Experiences with a Silicone Hydrogel Lens
practitioners share how incorporating a silicone hydrogel lens into their respective
practices has benefited many of their patients.
By Gregg Russell, OD, FAAO
introduction of hyper-Dk/t silicone hydrogel lenses has created a change in the
way eyecare professionals present contact lens options. Many practitioners now say
that silicone hydrogel lenses aren't just for continuous wear. In fact, currently
most silicone hydrogel lenses are prescribed primarily for daily wear.
The lotrafilcon B material of CIBA Vision's
O2Optix lens contains 33 percent water with a permanent surface treatment
to assure surface wettability for comfort and resistance to protein deposits, according
to the manufacturer. CIBA Vision also says O2Optix provides 62 percent
greater oxygen transmissibility than does Acuvue Advance (Vistakon) and more than
five times the oxygen of Acuvue 2. O2Optix is available in an 8.6mm base
curve in spherical powers from +6.00D to –8.00D in 0.25D steps, and from
–8.50D to –10.00D in 0.50D steps.
find out how O2Optix is changing the way practitioners approach contact
lenses and how their patients have responded I spoke with three optometrists
about the lens.
It's the Oxygen
Hands down, the hyper-oxygen transmissibility
is the favorite lens feature for these eyecare practitioners. Muriel Schornack,
OD, of the Mayo Clinic in Rochester, MN, provides her patients with a corneal physiology
lesson. She tells them, "The cornea is an avascular system. If it doesn't receive
enough oxygen, bad things can happen." Most patients don't consider that a contact
lens serves as a barrier between the cornea and oxygen. "If you point out that they're
putting plastic on tissue that's living, it gets their attention," Dr. Schornack
While Dr. Schornack has heard from many patients
that the lenses are more comfortable, to her that's not the selling point. "I want
patients to leave with a high-oxygen-transmissible lens. I tell them, 'If this lens
works for you, then this is what I want you to wear.'"
Chris T. Miller, OD, from Evanston,
IL, shows patients a chart that compares the 138 Dk/t of O2Optix to the
low-Dk/t values of HEMA two-week replacement lenses. "Patients are usually surprised
because they haven't heard of oxygen transmissibility. I tell them, especially if
they wear their contact lenses many hours each day, that this is the best lens for
them." Dr. Miller's presentation convinces patients it's a healthy option; a one-week
trial has convinced most of his patients that it's also a more comfortable lens,
In my practice, I use a down-to-earth
analogy that all patients understand. I tell patients, "Wearing a contact lens
that provides higher oxygen levels to the eye compared to standard two-week disposable
lenses is like wearing 100 percent cotton on a high humidity day vs. wearing 100
Expanded Patient Pool
Douglas Weberling, OD, of Bristol, VA, says a
lens with greater oxygen transmissibility translates into a greater candidate pool.
"I've been able to maintain more patients who complain of dryness symptoms and who
are aged 45 and above. Patients who complain that their eyes feel dry after a day
of computer use have also loved the lens," he says. He's heard from patients who
are ecstatic because they can now comfortably wear their lenses for 14 hours a day.
"With low-Dk/t HEMA lenses, these same patients were removing their lenses after
just a few hours," he says. "When I provide patients with a trial pair of O2Optix,
I send them out with this directive: Compare how these lenses feel at 4 pm.
That's when patients really start to notice the difference," he says.
Patients who become frustrated with contact
lenses because of dryness, itching and irritated or red eyes are on the brink of
becoming contact lens dropouts. That's tough for any practice on several fronts:
not only might they drop out of contact lenses, they could drop out of the practice
entirely. Not to mention that contact lens patients are generally more compliant
in terms of returning for their annual exams than are spectacle patients.
By promoting a change to the O2Optix
lens, Dr. Weberling has found that his formerly frustrated patients are now solidly
back in the contact lens-wearing column. To boot, they have become enthusiastic
boosters of his practice.
The Price Differential
When CIBA first introduced Night & Day, its
175-Dk/t silicone hydrogel approved for up to 30 nights of continuous wear, patients
who wanted continuous vision saw the value in the premium price associated with
its new technology. With O2Optix, the price differential compared to
low-Dk/t lenses is negligible in fact, it's non-existent when patients redeem
the manufacturer's rebate, Dr. Weberling says.
So for patients who may have expressed interest
in occasional overnight wear or who noted some symptoms of corneal oxygen deficiency
but weren't ready to switch into continuous wear, the O2Optix lens may
provide the benefits they want at a comparable price, Dr. Weberling says.
