Exfoliation Syndrome and Exfoliative Glaucoma 213in the phacoemulsification alone group, the combined phacoemulsification and
trabecular aspiration group, and the combined phacoemulsification and
trabeculectomy group were 36%, 64% and 78%, respectively. The proportions
of medication-free well-controlled patients 2 years after the above procedures
were 9%, 38% and 65%, respectively.
Cataract surgery is frequently necessary in XFG due to nuclear cataract
induced by increased oxidative stress in the anterior chamber [28,30,33].In
addition, cataract surgery offers a clinically significant IOP decrease in XFG
and XFS eyes with elevated IOP [93-96]. It has been suggested that the IOP-
lowering effect of cataract extraction in eyes with XFG and XFS is due to a
combination of the following mechanisms: widening of the anterior chamber
angle, removal of a large portion of the exfoliation-producing anterior capsule,
decrease of irido-lenticular friction (which limits the release of pigment and
exfoliation material postoperatively), aspiration of deposited debris from the
trabecular meshwork during surgery, and enhancement of the trabecular
outflow as a consequence of low-grade inflammation (the hypothesized
mechanism being similar to that seen after argon laser trabeculoplasty
[14, 93 ]). In a 2-year, multicenter, prospective cohort study the IOP-lowering
effect of phacoemulsification was assessed in 71 cataract patients with
exfoliation (29 patients had XFG) and 112 without exfoliation [93]. Eyes with
XFS and XFG had a significantly larger IOP reduction than POAG patients
and non-glaucomatous controls. Remarkably, the investigators found that the
ocular hypotensive effect of cataract surgery in the exfoliation group was
associated with the volume of the irrigating fluid. This suggests that the IOP-
lowering effect of cataract surgery can be attributed to the intraoperative
removal of debris. The results of this prospective study fit well to earlier data
from retrospective case series [94,95]. In another retrospective study
conducted on 1122 XFS and XFG eyes followed for 7 years, the postoperative
IOP reduction was proportional to the preoperative IOP [96]. A recent
retrospective study found that the proportion of XFS patients who converted to
XFG after phacoemulsification within the more than 6-year long follow-up
period was lower than expected, and the mean IOP of eyes with exfoliation at
the end of the follow-up period was 2.6 mmHg lower that the mean
preoperative value [97].
However, cataract surgery in XFS and XFG is associated with several
disease-specific surgical challenges [14,19,98]. These include Zinn’s zonule
laxity and/or fragility, phacodonesis, lens subluxation or luxation, inadequate
mydriasis, hard nucleus, fragile capsule and increased risk of vitreous loss. In
the postoperative period common complications include corneal edema due to