Bringing Our Community Together

Category archive

Dr. Mark Siegel, MD FAAO

Health, Sea Island Ophthalmology, eyes

New treatments for dry age-related macular degeneration

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

By Dr. Mark S. Siegel

Macular degeneration is currently the leading cause of visual impairment in the U.S.

Breakthrough treatment with anti-VEGF eye injections such as Avastin (bevacizumab, Genentech), Lucentis (ranibizumab, Genentech) and Eylea (aflibercept, Regeneron) has almost arrested the progression of the wet form of the disease.

However, almost 80 percent of people diagnosed with age-related macular degeneration (AMD) have the non-neovascular (dry) or atrophic subtypes.

The American Academy of Ophthalmology notes that the most advanced form of non-neovascular AMD, known as geographic atrophy (GA), can occur as early as in intermediate AMD or (more typically) in advanced AMD.

Estimates predict advanced AMD will impact as many as 3 million people in at least one eye by 2020.

The growing number of aging Americans underscores the need for treatments that can prevent progression of and/or treat advanced AMD.

Trials underway 

Surprisingly, no treatments are currently available for the prevention of GA. Evidence from the Age-Related Eye Disease Study (AREDS) suggests antioxidant vitamin and mineral supplementation may help prevent the progression to neovascular AMD, but the study failed to show that vitamin supplementation decreased progression to geographic atrophy.

Even in AREDS2, when beta-carotene was replaced with lutein/zeaxanthin to decrease the risk of lung cancer, the new formulation also failed to show decreased progression to GA.

Clinical studies are underway to further elucidate and understand the mechanisms of dry AMD and to evaluate new therapeutics directed at slowing the progression.

There are currently two large phase 3 trials underway for the treatment of GA. The FILLY study assesses the safety, tolerability and evidence of activity of multiple intravitreal (IVT) injections of APL-2 (Apellis Pharmaceuticals) for patients with GA. The second is a multicenter, randomized, double-masked, sham-controlled study to investigate IVT injections of lampalizumab in patients with GA.

The discovery of complement byproducts in drusen led to associations between complement dysregulation and AMD.

Thus, several researchers are evaluating the complement cascade as a clinical therapeutic target for non-neovascular AMD.

Factor D is considered a critical early component of the alternative pathway that involves complement factor H. Factor D is an upstream of factor B and other AMD-associated proteins, making it a potential powerful target for treatment.

Anti-inflammatory agents under development include lampalizumab, fluocinolone, glatiramer acetate, sirolimus, eculizumab and ARC-1905.

These are but the tip of the iceberg of compounds under development for advanced AMD or GA.

Visual cycle inhibitors are among those in latter-stage development and include fenretinide, ACU-4429 and ALK-001.

These compounds down-regulate the visual cycle to decrease the accumulation of the toxic waste products of retinal metabolism. Amyloid-beta has been found in drusen, and RN6G and GSK933776 are in development to regulate amyloid-beta accumulation.

Neuroprotective drugs are also under development, including UF-021, ciliary neurotrophic factor and brimonidine tartrate intravitreal implant.

Topical agents such as MC-1101 are attempting to slow AMD by increasing choroidal perfusion.

Stem cell therapies including HuCNS-SC and MA09-hRPE are also under investigation as potential treatments for GA.

At this point, it is too early to tell which — if any — of these treatments will become a standard of care.

Dr. Mark S. Siegel is the Medical Director at Sea Island Ophthalmology on Ribaut Road in Beaufort. 

Visit www.seaislandophthalmology.com for more information.

New class of glaucoma drugs in development

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

By Dr. Mark S. Siegel

Primary Open Angle Glaucoma is the most common type of glaucoma. An increase in eye pressure, intraocular pressure (IOP), occurs slowly over time, leading to vision loss. Higher IOP is thought to be the result of changes in the eye that lead to an obstruction in the outflow of fluid, called aqueous humor.

