干眼症

干眼症,常见症状,干涩痒烧灼感异物感刺痛感阵发性视物模糊（晨起）迎风流泪双眼、慢性工作一天以后或长期看书看电脑后加重,怀疑干眼症！,干眼定义,干眼是由于泪液的量或质或流体动力学异常引起的泪膜不稳定和(或)眼表损害，从而导致眼不适症状及视功能障碍的一类疾病。我国临床出现的各种名称(如干眼症、干眼病及干眼综合征等)均统一称为干眼。,角膜 泪膜,脂质层,粘蛋白层,水液层,a superficial oily layer表面脂质层：meibomian glands 睑板腺a middle aqueous layer中间水液 层 :main and accessory lacrimal glands主副泪腺a deep mucin layer深层粘蛋白层：conjunctival goblet cells结膜杯状细胞,角膜 泪膜,In addition to lubricating the surface of the cornea and conjunctiva, tears produce a smooth optical surface, provide oxygen and other nutrients, and contain immunoglobulins, lysozyme,and lactoferrin. Aberrations in the tear film result from a variety of diseases (eg, dry eye)泪膜除了对角膜表面起润滑作用外，还使得角膜更加光滑，为角膜供氧及营养物质，还含有免疫球蛋白，溶菌酶，乳铁蛋白。各种各样的泪膜疾病，比如干眼症，会引起相差而使视觉质量下降。,The lacrimal glands are small and do not function fully until approximately 6 weeks after birth. Thisexplains why newborn infants do not produce tears when crying.大约出生后6周前泪腺小而无功能，新生儿哭而无泪！,The ducts from the orbital portion run through and join the ducts of the palpebral lobe. Therefore, removal of or damage to the palpebral portion of the gland can seriously reduce secretion from the entire gland. This is the reason that biopsy of the lacrimal gland is generally performed on the orbital lobe.泪腺的眶部导管穿过并加入到眼睑部导管开口于上睑穹隆部。眼睑部泪腺的损伤会严重降低泪液分泌，因此泪腺活检一般取自眶部泪腺。,Aqueous lacrimal secretion has traditionally been divided into basal low- level secretion and reflex secretion. Previously, it was argued that the accessory glands provided basal tear secretion and the lacrimal gland was responsible for reflex tearing. However, recent evidence suggests that all tearing may be reflex. The tear film composition is as follows: Goblet cells within the conjunctiva provide the inner layer of the tear film by secreting mucin, which allows for even distribution of the tear film over the ocular surface. The main and accessory lacrimal gland secretions form the intermediate aqueous layer of the tear film. Meibomian glands produce the oily outerlayer of the tear film, which reduces the evaporation of the underlying aqueous layer.泪液的分泌，传统分为基础的低水平分泌和反射性分泌，以往认为主泪腺负责反射性分泌（流泪），副泪腺负责基础泪液分泌（泪膜）。但是现在的观点认为，所有的泪液分泌都是神经反射性的。结膜杯状细胞分泌的粘蛋白组成了泪膜内层，负责泪膜在角膜表面均匀展开主泪腺和副泪腺共同分泌中间的水液层睑板腺分泌的脂质层位于泪膜最外层，防止其下水液层的增发,我国的发病率约在2130危险因素老龄女性高海拔糖尿病翼状胬肉空气污染眼药水滥用使用视屏终端角膜屈光手术过敏性眼病和部分全身性疾病等。,病因分类,程度分类,临床检查,裂隙灯检查,眼睑、睑缘及睑板腺泪河高度结膜和角膜改变,泪河高度,初步判断泪液分泌量荧光素染色泪液上下光带的距离正常泪河切面为凸形高度为0305 mm,泪膜破裂时间(breakup time，BUT),反映泪膜的稳定性下睑结膜滴人510ul荧光素钠或荧光素试纸条嘱患者眨眼3或4次自最后1次瞬目后自然平视睁眼至角膜出现第1个黑斑的时间计算正常BUT10 S,眼表面活体细胞染色,