Astigmatism
Stephany Hitchcock
The Normal Eye
When light bounces off of an object it enters the eye through the Cornea (AOA, 2015). Once it hits the Cornea the Cornea then bends the light or it refracts the light from the object (AOA, 2015). The light then goes through the pupil, which dilates allowing a certain amount of the light to pass through (AOA,2015). Look at Diagram 1 (D1) below.
D1
This is a diagram of what the structure of a normal eye would look like.
D2
This is a diagram of the difference between a normal eye and an eye the had Astigmatism.
D3
This is a picture of what and actual eye would look like if the person has Astigmatism.
Thoery of Perception
Class Room
This is a "whole" picture of what a person would see as a class room.
Parts
This is a picture of the "broken" parts of a class room. When we are asked to look at what makes up a "whole" class room.
Astigmatism
Astigmatism is when "the lens of the eye or the cornea, which is the front surface of the eye, has an irregular curve" (Kivi, & Boskey, 2015). The above diagram (D2) shows a comparison of what a normal Cornea looks like and what a persons Cornea would look like with Astigmatism, Diagram 3 (D3) shows an actual picture of a persons eye with Astigmatism. The irregular curve of the Cornea can cause a change in the way that the light is refracted or the way that it passes through (Kivi, & Boskey, 2015). With the curvature of the Cornea or lens the light is not able to properly hit the eyes Retina (AOA, 2015).
Problems, Types, and Causes
Astigmatism can cause a persons vision to become blurry, fuzzy and even distorted (Kivi, & Boskey, 2015). There are two different types of Astigmatism that a person could have, there is Corneal Astigmatism which "happens when your cornea is misshapen" (Kivi, & Boskey, 2015). As well as Lenticular Astigmatism which "happens when your lens is misshapen" (Kivi, & Boskey, 2015). Astigmatism can caused from a couple different factors. A person can be born with it, develop it over a lifetime, or it can be brought on by injury to the eye.
Treatments
There are several different ways that Astigmatism can be treated such as; eyeglasses, contact lenses, orthokeratology, and laser and other refractive surgery procedures (AOA, 2015). Eyeglasses and contact lenses are what people choose to normally go with to correct Astigmatism. If the condition is really bad they may chose to go a different route. Orthokeratology "involves the fitting of a series of rigid contact lenses to reshape the cornea, the front outer cover of the eye" (AOA, 2015). If these three options do not work then the person may opt to go with surgery to permanently correct the condition (AOA, 2015).
Reference
American Optometric Association. (2015). Astigmatism. Retrieved from http://www.aoa.org/patients-and-public/eye-and-vision-problems/glossary-of-eye-and-vision-conditions/astigmatism?sso=y
American Optometric Association. (2015). How Your Eyes Work. Retrieved from http://www.aoa.org/patients-and-public/resources-for-teachers/how-your-eyes-work?sso=y
Astigmatism. (n.d). Astigmatism Eye Chart. Retrieved from https://www.google.com/search?as_st=y&tbm=isch&hl=en&as_q=astigmatism&as_epq=&as_oq=&as_eq=&cr=&as_sitesearch=&safe=images&tbs=sur:f#as_st=y&hl=en&tbs=sur:f&tbm=isch&q=astigmatism+eye&imgrc=UR_ceLol2O7urM%3A
Gestalt Theory. (n.d). Gestalt Theory of Visual Perception. Retrieved from http://www.users.totalise.co.uk/~kbroom/Lectures/gestalt.htm
Iris. (n.d). Structures of the Eye. Retrieved from https://www.google.com/search?as_st=y&tbm=isch&hl=en&as_q=the+eye+diagram&as_epq=&as_oq=&as_eq=&cr=&as_sitesearch=&safe=images&tbs=sur:f#imgrc=qPwl--sEp7DAsM%3A
Keratoconus. (n.d). Keratoconus Eye. Retrieved from https://www.google.com/search?as_st=y&tbm=isch&hl=en&as_q=astigmatism&as_epq=&as_oq=&as_eq=&cr=&as_sitesearch=&safe=images&tbs=sur:f#as_st=y&hl=en&tbs=sur:f&tbm=isch&q=astigmatism+eye&imgrc=dPNKK9LBY_6O5M%3A
Kivi, R. & Boskey, E. (2015). Astigmatism. Retrieved from http://www.healthline.com/health/astigmatism#Overview1