Large clinical studies have shown that, with reduction in IOP, optic nerve damage and progressive visual loss can be slowed or minimized.

Glaucoma therapies

Current drug treatments are directed towards lowering IOP. Treatments to reduce IOP rely on topical eye drop medications, laser and or conventional surgery.

Many patients require more than one drug to control IOP, and despite effective current therapies, they don’t work for all patients.

Current glaucoma medications reduce IOP by either reducing the production of fluid in the eye, or by increasing its outflow. Prostaglandins, which increase outflow, are now the most prescribed glaucoma treatment worldwide.

Glaucoma drugs

A new class of glaucoma drugs promises to act specifically on the eye’s drainage canals, called the trabecular meshwork, a main outflow and blockage site in glaucoma.

Rho kinase (ROCK) inhibitors target cells in the trabecular meshwork to enhance aqueous humor outflow. Aqueous humor is a clear fluid that maintains the intraocular pressure.

In research models of glaucoma, ROCK inhibitors have been shown to reduce cellular “stiffness” and enhance outflow through the trabecular meshwork, thereby reducing IOP. No drugs currently on the market enhance the eye’s fluid outflow in this way. Therefore this is a novel and unique target and approach to lowering IOP.

ROCK inhibitors are not yet approved and available for glaucoma patients.

Two U.S. companies, Aerie and Altheos, are currently in clinical research development with topical ROCK inhibitors to lower IOP.

Research data has shown that ROCK inhibition has the potential to offer neuroprotective and anti-inflammatory effects as well as enhance blood flow to the optic nerve, all of which could benefit glaucoma patients.

The ophthalmic community looks forward to and awaits the clinical research data as it becomes available for this potentially exciting class of drug compounds.

Can fish oil help dry eye?

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

By Dr. Mark S. Siegel

While artificial tears or ointments are a common treatment for dry eye, studies suggest consuming omega-3 fatty acid supplements may also provide relief.

Omega-3 oils appear to improve function in the eye’s meibomian glands, which produce the oily part of tears. Improved function of those glands can ease dry eye symptoms.

Dry eye becomes more common as a person ages. The problem develops when the eye cannot maintain a healthy coating of tears. Dry eye can be caused by hormonal changes brought on by menopause. There are a number of other causes, including a dry environment or workplace (such as wind or air conditioning), sun exposure, smoking or secondhand smoke exposure and many medications.

The National Eye Institute notes that in some patients with dry eye, supplements or dietary sources of omega-3 fatty acids (such as tuna fish) may decrease symptoms of irritation.

Many studies have shown that the omega-3s in fish oil are believed to reduce inflammation. If inflammation of the eyelids or surfaces of the eye worsens dry eye, it makes sense that a supplement could help the problem.

Since dry eye is pretty complex, and there is no cure, it seems reasonable that by treating the inflammation, one can improve some of the symptoms.

A study of more than 32,000 women from the Women’s Health Study published in 2005 found those who consumed the most omega-3 fats from fish had a 17 percent lower risk of dry eye, compared with women who ate little or no seafood. More recently, a study in the International Journal of Ophthalmology concluded omega-3 fatty acids have a definite role for dry eye syndrome.

Omega-3 oils may also help in the treatment of other eye diseases. The oils may reduce growth of abnormal blood vessels that occur in age-related macular degeneration and other retinal vascularization diseases.

Talk to your doctor to find out whether omega-3 supplements are right for you.

Protect your eyes from sun damage

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

The days are longer, the sun is hotter, the beach beckons and out comes the sunscreen.

But summer revelers looking forward to sizzling hot fun in the sun shouldn’t overlook their eyes when it comes to protecting themselves from damaging ultraviolet rays.

In support of UV Safety Month in July, Sea Island Ophthalmology joins the American Academy of Ophthalmology in sharing information on how to keep eyes safe from sun damage.

