Refractive Errors of Eye: Types and Treatment

The eye is like a camera in which the light passes through a lens system back onto the film. The cornea and lens are at the front of the eye (anterior chamber) and are similar to a camera's lens system. The retina is located at the back of the eye (posterior chamber) and is similar to the camera's film. In the normal eye, light rays of an image pass through the cornea and the lens and are focussed directly on the retina to produce a clear image.

A refractive error, is an error in the focusing of light by the eye and a frequent reason for reduced visual acuity (VA). Visual Acuity (VA) can be defined as "acuteness or clearness of vision, especially form vision, which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain."

Refractive Errors of Eye can be classified as Spherical Errors and Cylindrical Errors.

Spherical Errors: These type of errors are caused when the optical power of eye is either too small or too large to focus light on retina of eye, resulting in a blurry vision. These can be further split into two cases: Nearsightedness (Myopia) and Farsightedness (Hyperopia).

In Myopia (or nearsightedness), the light rays are passed through the cornea and lens but the point at which they converge (focus) is in front of the retina, not on the retina. This configuration allows clear images of near objects but not those that are far away.

 Whereas in Hyperopia, the light rays do not converge or focus by the time they reach the retina. Hyperopic patients can focus on more distant objects, but not images that are close at hand.

Cylindrical Errors: Cylindrical errors occur when the optical power of the eye is too powerful or too weak across one meridian. It is as if the overall lens tends towards a cylindrical shape along that meridian. The angle along which the cylinder is placed is known as the axis of the cylinder, while 90 degrees away from the axis is known as the meridian of the cylinder.

People with a simple astigmatic refractive error see contours of a particular orientation as blurred, but see contours with orientations at right angles as clear. A person with cylindrical error is said to have Astigmatism.

The other type of Refractive Error is Presbyopia. Presbyopia describes the condition where the eye exhibits a progressively diminished ability to focus on near objects with age. Although exact mechanisms are not known with certainty, however, the research evidence most strongly supports a loss of elasticity of the crystalline lens, although changes in the lens's curvature from continual growth and loss of power of the ciliary muscles (the muscles that bend and straighten the lens) have also been postulated as its cause.

Treatment of Refractive Errors:

How refractive errors are treated or managed depends upon the amount and severity of the condition. Those who possess mild amounts of refractive error may elect to leave the condition uncorrected, particular if the patient is asymptomatic. For those who are symptomatic, glasses, contact lenses, refractive surgery, or a combination of the three are typically used. For more information, visit accuratesight.com

Surgical treatment options include clear lens extraction, LASIK eye surgery, phakic IOL and Radial Keratotomy.

As Presobyia,is a natural part of the human aging process, presbyopia is not routinely curable.Treatment for presbyopia has advanced significantly in recent years, thanks in no small part to the ready availability of inexpensive over-the-counter reading glasses with corrective lenses that cover a wide gamut of magnification levels. Contact lenses have also been used to correct the focusing loss that comes along with presbyopia. Some people choose to correct the focus problems with bifocals, giving them a wider range of vision without having to use a second set of glasses. ew surgical procedures may also provide solutions for those who do not want to wear glasses or contacts, including the implantation of accommodative intraocular lenses (IOLs).

Eye Cataract: Causes,Detection and Treatment

A cataract is a cloudiness of the eye's natural lens, which lies between the front and back areas of the eye.Vision through a 'cloudy' less transparent lens is blurry and is quite like looking through a misty glass or looking from behind a 'waterfall'. No one knows for sure why the eye's lens changes as we age, forming cataracts. Researchers are gradually identifying factors that may cause cataracts — and information that may help to prevent them.

Many studies suggest that exposure to ultraviolet light is associated with cataract development, so eye care practitioners recommend wearing UV sunglasses and a wide-brimmed hat to lessen your exposure. Other studies suggest people with diabetes are at risk for developing a cataract. The same goes for users of steroids, diuretics and major tranquilizers, but more studies are needed to distinguish the effect of the disease from the consequences of the drugs themselves. Some believe that a diet high in antioxidants, such as beta-carotene (vitamin A), selenium and vitamins C and E, may forestall cataract development. Meanwhile, eating a lot of salt may increase your risk.

