I-Astigmatism: kuyini?

I-Astigmatism yisimo esingavamile se-cornea. Uma kwenzeka i-astigmatism, i-cornea (= ulwelwesi olungaphezulu lweso) i-oval esikhundleni sokuba yindilinga kakhulu. Sikhuluma nge-cornea emise "njengebhola lombhoxo". Ngenxa yalokho, imisebe yokukhanya ayihlangani endaweni eyodwa nefanayo ye-retina, ekhiqiza isithombe esihlanekezelwe futhi ngenxa yalokho angaboni kahle eduze nakude. Ukubona kuba nzima kuwo wonke amabanga.

I-Astigmatism ivame kakhulu. Uma lesi sici sokubona sibuthakathaka, ukubona kungase kungaphazamiseki. Kulokhu, i-astigmatism ayidingi ukulungiswa ngezibuko noma amalensi okuxhumana. Ibhekwa njengebuthakathaka phakathi kuka-0 no-1 diopters futhi inamandla ngaphezu kwama-diopter angu-2.

I-Astigmatism ingenzeka kusukela ekuzalweni. Kamuva, ingase ihlotshaniswe nezinye iziyaluyalu ze-refraction ezifana ne-myopia noma i-hyperopia. I-astigmatism ingavela futhi kulandela i-keratoconus, isifo esiwohlokayo esivame ukuvela ebusheni futhi lapho i-cornea ithatha isimo se-cone, okubangela i-astigmatism enzima nokuncipha kokubona kahle. Qaphela ukuthi i-astigmatism ayiyona eyesikhashana futhi ingaba yimbi kakhulu ngokuhamba kwesikhathi.

Abantu abane-astigmatism bangadida izinhlamvu ezithile ezifana no-H, M no-N noma ngisho no-E kanye no-B. Ngakho-ke i-astigmatism kufanele ihlonzwe kusenesikhathi futhi ikakhulukazi, ngaphambi kokufunda ukufunda.

Nakuba i-corneal astigmatism ivame kakhulu, kune-astigmatism yangaphakathi lapho ukuguqulwa kungaphazamisi i-cornea kodwa ilensi etholakala ngaphakathi kweso. Uma ukukhubazeka okubili kuhlotshaniswa, khona-ke sikhuluma nge-astigmatism ephelele.

Ukuvama

I-Astigmatism ivame kakhulu. Bangaphezu kwezigidi ezingu-15 abantu baseFrance okuthiwa bane-astigmatic. Ucwaningo¹ olwenziwa e-United States ukuchaza ukusabalala kwephutha le-refractive liphakamise ukuthi ngaphezu kwe-30% yabahlanganyeli bahlushwa i-astigmatism. Ukusabalala kuzofana naseCanada.

kwesifo

Ukuxilongwa kwe-astigmatism kwenziwa yi-ophthalmologist noma i-optometrist. Owokugcina uhlola umbono, eduze nakude, bese usebenzisa i-refractometer, ukala i-radii yokugoba kwe-cornea ezoqinisekisa ukuba khona kwe-astigmatism.

Izimbangela

I-Astigmatism ngokuvamile ivela kusukela ekuzalweni. Izimbangela zokuvela kwayo okwamanje azaziwa. Ngezinye izikhathi, ukuhlinzwa kwe-cataract ngokwesibonelo, noma ukufakelwa kwe-cornea kungalimaza futhi kubangele i-astigmatism. Ukutheleleka noma ukulimala esweni nakho kungaba necala.

Izinkinga

I-Astigmatism ingabangela i-amblyopia, okungukuthi ukuncipha kokubona kwelinye lala mehlo amabili okubangelwa ukungavamile ekukhuleni kombono phakathi nengane (isb. i-strabismus, i-cataract yokuzalwa, njll.) .