Excess sun exposure can put people at risk of serious short-term and long-term eye problems. If eyes are exposed to strong sunlight for too long without protection, UV rays can burn the cornea and cause temporary blindness in a matter of hours. Long-term sun exposure has also been linked to an increased risk of cataracts, age-related macular degeneration, cancer and growths on or near the eye.

Here are five things people can do to cut their risk of eye damage from the sun:

• Wear the right sunglasses: Look for those labeled “UV400” or “100 percent UV protection” when buying sunglasses. Less costly sunglasses with this label can be just as effective as the expensive kind. Darkness or color doesn’t indicate strength of UV protection. UV rays can go through clouds, so wear sunglasses even on overcast days. And while contact lenses and lens implants may offer some benefit, they cannot protect the entire eye area from burning rays.

• Don’t stare at the sun: Sun worshippers take note: directly gazing at the sun can burn holes in the retina, the light-sensitive layer of cells in the back of the eye needed for central vision. This condition is called solar retinopathy. While rare, the damage is irreversible.

• Check your medication labels: One in three adults uses medication that could make the eyes more vulnerable to UV ray damage, according to a sun safety survey by the academy. These include certain antibiotics, birth control and estrogen pills, and psoriasis treatments containing psoralen. Check the labels on your prescriptions to see if they cause photosensitivity. If so, make sure to protect your skin and eyes or avoid sun exposure when possible.

• Put a lid on it: In addition to shades, consider wearing a hat with a broad brim. They have been shown to significantly cut exposure to harmful rays. Don’t forget the sunscreen!

• Don’t drive without UV eye protection: Don’t assume that car windows are protecting you from UV light. A recent study found that side windows blocked only 71 percent of rays, compared to 96 percent in the windshield.  Only 14 percent of side windows provided a high enough level of protection, the researchers found. So when you buckle up, make sure you are wearing glasses or sunglasses with the right UV protection.

At the end of the day, you want to retain fond memories and experiences during summer celebration, not skin cancer and blinding eye disease.

For more information, visit www.seaislandophthalmology.com.

Vitamin see: foods rich in vitamin C may help slow cataracts

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

By Dr. Mark S. Siegel

What do grapefruit, broccoli and strawberries have in common?

They are foods loaded with vitamin C, which could help slow cataract progression, according to a British study.

Cataracts are a clouding of the eye’s lens that happens naturally with age. The condition is the leading cause of blindness in the world, according to the World Health Organization.

Researchers from King’s College London examined data from more than 1,000 pairs of female twins to see what factors may help keep cataracts at bay. They tracked intake of vitamin C and other nutrients from food and supplements. They also recorded how opaque the subjects’ lenses were at around age 60, with a follow-up on 324 sets of twins about 10 years later.

Women who reported consuming more vitamin C-rich foods had a 33 percent risk reduction of cataract progression over the decade, according to the study. Their lenses overall were more clear.

Although we cannot totally avoid developing cataracts, we may be able to delay their onset and keep them from worsening significantly by eating a diet rich in vitamin C. The researchers noted that the findings only pertain to vitamins consumed through food and not supplements.

Vitamin C is a powerful antioxidant. The fluid inside the eyeball is normally high in a compound similar to vitamin C, which helps prevent oxidation that results in a clouded lens. Scientists believe more vitamin C in the diet may increase the amount present around the lens, providing extra protection.

Because the study was done in twins, the team was also able to calculate how much of a role genetics versus environmental factors play in cataract progression. While environmental factors, such as diet, accounted for 65 percent, genetic factors only accounted for 35, indicating that diet and lifestyle may outweigh genetics.

The study, “Genetic and Dietary Factors Influencing the Progression of Nuclear Cataract“ will be published this June in Ophthalmology, the official journal of the American Academy of Ophthalmology.

Dropless Cataract Surgery: What are the potential risks?