Other risk factors may include cigarette smoke, air pollution and heavy alcohol consumption. A small study published in 2002 found lead exposure to be a risk factor; another study in December 2004, of 795 men age 60 and older, came to a similar conclusion. But larger studies are needed to confirm whether lead can definitely put you at risk, and if so, whether the risk is from a one-time dose at a particular time in life or from chronic exposure over years. If a person develops Cataract only treatment for Cataract is Cataract Surgery.The modern techniques do not require the cataract to mature & ripen for the decision of surgery. Whenever, the eye cataract happens to interfere with your lifestyle that would be the time when the surgery should be planned out. By lifestyle is meant when you feel that you are having problem or difficulty in carrying out your personal & professional visual needs to your requirements that should be the time when surgery should be opted for. For example, if you are unable to drive safely because of cataract formation it would be wise to have them removed. Some patients may need cataracts removed for medical reasons; for example, if a patient is diabetic and the cataract is interfering with the ophthalmologist's examination of the retina, then it may be recommended to the patient to have the cataract removed.

To remove Cataract a small incision is made into the eye. Dr. Rohit Om Parkash uses an ultrasound machine {INFINITI VISION SYSTEM} wherein torsional emulsification is used to break it up, and then remove it. The back membrane of the lens (called the posterior capsule) is left in place. Usually, a replacement lens called an Intra Ocular Lens is used.

Symptoms of Eye Cataract?

A cataract starts out small, and at first has little effect on your vision. You may notice that your vision is blurred a little, like looking through a cloudy piece of glass. Colors may not appear as bright as they once did

The most common symptoms of a cataract eye are:

Cloudy or blurry vision. Problems with light, such as headlights that seem too bright, glare from lamps or very bright sunlight. Colors that seem faded. Poor night vision. Double or multiple vision.

If you notice any of the symptoms described previously, go to have an eye exam. By performing it, the Ophthalmologist will know if you have a cataract. Your eye doctor will perform a thorough examination of your eyes. Glare testing and contrast sensitivity tests are sometimes used. There is no single objective test to determine a need for cataract surgery. The final decision for cataract surgery is made by the patient and depends on how much the decreased vision from the cataract is bothersome.

For More Information or Quick Appointment for CATARACT OPERATION, you must visit http://www.accuratesight.com.

This website is owned by Dr. Om Parkash Satyam Netralaya, the only eye institute in North India which is using the latest technology of the “TORSIONAL EMULSIFICATION” employing 2.2mm incision micro coaxial technique with IQ Intra Ocular Lens {IOL}/ RESTOR multifocal IOL implantation. This is possible because of the installation of INFINITI VISION SYSTEM, which is the most advanced Phacoemulsification unit in the world for cataract surgery. Torsional Emulsification is a much safer & efficient technique than the traditional phacoemulsification technique.

Dr. Rohit Om Parkash is the convener of the ‘THE PHOENIX PHACOSURGEONS CLUB’ which is the exclusive group of cataract surgeons in the world who have to their credit documented 30,000 phacosurgeries performed by an individual. Dr. Om Parkash Eye Institute India has completed 22 years in Refractive Surgeries. This institute was the first in the country to use for laser correction of specs, the state-of-the-art, Customized Lasik using NAVEX Quest -NIDEK CX III with Pentacam and OPD Scan. Dr. Om Parkash Eye Institute is ideally located in the most posh area of the city, 2.5 kms from bus stand, 1km from railway station and 8kms from airport.

Dr. Om Parkash Eye Institute

117-A, The Mall, Amritsar-143001

(Punjab) INDIA

Tel : +91-183-2221128, 2221132,

6531128, 6541132

Mob: +91-98158-15888

Fax: 0091-183-2220910

Lasik Eye Surgery: Before and After Lasik Eye Operation

Before laser eye surgery, an inteview is carried out to determine your personal suitability for eye surgery and to determine which type of operation may suit you and give an idea of the likely results.The next stage is to carry out a thorough eye test to determine a current up to date eye prescription and to take precise measurements of the eye structures.

