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Crystalens is the brand name of an intraocular lens (IOL) that is designed to provide distance,
midrange, and near vision for pseudophakic patients. Crystalens is commonly used in cataract patients, but may also be appropriate for patients
considering RLE. Crystalens may be an appropriate alternative to monovision for some patients.
Presbyopia and Accommodation
As we mature, the natural crystalline lens in the eye expands, firms, and loses its ability
to accommodate from distance to midrange to near vision. This normal
condition is known as presbyopia and develops in most people in between 40 and 60
years of age. It is first noticeable when it becomes difficult to
read items close to you, often requiring reading glasses, bifocals, or trifocals.
Cataract Surgery & RLE
During surgery for cataracts or RLE, the crystalline lens of
the eye is removed and replaced with an artificial IOL. A conventional
IOL is commonly focused for distance vision only. It does not change
from distance to near vision, and reading glasses or monovision
are required for the patient to be able to see items at all distances.
The purpose of the Crystalens is to provide cataract and RLE patients
with the ability to accommodate.
Vaulting for Focus
The Crystalens accommodating IOL is specially designed so it
may move forward and backward within the eye in response to flexing
of the same muscles that manipulated the crystalline lens for accommodation.
This is sometimes called pseudoaccommodation, but is actually real
accommodation with an artificial lens. The vaulting movement changes
the focal point and may allow a patient to accommodate. This accommodation
may reduce the need for reading glasses, bifocals, or trifocals,
and does not require any special exercise or thought process on
the part of the patient. Accommodation with a Crystalens is the
same as accommodation with a natural lens. Two and three year follow
data indicates that the pseudoaccommodation of the Crystalens does
not significantly diminish with time.
Measurable Improvement
In the FDA clinical trials it was found that a vast majority, but not
all, patients implanted with a Crystalens accommodating IOL achieved
a measurable improvement in accommodation. It was also indicated
that the Crystalens provided vision quality equal to or better than
a conventional IOL. It would appear that there is no significant
downside to the Crystalens accommodating IOL, and the high probability
of functional accommodation is most assuredly an upside.
Limited Improvement
Despite all the apparent good news, do not expect too much from
an accommodating IOL. Accommodation will not be restored to the
level of function you had when you were 30. For a few, accommodation
will actually be less after a Crystalens, but will be more than
with a conventional IOL. Keep expectations reasonable.
Patient Selection
The Crystalens is not for everybody. If the natural ciliary muscle contractions are weak or the zonules are damaged, the Crystalens IOL may not accommodate even if implanted
correctly. If the ciliary muscle or zonules do not function, a pseudoaccommodating
IOL essentially becomes a conventional IOL. If the patient's pupils
do not chemically dilate adequately, the doctor will be positioning
the haptics around a blind corner, but if the patient's pupils naturally
dilate too large, the Crystalens may induced glare in low light
environments. It is possible that a posterior capsule opacification
may occur, but a quick laser procedure usually takes care of this
problem. The recovery time for a Crystalens may be slightly longer
than with a conventional IOL. Also, the cost of the Crystalens is
significantly more than a conventional IOL, and some insurance plans
may not pay for all or part of the surgery if the patient elects
to use a high technology Crystalens.
Implanting the Crystalens is more challenging than implanting
a conventional IOL. It will be important to seek the care of a doctor
with a reasonable amount of practical knowledge of RLE or cataract
surgery and the Crystalens accommodating IOL. You may find that
a cataract doctor has more experience with IOL implantation than
a Lasik doctor.
Medicare Allowed
Thanks to a change in Medicare policy, patients who need cataract
surgery and are covered by Medicare may now elect to purchase the
Crystalens at an additional cost over a conventional IOL. Before
this policy change, Medicare's restrictions made it nearly impossible
for a patient to acquire a Crystalens IOL. Now the patient may elect
to pay the additional fees for the doctor, facility, and lens. See Crystalens
Medicare Policy Details.
Improvement Over Time
Lastly, if you have the Crystalens, be patient. It takes time
for your brain and eye muscles to become accustomed to the new possibilities
afforded with the Crystalens. Although accommodation may be immediate,
expect the changes to be slow with improvement in real function
over the first year. For more information, visit the FDA or the Crystalens. Crystalens is sometimes misspelled
as CrystaLens, Crystal Lens, Crystal-Lens, or Crysta-Lens.
Looking For Best Lasik Surgeon?
If you are ready to choose a doctor to be evaluated for conventional
or custom wavefront Lasik, Bladeless Lasik, PRK, or any refractive surgery procedure, we recommend you consider a doctor who has been evaluated and certified by the USAEyes nonprofit organization.
Locate a USAEyes Evaluated & Certified Lasik Doctor.
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