Cataract and Treatment
Cataract surgery has undergone an amazing transformation over the past several years. New advances in technology, mathematics and new materials have greatly enhanced cataract surgery.
What is a Cataract
A cataract is a clouding (opacity) of the lens of the eye that causes a progressive, painless loss of vision.
Cataracts are the leading cause of blindness worldwide. Cataracts are common in the United States, where they affect mostly older adults. Almost one in five people between the ages of 65 and 74 develop cataracts severe enough to reduce vision, and almost one in two people older than 75 have them. Fortunately, people in the United States can often get their cataracts treated before they cause blindness. Cataracts usually develop without any apparent cause, however, they can result from injury to the eye, prolonged exposure to certain drugs (such as corticosteroids) or to x-rays (such as with radiation therapy to the eye), inflammatory and infectious eye diseases, and as a complication of diseases such as diabetes.
Cataract surgery today is safe, effective and quite common. In fact, if you have been told that you have a cataract, you are definitely not alone. Each year in the United States, more than 2.5 million people have cataract surgery.
Thanks to advanced surgical procedures and lens implant technology, cataract is one of the safest and most successful surgical procedures that you can have. Cataract surgery is performed on an outpatient basis and usually only requires a few hours of your time from beginning to end.
How is Cataract Surgery Performed
Cataract surgery today is quite comfortable. First, the procedure will begin with your eye being treated with an anesthetic so that you will feel little if anything during your surgery.
Your eye surgeon operates while looking through a highly specialized microscope, designed exclusively for this purpose. A very small, beveled incision, less than 1/8 of an inch, is made at the edge of the “clear cornea”. The clear cornea is the transparent covering of the front of the eye.
The incision is just large enough to allow a microsurgical, ultrasonic, oscillating probe the size of a pen tip to be inserted. This instrument gently fragments the cloudy lens, using high frequency sound waves. The gently fractured cataract pieces are small enough to be washed away, drawn through the instrument and removed from the eye. This process is called “phacoemulsification”. The posterior capsule, an elastic bag-like membrane that held the lens, is left in place.
The incision is commonly called “self-sealing” because the eye’s natural internal pressure holds the incision tightly closed allowing the eye to heal without stitches. The chances of developing astigmatism (distorted vision) after surgery are significantly decreased by eliminating stitches, which tend to pull the eye’s surface slightly out of its natural shape.
Once all the small fractured bits of the cataract have been removed, a tiny new clear implant lens is folded, inserted through the small incision, and allowed to open up inside the posterior capsule.
The surgery typically takes 10-20 minutes, and is performed on an outpatient basis. This means that you will have the surgery and then go home, usually around 30 minutes afterwards. Most of the time only local anesthesia is used, so you will be awake for the entire process. After the surgery, you are taken to the recovery room and then released. You will need someone to drive you home.
Exciting New Lens Options In the past, all lens implants were of a type called a “monofocal” lens implant. A monofocal lens implant provides excellent vision after cataract surgery, for one set distance only — usually for seeing things at a distance and thus does not correct presbyopia meaning it does not enable you to see close objects or read without reading glasses or bifocals. For seeing at a distance, such as looking at signs when driving, going to a movie or going to a ball game. a monofocal lens implant will provide the vision you need to see clearly. With a monofocal lens implant you will most likely need to wear eyeglasses for any type of near vision activities, such as reading, sewing, playing cards or writing, which would require you to wear glasses.
Today, we are able to offer you the choice of a presbyopia correcting multifocal lens implant. A presbyopla correcting multifocal lens implant provides excellent vision after cataract surgery at a variety of distances. Depending on your specific vision requirement, there are several types of presbyopia correcting multifocal lens implants that your eye surgeon might suggest, including, the ReZoom lens, the Restor lens, and the Crystalens.
Corneal transplant procedures may restore vision to otherwise blind eyes in some cases, and, of all tissue transplants, the most successful is a corneal transplant. There are many conditions in which corneal transplantation may be considered to improve vision.
The entire cornea is replaced in conditions such as scarring and keratoconus. However, only the back surface of the cornea may replaced in certain diseases including Fuchs’ corneal dystrophy, and pseudophakic bullous keratopathy, which is a corneal decompensation that occasionally follows cataract surgery. Pseudophakic bullous keratopathy causes decreased vision and pain as the corneal surface is irregular, and if severe, can require a full corneal transplant. Other indications for a full corneal transplant include corneal ulceration, herpes simplex and zoster viral infections leading to scarring, congenital corneal opacities, and chemical burns of the eye.
CORNEAL TRANSPLANTATION SURGICAL
A complete pre-operative evaluation will be required prior to surgery. The surgeon will make every attempt to confirm retinal and optic nerve function prior to surgery, so as to avoid cases in which visual improvement is unlikely. The majority of adult patients may have surgery under local anesthesia. General anesthesia will likely be required for children, anxious, or uncooperative patients.
In full corneal transplants (penetrating keratoplasty, or PKP), after the eye is cleaned and draped, the surgeon measures the cornea. Then the donor cornea is prepared using a punch or corneal trephine to create the corneal ‘button,” or the transplanted cornea. The diseased, or scarred, cornea is then removed using a corneal trephine, creating a “bed” for the transplant cornea. Finally, the donor cornea is gently attached into place with ultra-fine sutures (approx, one-third the thickness of human hair).
