CK,
or Conductive Keratoplasty, was developed by the Refractec company in
California. Refractec designed the Viewpoint CK System to deliver radiofrequency
(RF) energy to reshape the cornea in the treatment of longsight and
presbyopia, the need for reading glasses.
The idea to steepen the cornea to treat longsight has
been around for some time. The difficulty has been developing a method
of delivering a very small, controlled amount of energy to the edge of
the cornea at the right depth, sufficient to raise the temperature by
just the right amount. This warming causes a contraction of collagen fibres, like a
belt being tightened a couple of notches. The belt tightening at the periphery
of the cornea causes steepening of the central part through which you
see.
Initial treatments in the late 1970s using a hot wire didn't
prove to be successful or predictable in their effect. Two different
methods of using laser energy have been tried, without long lasting
success. The most recent was the Hyperion LTK laser developed by the
Sunrise Corporation. The effect of LTK proved to be transient in many
patients.
Fortunately, the problems with regression of the treatment effect
have been overcome by Refractec's Viewpoint CK System. The secret is in
using a super fine tip to apply RF energy equally through the body
of the cornea, and not predominantly to the surface as with previous
approaches. RF energy has been used in various fields of medicine since
the 1950s and is a safe and established technology.
FDA studies for the treatment of longsight are now two
years on, and show excellent stability of effect. Dr. Jose Guell of
Spain, one of Refractec's investigators for the CK system, has patients
still stable after almost four years.
