Selecting Your Best Vision Correction Options

Today technology has evolved to a point where patients either with normal refractive errors such as nearsightedness, farsightedness, astigmatism and presbyopia or those with ocular diseases that require specialized vision correction options such as those with keratoconus all have spectacular alternatives to maximize their visual performance. With the multitude of choices available, how does an individual make the decision which to take advantage of? Well let’s begin by saying that the input from your eye care professional is critically important. You need to be properly educated not only about the various options that are applicable to your individual situation but about the advantages and disadvantages of these options.eye glass fitting vision correction options

Normal Refractive Error Options

Let’s begin by discussing vision correction options available to those with normal refractive errors. Basically stated, these individuals have the ability to utilize spectacles, contact lenses or if they are appropriate candidates, consider the refractive surgical alternatives.

Glasses
Today spectacle lens technology has evolved to the point where exceptional vision quality can be achieved with lens designs that allow for the selection of almost any frame size or shape. Thin lens technologies have enabled those with high prescription powers to not only see amazingly well, but to wear glasses that remain quite thin and attractive even with some of the most extreme prescription powers. Your eye care professional can discuss the various lens material options that best work for your situation. New high index materials are not only thin but are very light weight. A concern for some however can be the significantly higher costs associated with these lens materials. For those who need multifocals, new digital and free form progressive addition lenses (PALs) have dramatically increased the success rates associated with adaptation to PALs.

Contact Lenses
Contact lens alternatives for those with normal refractive errors have also dramatically developed technologically over the past years. Today virtually every patient with normal refractive error is a candidate to wear contact lenses. Developments such as astigmatic contacts, multifocal contacts, and hybrid (rigid center / soft periphery) contact lens designs along with the introduction and the tremendous growth in the use of single use daily disposable contacts has made one form or another of contact lenses something to consider for almost everyone. Today’s CLs are healthier, more comfortable and provide better vision than ever before. CLs have the advantage of superior peripheral vision, more natural vision “sensation” and obvious advantages for demanding physical activities. With contemporary contact lens materials and designs we have successfully addressed issues that limited many people in the past such as concerns of poor comfort due to dryness, contact lens vision instability and contact lens induced complications associated with over-wear and over-use of lenses. Your eye doctor should always present contact lens options to you regardless if you ask or not. So often patients think that they can’t wear contacts, so it does become the responsibility of your doctor to inform and educate you about CL alternatives.
contact lens vision correction options
Combination of Glasses and Contact Lenses
So how do you decide if you should be a contact lens wearer or a glasses wearer? Who said you have to? The two vision correction options are not mutually exclusive; in fact they are quite synergistic. All contact lens wearers should have an excellent pair of glasses to use. Contacts may be more cosmetically acceptable to many, they may be much better for various physical activities such as sports, however there are many times when glasses may be preferred such as at the end of a long day of contact lens wear, first thing in the morning before inserting your CLs, or on those days you just don’t want to bother with your CLs or simply prefer the look of your glasses for some situations. Today even the person who predominantly wears glasses can consider part time contact lens wear. Single use daily disposable (DD) CLs are the perfect option for such an individual. DD CLs are now even available in astigmatism and multifocal designs!

Refractive Surgery
Refractive surgery is also developing and is more effective and safer today than ever before. An experienced and skilled eye doctor is in the best position to consult with you in order to determine if you are an excellent candidate for the various refractive surgical options available. Again, having refractive surgery does not always eliminate your need for glasses or contact lenses. Although that would be the optimal outcome, many patients still use glasses and contact lenses after having refractive surgery. Typically the glasses and contact lenses are far less strong and are used significantly less often than prior to surgery. Some patients need them due to complications of surgery while others need them when outcomes did not perfectly correct vision and of course refractive surgery does not stop eyes from changing over the years, so many patients who had successful refractive surgery may experience vision changes years after surgery that require the use of glasses, contacts or both.

Irregular Refractive Error Options

Specialty Contact Lenses
Next let’s talk about choices in vision correction for those with irregular corneas and other conditions that are termed “medically necessary” vision correction cases. Individuals with irregular corneas such as those with keratoconus or post LASIK or other refractive surgery induced ectasias often require contact lenses that in essence “mask” the irregularity of the cornea. In the past this equated with the fitting of rigid corneal contact lenses, however today many other alternatives can be considered such as the fitting of scleral large diameter gas permeable contacts, hybrid CLs designed for irregular corneas and even combination systems of soft lenses with corneal gas permeable lenses (called “tandem” or “piggyback” CL systems). These CL alternatives provide advantages such as improved comfort, improved eye health response by limiting contact lens to cornea bearing, and improved contact lens positioning and stability which positively impacts visual performance.

Combination of Contact Lenses With Glasses
It should be clearly stated that spectacle lens alternatives still can have a significant role in the treatment of individuals with irregular corneas. Often glasses can be prescribed that provide adequate vision if even for part time and limited applications. While less severe cases may perform quite well with glasses as their primary modality of vision correction. Your doctor may need to modify the power of your glasses prescription in order for you to adapt to wearing glasses, however even a modified prescription power can frequently allow for some degree of visual function and allow for the ability to reduce the number of contact lens wearing hours during the day.

