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Q: CK for improved nearsightedness ( Answered 4 out of 5 stars,   1 Comment )
Subject: CK for improved nearsightedness
Category: Health
Asked by: bridgewalker-ga
List Price: $50.00
Posted: 03 Oct 2005 08:35 PDT
Expires: 02 Nov 2005 07:35 PST
Question ID: 575763
I'm thinking of having CK done to my eyes.  I don't want to carry
readers around my neck and I hate having to retrieve them whenever I
need to read anything in poor light or under about 12 point type.
I'm interested in knowing 2 things: What kind of experience have
people had with the technique and is it advisable for a 72 year old
male to consider this.
Subject: Re: CK for improved nearsightedness
Answered By: crabcakes-ga on 03 Oct 2005 13:47 PDT
Rated:4 out of 5 stars
Hello Bridgewalker,

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   It appears that CK (Conductive keratoplasty) is able to restore
your vision to the point where you began to notice your arms were
getting shorter!  Sometimes CK is referred to as a ?temporary?
solution, because as you age, your vision will again weaken. The
surgery itself is permanent, but the aging process of farsightedness
will continue. According to the site below,  you can return to your
normal activities 1-3 days after CK surgery.

CK does not use lasers to correct the shape of the cornea, but instead
uses radio frequency (RF) to treat farsightedness (hyperopia).
Monovison therapy (On eye for distance, one for close up) has been the
standard, but some ophthalmologists are
performing the blended vision technique. (More below)

The best candidates for CK surgery are people over 40, and who have
had no drastic vision changes in the past year. People with diabetes,
glaucoma, keratoconus, herpes of the eye, pacemakers, heart disease,
and people with autoimmune diseases are excluded from CK surgery.

I?ve found that Ck is recommended for persons over 40, but have found
no upper age limits. Your ophthalmologist is the one who can determine
if you are a good candidate for this surgery, based on not only your
age, but your measure of vision, eye health, and any medical
conditions you may have. It also appears that patients are generally
pleased with their CK surgery. In one study, the oldest participant
was 71 years old.

?Treatment of hyperopia with CK produces safe and effective results in
a large majority of patients. As a nonablative, nonincisional
procedure, CK does not invade the central cornea; compromise the
integrity or structure of the cornea; or cause dry eye, flap-related
complications, or central haze. In addition, CK can be performed in
the office setting with only topical anesthesia, is technically easier
to perform than other hyperopic procedures, and involves use of a
portable unit that is much less expensive than most other refractive
surgery platforms.

When performed in one eye to improve near vision, CK improved
binocular vision so that 89% saw 20/32 uncorrected distance as well as
J3 near. CK causes minimal to no compromise to distance vision
binocularly and does not reduce contrast sensitivity or depth
perception (which are reduced after monovision LASIK). CK appears to
be very safe and effective in producing functional visual acuity in
presbyopic eyes. Patients report a high rate of patient satisfaction.?

?If you have presbyopia, one of our doctors may recommend ?blended
vision?. Unlike ?monovision?, (where one eye is treated for near
vision, leaving the untreated eye for distance vision), blended vision
improves your ability to focus on near objects without sacrificing all
of your distance vision in the treated eye. This makes it easier for
you to adjust to the two separate images. If you have not tolerated
monovision treatments in the past, blended vision may be a better

?The vast majority of patients do not need corrective lenses of any
kind after the CK procedure. However, depending on your age and the
type of refractive disorder you have, you may need additional vision
correction (surgery, reading glasses, or bifocals) at some point. This
is because your eyes continue to change as you age.?

?The best CK patient is over 45 years old, and has good distance
vision without use of eyeglasses. Patients interested in CK typically
hate to use reading glasses.?

This site explains the difference in presbyopia and hyperopia:
?Hyperopia can be present in individuals of any age. People with
hyperopia have eyeballs that are too short or corneas that are too
flat. When light enters a hyperopic eyeball, it is focused behind the
retina instead of directly on the retina where light must be directed
for normal vision. This causes difficulty in seeing near objects
clearly. CK, as well as laser procedures such as LASIK (Laser in-Situ
Keratomileusis?a refractive procedure that involves cutting the
cornea), reshape the cornea to fix the focusing problems.

Presbyopia, on the other hand, is the gradual loss of flexibility of
the lens of the eye, which also causes difficulty in focusing on items
up close. This begins to be noticeable in most people at about age 40
and progresses until the lens has no more flexibility?generally, at
about age 70. Surgical techniques that change the shape of the cornea,
including LASIK and CK, can not directly ?cure? presbyopia since the
problem is not the cornea but the loss of lens flexibility.

