Latest Developments in Ophthalmology

Refractive surgery has brought a revolution in myopia, hyperopia and astigmatism correction. We are already in the third decade of laser use and we can really observe that precision and safety are already here. With the use of this impressive technology, we can forever eliminate our dependence on corrective glasses or contact lenses.

 

There are two methods of effective correction of high or low degrees of myopia, hyperopia and astigmatism: PRK and LASIK (conventional LASIK, where the creation of the flap is done with a mechanical microkeratome and FEMTO-LASIK, where it is done with a femtosecond laser). The difference between these two methods lies in the fact that, in the first, the correction occurs on the surface of the cornea, while in the second in its interior. In PRK there is some minor discomfort the first 2-3 days, while in LASIK the discomfort is insignificant and eyesight restoration happens almost immediately, on the very first day. The final result is the same in both cases. An important role in the patient's decision to do away with glasses and contact lenses plays the trust and relationship between doctor and patient. The most important part of a refractive surgery is thorough preoperative tests, which will show us if the patient is eligible for a procedure in that particular area. Detailed and thorough preoperative tests ensure the success of the procedure. Timewise, the procedure lasts only a few minutes and it is never longer than 5 or 6 minutes for both eyes. The doctor uses local anesthesia and the patient feels no pain. It is important to note that the correction is permanent and in the very few cases where some degrees of the condition remain, then an additional laser procedure can be done to achieve full correction. An important role in the patient's decision to do away with glasses and contact lenses has the trust and relationship between doctor and patient. The 25 years of laser use allow us to say that the possibility of serious complications is negligible. Even those rare complications can be treated. We are in a position to say with absolute certainty that the chances of infection from contact lenses are more than the possible complications of refractive surgery.

Keratoconus is a non-inflammatory disorder of the cornea, which is characterized by the presence of a progressive deformation of its surface. The cornea gradually takes a “conical” shape (it expands by creating an extrusion), deforming the reflection formed in the fundus of the eye. A progressive thinning can also be observed, as well as scarring, and finally opacity in the area where the cone has formed. Despite ongoing research, the causes of keratoconus are essentially unknown. It is generally considered a genetic disease caused by multiple factors, mainly irregularities in the structure or the metabolism of various segments of the cornea. It used to be considered a rare disorder, perhaps because there weren't any diagnostic means to detect it in the early stages. Today we know that keratoconus is not so rare. There are more than 20,000 people in Greece with keratoconus (approximately 1 for every 2,000 people). It usually appears in adolescence and progresses relatively fast, while later the rhythm of deterioration decreases and stops at around 35 years of age. Physical examination does not always provide evidence for a positive diagnosis. However, keratometry can give altered parameters. The patient presents an irregular progressive astigmatism that previously did not exist. In more advanced stages, the diagnosis is easier and with the help of a slit lamp, the cornea can present the known conical form, as well as thinning and haze of its central area. Nonetheless, positive diagnosis occurs with the help of an electronic device and a test called “corneal map” (corneal topography). In this test, a 2D image of the corneal topography is taken and, based on that, we can diagnose even the subclinical forms (those that haven't presented any symptoms). It is strongly believed today that the riboflavin method can substantially delay or even stop the development of keratoconus, saving the patient from a potential corneal transplant. This method is still evolving and is called C3-R (Corneal Collagen Crosslinking with Riboflavin). Through lab tests and clinical examinations, it has been proven that it reinforces the inner structure of the cornea, stabilizing its architecture and, specifically, strengthening the bonds of the corneal collagen fibers, which are one of the basic ingredients for maintaining its structure.

C3-R treatment can be done at the clinic and lasts about 60 minutes. During the treatment, drops of a riboflavin (B2) mix are instilled, which are then activated with UV rays.

Cataract is a haze of the natural lens inside the eye. This lens, which is found behind the iris (the colored part of the eye) is capable of moving and changing shape, so that it can function exactly like the lens of a camera, by focusing bright images on the retina, which, in turn, sends them to your brain. The human lens, consisted mainly of protein and water, can present some haze, in such a degree that the light and images are not allowed to reach the retina. Eye damage, certain disorders or even some medicine can cause this haze. In more than 90% of the cases, however, this haze is cause by the aging process. Cataract isn't a deposition in the eye and cannot be removed with diet or laser. The best way to treat cataract is to remove the old, hazy lens and to replace it with an artificial one. Cataract can be the cause of the blurring of clear images, the dimming of bright colors or a decrease in vision at night. It is also possible that it is the reason why reading or bifocal glasses that used to help you read or perform simple tasks, cannot help you any longer. Unfortunately, it is not feasible to prevent cataract, but only to remove and replace it with an artificial lens which can restore your vision and significantly improve quality of life. The proper time to remove cataract is when the quality of your vision starts causing restrictions in your activities and your enjoyment of life.

Glaucoma is a group of ocular disorders that share as a symptom the destruction of the optic nerve. The optic nerve consists of nerve fibers and is responsible for the transfer of images from the eye to the brain. Glaucoma is a disorder that leads to loss of vision without warning. It is possible that there are no symptoms in the early stages of the disease and that patients with glaucoma don't know they have it. Loss of vision starts with peripheral or side vision. This loss might be compensated by the unconscious turn of the head towards the corresponding side, which results in the patient not realizing his condition until there is a significant loss of visual acuity.

For this reason, early diagnosis is important and can prevent major damage. All people above forty years of age and especially those with a family history of glaucoma should be examined once or twice a year.

Diabetic Retinopathy is a disorder at the small (capillary) vessels of the retina. Diabetic retinopathy concerns every diabetic patient either insulin dependent (Type 1) and of young age or non-insulin-dependent (Type 2) and the disease has appeared later in life. The diabetic patient should know that the most important thing he needs to do for his condition is to keep his blood sugar under control. Blood sugar not under control causes a more rapid progress of diabetic retinopathy. He should also control his hypertension, his hyperlipidemia (cholesterol and triglycerides), if such exists, and limit smoking and alcohol. Patients with diabetes should be examined by an ophthalmologist once every 6 months. It is important to know that today, with the improved methods of diagnosis and treatment, only a small percentage of patients develop retinopathy and face serious eyesight problems.

Age-related macular degeneration, is the most common cause of irreversible blindness in the western world. This disorder affects the central area of the fundus, which is also the most important. The consequence? A gradual deterioration of our central vision with no other symptoms. Several studies have calculated that 6% to 10% of people among the ages of 65 and 74 years old and 19% to 30% of people above 75 years old have this disorder. As we can see, it is related to the elderly and for this reason it is called age-related macular degeneration. Age-related macular degeneration is caused by many factors. These risk factors may include age, heredity, light-colored irises, smoking, cardiovascular diseases, as well as sunlight. The most important factor is, of course, the aging process.

 

What can we do to prevent it?

Wear sunglasses with UV filter, to protect our eyes.

You can take dietary supplements, multivitamins and zinc products. Even though it is difficult to prove those products' preventive action, several studies have shown that they can help delay the disease. Dosage should be indicated by the ophthalmologist in cooperation with the pathologist, in case of contraindications.

You should regularly check your eyes after 40 years of age and visit your ophthalmologist as soon as you observe changes in your eyesight, especially scotomas related to your central vision. Special diagnostic tests like OCT and Fluoroangiography are quite often valuable in the treatment of the disease.

You should reduce or, better yet, quit smoking.

Regulate your blood pressure, your cholesterol and consult with a cardiologist, in case it is needed.

 

 

 

Published in the magazine Dimosios Tomeas, volume 286, July-August 2011

 

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