Proper eyecare can prevent many eye conditions and early detection can protect your vision. We continually advise our patient's on topics related to eyecare and treament of eye disorders through office newsletters, free brochures and literature, private lectures for local clubs and organizations, and complimentary community seminars and eye screenings.
 
For definitions of eye terminology click the links below:


 

Anatomy of the Eye:
Cornea
Pupil
Lens
Iris
Vitreous
Retina
Optic Nerve
Sclera
Macula
Understanding Your Prescription

Focusing Problems:
Nearsightedness
Farsightedness
Astigmatism
Aging

 Eye Conditions:
Allergies
Amblyopia(Lazy Eye)
Blepharitis
Cataracts/Cataract Surgery
Conjunctivitis (Pink eye)
Corneal Infections
Diabetic Retinopathy
Dry Eyes
Floaters and Flashes
Glaucoma
Keratoconus
Macular Degeneration
Pterygium
Ptosis(Lid Droop)
Retinal Detachments
Strabismus (Eye Turns)
 
 
 
Anatomy of the Eye
 
 
Cornea - The cornea provides most of the focusing power when light enters the eye. The cornea is composed of five layers of tissue. The outer layer (epithelium) is the eye's protective layer. This layer is made of regenerative cells that have the ability to grow back within 3 days, and therefore, allow for fast healing of superficial injuries. Most of the inner layers provide strength to the eye. It is the cornea, which is sculpted in both PRK and LASIK.

Pupil - The pupil is the ‘black circle' in your eyes. The primary function of the pupil is to control the amount of light entering your eye. When you are in a bright environment, the pupil becomes smaller to allow less light to pass through. When it is dark, the pupil expands to allow more light to reach the back of your eye.

Lens - The lens is the clear structure located behind the pupil. Its primary function is to provide fine-tuning for focusing and reading. The lens performs this function by altering its shape. At about the age of 40-50, the lens becomes less flexible and presbyopia sets in. At about the age of 60-70, the lens gradually becomes cloudy and hard (cataract formation), preventing light from entering the eye.

Iris - This is the colored part you see in people's eyes (i.e. blue/green/brown/hazel). The primary function of the iris is to control the size of the pupil through the contraction and expansion of the muscles of the iris.

Vitreous - This is the clear ‘gel-like' substance located inside the eye's cavity. It provides the spherical shape to your eye. The vitreous may develop small clumps or ‘floaters', which are more common in nearsighted people.

Retina - The retina consists of fine nerve tissue that lines the inside wall of the eye and acts like the film in a camera. Its primary function is to capture and transmit images to the brain via the optic nerve.

Optic Nerve - The optic nerve carries images from the retina to the brain.

Sclera - This is the ‘white part' that we see in people's eyes. The sclera's purpose is to provide structure, strength, and protection for your eye.

Macula - The small sensitive area of the retina that gives central vision; it contains the fovea which is at the center of the macula area. When you fixate or look directly at an object it is viewed with the fovea.
 
 
Understanding Your Prescription
Visual refractive disorders of the eye (e.g. myopia, hyperopia, astigmatism and presbyopia) are measured in units called ‘diopters’. Diopters represent the amount of correction needed in corrective lenses to normalize your vision. The more nearsighted or farsighted you are, the higher your prescription in diopters.

Your Prescription is written in three numbers: For example, -5.00 –1.50 X 180 represents a typical prescription.

• The first number (-5.00) identifies your degree of nearsightedness or farsightedness. The sign identifies whether you are nearsighted (-sign) or farsighted (+ sign).
• The second number (-1.50) identifies your degree of astigmatism, if you do in fact have any. The number can be written either with a + sign or a – sign.
• The third number (1800 is the axis, which indicates the direction of your astigmatism. An axis of 180 degrees, for example, means the astigmatism is horizontal. Therefore, -5.00 –1.50 X 180 means that the patient is moderately nearsighted, with a moderate degree of astigmatism in a horizontal direction.
 
 
Focusing Problems

Myopia (Nearsightedness) -
More than 70 million people in North America are nearsighted. Myopia occurs when an eye is too long for the cornea's curvature. Light rays entering the eye do not come to a sharp focus on the retina at the back of the eye. Instead, they focus further forward, producing a blurred image.

The term ‘nearsighted' means that you can see ‘near' objects clearly without glasses, but objects further in the distance are blurry. There are varying degrees of myopia or nearsightedness. The more myopic you are, the more blurred objects appear in the distance, the higher your eyeglass prescription and the thicker your glasses.

Of all myopic people, about 90% have corrections less than –6.00 diopters. The table below shows the categories of severity for myopia.

