coherence tomography (OCT) has become a very useful tool to study in vivo different ocular structures and to improve differential diagnosis and management of many ocular pathologies. This study aims to identify pterygium alterations that trigger characteristic OCT images, and analyze if this pattern correctly demarcates lesion boundary.
Thirty-two patients, 22 men, and ten women, aged between 26 and 56 (mean age 40.5 ± 6.9) with symptomatic primary pterygium were recruited. After excision, lesion images were obtained by high-definition OCT. Specimens were stained with hematoxylin–eosin (H&E), antivimentin for all mesenchymal origin cells and altered limbal basal cells, CD45 for lymphocyte and macrophage cells, CD1a for Langerhans cells, and S100 for melanocyte and Langerhans cells.
The typical OCT wedge-shape hyperreflective mass was evident only by vimentin antibody and included, mainly, fibroblasts but also immune cells (verified by CD45) in a rich network of collagen fibers. The mass apex, often extended centripetally as a thin subepithelial line, hyperreflective by OCT, was formed by a row of fibroblasts under an apparently intact Bowman’s layer, as vimentin samples revealed. Hyperreflective epithelium overlying the mass showed a great number of vimentin-positive infiltrated cells such as melanocytes, Langerhans cells, and lymphocytes (identified by the other biomarkers). H&E staining revealed the presence of goblet cells. Nevertheless, only vimentin staining revealed the presence of altered basal cells above partially dissolved or apparently intact Bowman’s layer, coinciding in this last case with the fibroblast subepithelial line. In most of the cases (72 %), the altered cells occupied a basal segment shorter than the fibroblast subepithelial line but in some specimens, these cells exceeded the fibroblast line length.
This study demonstrated the great visual accordance between pterygium OCT images and vimentin staining. Alteration in collagen arrangement, infiltration of inflammatory cells, and fibroblast subepithelial line in the lesion apex were the main histological changes responsible for the anomalous hyperreflectivity of the OCT pattern. By contrast, altered basal cells located in the basal epithelial layer of the pterygium head could not be detected by OCT, which might generate lesion size underestimation.
光学相干断层扫描（OCT）已成为研究活体不同眼部结构以及改善多种眼部疾病的鉴别诊断和治疗的非常有用的工具。本研究旨在识别引发特征性OCT图像的翼状胬肉改变，并分析这种模式是否能正确界定病变边界。
招募了32例有症状的原发性翼状胬肉患者，其中男性22例，女性10例，年龄在26至56岁之间（平均年龄40.5±6.9岁）。切除后，通过高清OCT获取病变图像。标本用苏木精 - 伊红（H&E）染色，用抗波形蛋白抗体检测所有间充质来源细胞和改变的角膜缘基底细胞，用CD45检测淋巴细胞和巨噬细胞，用CD1a检测朗格汉斯细胞，用S100检测黑素细胞和朗格汉斯细胞。
典型的OCT楔形高反射性肿块仅在波形蛋白抗体染色下明显，主要包括成纤维细胞，但在丰富的胶原纤维网络中也有免疫细胞（经CD45证实）。肿块顶端通常向心性延伸为一条薄的上皮下线，OCT显示为高反射性，如波形蛋白样本所示，由一排位于明显完整的Bowman层下方的成纤维细胞形成。肿块上方的高反射上皮显示大量波形蛋白阳性浸润细胞，如黑素细胞、朗格汉斯细胞和淋巴细胞（由其他生物标志物鉴定）。H&E染色显示有杯状细胞存在。然而，只有波形蛋白染色显示在部分溶解或明显完整的Bowman层上方存在改变的基底细胞，在后一种情况下与成纤维细胞上皮下线一致。在大多数病例（72%）中，改变的细胞占据的基底节段比成纤维细胞上皮下线短，但在一些标本中，这些细胞超过了成纤维细胞线的长度。
本研究证明了翼状胬肉OCT图像与波形蛋白染色之间具有高度的视觉一致性。病变中胶原排列改变、炎性细胞浸润和成纤维细胞上皮下线是导致OCT模式异常高反射性的主要组织学变化。相比之下，OCT无法检测到位于翼状胬肉头部基底上皮层的改变的基底细胞，这可能导致病变大小低估。