In partial corneal transplants (descemet stripping endothelial keratoplasty, or DSEK), after the eye is cleaned and draped, the surgeon removes the diseased back surface of the cornea through a small incision. The donor cornea is cut in order to separate the healthy back layer, which is inserted into the front part of the eye. An air bubble is then placed and pushes the donor tissue up against the back surface of the patient’s cornea. The eye’s natural pumping mechanism will attach the donor cornea as the air absorbs.
Advances in corneal transplantation now provide many patients with successful surgical options for restoring sight and a normal ocular surface.
GLAUCOMA – The Silent Threat!
WHAT IS GLAUCOMA?
Glaucoma is commonly associated with slow, progressive loss of peripheral vision. Although there are many types of glaucoma, “open angle glaucoma” is the most common. Loss of vision is painless and usually not noticed by the patient. It is a leading cause of blindness. The incidence increases with age. that is, it becomes more common as a patient ages. Regular testing of the peripheral visual field is important in identifying those at risk and in monitoring treatment plans.
COMMON TYPES OF GLAUCOMA:
“Open Angle Glaucoma” is very common (the most common in the United States). We try to identify those at risk before loss of vision occurs. Risk factors include, race, family history, hypertension, diabetes, appearance of the optic nerve and eye pressure. Therapy usually includes drops, but may also involve specialized glaucoma surgery, including laser. It is painless and there are usually no symptoms noted by the patient. Only thorough examination can determine if you have glaucoma.
“Narrow Angle Glaucoma” is somewhat uncommon in the United States, but is much more prevalent in Asian countries (this is the type that may be precipitated by certain over-the-counter cold medicines). Patients can complain of eye pain, headache, halos around lights and nausea. Definitive laser treatment is usually helpful in this condition.
“Angle Recession Glaucoma” is associated with severe blunt trauma. This type of glaucoma results in higher intraocular pressure due to damage to the drainage portion of the eye (the trabecular meshwork). Patients usually do not experience symptoms and it may take years for the glaucoma to develop.
Other types of Glaucoma include pigmentary dispersion, phacomorphic, phacolytic and uveitic. These types of glaucoma are less common, yet can be detected by thorough eye examination.
TREATMENT OF GLAUCOMA
Requires monitoring eye pressure and measuring changes in the peripheral field. “Control” of glaucoma usually means that the eye pressure is at an acceptable level and that there has been little or no loss of the visual field, as measured by a visual field analyzer. Although there are many risk factors for developing glaucoma, control of eye pressure is the mainstay of therapy.
Intraocular pressure may be controlled by a variety of ways:
Topical Drops are usually the first line of treatment. Taken on a daily basis, these usually are very effective in controlling eye pressure. Over time, these drops may become less effective and your doctor may elect to change your medications. Drops either decrease production of intraocular fluid or increase its absorption.
Oral Medications may also be effective, but may have more systemic side effects. If tolerated, these can be useful adjuncts to other glaucoma treatments.
Selective Laser Trabeculoplasty (SLT) is extremely successful in lowering eye pressure in certain types of glaucoma such as open angle glaucoma, pigment dispersion syndrome and pseudo-exfoliation. Treatment is focused on the trabecular meshwork (responsible for fluid drainage from the eye) to increase fluid outflow and thereby reduce eye pressure. This treatment may replace topical drops and can be repeated, if necessary.
Laser Iridotomy involves the creation of a small hole in the iris (colored portion of eye) to permit an alternate channel or pathway for intraocular fluid to reach the trabecular meshwork and be drained from the eye. This procedure is usually indicated in narrow angle glaucoma.
Trabeculectomy is a type of surgery whereby intraocular fluid (aqueous humor) is directed to the outside of the eye to increase its absorption. This is commonly performed when medications fail, although some practitioners may recommend this as initial treatment.
Seton or shunt placement for glaucoma also involves the creation of an alternate pathway for aqueous humor to be absorbed outside the eye. It, too, is not a first line of treatment and may be reserved for very difficult situations.
The treatment and management of glaucoma is essential in preventing long term vision loss.
The key to successful management is early detection and regular follow-up examination.
Oculoplastic surgeons perform cosmetic and reconstructive surgery of the eyelids, lacrimal system, and orbit. The advantage of having a cosmetic or corrective eyelid surgery performed by an oculoplastic specialist is that the physician can perform a full medical eye evaluation and then determine how much correction with be tolerated without over-correcting the eyelids. Blepharoplasty is a common procedure, excess skin and fatty tissue are removed from around the eyes. Drooping eyebrows can also be corrected at the same time.
Blepharoplasty is eyelid surgery that can be done to improve both visual function and cosmetic appearance. Excessive upper eyelid tissue can block the upper field of vision. Correction of overhanging skin folds will improve the function of the upper eyelid and peripheral vision. Even if vision is not affected, blepharoplasty may be performed to improve a sagging, tired appearance.
In addition to changes in appearance and a limited field of vision, excess eyelid tissue can also cause physical discomfort. The weight of the excess eyelid tissue may cause brow ache and fatigue. In some cases, excess skin may cause the eyelashes to turn in and irritate the eye.