Okubalulekile kwe-Eye Anatomy
Iso lomuntu liyilungu elibona ukukhanya futhi lithumela izibonakaliso eduze kwenduku yokukhanya ebuchosheni. Mhlawumbe enye yezitho eziyinkimbinkimbi kakhulu zomzimba, iso lenziwe izingxenye eziningana. Futhi ingxenye ngayinye ngayinye inika amandla ekuboneni kwakho.
> Bheka isimo esithinta amehlo.
Cornea
I-cornea yiyona ebonakalayo, isakhiwo esifana ne-dome engxenyeni engaphambili yeso. Inikeza iso lesithathu kwezintathu zokugxila noma ukuguqula amandla.
Ingxenye yesithathu ikhiqizwa i-lens yangaphakathi yama-crystalline. Ngokufana ne-lens yekhamera, i-cornea isiza ukugxila ekukhanyeni kufinyelele esweni ku-retina.
I-cornea nayo igcwele izinzwa ezisixwayisa ukucasuka okungase kulimaze umbono wethu nempilo yeso. Futhi i-cornea iyakwazi ukulimala. Uma uphenya iso lakho, empeleni ukhanse i-cornea yakho. Amanxeba amancane avumayo avame ukuphulukisa eyedwa, kodwa ukulimala okujulile kungabangela ubuhlungu futhi ngezinye izikhathi kutholakala ukonakala komzimba.
Ukuqothuka kwe-corneal kungabangela ubungozi e-cornea engonakalisa umbono wakho. Uma ubheka iso lakho ngokuphawulekayo, kubalulekile ukubona udokotela weso. Udokotela wezilanga angabuka i-cornea ngaphansi kwe-biomicroscope yesibani esitsheni.
Umfundi
Umfundi ungumgodi noma ukuvulwa okuphakathi nendawo ye-iris yeso. Umfundi ulawula isibalo sokukhanya esingena esweni. Usayizi wamfundi ulawulwa yi-dilator ne-sphincter imisipha ye-iris.
Umsebenzi womfundi ufana kakhulu nokuvula ikhamera okuvumela ukukhanya okungaphezulu ukuze kuvezwe okwengeziwe. Ebusuku, abafundi bethu bahlanza ukuvumela ukukhanya okwengeziwe ukuze sikhulise umbono wethu.
Kubantu, umfundi ujikelezile. Ezinye izilwane zinezingane ezihlanzile lapho abanye bebafundi abahamba phambili. Abafundi bavela abamnyama ngoba ukukhanya okungena esweni kukhishwa kakhulu yizicubu ngaphakathi kweso.
Iris
Iris yiyona ingxenye enemibala yeso elilawula isibalo sokukhanya esingena esweni. Yingxenye ebonakalayo kakhulu iso. Ilala phambi kwe-crystalline lens futhi ihlukanisa ikamelo langaphakathi ukusuka ekamelweni eliphansi.
Iris iyingxenye ye-uveal tract-ungqimba ophakathi odongeni leso. Leli pheshana lihlanganisa umzimba we-ciliary, isakhiwo esweni elithumela uketshezi olucacile olubizwa ngokuthi i-aqueous humor.
Umbala we-Iris uxhomeke enani le- melanin pigment ku-iris. Umuntu onamehlo ensundu unombala ofanayo we-melanin pigment ukuthi umuntu onamehlo aluhlaza okwesibhakabhaka. Noma kunjalo, umuntu onamabala aluhlaza okwesibhakabhaka unemibala engaphansi kakhulu.
I-Crystalline Lens
I-crystalline lens iyisakhiwo esibonakalayo esweni elimiswe ngokushesha ngemva kwe-iris-eliletha imisebe yokukhanya ukugxila kwi-retina.
Imisipha encane ehlanganiswe lens ingenza ishintshe isimo esivumela iso ukuba ligxile ezintweni eziseduze noma ezikude.