Lens Handling and Wearing Schedule
Dr. Schornack selects this lens for her young
patients. "These lenses are easy to handle," she says. "Handling ease as
well as oxygen transmissibility are benefits to first-time contact lens wearers.
If any of my patients have trouble handling other two-week replacement lenses, I
recommend a switch to O2Optix," she adds.
Dr. Schornack recommends daily wear for most
O2Optix patients. But if they choose to occasionally sleep in their lenses,
she feels comfortable because the lenses exceed the 125 Dk/t level recommended for
no stromal anoxia during overnight wear.
Dr. Weberling, however, is an active
proponent of extended and continuous wear. In his practice, Night & Day
is a big success. O2Optix, with its Food and Drug Administration approval
for up to six nights of extended wear, has generated interest in his patients who
are interested in occasional overnight wear. Dr. Weberling emphasizes the risk factors
for infection from extended wear to encourage excellent hygiene and compliance.
He makes sure patients know that they shouldn't continue to wear the same lenses
without proper disinfection during and after an illness and that they
shouldn't swim while wearing the lenses. For patients who work or live in a smoke-filled
environment, he recommends daily wear or even occasional contact lens wear.
Don't Accept the Status Quo
Eyes get red
at end of day
1. Symptoms related to corneal hypoxia and percentage of patients who experience
It's simple to introduce O2Optix to
new contact lens wearers by telling them it's the newest, most advanced contact
lens technology to come on the market. After hearing that, why would a patient ask
you to prescribe an older material? "We tend to prescribe O2Optix as
an alternative to eyeglasses that's more convenient and equally effective," Dr.
Yet among patients who've worn contact lenses
for years, many have come to accept their daily nuisances and discomforts. "Such
patients have no basis for comparison," says Dr. Schornack. That's why it's up to
practitioners to ask discerning questions that yield more information than a simple
yes or no question would.
I recommend questions that specifically
address dryness, compliance and overall visual quality. For example, to assess dryness,
I ask, "How does your end-of-day comfort compare to the beginning of the day?" Don't
simply depend on tear performance tests done in the office because they don't always
yield reliable answers, nor do they necessarily provide information about the source
of problems with visual performance in contact lenses.
To learn about patients' lens wearing
habits, ask open-ended questions such as, "How old is your current pair of lenses?"
"How frequently do you sleep in your lenses?" and "How often do you dispose of
your lenses?" Document the answers in the patient's chart, especially if he's doing
things contrary to your previous instructions. This information can serve as an
important segue to explaining other contact lens options.
To better gauge a patient's overall
satisfaction with his quality of vision, add a subjective question such as, "Is
your vision just as good at the end of the day vs. the beginning of the day?" or
"How is your night vision?" This will provide important information.
Create a Buzz
These practitioners share an enthusiasm for
new technology and patients perceive that. Dr. Weberling says, "If I offered
patients the same lenses year in and year out, they might as well go elsewhere and
price shop. Offering new products has encouraged my patients fill their contact
lens prescriptions here." Dr. Weberling also says that when he can reintroduce successful
contact lens wear to a patient who dropped out of contact lenses years ago, that
Schornack says, "For patients who can't or won't change their two-week wearing schedule,
these lenses mean that we can offer a healthy lens option. From a professional standpoint,
I liken O2Optix to Seldane, the first-generation non-sedating antihistamine.
Before that came out, allergy sufferers had the choice of not breathing well or
breathing well, but falling asleep. When the new drug came out, practitioners quickly
started prescribing it. When HEMA was the best we had, it sufficed. But silicone
hydrogel lenses help to decrease the physiologic impact of hypoxia on the cornea."
Other practitioners share Dr.
Schornack's view that to continue prescribing low-Dk/t contact lenses may no longer
be the best option for some patients. And in doing well for the patient, these clinicians
have found that their practices and professional reputations benefit. CLS
What is Corneal Oxygen Deficiency?
Some of the symptoms potentially related to corneal oxygen deficiency
include: red eyes, blurry/hazy vision, eyes that feel irritated when wearing contact
lenses, eyes that feel uncomfortable at end of day and lens-related dryness (Figure
1). A primary cause of corneal oxygen deficiency is wearing low-oxygen-transmissible
contact lenses. In fact, 94 percent of contact lens wearers reported experiencing
at least one or more of these symptoms.
Dr. Russell is in practice at the Marietta
Eye Clinic. His clinical research interests are in dry eye, aberration control,
presbyopia and contact lens design.
Contact Lens Spectrum, Issue: December 2005