 However, with CK we try to go for ?blended vision? to correct
presbyopia. This approach can be used to improve visual comfort in
people with presbyopia and allow them avoid having to wear reading
glasses. In this technique one eye is used for far-away vision and one
for near vision, despite the loss of lens flexibility. Change in
refraction can be done with CK as well as LASIK. If the person is
under the age of 70, the lens will continue to lose flexibility after
the procedure and he or she may require future surgical modification
or reading glasses. CK is not used for nearsightedness, but LASIK is.
And of course, many people choose to wear contact lenses to correct
nearsightedness. These individuals can also have a blended vision

?For most farsighted patients, the CK procedure makes it possible to
eliminate the need to wear reading glasses. In clinical trials, nearly
95 percent of patients with low to moderate ranges of hyperopia
achieved normal or near-normal vision after CK. The FDA has approved
CK for the treatment of hyperopia between +0.75 and +3.25 diopters.
(The diopter is a measure of refractive error.)?

?Farsightedness (hyperopia) is often confused with presbyopia, which
is a normal development of the aging process. Presbyopia occurs when
the lens inside the eye loses flexibility, thereby preventing accurate
focusing on nearby objects. This condition is common in individuals by
the age of 40 years, and all persons older than 50 years experience
presbyopia. People with this condition may experience eye
strain/fatigue when reading in poor lighting conditions or at the end
of the day, have trouble (slow) in changing focus from distance to
near, or need to constantly reposition (move away) reading material in
an attempt to find the correct focus.
CK indications for use, as approved by the FDA, are as follows: 
·	CK treatment for the reduction of spherical hyperopia in the range
of +0.75 D to +3.25 D of cycloplegic spherical hyperopia, with -0.75 D
or less of refractive astigmatism, yielding +0.75 D to +3.00 D
cycloplegic spherical equivalent
·	CK treatment in patients with less than or equal to 0.50 D
difference between preoperative manifest and cycloplegic refractions
·	CK treatment in patients aged 40 years and older?

Complications and adverse events 
·	Adverse events to occur in no more than 5% of eyes; any single
adverse event to occur in <1% of eyes
·	Recurrent corneal erosions in both eyes of 1 patient (<1%), resolved by 3 months 
·	Foreign body sensation in 1 eye of 1 patient (<1%), reported at 9
months and resolved by 12 months
·	Pain in both eyes of 1 patient (<1%), reported at 3 months and
resolved by 6 months
·	Double/ghost images in 13 eyes of 9 patients (3%), complaint
resolved in most eyes (10 out of 13 eyes)
·	Other complications occurring at a rate of <1% include blepharitis,
external hordeolum, viral conjunctivitis, allergic conjunctivitis,
bacterial conjunctivitis, meibomianitis, subconjunctival hemorrhage,
central striae, central stromal defects, lash loss, ecchymosis, blurry
vision, starbursts, headaches, film over eye, glare, halos, and light

?Our proprietary ViewPoint® CK System is the first and only
FDA-approved technology for the temporary improvement of near vision
in patients who want to reduce their dependence on reading glasses.
NearVision  CK  (Conductive Keratoplasty ) offers baby boomer patients
a safe, simple alternative to laser procedures?

The Procedure

?CK is performed using a small probe, thinner than a strand of hair,
that releases radiofrequency energy. The probe is applied in a
circular pattern on the outer cornea (front window of the eye) to
shrink small areas of corneal tissue. This circular pattern creates a
constrictive band (like the tightening of a belt), increasing the
overall curvature of the cornea to treat farsightedness.

The procedure, which takes about three minutes, is done in the
doctor's office with only topical anesthesia (eye drops). No tissue is
removed, no flap is made as in LASIK, and the central cornea is left

?The operation is performed as an outpatient procedure under topical
anesthetic under a microscope. Anesthetic (numbing) eye drops are
placed in the eye immediately prior to surgery in order to minimize
pain during the procedure.  In some cases, a mild sedative pill may be
administered to reduce apprehension prior to surgery.  The eyelid is
cleansed and held open using a special instrument.
A pattern is marked on the cornea.  Then the probe is applied to the
peripheral cornea in a set grid. Each treatment spot takes a few
seconds as the probe painlessly heats the cornea to 65 degrees
centigrade. The pattern of gentle burns to the peripheral cornea may
be visible for a while as white spots.

