我們正常人的(de)眼(yan)(yan)瞼能(neng)不停地關閉與睜開，是(shi)因為依(yi)賴于上眼(yan)(yan)瞼深部(bu)(bu)(bu)的(de)上瞼提(ti)肌來(lai)完成(cheng)(cheng)的(de)，上瞼提(ti)肌受(shou)動眼(yan)(yan)神經(jing)支(zhi)配。當上瞼提(ti)肌功能(neng)不全(quan)(quan)(quan)或(huo)喪(sang)失，可(ke)使上瞼呈部(bu)(bu)(bu)分(fen)或(huo)全(quan)(quan)(quan)部(bu)(bu)(bu)下垂(chui)。輕者遮蓋(gai)(gai)部(bu)(bu)(bu)分(fen)瞳(tong)孔，嚴(yan)重(zhong)者可(ke)將全(quan)(quan)(quan)部(bu)(bu)(bu)瞳(tong)孔遮蓋(gai)(gai)，不但影響視(shi)力(li)和美觀，時間(jian)長了還會造(zao)成(cheng)(cheng)弱視(shi)。有(you)些(xie)雙眼(yan)(yan)下垂(chui)的(de)兒童，為了增加(jia)視(shi)野范圍，常有(you)頭部(bu)(bu)(bu)后(hou)(hou)仰(yang)視(shi)物的(de)特殊姿態。上瞼下垂(chui)可(ke)以是(shi)單(dan)側或(huo)雙側的(de)，也可(ke)以是(shi)先天性(xing)或(huo)后(hou)(hou)天性(xing)的(de)，病因較復雜。
一、 先(xian)天性上瞼下垂
先天(tian)性上(shang)瞼(jian)(jian)下垂(chui)一般(ban)為(wei)雙側(ce)性的，但也有(you)單側(ce)性的、遺傳性的，主要(yao)為(wei)上(shang)瞼(jian)(jian)提肌(ji)或動(dong)(dong)眼(yan)神經發(fa)育(yu)不全(quan)所致。單純上(shang)瞼(jian)(jian)下垂(chui)系上(shang)瞼(jian)(jian)提肌(ji)發(fa)育(yu)不全(quan)，占其上(shang)瞼(jian)(jian)下垂(chui)的大多(duo)數，少數是因(yin)動(dong)(dong)眼(yan)神經核發(fa)育(yu)不全(quan)的緣(yuan)故。動(dong)(dong)眼(yan)神經核發(fa)育(yu)不全(quan)除上(shang)瞼(jian)(jian)下垂(chui)外還有(you)眼(yan)球上(shang)轉動(dong)(dong)能力受限，給上(shang)瞼(jian)(jian)下垂(chui)手術治(zhi)療帶來困難(nan)。還有(you)一些上(shang)瞼(jian)(jian)下垂(chui)合并有(you)內眥贅(zhui)皮(pi)、小(xiao)瞼(jian)(jian)裂(lie)、鼻(bi)梁低平，稱瞼(jian)(jian)裂(lie)狹(xia)小(xiao)綜合癥。
二(er)、后天性(xing)上瞼下垂
后天性上瞼(jian)下(xia)垂可根據(ju)病因分為：①外傷性，如眼(yan)(yan)(yan)瞼(jian)撕裂，傷及(ji)上瞼(jian)提肌;②某(mou)些(xie)疾病如重(zhong)癥肌無力(li)，眼(yan)(yan)(yan)眶炎癥、出血(xue)和眼(yan)(yan)(yan)眶腫瘤等;③眼(yan)(yan)(yan)瞼(jian)結構(gou)變(bian)化，如沙眼(yan)(yan)(yan)引(yin)起瞼(jian)板增厚、眼(yan)(yan)(yan)瞼(jian)腫痛，眼(yan)(yan)(yan)球摘除術后、小眼(yan)(yan)(yan)球、眼(yan)(yan)(yan)球萎縮、眼(yan)(yan)(yan)球內陷、老年人眶脂肪萎縮等，造成對上瞼(jian)缺乏(fa)正常支(zhi)持而引(yin)起下(xia)垂。
專家提示(shi)：有眼瞼下垂癥狀或感覺不適時，請及時就(jiu)診。
咨(zi)詢電話(hua)： 4007-008-009