ICRS: Intracorneal ring segments or INTACS
with ring segments
Ring segments are micro-thin plastic rings that are
inserted into the peripheral cornea. These rings mechanically
flatten the central cornea to correct nearsightedness.
Currently, up to -3.00 diopters of nearsightedness can
be corrected with INTACS. Astigmatism cannot currently
be treated. Research is underway to expand the range
of what the rings can correct. The rings are inert and
are meant to be left in place permanently.
One advantage of the rings is that they are removable,
should the patient find they are unsatisfactory. The
rings also offer the possibility of allowing a person
to remove the rings at a later date, and switch to technology
not-presently available that may better suit the person's
Most often, the patient's prescription goes back to
what it was before the rings were inserted. Visual recovery
is a bit slower than with LASIK, but excellent visual
results have been obtained. Theoretically, the inserts
leave the cornea in its natural "prolate"
shape, perhaps giving patients better quality vision
than current laser vision correction procedures provide.
It may be safer than LASIK because no incision crosses
the center of the cornea.