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

By Dr. Mark S. Siegel

Cataract surgery continues to evolve, with microincisional clear corneal incisions, femtosecond lasers, new imaging modalities, and improved lens implants. However, the published literature is having trouble keeping up with clinical practice. Despite the ongoing change, one concern remains constant: endophthalmitis (infection) prophylaxis. The use of perioperative povidone-iodine, a lid speculum, and drape with isolation of lids and lashes, and sterile preparation, is effective in limiting the incidence of endophthalmitis after cataract surgery.

The recent advent of “dropless” cataract surgery via transzonular ocular injections of TriMoxi or TriMoxiVanc, offers another option of infection prophylaxis. As some cataract surgeons consider adopting dropless cataract surgery it is important to balance the potential complications and risks involved with this technique.

These combinations of antibiotics and steroids are delivered to the anterior vitreous (jelly that fills the back of the eye) by injection through the zonules (tiny spider web-like ligaments that anchor the lens to the wall of the eye). This is intended to mitigate the need for post-operative topical drops. Drops can be costly, can irritate the surface of the eye, can be difficult for some patients to administer and can be burdensome to prescribers. Though post-operative drops are less than ideal, this new mode of dropless infection prophylaxis contains some inherent risks.

A clear concern is compounding errors. There have been reports of dilutional errors with intraocular antibiotics that have resulted in complications including macular swelling, retinal detachment, macular infarction, toxic anterior segment syndrome (severe inflammation) and a large outbreak of Fusarium endophthalmitis.

The pharmacokinetics of TriMoxi(+/-) Vanc is unclear when placed in the anterior vitreous. These antibiotics have the shortest half-life of current intravitreal antibiotics being used (1.7 hours). Vancomycin has a half-life of 25.1 hours. Routine topical antibiotics are able to produce concentrations inside the eye for a week post-operatively. While one European study showed decreased rates of endophthalmitis with injected antibiotics, all arms of the study used 6 days of topical postoperative antibiotics! The question remains: is the duration of coverage with injected antibiotics without topical antibiotics adequate?

Antibiotic resistance is another consideration when using TriMoxi. Emerging resistance has been identified. A recent review found resistance rates to moxifloxacin has increased from 21% in 1995 to 62% in 2014.

The use of prophylactic vancomycin in TriMoxiVanc during routine cataract surgery is controversial. The Centers for Disease Control issued guidelines in 1995 specifically discouraging the use of vancomycin in routine surgical prophylaxis because of increasing bacterial resistance. The risk of fueling the emerging resistance to vancomycin for an unproven practice is worrisome. Given that there are more than 3 million cataract surgeries performed in the United States each year, exposure of the ocular surface to low doses of vancomycin could result in an increase in vancomycin resistant bacteria.

Another unknown is the risk of steroid-induced ocular hypertension (elevated eye pressure) associated with TriMoxi(+/-) Vanc. It is well known that topical steroids can induce ocular hypertension, but drops are easily discontinued, whereas injected intraocular steroids are not. Currently there is a paucity of literature addressing transzonular triamcinolone (the steroid component in TriMoxi) and its associated ocular hypertension risk. Furthermore, the use of triamcinolone leaves patients with obscured vision and floaters for the first week or more. Patient complaints of foggy vision postoperatively have led some cataract surgeons to discontinue the product. Many randomized trials show that topical nonsteroidal anti-inflammatory drugs (NSAIDS) are superior to topical steroids in reducing post-operative macular swelling after cataract surgery. Thus, regardless of the intraocular steroid and antibiotic used, it is likely that a topical NSAID will need to be prescribed.

Technical and mechanical issues must be considered in addition to issues of bacterial resistance, compounding risks, steroid-induced elevated eye pressure, and post-operative foggy vision. In patients with lens zonular weakness (pseudoexfoliation), intraocular lens (IOL) decentration or dislocation may occur. The impact of this technique for premium IOL decentration could create significant visual disturbance. Since most patients using blood thinners do not discontinue this medication, there could be intraocular hemorrhage from inadvertent cannula contact with the iris ciliary muscle. Finally, very short eyes may not have the space to accommodate the injected volume of these antibiotic and steroid preparations.

