2022年医学专题—白内障幻灯片.ppt

打一疾病(jbng),不红不痛渐昏朦，薄雾轻烟渐渐浓。初时一眼先昏暗，数日逐渐障双瞳(shun tn)。千金难买药见效，金针一拨当日空。,第一页，共一百零九页。,cataract,胜利(shngl)医院林雪媛,第二页，共一百零九页。,教学(jio xu)目的,了解白内障的发生原因及其分型。掌握老年性白内障各型的特点。掌握白内障的手术适应症及白内障术后矫正视力的方法(fngf)。了解先天性白内障和代谢性白内障的分型及特点。了解晶状体脱位的分型及临床表现。,第三页，共一百零九页。,What is cataract?,A cataract is an opacity(or cloudy changes)of the lens that can cause vision problems.任何先天性或后天性因素引起的晶状体混浊使其透明性下降(xijing)，称为白内障。,第四页，共一百零九页。,第五页，共一百零九页。,LENS,The lens is surrounded by a thick lens capsule which is the basement membranae of the lens epithelial cells.晶状体囊是一层包绕整个晶状体的透明囊状基底膜。Epithelial cells at the lens equator continue to be produced throughout life,so that older lens fibers are compressed into a central nucleus;younger fibers around the nucleus make up the cortex.位于晶状体赤道部囊下的上皮细胞终生增殖，不断形成晶状体纤维(xinwi)，将旧的纤维(xinwi)挤向中心的核，核外较新较疏松的纤维(xinwi)构成皮质。,第六页，共一百零九页。,第七页，共一百零九页。,第八页，共一百零九页。,causes,Aging most commonLong-term ultraviolet(UV)light,especially from sunlight Diabetes or other systemic diseasePast eye infections,injuries or surgery Smoking Long-term use of certain medications(such as steroids)heredity,第九页，共一百零九页。,Pathogenesis,The lens is made mostly of water and protein.The protein is arranged to let light pass through and focus on the retina.Sometimes some of the protein clumps together.This can start to cloud small areas of the lens,blocking some light from reaching the retina and interfering with vision.晶状体主要由水和蛋白组成。发生白内障的晶状体特征性改变是蛋白之间的交联形成聚合物，使光线(gungxin)散射增强，晶状体透明度下降。,第十页，共一百零九页。,自由基引起的氧化(ynghu)损伤 晶状体上皮细胞氧化损伤膜蛋白降解细胞膜通透性增加晶状体内渗透压增高、肿胀；晶体蛋白之间二硫键形成增多蛋白交联形成高分子量聚合物光散射增强，晶状体混浊。细胞凋亡及其调控,第十一页，共一百零九页。,normal Vs.cloudy lens,第十二页，共一百零九页。,Clinical Findings,Symptoms Blurring or dimness of vision 视力下降(xijing)colors appear faded 色觉改变 Sensitivity to light and glare 眩光 Double or multiple vision 复视或多视 Change in refraction 屈光改变,第十三页，共一百零九页。,第十四页，共一百零九页。,Eye Exam,Vision acuity test Slit lamp Ophthalmoscope In most cases,eye drops are used to dilate(widen)pupils before the exam.Tonometry,第十五页，共一百零九页。,Slit lamp,第十六页，共一百零九页。,第十七页，共一百零九页。,classification,判断晶状体混浊范围和程度 将瞳孔充分散大，采用裂隙灯和后照法，区别晶状体混浊的类型核性（N）、皮质性（C）、后囊下（P）、核的颜色（NC）晶状体核硬度分级标准（据 NC）度：透明，无核，软性(run xn)；度：核呈黄白色或黄色，软核；度：核呈深黄色，中等硬度核；度：核呈棕色或琥珀色，硬核；度：核呈棕褐色或黑色，极硬核。,第十八页，共一百零九页。,Age-related cataract,年龄相关性白内障是最为常见(chn jin)的白内障类型，多见于50岁以上的中、老年人，随年龄增加其发病率升高。,第十九页，共一百零九页。,There are three major types of cataract that are named depending on the location within the lens that is most affected.These are cortical,nuclear and posterior subcapsular.A given lens may have components of all three types of cataract.