Surgical Procedures
Application of certain surgical and medical procedures such as intra-corneal ring segments (Intacs TM) or corneal collagen cross linking (CXL) for corneal irregularity can often help these patients in various ways and may allow for perhaps a less complex contact lens application or easier adaptation and improved function with glasses. Management of these diseases and conditions is quite complex and requires the expertise of doctors with extensive experience. Your doctor, if appropriately skilled and experienced can provide you with all of the required information and education so that you both can jointly decide on the best vision correction options for you.

In conclusion, patients today have numerous options for their vision correction. These options each have advantages and disadvantages but in most cases can be utilized synergistically. The role that your eye care professional plays in consultation and education of the vision correction alternatives applicable to you cannot be over stated. Vision is a precious gift and you should experience the highest quality of visual performance possible.

2/26/15


Barry Eiden OD, FAAOS. Barry Eiden, OD, FAAO
Medical Director, North Suburban Vision Consultants, Ltd.
NSCV Blog: www.nsvc.com/blog
President and Founder, International Keratoconus Academy of Eye Care Professionals

Cataract Surgery and Keratoconus

1/8/15

The eye works like a camera, specifically a digital camera. There is the front lens of the camera (cornea), the aperture (iris), the film (retina), and a cable to take the image to the brain (optic nerve). This “camera” also has an additional lens – the natural crystalline lens, which lies behind iris. This natural lens is flexible when we are young, allowing us to focus at distance then instantaneously up close. Around age 40-45, this natural lens starts to stiffen, necessitating the need for reading glasses for most people. This stiffening is the beginning of the aging process that eventually leads to formation of a cataract. We refer to the lens as a cataract when it becomes sufficiently cloudy to affect ones quality of vision.cataract surgery and keratoconus-Cataract diagram In general, cataract surgery is one of the safest and most successful of all surgeries performed. The basics of cataract surgery in eyes with keratoconus is very similar to non-keratoconic eyes.

Keratoconus (KC) affects this “camera” by causing the front lens (cornea) to bulge. This causes the optics to be distorted. In many cases, this can be corrected for with hard contact lenses (CL) or spectacles; in other cases a corneal transplant may be necessary. When it comes time for cataract surgery in the setting of KC, there are several factors that need to be considered.

Corneal Stability
The first thing to be considered is the stability of your cornea. In general, KC progresses more in your late teens to early twenties, and then stabilizes with age. A very exciting treatment for KC is collagen crosslinking. This treatment is meant to stiffen the cornea to prevent instability that is inherent to KC. This treatment promises to stop the progression of KC at a young age. Fortunately, with age, the cornea naturally crosslinks and stiffens, therefore when it comes time for cataract surgery, there is little chance of the progression of KC. Your doctor needs to choose the appropriate intraocular lens (IOL) to refocus your eye after surgery. Two of the most important factors in IOL selection are the length of your eye and the shape of your cornea. Long term CL wear can mold your cornea. It is important to assure that you stay out of your CLs long enough for your cornea to reach its natural shape. Depending on how long you have worn your CLs, it may take several months for the cornea to stabilize. This time can be challenging as your vision will be suboptimal (because you can’t wear CLs), and will be changing (as your cornea reaches its natural shape). When your cornea does stabilize, it is important to determine whether the topography (shape) is regular or irregular. This “regularity” is also known as astigmatism. If the astigmatism is regular, light is focused as a line – generally, this distortion can be fixed with glasses. However, if the astigmatism is irregular, light cannot be focused with glasses, and hard CLs are needed to provide optimal focusing. If you have had a corneal transplant, I generally recommend all your sutures to be removed to allow your new cornea to reach its natural shape.

IOL Selection
The second thing to be considered is the type of IOL. IOLs allow your doctor to refocus the optics of your eye after surgery. In many cases, the correct choice of IOL may decrease your dependence on glasses or CLs. There are several factors that are important when considering the correct IOL for a keratoconic patient. The amount and regularity of your astigmatism plays a very significant role in IOL selection. In general, there are four types of IOLs available in the US – monofocal, toric, pseudo-accomodating, and multifocal. In general I do not recommend multifocal IOLs in patients with KC. These IOLs allow for spectacle independence by spitting the light energy for distance and near, however, with an aberrated cornea (which is what happens in KC), these IOLs do not fare well. If there is a low amount of regular astigmatism or irregular astigmatism, your best bet is a monofocal IOL. This is the “standard” IOL that is covered by your health insurance. If you have higher amounts of astigmatism that your doctor determines is mostly regular, you may benefit from a toric (astigmatism-correcting) IOL. These IOLs can significant improve your uncorrected vision and really decrease your dependence on glasses. It is important to realize that monofocal and toric IOLs only correct vision at one distance. With a monofocal IOL you still can wear a CL to fine-tune your vision, however, with a toric IOL, in general you will need glasses for any residual error. There is a pseudo-accomodating toric IOL available, and this may be a good option if you are trying to decrease your dependence on glasses and correct some of your astigmatism. These IOLs are relatively new to the US market.