Today’s cataract surgery is safer for the patient and shorter in duration than in decades past. Improvements in technology, techniques, and training have led to improved outcomes for our patients. Although the concept of dropless cataract surgery is clearly attractive, cataract surgeons should consider the serious issue of bacterial resistance and the unnecessary risk of the transzonular delivery of TriMoxi(+/-) Vanc. In an era of increasing cost-benefit analysis where physicians will be judged on outcomes and the allocation of limited healthcare resources, the value of dropless cataract surgery remains uncertain, risky and currently not the standard of care.

February is Age-Related Macular Degeneration Awareness Month

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

By Dr. Mark S. Siegel

Macular degeneration is a major cause of irreversible vision loss in the United States and around the world. As many as 11 million Americans have some form of macular degeneration. To observe Age-Related Macular Degeneration (AMD) Awareness Month, Sea Island Ophthalmology is offering tips for prevention, early detection, and treatment of the condition.

Facts about Age-Related Macular Degeneration (AMD)

The number of people living with any form of macular degeneration is similar to that of those who have been diagnosed with all types of invasive cancers.

As many as 11 million people in the United States have some form of AMD. This number is expected to double by 2050.

AMD is the result of deterioration of a central area of the retina called the macula, which is the location of central vision. This deterioration can make vision become blurry or wavy. It can also result in a blind spot in the center of your vision.

Age is a major risk factor for developing AMD. Other risk factors include: a history of smoking, hypertension, and family history. AMD is more common among women and Caucasians but is seen among all races.

There are two types of AMD: dry (atrophic) and wet (neovascular or exudative). Most AMD starts as the dry type and in 10-20 percent of individuals, it progresses to the wet type.

Age-related macular degeneration is always bilateral (i.e., occurs in both eyes), but does not necessarily progress at the same pace in both eyes. It is therefore possible to experience the wet type in one eye and the dry type in the other.

Tips for Age-Related Macular Degeneration (AMD) Prevention and Treatment

If you have a family history of AMD, get a comprehensive dilated eye exam yearly after the age of 50.

AMD occurs less often in people who exercise, avoid smoking, and eat nutritious foods including green leafy vegetables and fish. If you already have AMD, adopting these habits may help you keep your vision longer.

Although some vision loss from AMD is irreversible, effective treatments can slow down progression or in some cases reverse vision deterioration.

Nutritional supplement formulations containing antioxidants and zinc (studied in the AREDS and AREDS2 clinical trials) have been shown to slow the disease in those who have intermediate AMD and those with advanced AMD in only one eye.

Anti-VEGF injections (medication specifically aimed at stopping the progression of the abnormal blood vessels that cause the vision loss) are an effective treatment for the wet or neovascular form of AMD and may control or reverse vision loss if administered shortly after the onset of vision loss. Early recognition of vision change, evaluation by an ophthalmologist, and starting proper medical treatment may be sight-saving.

Anti-Complement treatments and Stem cell therapies are promising treatments for the advanced dry form of AMD, which are being studied in multiple clinical trials.

January is Glaucoma Awareness Month

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

By Dr. Mark S. Siegel

January is National Glaucoma Awareness Month, an important time to spread the word about this sight-stealing disease.

Currently, more than 3 million people in the United States have glaucoma. The National Eye Institute projects this number will reach 4.2 million by 2030, a 58 percent increase.

Glaucoma is called “the sneak thief of sight”. There are no symptoms and once vision is lost, it’s permanent. Nearly 40% of vision can be lost without a person noticing.

Glaucoma is the leading cause of preventable blindness. Moreover, among African American and Latino populations, glaucoma is more prevalent. Glaucoma is 6 to 8 times more common in African Americans than Caucasians.

And among Hispanics in older age groups, the risk of glaucoma is nearly as high as that for African-Americans. Also, siblings of persons diagnosed with glaucoma have a significantly increased risk of having glaucoma.

