Download Spontaneous Resolution of a Traumatic Cataract Caused by

Spontaneous Resolution of a
Traumatic Cataract Caused by
an Intralenticular Foreign Body
Rofagha S, Day S, Winn BJ, Ou J, Bhisitkul R, Chiu CS
Department of Ophthalmology, University of California San Francisco
The authors state that they have no financial interest in the material
presented.
Introduction
• Intralenticular foreign bodies can be managed
conservatively with removal of the foreign body and
lens preservation1 or more aggressively with primary
cataract extraction and intraocular lens implantation.2
• Several cases have been reported where a traumatic
lens opacity remains localized and visually
insignificant for decades after the initial injury.3,4
• To our knowledge, we report the first case of
spontaneous resolution of a cataract in the modern
literature following capsular violation by an
intralenticular foreign body.
Case
• A healthy 49 year old fireman was cutting wood with a table saw
when he felt a foreign body strike his left eye. He noticed some
mild irritation but no pain or change in vision. He was seen by a
private ophthalmologist in the community who diagnosed a
metal foreign body perforating the sclera posterior to the iris,
penetrating the lens, and referred him to our institution for
further management.
• Upon presentation his uncorrected visual acuity was 20/20 in
the right eye and 20/25 in the left. Pupils were equal, round,
and reactive to light without evidence of an afferent pupillary
defect. Extraocular movements were intact and visual fields
were full to confrontation bilaterally. Intraocular pressures were
12 mm Hg and 13 mm Hg in the right and left eye, respectively.
Case (continued)
• Slit lamp examination was significant for a foreign body
perforating the sclera 2 mm posterior to the inferonasal limbus in
the left eye. The foreign body traveled through the pars plicata
and equatorial lens capsule, and was embedded into the
peripheral lens cortex. Dilated fundus examination was
unremarkable. The patient was taken to the operating room for
repair.
• After exposure, the foreign body external to the sclera was
grasped with serrated forceps and gently pulled from the globe
in its entirety. The metallic foreign body measured 1mm x 0.2
mm x 6mm.
Case (continued)
•
•
•
On post-operative day two, the
patient was noted to have 1+
posterior subcapsular cataract
(PSC) and a small amount of
vitreous hemorrhage adjacent to
the area of injury, without any
evidence of retinal break.
On post-operative day four, in
addition to the PSC, a dense
cortical cataract had evolved
(right) although his visual acuity
remained 20/25.
The cataract had a cruciate
configuration with wave-like
disruption of the stromal
lamellae, and a central apex
presumably indicating the point
of greatest impact.
Case (continued)
•
•
Three weeks after globe repair,
because of the patient’s active
lifestyle, prophylactic retinal
cryotherapy in the area of the
vitreous hemorrhage was
performed.
On post-operative month #1, the
patient subjectively felt his vision
had improved. His vision tested to
20/25 and examination of the lens
revealed resolution of more than
90% of the opacity (right).
Case (continued)
• By the fourth postoperative month, he
continued to report
improved vision,
confirmed by a measured
acuity of 20/20.
• On slit lamp examination,
only a faint imprint of his
original cataract remained
(top right) and a small
outpouching of the
posterior lens capsule was
noted (bottom right).
Discussion
• It has been well documented that intralenticular
foreign bodies may have a self-limited natural
history without progressive cataract formation.1,3,4
• Conservative management with lens preservation
is a valid option, especially to preserve
accommodative potential in young patients, unless
there is intraocular inflammation, lens-related
glaucoma, or sight-threatening siderosis bulbi.
Capsular Response to Injury
• When capsule rupture leads to hydration of the lens cortex, it
has been hypothesized that small, capsular wounds can heal
without progressive cataract formation.4
• According to this theory, once the epithelium proliferates, it
reseals the capsule and restores the ionic balance to the
intralenticular space, stabilizing the lens opacity.5
• Therefore, both the size of the capsular opening and the speed at
which the epithelium lays down new basement membrane will
influence the magnitude of cataract formation.
Can Lens Restore Its
Transparency?
• Less well formulated is how the lens can restore its
transparency. The old ophthalmic literature described well
a rosette cataract from concussive or penetrating injury that
usually remained stationary or progressed, but also
described several cases of complete resolution, first
described by Fuchs in 1888.7
• It has been proposed that resorption of small superficial
lens opacities can occur in a pseudo-lysosomal fashion.
• Alternatively, in young mice, damaged cells within
traumatic cataracts have been seen to undergo apoptosis,
perhaps induced by compression from rapidly proliferating
epithelium.9
Another Theory?
• In our patient, the rapid return of
translucency to the lens cannot be
easily explained by either
mechanism alone.
• Closer analysis of the unique Xconfiguration of the cataract and
the wave-like stromal disruption
leads us to another theory, one of
temporary disturbance to the lens
architecture without formation of
scar.
• We hypothesize that the majority
of the cortical opacity was not due
to direct contact, but due to the
misalignment of lens fibers from
the propagation of a shockwave,
stemming from the missile.
Conclusion
• Within the scope of a month, once the capsule had sealed
and proper ionic balance had returned to the intralenticular
space, we suspect these fibers then realigned and the
original architecture was restored.
• In our patient, it is possible that both the small area of
capsular injury and its equatorial location led to rapid
sealing of the capsular defect, followed by restoration of
the original architecture in misaligned but otherwise
uninjured lens cortex.
• We believe this case represents a new mechanism of lens
injury, one by shockwave, which carries an excellent visual
prognosis and justifies attempts at lens preservation after
trauma.
References
1
2
3
4
5
6
7
8
9
Pieramici DJ, Capone, Jr A, Rubsamen PE, Roseman RL. Lens preservation after
intraocular foreign body injuries. Ophthalmology 1996;103:1563-7.
Moisseiev J, Segev F, Karizman N, Arazi T, Rosenstreich Y, Assia EI. Primary cataract
extraction and intraocular lens implantation in penetrating ocular trauma.
Ophthalmology 2001;108:1099-103.
Cazabon S, Dabbs TR. Intralenticular metallic foreign body. J Cataract Refract Surg
2002; 28:2233-2234.
Dhawahir-Scala FE, Kamal A. Intralenticular foreign body: a D-Day reminder. Clinical
and Experimental Ophthalmology 2005; 33: 659-660.
Keeney AH. Intralenticular foreign bodies. Arch Ophthalmology 1971; 86: 499-501.
Fagerholm PP, Philipson BT. Human traumatic cataract: a quantitative
microradiographic and electron microscopic study. Acta Ophthalmologica 1979; 57: 2032
Duke Elder S: Injuries. In: System of Ophthalmology (Edited by: Duke-Elder S). London
Henry Kimpton 1963, XIV (Part 1): 354-356
Brini A, Porte A, Stoeckel ME. Resorption of necrotic lens material by a newly formed
lens capsule in certain types of cataract. Nature 1963; 200: 796-7.
Hirayama S, Wakasugi A, Morita T, Sakai Y, Mukuno K, Uga S, Shimizu K. Repair and
reconstruction of the mouse lens after perforating lens injury. Jpn J Ophthalmol 2003;
47(4): 338-46.
Acknowledgements
• The authors want to extend special thanks to Mr.
Michael Narahara and Mr. David Clay, ophthalmic
photographers, for their outstanding photographs.
• Resident travel to ASCRS 2008 Annual Meeting was
supported by a educational grant from That Man May
See, Inc., the official support foundation for the
Department of Ophthalmology at the University of
California, San Francisco.