Keratokonus Hastalığında İnsan Korneasının Aşınma Analizi

Year 2021, Issue: 32, 312 - 317, 31.12.2021

Hamid Zamanlou Filiz Karabudak

https://doi.org/10.31590/ejosat.1039221

Abstract

Kornea, gözün ön kısmında bulunan, ışığı odaklamak ve gözü dış etkenlerden korumak için özelleşmiş şeffaf ve kavisli bir dokudur. Korneanın göz ve görme sistemi yapısındaki önemi, şeffaf yapısı nedeniyle çoğu zaman gözden kaçmaktadır. Kornea, retinanın karmaşık nörobiyolojik yapısından ve merceğin dinamik yapısından yoksundur, ancak buna rağmen, gözün bu organında şeffaflık olmadan düzgün bir şekilde çalışamaz. Korneanın şeffaf olmasını sağlayan yapı ve işlevinin karmaşıklığı, görsel sistemin en önemli bileşenlerinden birini incelememize neden olan bir sürprizdir. Kornea, enfeksiyonun yayılmasının önündeki ilk bariyer görevi gören damarsız bir bağ dokusudur. Kornea şeffaflığı, hücresel bileşenlerinin yapısal anatomisi ve fizyolojisi dahil olmak üzere çeşitli faktörlerden kaynaklanmaktadır.
Keratokonus, korneanın deforme olduğu ve koni şeklinde öne çıktığı bir göz rahatsızlığıdır. Korneada meydana gelen bu değişiklik, gelen ışığın görme alanında odaklanamamasına neden olur. Sonuç, bulanık ve çarpık görmedir.
Ayrıca göz ovuşturmanın hastalığın başlangıcında ve ilerlemesinde etkili olabileceğini gösteren çalışmalar da mevcuttur.
Bu çalışmada keratakonus hastalığında göz ovuşturma sonucu oluşan aşınma sonlu elemanlar yöntemiyle incelenmiştir. Korneada deformasyon ve stres analizi araştırılmıştır. SEY, keratakonus hastalığından sonra kornanın biyomekanik davranışını tahmin etmeye yardımcı olabilir.
kontakt noktasında ovuşturma etkisinden dolayı contact basınç, vonmises gerilme ve aşınma en ust değerine ulaşmaktadır

Keywords

Aşınma, Kornea, Sonlu Elemanlar Yöntemi.

Wear Analysis of Human Cornea in Keratoconus Disease

Abstract

The cornea is a transparent and curved tissue located at the front of the eye, specialized to focus light and protect the eye from external factors. The importance of the cornea in the structure of the eye and visual system is often overlooked because of its transparent nature. The cornea lacks the complex neurobiological structure of the retina and the dynamic nature of the lens, but despite this, it is unable to function properly without transparency in this organ of the eye. The complexity of the structure and function of the cornea, which makes it transparent, is a surprise that led us to examine one of the most important components of the visual system. The cornea is a vascular-free connective tissue that serves as the first barrier to the spread of infection to It acts inside the eyeball as well as the building block of the eye wall. Corneal transparency is due to several factors, including the structural anatomy and physiology of its cellular components.
Keratoconus is an eye condition in which the cornea deforms and protrudes forward in a cone shape. This change that occurs in the cornea causes the incoming light to be unable to focus in the visual field. The result is blurred and distorted vision.
There are also studies showing that eye rubbing can be effective in the onset and progression of the disease.
In this study, wear from eye rubbing in kerataconus disease was analyzed by means of finite elements. Deformation and stress analysis in the cornea were investigated. FEM can help to predict biomechanichal behavior of corna after kerataconus dises.
Due to the rubbing effect at the contact point, contact pressure, vonmises stress and wear reach their maximum value.

Keywords

Wear, Cornea, Finite Elements Methods

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