Over 3 million Americans, and over 60 million people worldwide, have glaucoma. Experts estimate that half of them don’t know they have it. Combined with our aging population, we can see an epidemic of blindness looming if we don’t raise awareness about the importance of regular eye examinations to preserve vision. The World Health Organization estimates that 4.5 million people worldwide are blind due to glaucoma.

What is Glaucoma?

Glaucoma is a group of eye diseases that gradually steal sight without warning. Although the most common forms primarily affect the middle-aged and the elderly, glaucoma can affect people of all ages.

Vision loss is caused by damage to the optic nerve. This nerve acts like an electric cable with over a million wires. It is responsible for carrying images from the eye to the brain.

There is no cure for glaucoma—yet. However, medication or surgery can slow or prevent further vision loss. The appropriate treatment depends upon the type of glaucoma among other factors. Early detection is vital to stopping the progress of the disease.

Types of Glaucoma

There are two main types of glaucoma: primary open-angle glaucoma (POAG), and angle-closure glaucoma. These are marked by an increase of intraocular pressure (IOP), or pressure inside the eye. When optic nerve damage has occurred despite a normal IOP, this is called normal tension glaucoma.

Secondary glaucoma refers to any case in which another disease causes or contributes to increased eye pressure, resulting in optic nerve damage and vision loss.

Regular Eye Exams are Important

Glaucoma is the second leading cause of blindness in the world, according to the World Health Organization. In the most common form, there are virtually no symptoms. Vision loss begins with peripheral or side vision, so if you have glaucoma, you may not notice anything until significant vision is lost.

The best way to protect your sight from glaucoma is to get a comprehensive eye examination. Then, if you have glaucoma, treatment can begin immediately.

Risk Factors

Are you at risk for glaucoma? Those at higher risk include people of African, Asian, and Hispanic descent. Other high-risk groups include: people over 60, family members of those already diagnosed, diabetics, and people who are severely nearsighted. Regular eye exams are especially important for those at higher risk for glaucoma, and may help to prevent unnecessary vision loss.

Choose safe toys this holiday season

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

By Dr. Mark S. Siegel

No one chooses gifts with the intent to harm, but some popular children’s toys can cause serious eye injuries. According to the U.S. Consumer Product Safety Commission, more than 265,000 toy-related injuries were treated in emergency rooms in 2012, and almost half of these injuries affect the head or face – including the eyes. Unfortunately, most of these injuries happen to children under age 15.

Give children the appropriate protective eyewear along with their new skis, snowboards, and sleds.
Give children the appropriate protective eyewear along with their new skis, snowboards, and sleds.

‘You’ll shoot your eye out’

Some propelling toys, like air soft guns, BB guns, paintball guns and darts can be particularly hazardous, with the potential to cause serious eye injuries such as corneal abrasion, ocular hyphema (bleeding inside the eye), traumatic cataract, increased intraocular pressure and even permanent vision loss.

Another dangerous toy category is those with laser components, which have increased in power and decreased in price over the years. Lasers can be especially hazardous when used in toys that are aimed, such as a laser gun. Blue light lasers are particularly dangerous, as they are more likely to cause retinal injury compared with green or red lasers. Studies show that exposure for even fractions of a second to high-powered blue handheld laser devices can cause serious eye injuries – including macular holes – which often require surgical intervention. In addition, the FDA warns that laser pointers are not toys and should only be used with adult supervision.

The good news is that following these toy safety tips can easily prevent most eye injuries:

Top Toy Safety Tips:

  • Avoid purchasing toys with sharp, protruding or projectile parts.
  • Make sure children have appropriate supervision when playing with potentially hazardous toys or games that could cause an eye injury.
  • Ensure that laser product labels include a statement that the device complies with 21 CFR (the Code of Federal Regulations) Subchapter J.
  • Along with sports equipment, give children the appropriate protective eyewear with polycarbonate lenses. Check with your ophthalmologist to learn about protective gear recommended for your child’s sport.
  • Check labels for age recommendations and be sure to select gifts that are appropriate for a child’s age and maturity.
  • Keep toys that are made for older children away from younger children.

