Refractive Lens Surgery

94 S.J. Dell
Fig. 10.8. Small capsulorrhexis helps ensure correct
posterior vaulting of the Crystalens. A capsulorrhexis
that is too large can allow anterior vaulting
of the lens, while one that is too small
complicates cortical removal and lens implantation,
and tends to provoke an intense fibrotic reaction
of the capsule
ens are posteriorly vaulted in the correct position
(Fig. 10.8). A capsulorrhexis that is too
large can allow anterior vaulting of the lens,
while one that is too small can lead to an overly
aggressive fibrotic response of the posterior
capsule as many more anterior lens epithelial
cells are left in place. Very small
capsulorrhexes have the added disadvantages
of complicating cortical removal and delivery
of the trailing plate into the capsular bag. Additionally,
a very small capsulorrhexis may
dampen accommodative movement of the
optic by trapping the Crystalens in a fibrotic
cocoon formed by fusion of the anterior and
posterior leaves of the capsule. Surprisingly,
proper capsulorrhexis sizing has been one of
the more challenging aspects of the first few
cases of surgeons transitioning to this lens.
In general, the Crystalens provides excellent
centration as a result of the polyimide
loops at the termination of the plate haptics.
Fixation of the polyimide loops occurs relatively
early in the postoperative period and
exchanging or repositioning the Crystalens
can be difficult after approximately 4 weeks.
The Crystalens cannot be dialed or rotated in
a traditional fashion, as the four polyimide
Fig. 10.9. Crystalens that has become stuck in an
anteriorly vaulted position due to a wound leak or
sudden anterior chamber decompression. Striae
are typically visible in the posterior capsule corresponding
to the long axis of the lens. Surgical repositioning
is required
loops engage the peripheral posterior capsule.
However, the lens can easily be rotated
by centripetally pulling on the optic and allowing
it to rotate in short “jumps” with each
such maneuver.
A watertight wound closure is essential
with the Crystalens, as the implant is susceptible
to a unique complication from a leaking
wound. Standard IOLs may tolerate a wound
leak with only transient shallowing of the anterior
chamber, which re-deepens as the
wound eventually seals. However, the architecture
of the Crystalens creates a different
situation. As a result of the extremely flexible
plate haptics,a wound leak can allow the Crystalens
to vault anteriorly, and the lens can become
stuck in this position. This phenomenon
requires surgical repositioning of the lens
(Fig. 10.9). The Crystalens is designed to be
implanted without folding. Typically, the lens
can be implanted through an incision of approximately
3.2 mm as it auto-conforms to the
incision tunnel architecture. As uniplanar
clear corneal incisions are prone to leakage in
the early postoperative period, their use is discouraged
with the Crystalens [15, 16]. Miotics
are not used at the time of surgery.