It is normally recommended that you are accompanied by a friend for this examination as part of procedure involves using eye drops which dilate your pupil and blur your vision for upto 18 hours. Also it is advised to carry a pair of sunglasses on this day,as bright lights and dilated pupils can cause discomfort. If you normally wear contact lenses these can affect the corneal curvature and consequently it is necessary if you wear soft lenses to discontinue wear for at least one week prior to,and on the day of consultation,and with hard and gas permeable lenses to discontinue wear at least four weeks prior to and on the consultation day.Normally you need to complete a general health questionaire.You are then normally given a complete eye examination. Based on the result of these examinations your eye surgeon will advise you about the most suitable procedure for you,discuss the risks and also the alternatives.You also have the opportunity to ask any further questions you may have. Visit accuratesight.com for more information and answers to your queries.

You can then decide whether or not to proceed to a surgical appointment.The advantages resulting from laser eye surgery are ability to see immediately on waking up, no more fumbling for your glasses in the dark, not having to wear glasses or contact lenses saving time and lots of money on opticians visits as well as trouble in maintenance and upkeep, improved self confidence in appearence (hopefully!), easier participation in sports leading to an overall improvement in feeling of personal well being. Most of the patients, who undergo laser eye surgery claim that they are satisfied with procedure and it has improved the quality of their life significantly and often state that they regret not having it sooner.

Lasik eye surgery is a laser surgery procedure for vision correction.The technique involves using a laser which is controlled by a computer to reshape the front surface of the eye(cornea). As with all surgery a pre-op consultation is required to ascertain the best eye surgery for the individual.In normal vision light enters the eye and is bent by the cornea and focussed to produce a sharp image on the back of the eye the retina. When a person has a refractive/visual error like short or long sight the light is bent such that a blurred image is produced.

Lasik eye surgery can be used to correct short sight, long sight and stigmatism (correct spelling astigmatism).Older patients who have presbyopia/age related near vision problems cannot have their vision improved with this procedure. The cornea has an alcohol solution applied to help lift the epithelial flap which is then cut(a fine layer about 50 microns thick ) with a Trephine blade (ALSO CAN BE CUT WITH A LASER BUT AGAIN IT IS A SIMILAR PROCEDURE ) , but not completely removed and remains hinged on one side allowing it to be replaced in the same position. The eye surgeon raises the flap, and an excimer laser shapes the the cornea to the dimensions determined at the pre op consultation.The eye surgeon replaces the epithelial corneal flap, within minutes, natural forces hold it in situ, and the eye surgery is finished.The surgery as with LASIK takes approximately 15 mins each eye. However recovery normally takes a bit longer approximately one week and there is usually some discomfort for the next 48 hours.

This is just a general outline of the what happens after laser eye surgery procedures following refractive surgery (as there are wide variations depending on individual needs and surgery techniques).Patients are normally provided with antibiotic eye medication and lubricating eye drops to be used in the days immediately after surgery. It is common and good procedure for the eye surgeon who performed your operation to exam your eyes the day immediately after any eye surgery. Further appointments are then generally advised at the desired intervals. In the first few days and hours after surgery it is important to refrain from touching or rubbing the eyes and to try and rest as much as possible and to use any medication prescribed.Protective eye shields are normally provided to prevent rubbing of eye during the night whilst sleeping.Within 3-4 days most normal day to day activities like housework,driving and shopping can be resumed. After 2-3 weeks Most sporting activities can be resumed ,however hard contact activities such as boxing,football martial arts are best left for 3 months or more to ensure the best chance of full recovery.Following the post operation laser eye surgery aftercare program advised by your eye surgeon is very important in the overall.

Dr. Ajay Khanna who heads the Refractive Surgery & Vitreo Retinal Services at Dr. Om Parkash Eye Institute India has been performing Laser correction for specs since 1997.Dr. Ajay Khanna has been the earlier ones in the country to start with Thin Flap Lasik to treat patients with high myopia & thin corneas. This eye hospital was the first in the country to use for laser correction of specs, the state-of-the-art, Customized Lasik using NAVEX Quest -NIDEK CX III with Pentacam and OPD Scan.

Dr. Om Parkash Eye Institute

117-A, The Mall, Amritsar-143001

(Punjab) INDIA

Tel : +91-183-2221128, 2221132,

6531128, 6541132

Mob: +91-98158-15888

Fax: 0091-183-2220910