Download Pigment Dispersion after cataract surgery

Severe Iris Pigment
Epithelium Desquamation
After Routine Cataract
Surgery
Kendall R.B. Dobbins, MD
Geisinger Medical Center
Author has no
financial interest
Purpose:
• To present a unique case of severe iris
pigment epithelial desquamation following
routine cataract surgery and to investigate
whether the case could be an unusual
variant of toxic anterior segment syndrome
(TASS).
Methods:
• A 66 year-old woman with no pre-operative history of
pigment dispersion syndrome underwent routine
clear-corneal cataract surgery OS. Below is an
image of the iris OD to provide a sense of the pre-op
status of the iris OS.
Methods
• At the one-day post-operative visit, there were 4+ diffuse iris
trans-illumination defects, 4+ iris pigment cells suspended in the
anterior chamber, a significant amount of pigment cells coating
the corneal endothelium and iris stroma, and pigment dispersionrelated ocular hypertension with an IOP of 31 OS (see images).
Methods
• The intraocular lens remained well-positioned within the
capsular bag (see images), ruling out a mechanical cause
for the severe pigment dispersion. An investigation was
undertaken to try to determine the etiology of the event and
to clarify whether or not the case could be a variant of Toxic
Anterior Segment Syndrome (TASS).
Results
• There was nothing unusual about the
substances used in the eye or on the surface
of the eye
– Substances in the eye:
• 500cc BSS with 0.5cc Epi 1:1000 (Alcon)
• Amvisc Plus (B+L)
– Substances on the surface the eye:
• BSS 15cc (Alcon)
• Povidone Iodine 5%--diluted from 10% solution by
hospital pharmacy under sterile conditions (Aplicare)
• Prednisolone acetate, Gatifloxacin, and Timolol GFS
drops immediately post-operatively
Results
• However, further investigation of the cleaning
and sterilization processes at our ASC
revealed that enzymatic detergent had been
used when cleaning instruments in the
ultrasonic cleaner and tap water had been
used to flush the hand-pieces, both of which
were considered potential sources of
endotoxin.
Results
• Literature Search
– Brouzas et al. Severe toxic effect of methylene
blue 1% on iris epithelium and corneal
endothelium. Cornea 2006 May;25(4):470-1.
– Monson, Mamalis, Olson. Toxic anterior segment
inflammation following cataract surgery. JCRS
1992 Mar;18(2)184-9. 3 cases with widespread
corneal edema, fixed pupil, and significant iris
atrophy.
– No reports of isolated acute pigment dispersion
S/P routine Phaco with IOL (without corneal
edema).
Results
• Discussions with the head of the U.S. TASS
task force deemed that this case was unlikely
to be TASS since the corneal endothelium
remained essentially intact while the iris
pigment epithelium was so severely affected.
In the two years following this case, there
have been no further repeat cases in our
department.
Conclusion
• There are no reports of isolated acute diffuse
non-mechanical pigment dispersion without
associated corneal edema after routine
cataract surgery, making this case very
unique. While the etiology of this event
remains unknown, this case demonstrates
how a thorough evaluation of the sterilization
process of cataract surgical instruments
should be performed at all surgery centers.
Conclusion
• Changes in sterilization in our ASC:
– Instruments placed in ultrasonic cleaner
without enzymatic detergent (thought to be
a possible source of endotoxin).
– Handpieces are flushed with sterile
distilled water instead of tap water.
– Instruments put through washer/disinfector
machine daily.