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CATARACT INCISION LONG TERM FOLLOW-UP WITH IN
VIVO CONFOCAL MICROSCOPY
Martone G, Traversi C, Casprini F, Ciompi L,
Caporossi A
Department of Ophthalmology and Neurosurgery,
University of Siena, Italy
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INTRODUCTION The aim of the cataract surgery is
to obtain the desidered effect with minimum
trauma to the eye. Major advances in the
techniques used for cataract surgery during the
last decades have made it possible to decrease
the size of the incision through which the
surgery is performed (1). This decrease in the
incision size has proved to be associated with a
significant decrease in postoperative intraocular
inflammation, less wound-related complications,
less surgically induced astigmatism, less
surgical time, and shorter postoperative
rehabilitation (2). Recently, several
researchers studied in vitro and in vivo the
anatomy of cataract incision under different
conditions using optical coherence tomography
(3,4). In vivo confocal microscopy (CM) is
becoming a useful diagnostic tool for ocular
surface imaging to diagnose and describe corneal
diseases. It can provide details of ocular
structures at the cellular level (5). The aim of
the study is to describe the morphology by CM of
corneal tissue surrounding the incision after
phacoemulsification.
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MATERIALS AND METHODS A prospective study was
conducted of 30 eyes of 20 patients who had
uneventful phacoemulsification in the Department
of Ophthalmology and NeuroSurgery of the
University of Siena. All patients underwent a
standardized small incision phacoemulsification
with foldable IOL implantation by injector in the
capsular bag. A 2.75-mm wide, self-sealing
superior corneal tunnel was created. If sealing
was inadequate, a 10-0 nylon suture was placed.
CM (HRT II, Heidelberg Engineering, Germany) was
performed within 1 week (Early), after 3 months
(Medium) and after 1 year (Late) of cataract
surgery. The microscopic confocal images (400 µm
x 400 µm) were acquired from the corneal incision
in the superior periphery of the cornea. During
the examination, all subjects were asked to
fixate inferior light target in order to good
visualization of the incision. The external
entry, the tunnel in the corneal stroma and the
internal entry were examined.
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RESULTS
EARLY CONFOCAL FEATURES
CM analysis revealed epithelial alterations at
the external entry with edema (hyporeflective
areas between epithelial cells) and distorsion of
the epithelial cells. Inflammatory signs with
mononuclear and dendritic cells were also
observed. Subepithelial nerve plexi were not
clearly identified and the nerve fibers appeared
tortous and hyperreflective. In the corneal
stroma, alterations to the tissue lining the
tunnel were found. Sometimes the normal
arrangement of the collagen fibers was grossly
disorganized with dark striae and reflective
microdots. In the area adjacent to the incision
many activated keratocytes and microlacunae of
edema tissue were also found. On the internal
entry, the endothelium revealed thermic damage
with loss of some endothelial cells.
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EARLY CONFOCAL FEATURES

• Epithelial edema
• Inflammatory cells at the epithelial layer
• Tortuous and hyperreflective nerve fibers
• Stromal edema
• Hyperreflective bodies at the tunnel
• Descemet tear
• Minimal endothelial cell loss

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RESULTS
MEDIUM CONFOCAL FEATURES
Morphologic changes of the tunnel at 3 months
follow-up revealed some superficial epithelial
alterations and moderate stromal edema near the
tunnel. Activated keratocytes was present, while
inflammatory cells werent seen in the area of
the incision. The endothelial cells near the
internal entry of the incisions showed a good
renewal and normal morphology.
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MEDIUM CONFOCAL FEATURES

• Reduction of epithelial and stromal edema
• Epithelial disarrangement
• Inflammatory cells at the epithelial layer
• Reduction of hyperreflective nerve fibers
• Activated keratocytes
• Endothelial organization

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RESULTS
LATE CONFOCAL FEATURES
Late morphologic changes of the tunnel presented
highly reflective scar tissue with localized
neovascularization. Dark striae with different
orientations and dimensions and inclusion
microdots were also evident. No inflammatory
cells were seen in the area of the incision. The
internal entry of the incisions showed a low
distortion of the endothelial cells. In case of
suture, an important fibrocellular reaction
around nylon tissue can be present.
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LATE CONFOCAL FEATURES
Multiple-dark striae in contrast with the
moderate reflectivity of the stroma.
Normal morphology of the corneal epithelium.

• Low epithelial disarrangement
• Localizated neovascularization
• Fibrous at the epithelial layer
• Dark stromal striae
• Important reflective scar
• Few activated keratocytes
• Low endothelial riarrangement

Highly reflective scar extending from the basal
membrane to the immediately underlying stroma.
Regular aspect of endothelial cells at the level
of the incision.
Corneal suture 1 year after surgery. Around nylon
material, a fibrocellular tissue reaction were
observed.
Some hyperreflective inclusions (arrow) in the
bed of the tunnel.
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DISCUSSION Wound trauma has been demonstrated
with scanning electron microscopy following
coaxial phacoemulsification (6). Corneal wound
architecture was altered in all eyes (7). To our
knowledge, this is the first time that important
details of the cataract incision are studied by
CM. It allows the detection of microstructural
changes of the corneal morphology at the level of
the tunnel. We observed that these alterations
changed with time. In conclusion, CM can be
useful to study the wound healing of cataract
incision because it yielded superior diagnostic
details in comparison to the limited
magnification and resolution of conventional
slit-lamp biomicroscopy. Larger studies should be
carried out to study in vivo further the changes
induced at the level of the cornea induced by the
surgery.
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