For the first few days after treatment minor surface irritation, glare
sensitivity and over correction are common.  Distance vision may be
slightly blurred and the eye may be a little irritable.?

?Although the vast majority of patients report markedly improved
uncorrected vision quite soon after CK, an individual patient?s best
vision may not be realized for several weeks or months later. 
Patients who do not experience full correction may opt to wear
glasses, contact lenses or could possibly have additional refractive
surgery (either CK or other procedures).  These enhancements
(re-operation of CK or other procedures) for residual refractive
errors has been less than 10%.  Generally, re-operation will not be
performed for at least three months following the original procedures.
The purpose of CK is to reduce your refractive error such that you are
visually comfortable without glasses.  We cannot, however, guarantee
that you will not have to wear glasses or contact lenses either some
or all of the time to achieve your best corrected vision.  Even if
your uncorrected vision is significantly better than it was before
surgery, you may still require glasses or contact lenses either full
or part time in order to see well for distance tasks (such as driving
or golf).  Additionally, you may, depending on your age, need to wear
reading glasses after LASIK.  This is still true if you choose to have
monovision correction.?

??A probe?smaller than a strand of human hair?applies heat in a
circular pattern of spots in the outer cornea to shrink small areas of
collagen. Like tightening a belt, it steepens the cornea?s central

The procedure takes less than five minutes and is done in-office under topical
anesthesia (eye drops). There is no cutting or removal of tissue involved. When
correcting presbyopia, usually one eye is treated? leaving the
dominant eye alone for distance, and reshaping the nondominant eye to
give it a near focus.

Dr. Hamilton usually has his patients wear a contact lens for several days in the
nondominant eye first to simulate the effects of conductive keratoplasty prior to
administering the procedure. An ideal candidate for this procedure is over 40 years
old, sees well at a distance without glasses, and wants to reduce dependence on
reading glasses. Conductive keratoplasty has been used previously for
but was recently approved by the Food and Drug Administration for
presbyopia.? (This is a slow loading site)

?In 233 patients, 401 eyes were treated with a mean hyperopia of 1.82
+/- 0.6 diopters. At 24 months, 52% of eyes achieved 6/6 vision or
better unaided and 93% had 6/12 or better. Refractive stability was
noted between 12 and 24 months follow-up. Overall, the procedure was
safe, and patients were satisfied: 91% felt their vision was
moderately to greatly improved, and 82% were satisfied or very
satisfied. Some retreatments were necessary. Dr. McDonald (who
declared a financial interest in this subject matter) concluded that
CK seems to be effective, safe, stable, and can spare the visual

?What are the risks and side effects of Conductive Keratoplasty?

Because CK is minimally invasive the procedure has shown very little
risk and almost no side effects. During the first 24-48 hours after
surgery, you may experience tearing and some discomfort, including a
foreign-body sensation in the eyes. You may also experience initial
slight overcorrection of your vision, which stabilizes during the
following weeks. However, because CK doesn't cut or remove tissue,
many of the side effects associated with other vision correction
procedures have not been seen with CK.

Are there restrictions after having CK?

As with any vision correction procedure where the cornea is altered,
certain precautions should be taken. After the CK procedure, patients
should avoid getting contaminated water in their eyes for at least one
week. This includes water from swimming pools, spas, lakes, and the
ocean. When showering or taking baths, patients should keep their eyes
closed in order to avoid getting soap and dirty water into their eyes.
When exercising, sweat should be kept out of the eyes for at least a
week after surgery. Also, patients should avoid rubbing the eyes
vigorously for two weeks following the procedure.?

?For the risk-averse, conductive keratoplasty is the procedure of
choice. When people over age 40 were asked if they would consider an
elective procedure to reduce their dependence on glasses, a full 42
percent ranked CK their number-one choice, citing its non-invasive
method and safety as the primary reasons for their preference. Prior
to CK, few people between the ages of 40 to 60 have even considered
vision treatment surgery, as they tend to be more conservative and
risk-averse than their younger counterparts.?

Main Complications:

? Fluctuation in vision (only temporary)
? Under-correction (corrected with enhancement)
? Over-correction (rare, may require temporary glasses)
? Sensitivity to light (temporary during first month)

?What are the risks?
Because CK is minimally invasive, the procedure has exhibited very
minimal risks. You may experience initial slight over-correction of
your vision, which stabilizes during the following weeks. However,
because CK doesn?t cut or remove tissue, many of the side effects
associated with other vision treatment procedures have not been
observed with CK.?

