I-Ametropia ichazwa ngokungabi bikho kobukhali embonweni weso. Kuhlobene eduze nokuntuleka kokuhlangana kwemishayo yokukhanya ku-retina, ne-myopia, i-hyperopia, noma i-presbyopia njengembangela.

Izimbangela ze-ametropia ngokuvamile ukukhubazeka kweso kanye nezingxenye zalo zangaphakathi, ezihlobene nokukhubazeka noma ukuguga kunezifo. Indima yeso ngempela ukufeza ukuhlangana kwemisebe yokukhanya evela ezintweni ezisizungezile endaweni okugxilwe kuyo. Lapho konke sekuphelele, sikhuluma ngakhoi-emmetropia. THE 'i-ametropia ngakho-ke ichaza ukuchezuka kwemisebe yokukhanya.

Lokhu kuchezuka kuxhunywe kumapharamitha amabili. Ngakolunye uhlangothi, ukuphambuka kwemisebe yokukhanya, okwenziwa yi- cornea futhi i-crystalline, amalensi amabili e-biconvex. Ngakolunye uhlangothi, ukujula kwesokhethi yamehlo. Inhloso yonke iwukugxilisa imisebe ngqo ku-retina, endaweni yayo ebucayi kakhulu ebizwa ngokuthi macula, ngenxa yalokhu, kuyadingeka ukuphambukisa kahle i-beam yokufaka, futhi ube ne-retina ebangeni elihle.

Ngakho-ke, izimbangela ezihlukene ze-ametropia zikhona ukukhubazeka kwe-lens, i-cornea, noma ukujula kwebhola leso.

Kunezimpawu ezahlukene zei-ametropia, esimweni ngasinye sokungafani. Ngayinye yazo ingahambisana nezinye izimpawu ezihlobene nokungaboni kahle: ikhanda elibuhlungu, ukucindezeleka kwamehlo, ubunzima bamehlo.

• Ukubona okufiphele ukusuka kude: la myopia

Uma i-lens yeso igxilisa imisebe yokukhanya kusenesikhathi, ngenxa yamandlaindawo yokuhlala likhulu kakhulu, noma iso lijule kakhulu, sikhuluma nge-myopia. Kulesi simo, iso elibona eduze ngeke libone ngokucacile likude, njengoba imisebe yezinto ezikude izogxiliswa ngokushesha kakhulu. Ngakho-ke isithombe sabo sizofiphala ku-retina.

• Ukubona okufiphele eduze: thehyperopia

Uma i-lens yeso igxilisa imisebe yokukhanya sekwephuzile kakhulu, noma iso lingashoni ngokwanele, kubizwa ngokuthi iso elibukhali. Kulokhu, ukubona kude kungenziwa ngendawo encane ye-lens, ukuze kugxilwe imisebe ku-retina. Ngakolunye uhlangothi, izinto eziseduze ngeke zikwazi ukugxila ku-retina. Ngakho-ke indawo okugxilwe kuyo izoba ngemva kweso, futhi isithombe esiku-retina sizofiphala.

• Umbono ufiphazwe ngobudala: La presbyopia

Ngenxa yokuguga kwemvelo kweso, i i-crystalline, obhekene nokuhlaliswa kweso futhi ngenxa yalokho ubukhali bombono, kancane kancane uzolahlekelwa ukunwebeka nokuqina kwawo. Ngakho-ke kuzoba nzima kakhulu, uma kungenzeki, ukwenza isithombe sicace uma siseduze kakhulu. Yingakho ngokuvamile uphawu lokuqala lwe-presbyopia "ukufinyelela" ukuze ubone kangcono! Ivame ukubonakala cishe eminyakeni engama-45 ubudala.

• Umbono osontekile, izinhlamvu eziyimpinda: theI-Astigmatism

Uma i-cornea yeso, futhi ngezinye izikhathi i-lens, ihlanekezelwe, khona-ke imisebe yokukhanya engenayo nayo izophambuka, noma iphindwe kabili. Ngenxa yalokho, isithombe esiku-retina sizoba nokungabukeki kahle, eduze nakude. Labo abathintekile babona kabili, ngokuvamile abafiphele. I-Astigmatism ingaba ngenxa yokukhubazeka kokuzalwa, ne-cornea emise okweqanda ebizwa ngokuthi "ibhola lombhoxo" esikhundleni sokuba yindilinga, noma ngenxa yesifo esifana ne-oval. i-keratocone.

Ukwelashwa kwe-ametropia kuncike emsuka nezici zayo. Singazama ukuguqula imisebe engena esweni, sisebenzisa izibuko namalensi, noma sisebenze ukuze sishintshe ukwakheka kwalo kwangaphakathi.

Ukuntuleka kokuvimbela

Izimo ezihlukahlukene ze-ametropia zixhunyaniswa nokuthuthukiswa komzimba, ngakho-ke azikho izindlela zokuvimbela ukuvimbela, isibonelo, i-myopia. Izinsalela ezifanele, ezinganeni ezincane, ukuze zithole ngokushesha izimpawu zokuqala ze-ametropia ukuze zithole isisombululo.

Izibuko namalensi

Isixazululo esivame kakhulu ekwelapheni i-ametropia ukugqoka izibuko noma amalensi okuxhumana, ukuze abekwe ngqo ku-cornea. Ngakho, ku-myopia, i-hyperopia, noma i-presbyopia, ukugqoka amalensi okulungisa kwenza kube nokwenzeka ukuguqula i-engeli yemisebe yokukhanya kokokufaka. Lokhu okokunxephezela ukusilela ku-cornea noma ilensi, kanye nokuqinisekisa ukuthi imisebe igxila njengoba ihloselwe i-retina, kunokuba ibe phambi kwayo noma ngemuva kwayo.

Ukwelapha okuhlinzwa

Kukhona futhi izindlela zokwelapha ezihlukene zokuhlinza, inhloso yakho ukulimala kweso. Umqondo uwukushintsha ukugoba kwe-cornea, imvamisa ngokususa ungqimba kuyo nge-laser.

Ukuhlinza okuthathu okuyinhloko imi kanje

• Lasik, esetshenziswa kakhulu

Ukusebenza kwe-LASIK (ye- ” Ukuphindaphinda kwe-Laser-Assisted in-situ ») kuhlanganisa ukusika i-cornea usebenzisa i-laser ukususa ukujiya okuncane. Lokhu kushintsha ukugoba kwe-cornea futhi kunxephezele amaphutha ku-lens.

• PRK, ubuchwepheshe obuningi

Ukusebenza kwe-PRK, i-photorefractive keratectomy, isebenzisa indlela efanayo ne-LASIK kodwa ngokukhipha izingcezu ezincane ebusweni be-cornea.

• Amalensi e-intro-ocular

Intuthuko ekuhlinzweni kwamehlo yenza kube nokwenzeka ukufaka ama-lens "unomphela" ngokuqondile ngaphansi kwe-cornea (engasuswa ngesikhathi sokusebenza okusha).