If You Had A Corneal Transplant
In the setting of a corneal transplant many of the same factors need to be considered – stability of the graft, choice of IOL, etc. In addition, the health of the graft has to be judged. Prior to cataract surgery in my patients with corneal transplants, I make sure to remove all of their sutures and give the cornea time to stabilize (just as if they were a CTL wearer). If you are a CL wearer, the same rule of being out of the TL until the topography is stable applies. The health of a transplant needs to be established prior to undergoing cataract surgery. The cornea has five main layers to it –cataract surgery and keratoconus-corneal structure the back layer (inside) is called the endothelium. This layer is responsible for “pumping” fluid out of the cornea, allowing it to stay clear. In all eyes there is a loss of endothelium cells with cataract surgery. I generally perform a “specular microscopy,” which allows me to visualize and quantify the corneal endothelium prior to surgery. This allows me to risk stratify you before your surgery. It is important to realize that corneal transplants have a lifespan and may have to be repeated in the future.

Keep in mind, there is some uncertainty in biometry (the process of selecting an IOL) in all eyes – this error can be higher in keratoconic eyes. This highlights why assuring stability is important. Equally important is picking the correct IOL for your situation. Also, keep in mind that I have discussed generalities in this article. Your individual case could be different. This is a conversation best left between you and your surgeon. In general, cataract surgery and keratoconus or a corneal transplant can be a very safe and effective way in restoring vision.

Sam Garg, MDSumit (Sam) Garg, MD
Interim Chair of Clinical Ophthalmology and Medical Director
Gavin Herbert Eye Institute at the University of California, Irvine

Breathing, Patience and Keratoconus

7/1/14

Besides hearing from eye care professionals and Discovery Eye Foundation staff, we also think it is important to hear from people with sight threatening eye diseases such as age-related macular degeneration, keratoconus, retinitis pigmentosa, etc. They can share their experiences with others that are newly diagnosed with eye disease, while providing insights to family members, friends and caregivers. What follows is the first of these occasional posts focusing on the experiences and insights gained from vision loss.

“The expression on my optometrist’s face was as if he was giving me a cancer sentence,” Jeanette Hasseman remembers. “I had never heard of keratoconus, but he told me it was an incurable vision disability. He said he was aware of some evolving technology, but he wanted to give me some time to absorb and research the disease.
Jeanette Hasseman - keratoconus
“When I went back three months later, he told me a about a cross-linking study that was going on not-too-far from here, but I hadn’t fully absorbed all the information I was reading yet,” she recalls. I did not understand — even though it was plainly stated in the information I was looking at — that once you lose some vision, you don’t get it back.

“I kept thinking, ‘OK, this certainly can be fixed,” so instead of getting cross-linking in July, I waited until December. I regret not acting on my doctor’s suggestion of getting in the study in July, because I lost a tremendous amount of vision by December.”

Hasseman was tested and qualified for the clinical trial in December and had epi-on cross-linking in both eyes in January 2013. “The topography scans show the KC progression has been halted,” she says. “I rejoice in that.”

While her vision seemed better shortly after the procedures, she was diagnosed one week after crosslinking with a “gouge” (4 mm corneal abrasion) in her left cornea that resulted in severe hazing. While the severity of the corneal hazing has decreased in the past year, she is waiting to find out if it is permanent. If so, she may need to have a corneal transplant at some point to restore any visual acuity.

A registered nurse, Hasseman finished her BSN degree two years ago at age 54 — just months before she was diagnosed with KC. The native Ohioan has since stopped working as a nurse, and more recently, she had to give up teaching and doing tatting — lace-making — a hobby she had enjoyed for decades.

Hasseman found the National Keratoconus Foundation (NKCF) when she first Googled “kerotoconus.” “KC-Link has been a great blessing,” she says. “I’ve downloaded information; I signed up for KC-Link and asked questions of Catherine [Warren, director of NKCF] and the moderating doctors. I found great support for my own spirit, as well as information on the latest technologies.

“When people ask questions on KC-Link, if I can relate, I answer. Just the other day, someone who was just diagnosed asked, ‘Well, what should I do?’ I wrote: ‘First thing is: Breathe. Second thing is: Ask for information from your eye doctor and ask who is the best corneal specialist in your area who is really good for keratoconus. Most of all: Be patient.’

“It’s really hard to lose your vision. Even in your own heart, you can feel isolated. KC-Link gives you a body of other people who totally understand what you’re thinking, what you’re feeling, what frustrates you. There is so much advice you can get on KC-Link regarding contacts, how to keep eyes moist, how to handle low-light driving, what type of e-reader works best for people with keratoconus — you cannot exhaust the information that is shared; you cannot exhaust the different emotions that are shared.”

Jeanette HassemanJeanette Hasseman
Keratoconus Advocate