I-retina yinkqantosi engacacanga emgceni ejikeleza iso. Kuphela ngo-0.2 mm ubukhulu kwaye bubukhulu besilivere esiliva. I-retina yenziwe nge-200 million neurons. I-retina iqukethe ii-photoreceptors ezithatha ukukhanya kwaye zithumela loo mqondiso ngentshontsho ye-optic kwingqondo.
Ama-photoreceptors kwi-retina abizwa ngokuba ngamaconga kunye nama-cones.
I-retina yethu iqukethe iigidi eziyi-120 kunye ne-1 million million codereceptors. I-fovea e-macula inexinaniso ephezulu kakhulu yeetonki kunye neentonga azikho ngokupheleleyo. Amaconsi ahambisa isisombululo esilungileyo semifanekiso kodwa iindonga zizona zixhobo ezingcono. Yingakho xa ukhangele ngqo kwenkwenkwezi ebusuku, kubonakala ngathi bubude kakhulu, kodwa ukuba ukhangele ngqo kwicala leenkwenkwezi, kukhanya ngakumbi kwaye kubonakala ngakumbi.
Kunjengefilimu kwikhamera, imifanekiso ivela kwi-lens yelanga kwaye igxile kwi-retina. I-retina iguqulela le mizobo kumbane kagesi kwaye ibathumela kwingqondo.
Xa ugqirha ugxotha amehlo akho ngexesha lokuhlolwa kwamehlo okubanzi , kuthiwa ukhangele i-fundus. I-fundus ichazwa ngamacandelo alandelayo:
- I-posterior pole - ipolisi yangemva kwinqanaba le-retina kwaye liquka i-nertic optic kunye ne-macula
- Intloko ye -nertic optic - Intloko ye-optic ye-optic isifo se-optic nerve njengoko ingena ngasemva kweso. Yenziwe ngezigidi zamagqabhagqabha enesibindi kwaye idlulisela ulwazi olubonakalayo kwingqondo ekusebenziseni.
- I-Macula - I-macula iyinxalenye ekhethiweyo ye-retina ngaphakathi kwinqanaba le-retina elinika umbono ophakathi. Ephakathi kwendawo ye-macula yi-fovea. I-fovea inommandla wobuninzi obubonakalayo.
- I-Equator kunye ne-retina yomda we-pipeline - Le ndawo yindawo ye-retina njengoko iphuma kwipolisi engemva.
- I-Ora serrata - I-ora serrata yindawo engamanzi phakathi kwe-retina kunye nomzimba we-ciliary. Le ngqungquthela ibonisa ukutshintshwa kwendawo engabonakaliyo ye-retina kwiindawo ezibonakalayo ze-retina.
Iingxaki eziqhelekileyo ze-Retina
- I-retinal tear or detachment - I- retinal tear or detachment ithathwa njengesiphumo esiphuthumayo apho i-retina ekhanyayo ichithwe okanye ikhutshwe kude emva kweso elondla oksijini kunye nokutya.
- I-retinopathy yesifo sikashukela - I-retinopathy yesifo sikashukela ivela kubantu abanesifo sikashukela xa imithwalo yegazi ivuza igazi kunye ne-fluid. Ngamanye amaxesha imitsha yegazi entsha ikhula ibe yingozi kwaye ingabangela ukulahleka kombono, i-glaucoma, kunye ne-retinal detachment ukuba ingaphathwa.
- I-retinopathy yeCentral serous - I-retinopathy ye-central central is aqhelekileyo imeko apho i-retina ephakathi yenza i-cyst kunye nombono ongundoqo.
- Ukuchithwa kweMacular - Ukuhlaselwa kweMicrophe isifo se-macula apho kukho ukulahleka phakathi kwendawo yombono. Ukutshintshwa kwee-macular pigmentary kwenzeka kwaye imilambo yegazi ephosakeleyo ikhula phantsi kwe-macula. Ukulahleka kombono kunokuba ngumnene kakhulu kunzima kakhulu.