Refractive Lens Surgery

Fig. 17.8. A laser interferogram (left) demonstrates
a 20-D LAL in vitro. If a –1.50-D postoperative
error resulted, the lens could be irradiated to
reduce the power and achieve emmetropia (cen-
tics. If intolerant, the multifocality could be
reversed and a trial of monovision could be
induced. Once the desired refractive status
was achieved, the LAL could then be locked in
permanently. This would give patients the option
of experimenting with different refractive
optics and deciding in situ which was
best for them.
To date, the potential drawbacks of refractive
lens exchange have included the risk of
endophthalmitis, retinal detachment, and the
inability to guarantee emmetropia in these
highly demanding patients [11, 12]. Hopes of
reducing or eliminating the risks of endophthalmitis
are now being boosted by the introduction
of newer fourth-generation fluoroquinolone
antibiotics, while the issue of lens
power accuracy can now be potentially solved
with the adjustment capabilities of the LAL
[13].
Retinal detachment following cataract and
refractive lens surgery is more common in
high myopes but can occur in any patient. Detachments
usually occur secondary to tears
from posterior vitreous detachments that develop
by removing the space-occupying crystalline
lens and replacing it with a thin
pseudophakic IOL. Calhoun Vision has researched
an injectable silicone polymer with
the same light-adjustable properties as the
LAL, which offers the possibility of reducing
Chapter 17 The Light-Adjustable Lens 167
ter). This could then be followed by creation of a
+2.0-D add power in the central zone of the lens
(right) in order to yield a multifocal optic. (Courtesy
of Calhoun Vision Inc.)
Fig. 17.9. A soft and injectable light-adjustable
silicone polymer could be injected into the capsular
bag and then irradiated postoperatively to
achieve emmetropia. Refilling of the capsular bag
would eliminate the creation of potential space behind
the capsular bag and theoretically decrease
the incidence of vitreous detachment. A soft pliable
material could also potentially allow for the
return of accommodation. (Courtesy of Calhoun
Vision Inc.)
the risk of retinal detachment following lens
surgery (Fig. 17.9). By reinflating the capsular
bag with an adjustable polymer, vitreous detachment
and subsequent retinal detachment
risk would theoretically lessen. In addition,
an injectable polymer would allow for the
possibility of utilizing advanced phacoemulsification
techniques through microincisions
of 1.0 mm and implanting an adjustable lens
material through these same minute incisions.