根据晶状体开始出现混浊(hnzhu)的部位，老年性白内障分为3种类型：皮质性、核性及后囊下白内障。一个晶状体可能同时发生这3型白内障。,第二十页，共一百零九页。,第二十一页，共一百零九页。,第二十二页，共一百零九页。,Cortical cataract,the most common type of age-related cataract.four stages as follows:,第二十三页，共一百零九页。,Incipient stage 初发期,Cortical changes may begin as small peripheral water clefts.皮质中空泡和水隙形成。Radical pattern opacity.放射状混浊。检眼镜检查可见(kjin)红光反射中放射状或片状阴影。早期较周边的混浊并不影响视力，病程发展慢。,第二十四页，共一百零九页。,初发期,第二十五页，共一百零九页。,Intumescent stage 肿胀(zhngzhng)期,The lens takes up water,it becomes intumescent.混浊加重，皮质吸水肿胀，晶状体体积增大。Anterior chamber gets shallow.前房变浅，有闭角型青光眼体质者可诱发青光眼急性发作。斜照法检查虹膜投影(tuyng)现象。视力明显下降，眼底难以窥清。,第二十六页，共一百零九页。,肿胀(zhngzhng)期,第二十七页，共一百零九页。,Mature stage 成熟期,Liquid escapes and the lens shrinks.晶体内水分溢出，肿胀消退，体积变小。The lens protein is totally opaque.晶体完全(wnqun)混浊，呈乳白色。视力降至手动或光感，眼底不能窥入。,第二十八页，共一百零九页。,成熟期,第二十九页，共一百零九页。,Hypermature Stage 过熟期,A long-standing or very mature cataract may undergo liquefaction of the lens cortex.This liquid may escape through the intact capsule,leaving a shrunken lens with a wrinkled capsule.在过度成熟的白内障，晶状体皮质液化。囊内水分可溢出、肿胀消退，体积变小，囊膜发生(fshng)皱缩。,第三十页，共一百零九页。,The dark brown,mature nucleus which sinks inferiorly in the fluid filled capsular sac due to the forces of gravity.is called a Morgagnian cataract.过熟期，棕黄色的晶状体核在囊内因重力而下沉(xi chn)，称为Morgagnian白内障。核下沉可使患者视力突然提高。,第三十一页，共一百零九页。,过熟期,第三十二页，共一百零九页。,hypermature,mature,第三十三页，共一百零九页。,Morganian,第三十四页，共一百零九页。,第三十五页，共一百零九页。,Nuclear cataract,Early onset(after middle age).起病早，一般中年(zhngnin)后开始。The earliest symptom may be improved near vision without glasses(“second sight”).早期症状可能是近视力改善（称为“二次视力”），这是由于白内障初期晶状体核屈光指数增加而产生近视所致。Other symptoms may include poor hue discrimination or monocular diplopia.其他症状可能包括颜色分辨力下降及单眼复视。,第三十六页，共一百零九页。,核性白内障,第三十七页，共一百零九页。,Posterior subcapsular cataract,Located in the cortex near the central posterior capsule.位于后囊下浅皮质(pzh)层。It tends to cause visual symptoms earlier in their development owing to involvement of the visual axis.混浊区位于视轴上，所以早期即可出现视力障碍。Common symptoms include glare and reduced vision under bright lighting conditions.一般症状包括眩光、强光下视力下降。,第三十八页，共一百零九页。,后囊下型白内障,第三十九页，共一百零九页。,Congenital Cataract,Present at birth or appear shortly thereafter.于出生时或于生后短时间内即出现。These cataracts may show many different patterns.The opacity may be confined to the area of the embryonic or fetal nucleus with clear cortex surrounding this.形态学表现各异。混浊可能(knng)限于胎儿核周围。,第四十页，共一百零九页。,Etiology 病因学,Intra-uterine 宫内因素virus infection:风疹病毒(bngd)、巨细胞病毒(bngd)等感染Maternal ingestion of Th