• Mild Myopia < -3.00 dioptersModerate
• Myopia – 3.00 to –6.00 diopters
• Severe Myopia –6.00 to –9.00 diopters
• Extreme Myopia > -9.00 diopters

Hyperopia (Farsightedness) -
Hyperopia occurs when an eye is too short in relation to the cornea's curvature. Light rays entering the eye focus behind the retina, producing a blurred image.

Farsighted individuals, however, can use their focusing muscles to ‘pull' the image forward onto to the retina, unlike a nearsighted person. In a young person with severe hyperopia, or once presbypopia sets in around age 40-45. distant objects are seen more clearly than near objects and one may need reading glasses or bifocals.

Astigmatism -
Many patients with myopia have some degree of astigmatism, or ovalness to their cornea. It is the most refractive condition, and occurs to some extent in most eyes. Astigmatism occurs when the cornea is shaped more like a football or egg, rather than round like a basketball. As a result, patients with astigmatism experience distortion or tilting of images because of the unequal bending of light rays entering the eye. Patients with high degrees of astigmatism have blurred vision not only for distance objects, as with myopia, but for near objects as well.

Astigmatism is also measured in diopters. Of all myopic people, 50% or more have astigmatism as well. Most of these people have corrections of less than 1 diopters. The table below shows the categories of severity for astigmatism.

• Mild Astigmatism < 1.00 diopter
• Moderate Astigmatism 1.00 to 2.00 diopters
• Severe Astigmatism 2.00 to 3.00 diopters
• Extreme Astigmatism > 3.00 diopters
 
Presbyopia (Aging) -
Presbyopia is a normal process of aging, where the natural lens of the eye loses some of the flexibility that allows us to focus. This usually becomes more significant at an age 40-45. Everyone experiences the effect of presbyopia, some sooner, some later. Nearsighted people who become presbyopic may require bifocals in their 40's, and those who never needed glasses before will eventually require reading glasses. If you're slightly myopic, you can remove your glasses and still be able to read, even after presbyopia sets in.


After having laser correction, you will lose this ability. You will typically be normally sighted after the procedure, and you will need reading glasses for fine print to correct your presbyopia like other normally sighted person at age 40-50.

Since laser correction has no effect on your lens or your focusing muscles, it cannot be used to treat presbyopia. However another solution-Monovision- can offset this to some extent and can often help.

 
 
Eye Conditions

Allergies - An allergy is a reaction of the body's immune system to a foreign substance (example: pollen, animal dander, etc) When the eyes are affected, the most common symptoms are redness, itching, tearing, swollen eyelids, and stickiness.
 
Amblyopia(Lazy Eye) - Amblyopia, also known as "lazy eye," is reduced vision – uncorrectable with lenses – in an eye that has not received adequate use during early childhood.  Amblyopia has many causes. Most often it results from either a misalignment of a child's eyes, such as crossed eyes (strabismus), or a difference in image quality between the two eyes (one eye focusing better than the other, also known as anisometropia). In both cases, one eye becomes stronger, suppressing the image of the other eye. If this condition is not treated in early childhood, the weaker eye may become permanently impaired. With early diagnosis, amplyopia can be treated and loss of vision prevented.

 
Blepharitis - Blepharitis is an inflammation of the eyelids. The membrane covering the inside of the eyelid and the white of the eye may also become inflamed. Blepharitis can be caused by bacteria on the eyelids or on the skin around the eyes. Dandruff or oily skin can also cause blepharitis. Wearing contact lenses or makeup can make the symptoms worse. Blepharitis can't always be cured, but it can be controlled.
   

Cataracts/Cataract Surgery - A cataract is a clouding of the lens of the eye. The analogy of a peach can be used to describe these layers. The nucleus or center of the lens is the pit of the peach, the cortex is the flesh surrounding the pit, and the capsule or elastic covering is the skin of the peach. The lens is supported inside the eye by tiny ligaments (zonules) that support the lens capsule.
In a young person, the lens is crystal clear and allows light to pass through and focus on the retina. As the lens ages, the nucleus turns yellow and loses its ability to accommodate (focus for close work) although the lens usually remains clear. As the lens continues aging, the nucleus turns from yellow to amber and ultimately to brown. Aging changes do not necessarily result in a cataract unless the nucleus becomes opaque, or opacities that block or scatter light develop in the cortex or under the capsule.
   

Conjunctivitis (Pink eye) - Conjunctivitis is an inflammation of the lining of the eyelid and the transparent tissue covering the white part of the eye.

