A cataract is a clouding of the eye’s naturally clear lens. The form and function of the human eye can be compared to a camera with film. In order for a camera to take a clear picture the lens must be clear and the film must be functioning correctly. Just like the camera lens, if the human lens is cloudy, vision will be compromised since light and image clarity will be diminished. The lens focuses light rays on the retina, which contains light sensing cells. The retina then transmits the information to the brain to produce a sharp image of what we see. Depending on the type of cataract, when light or an image enters an eye with a cataract, the light may be filtered or scattered causing dimmed vision or glare.
The lens of the eye is near proof of the existence of a higher order. The intricate alignment, positioning and compaction of the human lens fibers beginning 25 days after conception and continuing to death is an incredible bit of evolution and/or creation, depending on your beliefs. The lens fibers are laid down in such an exact manner that the lens remains crystal clear until something interferes with its structure resulting in a cataract. As the lens grows the central fibers are more tightly compacted and will eventually become opacified or cloudy.
The structure of the human lens is like an onion. It has multiple layers, the outer covering or capsule surrounds the epithelium, cortex and central nucleus. A cataract or opacity can occur in any of these layers. Cataracts are usually characterized by your ophthalmologist or optometrist by severity (early, moderate, mature), progression (progressive, stationary) and location (anterior, posterior, cortical, nuclear).
Cataract formation is a normal process of aging but cataract development can be enhanced by various reasons including: advanced age, smoking, certain diseases, and medication especially steroids. A cataract will occur in anyone that lives old enough for the lens to begin its growth and opacification process. However, the patient should not consider cataract surgery until the cataract interferes with their lifestyle. Interestingly, the development of a cataract in a human eye has some benefits. For instance, a cataract helps to block harmful light wavelengths that have been shown to be damaging to the retina. So in way, cataracts are an evolutionary advantage. However, as a cataract progresses the benefits become a problem by blocking vision. If a patient is over 60 years of age and their eye doctor tells them they have no evidence of cataracts, the patient has either already had their cataracts removed or the doctor simply does not want to spend the time to explain the diagnosis of cataracts to the patient.
Diseases such as diabetes and collagen vascular disease and medication such as steroids can cause cataracts to progress rapidly over a short time. Smoking greatly decreases our body’s anti-oxidant capabilities and has been shown to increase cataract development. Also, direct injury from trauma or other eye surgery can precipitate cataract formation. It is usually not possible to predict exactly how quickly cataracts develop in any given person. Once the cataract has developed in an adult, improvement will not occur without surgery. No medications, dietary supplements or exercises have been shown to prevent or cure cataracts. There has been a great deal of research and discussion regarding the role that diet and nutrition plays in cataract development. However, researchers have yet to show any clear benefit in diet or nutrition in preventing cataract formation. Wearing sunglasses with UV protection may help slow progression. The research is continuing.
The word cataract is defined in the dictionary as a waterfall, rapid or deluge. In a waterfall or rapid, every obstacle or irregularity in the path of the water cascade will affect how the water continues to flow downstream. This will determine whether the journey will be turbulent or silky smooth. Like a river rapid, successful cataract surgery begins with the initial patient appointment where the history is documented and ends when the patient receives their post–operative instructions.
Surgery is the only way a cataract can be removed. However, if the symptoms of cataracts are not bothering the patient, surgery may not be needed. Sometimes a simple change in your eyeglass prescription may be helpful. When you are no longer able to see well enough to perform your activities of daily living such as reading, cooking, shopping, engaging in recreational activities, taking medication and or driving, it’s time to consider cataract surgery. It is not true that cataracts need to be “ripe” before they can be removed or that they need to be removed just because they are present. Based on your individual lifestyle and symptoms, you and your ophthalmologist should decide together when surgery is appropriate. The initial examination for cataracts most commonly includes a complete dilated eye examination by your ophthalmologist or optometrist.
Cataracts have become an increasingly common cause of decreased vision as our population ages. In the United States, cataracts are the leading cause of vision loss among people over 55. This is a result of the changing demographics of our population. In 2006, over 80 million “baby boomers” began turning 60 years of age. Fortunately cataracts are treatable.
Because of our changing population and also due to the advances in technology, cataract surgery with lens implantation has become one of the most frequently performed as well as one of the safest and effective types of surgery available in the United States. It has been estimated that over 3 million cataract operations are being performed annually and more than 95% of those surgeries are performed with no complications.
