Eye Diagram

1. posterior compartment
2. ora serrata
3. ciliary muscle
4. ciliary zonules
5. canal of Schlemm
6. pupil
7. anterior chamber
8. cornea
9. iris
10. lens cortex
11. lens nucleus
12. ciliary process
13. conjunctiva
14. inferior oblique muscule
15. inferior rectus muscule
16. medial rectus muscle
17. retinal arteries and veins
18. optic disc
19. dura mater
20. central retinal artery
21. central retinal vein
22. optical nerve
23. vorticose vein
24. bulbar sheath
25. macula
26. fovea
27.sclera
28. choroid
29. superior rectus muscle
30. retina

 

 

Parts of the Eye

  • Vitreous Gel: A clear gel that fills the inside of the eye. The vitreous is a common source of floating spots in your vision.  If you see new floaters, contact your eye doctor immediately. 
  • Optic Nerve: A bundle of more than one million nerve fibers that carries visual messages from the retina to the brain. Glaucoma is a common optic nerve disease, a progressive cell death of the optic nerve fibers – commonly caused by increased pressure in the eye. 
  • Macula: The small sensitive area of the retina that gives central vision. It is located in the center of the retina and contains the fovea. Nearly 1 in 4 persons over the age of 65 have some degeneration of their maculae.
  • Fovea: The center of the macula and gives the sharpest vision.
  • Retina: The light-sensitive tissue lining at the back of the eye. The retina converts light into electrical impulses that are sent to the brain through the optic nerve.  A detached retina can cause severe vision loss. A dilated retinal examination allows us to look for signs of an impending detachment. 
  • Iris: The colored part of the eye that regulates the amount of light entering the eye.
  • Lens: A clear part of the eye behind the iris that helps to focus light, or an image, on the retina. A cataract develops when the lens becomes cloudy or opacified.  Cataract surgery involves replacing the natrual lens with an artificial lens implant. 
  • Pupil: The opening at the center of the iris. The iris adjusts the size of the pupil and controls the amount of light that can enter the eye. A pupil defect can indicate several nearulogical conditions.
  • Cornea: The clear outer part of the eye’s focusing system located at the front of the eye. Several inherited corneal diseases can cause visual blur and distortion, as well as a dry cornea. 

How Your Eyes Work

Vision begins when light rays are reflected off an object and enter the eyes through the cornea, the transparent outer covering of the eye. The cornea bends or refracts the rays that pass through a round hole called the pupil. The iris, or colored portion of the eye that surrounds the pupil, opens and closes (making the pupil bigger or smaller) to regulate the amount of light passing through. The light rays then pass through the lens, which actually changes shape so it can further bend the rays and focus them on the retina at the back of the eye. The retina is a thin layer of tissue at the back of the eye that contains millions of tiny light-sensing nerve cells called rods and cones, which are named for their distinct shapes. Cones are concentrated in the center of the retina, in an area called the macula. In bright light conditions, cones provide clear, sharp central vision and detect colors and fine details. Rods are located outside the macula and extend all the way to the outer edge of the retina. They provide peripheral or side vision. Rods also allow the eyes to detect motion and help us see in dim light and at night. These cells in the retina convert the light into electrical impulses. The optic nerve sends these impulses to the brain where an image is produced.

Cones are concentrated in the center of the retina in an area called the macula, and provide clear, sharp central vision and detect colors and fine details. Rods are located outside the perimeter of the macula and extend all the way to the outer edge of the retina. They provide peripheral vision, allow the eye to detect motion, and help us see in dim light and at night.

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Children with uncorrected vision conditions or eye health problems face many barriers in life … academically … socially … and athletically. High-quality eye care can break down these barriers and help enable your children to reach their highest potential.

Vision doesn't just happen. A child's brain learns how to use eyes to see, just like it learns how to use legs to walk or a mouth to form words. The longer a vision problem goes undiagnosed and untreated, the more a child's brain learns to accommodate the vision problem.

That's why a comprehensive eye examination from Kaster Eye Clinic of Green is so important for children. Early detection and treatment provide the very best opportunity to correct vision problems, so your child can learn to see clearly.

Eighty percent of all learning is performed through vision. Make sure your child has the best possible tools to learn successfully.

More Info:
AllAboutVision.com – Children’s Vision

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Many optometrists, such as at Kaster Eye Clinic, are expanding their traditional roles to include other areas that affect eye health, such as nutrition. Research has shown that nutrition can impact the development of cataracts and age-related macular degeneration (AMD), which are the two leading causes of blindness and visual impairment among millions of aging Americans. Nutrition may be particularly important given that currently, treatment options after diagnosis for these eye diseases are limited.

 

Information courtesy of the American Optometric Association, 3/14/11

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Whether you already wear contact lenses or are considering them, this section serves as a primer. Facts and statistics about contact lens wearers, pointers for safe and successful use of contact lenses, and contact lenses and cosmetics are just a few of the topics covered here.

Getting started right with your contact lenses involves going to an eye doctor who provides full-service care, such as Kaster Eye Clinic of Green. This includes a thorough eye examination, an evaluation of your suitability for contact lens wear, the lenses, necessary lens care kits, individual instructions for wear and care and unlimited follow-up visits over a specified time.

 

Information courtesy of the American Optometric Association, 3/14/11

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Recommended Examination Frequency For the Pediatric Patient

Patient Age
Examination Interval
 
Asymptomatic/Risk Free
At Risk
Birth to 24 Months At 6 months of age By 6 months of age or as recommended
2 to 5 years At 3 years of age At 3 years of age or as recommended
6 to 18 years Before first grade and every two years thereafter Annually or as recommended

Children considered to be at risk for the development of eye and vision problems may need additional testing or more frequent re-evaluation. Factors placing an infant or child at significant risk for visual impairment include:

  • Prematurity, low birth weight, oxygen at birth, grade III or IV intraventricular hemorrhage
  • Family history of retinoblastoma, congenital cataracts, or metabolic or genetic disease
  • Infection of mother during pregnancy (e.g., rubella, toxoplasmosis, venereal disease, herpes, cytomegalovirus, or AIDS)
  • Difficult or assisted labor, which may be associated with fetal distress or low Apgar scores
  • High refractive error
  • Strabismus
  • Anisometropia
  • Known or suspected central nervous system dysfunction evidenced by developmental delay, cerebral palsy, dysmorphic features, seizures, or hydrocephalus

Recommended Examination Frequency For the Adult Patient

Patient Age
Examination Interval
 
Asymptomatic/Risk Free
At Risk
18 to 60 years Every two years Every one to two years or as recommended
61 and older Annually Annually or as recommended

Patients at risk include those:

 

Information courtesy of the American Optometric Association, 3/14/11

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