?NearVision CK is a non-laser procedure that uses controlled radio
waves to improve near vision. Rather than removing tissue with a
laser, NearVision CK reshapes the cornea using an entirely different
method: the application of low-level radiofrequency (RF) energy
applied in a circular pattern on the outer cornea to shrink small
areas of collagen in the corneal tissue. This circular pattern acts
like a belt tightening around the outer cornea to increase its overall
curvature and bring life's details back into focus. The procedure,
which takes less than three minutes, is done in-office with only
topical "eye-drop" anesthesia.?

? (Dr. Knobbe): Okay. How does the surgeon control the
amount or degree of treatment, and is this based primarily on the
preoperative refractive error?
Dr. Marguerite McDonald: Yes, and there is a nomogram that is used to
determine the number of spots that should be placed with more spots
for more farsightedness. Even though CK is (FDA) approved all the way
up 3 diopters, between +2.50 and +3.00 diopters the enhancement rate
starts to go up so much that most ophthalmologists are not pushing it
to its extreme limit anymore. (Dr. Knobbe): Okay. Are you using CK for low hyperopes,
such as +1.00?
Dr. Marguerite McDonald: All the time. I routinely go up to +2.50 with it. (Dr. Knobbe): Does CK cause any weakening of the cornea
that might result in corneal ectasia or abnormal bulging of the
Dr. Marguerite McDonald: Not at all. There is no tissue removed so the
cornea remains structurally intact. (Dr. Knobbe): How long does the treatment take?
Dr. Marguerite McDonald: Well, with intraoperative titration of
effect, about ten to fifteen minutes per eye.?

Additional Information
?Marguerite B. McDonald, MD, a strong advocate of CK, noted that ?in
patients between +2.5 D and +3 D, the enhancement rate goes up with
CK, and many need to be brought back for a touch-up. While some
doctors have decided to stay away from the procedure in these
patients, I will sometimes go for +3 D?for instance, in dry eye
patients who would not do well with LASIK?and inform the patient that
there is a somewhat increased chance of needing an enhancement.?

In contrast, Ernest W. Kornmehl, MD, will not perform the procedure on
any patient who is +3 D and would prefer to perform LASIK in the vast
majority of patients under +3 D. Dr. Kornmehl states that he is ?not
currently recommending conductive keratoplasty because the FDA has
only approved it as a temporary procedure for mild to moderate
farsightedness and only 50 percent of the patients in the study were
very satisfied. In addition, the long-term effects of radio frequency
energy on the eye are not known at this time.? Hyperopic patients
should have the highest satisfaction rate of all refractive patients,
Dr. Kornmehl said, ?and a rate of only 50 percent being ?very
satisfied? is low.?

?Preferred Candidates 
Who is the ultimate candidate for hyperopic CK? Dr. Manche provided
the patient profile: Individuals in their 50s or 60s, with dry eyes
and low levels of hyperopia (+1, +1.5 and +1.75). ?Also, someone who
does not have to be back to normal vision the next day,? he said.
?Consequently, a person who is retired would be a better candidate
than one who is a busy CEO of a company. He or she would benefit from

High expectations of refractive surgery make patient education a must.
As Dr. Manche put it, ?Most patients who seek LASIK have a certain
mindset and want instant results. Yet with hyperopic CK, postoperative
day 1 and day 2 are not very sharp. Consequently, it is imperative
that clinicians reeducate their patients on their expectations so that
they are not disappointed immediately following surgery.?

A second challenge for those who perform hyperopic CK may lie in
marketing the technique. Dr. McDonald pointed out that the ?target
audience? for this technique?people in their late 40s to 60s?tend to
be skeptical of lasers. ?While younger people have infinite faith in
lasers, older people are afraid,? she said.

Dr. McDonald cited a recent study in which 70 percent of the older
population had never considered laser surgery, 30 percent had thought
about it and 2 percent actually underwent a laser procedure.?


I hope thi shas helped you!

If any part of my answer is unclear, I will be happy to offer further
assistance before you rate this answer. Simply request an Answer
Clarification and I will respond as soon as possible.

Sincerely, Crabcakes

Search Terms

Conductive Keratoplasty
Conductive Keratoplasty + risks
Conductive Keratoplasty + elderly
Conductive Keratoplasty + patient satisfaction
bridgewalker-ga rated this answer:4 out of 5 stars

Subject: Re: CK for improved nearsightedness
From: bhanee-ga on 05 Oct 2005 06:28 PDT
the answer to this question is simply marvellous and well researched.
crabcakes deserves congrats. nothing more to add from my side.

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