The journey downstream to an uncomplicated cataract surgery begins with the first visit to your ophthalmologist or optometrist. The single most important choice one will need to make is in the selection of an ophthalmologist or cataract surgeon. If family, friend, family physician or optometrist recommends the surgeon, the patient should be scheduled to see the surgeon for an initial consultation prior to surgery. A physician/patient rapport should be established prior to surgery. The patient should feel comfortable speaking with the surgeon and should not hesitate to ask any question or express any concerns to the surgeon. The patient should be given the opportunity to meet his or her surgeon well prior to the day of surgery, not the same day. This will allow the patient adequate time to research the surgeon’s background, including board certification, credentials and malpractice sanctions. Patients should never be pressured into having surgery. Cataract surgery is an “elective” procedure. Emergent cataract surgery is rarely needed. The surgeon should be accessible, preferably local and available 24/7, if any issues arise. A good cataract surgeon will show compassion, patience, and treat every patient as an individual, each with unique needs and expectations. Only after this rapport has been established should cataract surgery be considered, since only then can informed consent for surgery be obtained. The risks, benefits, and options to cataract surgery should be explained and many offices will have written information for review at home. Even though the success rate of uncomplicated cataract surgery is greater than 95% no surgeon can guarantee success. Some of the risks of cataract surgery can include infection, hemorrhage, loss of vision, and the need for other surgeries. The benefit would be to improve the vision or diminish the amount of glare. The options to cataract surgery are simply surgery now, later or never. A dedicated cataract surgeon would be happy to explain the surgery and his or her technique to the patient. The patient should ask where the surgery is performed and be given the opportunity to visit the facility. The choice of lens implant is also important and may determine the level of need for eyeglasses after the surgery.
After the cataract or lens of the eye is removed during surgery, the lens is replaced with an artificial lens implant. The technology of lens implants has improved dramatically over the last 20 years. Early implants were rigid and required larger incisions. Today, lens implants can be folded and injected through much smaller incisions. Also, new generation lenses help protect the eye from potentially damaging light wavelengths. Traditional cataract lens implants would help improve distance vision only. However, if any significant degree of astigmatism were present the patient would need glasses to achieve the sharpest distance vision. Also, many patients are candidates for a premium multifocal lens implant. Today with the advent of custom refractive cataract surgery, multifocal lens implants are available. For example, the ReSTOR®, ReZoom™ or Cystalens® implants can improve both distance and near vision to help patients minimize or possibly eliminate the need for eyeglasses and the AcrySof® Toric lens corrects for certain degrees of astigmatism.
Cataract surgery has undergone revolutionary changes over the last two decades, with the most truly amazing advances in technique and technology occurring in the last 15-20 years. In addition to the high tech lens implants previously described, modern Cataract surgery has evolved from a one to two hour in-patient procedure where the patient would be admitted to the hospital for at least 3 days and placed with sand bags around the head to a 10 to 20 minute out- patient procedure where the patient goes home after surgery and may ultimately not need eyeglasses for distance or near vision. Some of the advances in technique include the use of topical anesthesia, small no-stitch incisions and the development and refinement of high tech machines that emulsify the cataract using phacoemulsification or ultrasound. The initial cataract incision twenty years ago was 10-12 millimeters in length. The large incision increased the risk of infection, leakage and could induce a large degree of astigmatism. Prior to the current use of phacoemulsification whereby the cataract is gently emulsified and removed, the lens was simply pushed out of the eye in one piece through the large incision. This technique is still widely used in other countries and rarely performed during certain circumstances in the United States. The development of small incision, clear corneal incisions and operative times of 10-20 minutes allowed cataract surgery to be performed under topical anesthesia with the patient awake. Cataract surgery under topical anesthesia is performed using mild sedation and topical numbing drops. In general it is not necessary for the cataract surgeon to use injections or needles to anesthetize your eye. However, in some patients such as children, those with claustrophobia, anxiety, Alzheimer’s or other mental limitations alternative anesthetic options should be discussed.
Recently, Femtosecond laser-assisted cataract surgery has been approved in the United States. This technology incorporates laser similar to that used in Lasik eye surgery. The laser is able to construct very precise incisions and is able to break-up the cataract prior to removal with phacoemulsification. The laser can also treat certain degrees of astigmatism. Laser-assisted cataract surgery will most likely be the preferred method in years to come.
Modern “state of the art” refractive micro-incision cataract surgery has evolved into an efficient streamlined surgery where every step requires successful completion prior to performing subsequent steps.
The expertise and experience of the surgeon you chose is vital in providing for the best visual correction and outcome.
Edward V. Hernandez, MD is owner and president of Eyes of The Southwest. He has practiced Ophthalmology in Las Cruces for over 15 years. He graduated summa cum laude from the University of California, Irvine and received his MD degree from the prestigious University of California, San Francisco Medical School. He then went on and completed his Ophthalmology residency at the University of California, Davis. He has published a number of scientific journal articles in the electrophysiology of the retina and holds a patent on a medical device under development.