Corneal Infections - Sometimes the cornea is damaged after a foreign object has penetrated the tissue, such as from a poke in the eye. At other times, bacteria or fungi from contaminated contact lens can pass into the cornea. Situations like these can cause painful inflammation and corneal infections called keratitis. These infections can reduce visual clarity, produce corneal discharge, and erode the cornea leading to a corneal ulcer. Corneal infections can also lead to corneal scarring, which can impair vision and may require a corneal transplant. As a general rule, the deeper the corneal infection, the more severe the symptoms and complications. It should be noted that corneal infections, although relatively infrequent, are the most serious complication of contact lens wear. Minor corneal infections are commonly treated with antibiotic eye drops. If the problem is severe, it may require more intensive antibiotic or anti-fungal treatment to eliminate the source of the infection, as well as steroids eye drops to reduce inflammation. Frequent visits to an your eye doctor may be necessary for several months to eliminate the problem.
 
Diabetic Retinopathy - If you have diabetes mellitus, your body does not use and store sugar properly. High blood-sugar levels can damage blood vessels in the retina, the nerve layer at the back of the eye that senses light and helps to send images to the brain. The damage to retinal vessels is referred to as diabetic retinopathy. The best treatment is to prevent the development of retinopathy as much as possible. Strict control of your blood sugar will significantly reduce the long-term risk of vision loss from diabetic retinopathy.
   
Dry Eyes - Dry eyes occur when there is a lack of lubricating tears over the surface of the eye causing a stinging, burning or scratchy sensation. Some common causes of dry eye include aging, heaters and air conditioners, wind, smoke or dry weather, allergies, medications, and eyelid problems such as injuries to the eye or diseases like rheumatoid arthritis. Artificial tears are the most common treatment for dry eyes. If they don't relieve your symptoms, your eye doctor may put in plugs or do surgery to stop the draining and increase the tear film.

Floaters and Flashes - Floaters are tiny clumps of gel or cells inside the vitreous, the clear jelly-like fluid that fills the inside of your eye. While these objects look like they are in front of your eye, they are actually floating inside, and you will see small specks or clouds moving in your field of vision. Flashes are caused when the vitreous gel rubs or pulls on the retina. You may see what look like flashing lights or lightning streaks, and you may have experienced this same sensation if you have ever been hit in the eye and seen “stars”. While flashes and floaters are relatively common, you should still see your eye doctor right away if one new floater appears suddenly, or if you see sudden flashes of light.
   
Glaucoma - Glaucoma encompasses a group of diseases that can damage the eye's optic nerve and lead to vision loss, even blindness. Many treatments, including medication and surgery, can help glaucoma patients.
 
Keratoconus - Keratoconus is an uncommon condition in which the cornea (the clear front window of the eye) becomes thin and protrudes. Keratoconus literally means a cone shaped cornea. This abnormal shape can cause serious distortion of vision.
   
Macular Degeneration - Macular degeneration is a condition that damages the macula, the central part of the retina. The macula is responsible for central vision and the ability to see detail. When the macula is damaged, the eye loses its ability to see detail, such as small print, facial features or small objects. The damaged parts of the macula often cause scotomas, or localized areas of vision loss. When you look at things with the damaged area, objects may seem to fade or disappear. Straight lines or edges may appear wavy.

Pterygium - A pterygium is a fleshy groth that invades the cornea (the clear front window of the eye). It is an abnormal process in which the conjunctiva (a membrane that covers the white of the eye) grows into the cornea. Pterygium occur more often in people who spend a great deal of time outdoors, especially in sunny climates. When a pterygium becomes red and irritated, topical eyedrops or ointments may be used to help reduce the inflammation. If the pterygium is large enough to threaten sight, it can be removed surgically.
 
Ptosis (Lid Droop) - Ptosis (“toe-sis”) is a condition in which the upper eyelid droops over the eye. It is either apparent at birth or develops with age. Surgical shortening of the muscle that opens the eyelid will often lead to better vision and improved appearance.
   
Retinal Detachments - The retina is a nerve layer at the back of your eye that senses light and sends images to your brain. A retinal detachment occurs when the retina is pulled away from its normal position. The retina does not work when it is detached, and vision becomes blurred. A retinal detachment is a very serious problem that almost always causes blindness unless it is treated.
   
Strabismus (Eye Turns) - A misalignment of the eyes in which one or both may turn in, out, up or down. Strabismus is a common condition among children. It can also occur later in life. Strabismus can be treated with eyeglasses or may involve surgery to correct the unbalanced eye muscles.
   
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Gaston Eye Policies