Ngokuhamba kwesikhathi, i-lens ilahlekelwa ukuqina kwayo. Lokhu kubangela ukuba iso lilahlekelwe ezinye zekhono layo lokugxila ezintweni eziseduze. Lesi simo siyaziwa njenge-presbyopia futhi ngokuvamile siveza izinkinga ngokufunda, cishe eminyakeni engama-40 ubudala.
I- cataract i-clouding ye-lens futhi yinto evamile ehambisana nokuguga. Ngenhlanhla, i-cataracts ikhula kancane futhi ingase ingathinti umbono wakho iminyaka eminingana. Ngeminyaka engu-65, abangaphezu kwamaphesenti angu-90 abantu abanesifo se-cataract. Ukwelashwa kwe-Cataract kuhilela ukukhipha i-lens efikelwe ukugcoba nokuyibeka endaweni ene-lens intraocular engenawo.
I-Humor Aqueous
Ihlaya elimnandi lihlanzekile, amanzi amanzi afakwe ngemuva kwe-cornea. Kuyasiza ukuletha izakhi emathangeni eso. Yakhiwa ngemuva kwe-lens futhi igeleza phambi kweso ukugcina ingcindezi ngaphakathi kweso. Izinkinga nge-fluid aqueous zingabangela izinkinga ezihilela ukucindezeleka kweso, njenge- glaucoma .
I-Vitreous Humor
I-vitreous humor, ephikisana ne-retina, yenza ingxenye enkulu yeso. Kuyinto into efana ne-jelly egcwalisa ngaphakathi kweso. Yenziwe kakhulu ngamanzi, i-vitreous fluid inikeza iso iso layo. Yakhiwa ngamanzi, i-collagen, namaphrotheni futhi iqukethe amaseli azosiza ukugcina ukucaca kwalo.
Njengoba sikhula, i-vitreous humor iyaqina. Lolu shintsho ngezinye izikhathi lubangele ukuthi ludonte ku-retina. Uma amandla okudonsa eba namandla ngokwanele, ama-vitreous amahlaya angase ahlukane ne-retina. Lokhu kubizwa ngokuthi i- posterior vitreous detachment , njengoba kuvame ukuvela ngemuva (ngemuva) kokuya kweso.
I-Retina
Kutholakala ngaphakathi kweso, i-retina yindawo ekhanyayo ekhona ngemuva kwamehlo ukuthi i-lens igxila ezintweni, futhi yenza umbono ubonakale. I-retina yenziwe ngezigaba eziyishumi ezincane kakhulu. Phakathi kwalezi zingxenye kukhona izinduku nama-cones asetshenziselwa ukuthola umbala.
I-retina iyinkimbinkimbi kakhulu. I- retina ehlanganisiwe ivela lapho i-retina ihlukaniswa nezinye izakhiwo zeso.
Ngokuvamile kwenzeka ngesikhathi semidlalo yokuxhumana noma ngenxa yengozi. Inqola yokutakula ingozi ejulile edinga ukunakekelwa okusheshayo ngomsebenzi wokunakekela iso.
Sclera
I-sclera yeso iyaziwa kangcono ngokuthi "umhlophe weso." Ngenkathi singabona kuphela ingxenye ebonakalayo ye-sclera, empeleni iyasizungezile lonke iso. Kuyisigxobo esinezinyosi eziqukethe ukusebenza kwangaphakathi okwenza umbono ubonakale. Ibuye ijabule ngesimo esiyindilinga.
I-scleritis i-inflammation ye-sclera. Kungabangela ubuhlungu obukhulu beso, ukubomvu nokulahlekelwa umbono kwabanye abantu. Kungabuye kuhlotshaniswe nokuhlukunyezwa noma ukutheleleka-okungaphezulu kwengxenye yesigameko se-scleritis kuhlotshaniswa nesifo esiyisisekelo se-systemic.
> Imithombo:
> Amehlo Akho Asebenza Kanjani? Iwebhusayithi ye-National Eye Institute.
> Iso. Iwebhusayithi ye-University of Michigan Kellogg Eye Center.