【正文】
zhu243。)的部位,老年性白內(nèi)障分為3種類型:皮質(zhì)性、核性及后囊下白內(nèi)障。一個晶狀體可能同時發(fā)生這3型白內(nèi)障。,第二十頁,共一百零九頁。,第二十一頁,共一百零九頁。,第二十二頁,共一百零九頁。,Cortical cataract,the most common type of agerelated cataract. four stages as follows:,第二十三頁,共一百零九頁。,Incipient stage 初發(fā)期,Cortical changes may begin as small peripheral water clefts. 皮質(zhì)中空泡和水隙形成。 Radical pattern opacity. 放射狀混濁。 檢眼鏡檢查可見(kěji224。n)紅光反射中放射狀或片狀陰影。 早期較周邊的混濁并不影響視力,病程發(fā)展慢。,第二十四頁,共一百零九頁。,初發(fā)期,第二十五頁,共一百零九頁。,Intumescent stage 腫脹(zhǒngzh224。ng)期,The lens takes up water, it becomes intumescent. 混濁加重,皮質(zhì)吸水腫脹,晶狀體體積增大。 Anterior chamber gets shallow. 前房變淺,有閉角型青光眼體質(zhì)者可誘發(fā)青光眼急性發(fā)作。 斜照法檢查虹膜投影(t243。uyǐng)現(xiàn)象。 視力明顯下降,眼底難以窺清。,第二十六頁,共一百零九頁。,腫脹(zhǒngzh224。ng)期,第二十七頁,共一百零九頁。,Mature stage 成熟期,Liquid escapes and the lens shrinks. 晶體內(nèi)水分溢出,腫脹消退,體積變小。 The lens protein is totally opaque. 晶體完全(w225。nqu225。n)混濁,呈乳白色。 視力降至手動或光感,眼底不能窺入。,第二十八頁,共一百零九頁。,成熟期,第二十九頁,共一百零九頁。,Hypermature Stage 過熟期,A longstanding 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. 在過度成熟的白內(nèi)障,晶狀體皮質(zhì)液化。囊內(nèi)水分可溢 出、腫脹消退,體積變小,囊膜發(fā)生(fāshēng)皺縮。,第三十頁,共一百零九頁。,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. 過熟期,棕黃色的晶狀體核在囊內(nèi)因重力而下沉(xi224。 ch233。n),稱 為Morgagnian白內(nèi)障。 核下沉可使患者視力突然提高。,第三十一頁,共一百零九頁。,過熟期,第三十二頁,共一百零九頁。,hypermature,mature,第三十三頁,共一百零九頁。,Morganian,第三十四頁,共一百零九頁。,第三十五頁,共一百零九頁。,Nuclear cataract,Early onset (after middle age). 起病早,一般中年(zhōngni225。n)后開始。 The earliest symptom may be improved near vision without glasses (“second sight”). 早期癥狀可能是近視力改善(稱為“二次視力”),這是由于白內(nèi)障初期晶狀體核屈光指數(shù)增加而產(chǎn)生近視所致。 Other symptoms may include poor hue discrimination or monocular diplopia. 其他癥狀可能包括顏色分辨力下降及單眼復(fù)視。,第三十六頁,共一百零九頁。,核性白內(nèi)障,第三十七頁,共一百零九頁。,Posterior subcapsular cataract,Located in the cortex near the central posterior capsule. 位于后囊下淺皮質(zhì)(p237。zh236。)層。 It tends to cause visual symptoms earlier in their development owing to involvement of the visual axis. 混濁區(qū)位于視軸上,所以早期即可出現(xiàn)視力障礙。 Common symptoms include glare and reduced vision under bright lighting conditions. 一般癥狀包括眩光、強(qiáng)光下視力下降。,第三十八頁,共一百零九頁。,后囊下型白內(nèi)障,第三十九頁,共一百零九頁。,Congenital Cataract,Present at birth or appear shortly thereafter. 于出生時或于生后短時間內(nèi)即出現(xiàn)。 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. 形態(tài)學(xué)表現(xiàn)各異?;鞚峥赡?kěn233。ng)限于胎兒核周圍。,第四十頁,共一百零九頁。,Etiology 病因?qū)W,Intrauterine 宮內(nèi)因素 virus infection: 風(fēng)疹病毒(b236。ngd)、巨細(xì)胞病毒(b236。ngd)等感染 Maternal ingestion of Thalidomide, steroids,… 孕期服用某些藥物 Hereditary 遺傳因素 autosomal dominant 常染色體顯性遺傳多見 recessive;Xlinked 隱性和伴性遺傳,第四十一頁,共一百零九頁。,第四十二頁,