Common Visual Problem Caused By Misshapen Cornea or Lens

Normal Vision

Normal vision begins with light, visible light is a band of energy within the electromagnetic spectrum the wavelength of this light determines the colors in the spectrum (Goldstein, p. 22, 2014). Within the eyes themselves are the receptors for vision, light is reflected on objects in the environment and enters the eye through the pupil and is then focused in the cornea and lens, and finally forms a sharp image in the retina (Goldstein, p.23, 2014). There is a network of neurons that the signals from these receptors flow through that are located in the optic nerve in the back of the eye that sense signals toward the brain.

Light is the stimulus for vision, the ability to see an object begins with the visible light, this light stimulates the entire process of vision. Once the light reaches the optic nerve at the back of the eye, signals are sent to the brain. From there the receptors and neurons in the receptor lining make two transformations that shape what we see; transforms the light reflected from the object into an image of that object and the transformation from the image to electrical signals (Goldstein, p. 23, 2014).

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How Vision Works

This is a simple diagram that shows how light is reflected back to our eye and begins the process of vision (Kumar, n.d.)

Vision With Astigmatism

When a person has astigmatism their cornea has an irregular curve, impacting the way in which light refracts to their retina (Kivi & Boskey, 2015). This change in light refraction causes blurry, distorted or fuzzy vision. There are two types of astigmatism, corneal is when the cornea is misshapen and lenticular is when your lens is misshapen (Kivi & Boskey, 2015).

Visual Perception

Incoming stimuli are grouped together to create our perception of objects by organizing them into coherent unites, which involves both grouping and segregation (Goldstein,p. 100, 2014). When we look at an object we will either segregate it based upon differences, for example we will look at two trees and separate them because one is in front of the other. Grouping things together happens when we would put all of the grass together in our mind because it is all green and in an area together. According to Gestalt theorists he whole is different than the sum of its parts which came from the idea that apparent movement cannot be explained by sensations (Goldstein, p. 101, 2014). The central principle of Gestalts psychology states that every stimulus pattern is seen in a way that the resulting structure is as simple as possible (Goldstein,p. 102, 2014).

Vision Difference With and Without Astigmatism

This image gives an idea of what it may be like to see life through the eyes of someone with Astigmatism compared to someone who does not have Astigmatism. (Airoptix, n.d.)
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Treatment Options For Astigmatism

A person with astigmatism can receive an intraocular lens implantation that could replace the lens issues that they currently have related to the Astigmatism (Farooqui et al., 2015). These new lenses are made to filter blue light using a blue light filtering technology and are surgically implanted to replace lenses that are misshapen for those with Astigmatism as well as cataract. Corrective lenses are also another treatment for astigmatism in the form of both eyeglasses and contact lenses.
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Anatomy Of The Eye

This photo is a great start for understanding the anatomy of the eye, it is easy to look at this image and see what parts of the eye are impacted by Astigmatism.

(Eye Clinic of Sandpoint, n.d.)


Airoptix. (n.d.). Retrieved from

Eye Clinic of Standpoint. (n.d.). The Visual Process. Retrieved from

Farooqui, J.H., Koul, A., Dutta, R., & Shroff, N.M. (2015). Management of Moderate and Severe Corneal Astigmatism With Acrosof Toric Intraocular Lens Implantation- Our Experience. Elsevier. Retrieved from

Kivi, R. & Boskey, E. (2015). Astigmatism. Healthline. Retrieved from

Kumar, V. (n.d.). How Vision Works. Retrieved from