If your child experiences an eye injury from a toy, seek immediate medical attention.

Are you a candidate for laser cataract surgery?

in Contributors/Dr. Mark Siegel, MD FAAO/Health by

By Dr. Mark S. Siegel

The femtosecond laser technology that brought new levels of safety, accuracy and predictability to LASIK surgery is also advancing cataract surgery. In our office, we call the procedure Refractive Laser-Assisted Cataract Surgery (ReLACS), but it also is known generally as laser cataract surgery.

In laser cataract surgery, an advanced femtosecond laser replaces or assists in the use of a hand-held surgical tool for the following steps in cataract surgery:

1 The corneal incision

2 The anterior capsulotomy

3 Lens and cataract fragmentation

4 Astigmatism correction at the time of surgery

Use of a laser can improve the precision, accuracy and reproducibility of each of these steps, potentially reducing risks and improving visual outcomes of cataract surgery.

The Corneal Incision

Traditional cataract surgery is one of the most frequently performed surgeries and also one of the most safe and effective, with predictable outcomes. It is highly dependent on surgeon skill, volume and experience.

Optical coherence tomography is an imaging technology that helps your cataract surgeon to plan the location and depth of incisions made during a laser-assisted cataract surgery procedure. OCT scans offer high-resolution and even cross-sectional images, to make the cataract surgery as precise as possible.
Optical coherence tomography is an imaging technology that helps your cataract surgeon to plan the location and depth of incisions made during a laser-assisted cataract surgery procedure. OCT scans offer high-resolution and even cross-sectional images, to make the cataract surgery as precise as possible.

The first step in cataract surgery is making an incision in the cornea. In manual cataract surgery, the eye surgeon uses a hand-held metal or diamond blade to create an incision in the area where the cornea meets the sclera. This incision allows the surgeon to gain access to the interior of the eye to break up and remove the cataract, which is a clouding of the eye’s natural lens that is located right behind the pupil. Next, an intraocular lens (IOL) is inserted and implanted, to replace the cloudy natural lens.

The corneal incision is made in a special way so it will self-seal when surgery is complete, without any need for stitches.

In laser cataract surgery, the surgeon creates a precise surgical plan for the corneal incision with a sophisticated 3-D image of the eye called an OCT (optical coherence tomography). The goal is to create an incision with a specific location, depth and length in all planes, and with the OCT image and a femtosecond laser it can be performed exactly without the variable of surgeon experience or patient cooperation.

This is important not only for accuracy but also for increasing the likelihood that the incision will be self-sealing at the end of the procedure, which reduces the risk of infection.

The Capsulotomy

A very thin, clear capsule surrounds the eye’s natural lens. In cataract surgery, the front portion of the capsule is removed in a step called an anterior capsulotomy, to gain access to the cataract.

It is very important that the remainder of the lens capsule that remains intact in the eye is not damaged during cataract surgery, because it must hold the artificial lens implant in place for the rest of the patient’s life.

In traditional cataract surgery, the surgeon creates an opening in the capsule with a small needle and then uses that same needle or a forceps to tear the capsule in a circular fashion.

In laser cataract surgery, the anterior capsulotomy is performed with a femtosecond laser. Studies have shown that capsulotomies performed with a laser have greater accuracy and reproducibility.

Studies also have shown that laser capsulotomies enable better centering of the intraocular lens, and IOL positioning is a significant factor in determining final visual outcomes.

Lens and Cataract Fragmentation

After the capsulotomy, the surgeon now has access to the cataract to remove it. In traditional cataract surgery, the ultrasonic device that breaks up the cataract is inserted into the incision. During this phacoemulsification procedure, the ultrasound energy can lead to heat buildup in the incision, which sometimes can burn the incision and negatively affect the visual outcome by actually inducing astigmatism.

An incision burn also has a higher chance of leaking and sometimes needs multiple sutures to close. The smaller the incision we use, the more this issue is important to consider.

The laser, on the other hand, softens the cataract as it breaks it up. By breaking up the cataract into smaller, softer pieces, less energy should be needed to remove the cataract, so there should be less chance of burning and distorting the incision.

Laser cataract surgery may also reduce the risk of capsule breakage. After the calculation of the proper implant power, there is no step more important for visual outcome than preservation of the capsule that the natural lens sat in. This capsule is as thin as cellophane wrap and it’s important that the portion that is left inside the eye after cataract surgery is undamaged, so it can hold the IOL in the proper position for clear,
undistorted vision.

The reduced phacoemulsification energy required in laser cataract surgery may also make the procedure safer to the inner eye, which reduces the chance of certain complications, such as corneal decompensation or retinal complications.

Astigmatism Correction at the Time of Cataract Surgery

To reduce the need for prescription eyeglasses or reading glasses after cataract surgery, it is important that little or no astigmatism is present after implantation of IOLs, especially presbyopia-correcting multifocal IOLs.

Astigmatism usually is caused by the cornea being more curved in one meridian than others (in other words, it’s shaped somewhat like a football). To reduce astigmatism, small incisions can be placed in the periphery of this more curved meridian; as the incisions heal, this meridian flattens slightly to give the cornea a rounder, more symmetrical shape (like a baseball).

This procedure is called limbal relaxing incisions (LRI) or astigmatic keratotomy (AK). Surgeons can perform LRI or AK manually with a diamond blade, and it is quite effective in reducing astigmatism.

During refractive laser-assisted cataract surgery, the OCT image can be used to plan laser LRI or AK incisions in a very precise location, length and depth. This increases the accuracy of the astigmatism-reducing procedure and increased the probability of good vision without glasses after cataract surgery.

This LenSx femtosecond laser system has laser data entry at left, a joy stick control and an OCT screen at right, which offers the surgeon all-important guidance during laser-assisted cataract procedures. (Images: Alcon)
This LenSx femtosecond laser system has laser data entry at left, a joy stick control and an OCT screen at right, which offers the surgeon all-important guidance during laser-assisted cataract procedures. (Images: Alcon)

Laser Cataract Surgery Systems Currently Available

A number of medical device companies worldwide manufacture systems for performing laser cataract surgery. There are four Systems that have attained FDA approval and are currently available for laser-assisted cataract surgery performed in the United States. We use the LenSx system in our practice.

• LenSx. The LenSx system (Alcon) was the first femtosecond laser system to gain FDA approval for cataract surgery performed in the U.S. The LenSx system is approved for corneal incisions, capsulotomies and lens (cataract) fragmentation and has been used in more than 400,000 cataract refractive procedures worldwide, according to Alcon

Cost of Laser Cataract Surgery

Refractive laser-assisted cataract surgery costs more than conventional options. Medicare or private health insurance does not cover extra costs of laser cataract surgery since the laser is used to treat astigmatism or is used in conjunction with advanced technology IOLs, which is not a covered service. You will pay extra out-of-pocket per eye for a laser-assisted procedure.

Conclusion

It is important to put this new technology into proper perspective. Manual cataract surgery is very effective and successful. People who do not want to invest out-of-pocket money in laser cataract surgery can still feel confident about the manual approach.

But if you want the best possible vision, laser cataract surgery is more precise, accurate and gentle. A more accurate and precise incision, capsulotomy and astigmatic correction may help you achieve your goal of less dependence on glasses after cataract surgery.

Cataract surgeons who use lasers say that their advantages are especially evident when it comes to advanced technology, premium implants such as presbyopia-correcting multifocal IOLs and toric IOLs for astigmatism. The advantages can include better lens placement and therefore more accurate visual outcomes.

To decide if laser cataract surgery is the best choice for you, ask your cataract surgeon for more information about this exciting technology during your preoperative exam and consultation.

1 2 3 7
Go to Top