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Congenital Duplication of the Anterior Segment With Central Hamartomatous Plaque
Arch Ophthalmol. 2002;120:1377-1379.
A child born of a full-term pregnancy had unilateral splitting of the
anterior segment of the right eye associated with choristoma. No other craniofacial
abnormalities were found. The globe was slightly increased in size but was
normal in shape. The 2 corneas were separated by a choristoma. Pathological
examination revealed splitting of the anterior segment with 2 corneas, 2 lenses,
and 2 irides. Only 1 posterior segment was observed, including a hematic vitreous
associated with a dysmorphic retina. As diplophthalmos, this congenital malformation
may be induced by primary optic vesicle development disturbance.
Clinical History
A mature female infant was born at week 41 of gestation in December
1998 with a right eye malformation. The healthy mother, aged 34 years, had
experienced only a fever during the first month of the pregnancy. Her 3 previous
pregnancies were normal. There was no history of exposure to x-rays or drugs.
Routine serologic test results were all negative. An ophthalmologic examination
was performed 1 week later. A large, yellow-pink choristoma was localized
in the middle of the eye, dividing the globe into a medial eye and a lateral
eye (Figure 1). The lid apertures
and eye mobility were normal. The cornea of the medial eye was hazy, but there
was a noncolobomatous round iris. The cornea of the lateral eye was more transparent,
and a noncolobomatous round iris with lens ectopia and cataract was detected.
The fundus was not visible. Ultrasonography revealed 2 different lenses, with
densification of the anterior vitreous, as seen by direct ophthalmoscopy.
Only 1 optic nerve was present. After examination with the patient under general
anesthesia, the choristoma was resected. Karyotype analysis was performed,
and no anomalies were detected.
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Figure 1. Clinical appearance of the right
eye. Two distinct corneas are separated by a dermoid.
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By age 6 months, the globe and the lids had increased in size. However,
the child experienced ocular exposure. Both orbits were normal in size and
shape as determined by computed tomography. Right-sided proptosis was noted,
with increased globe size (right, 21 x 22 mm; left, 19.5 x 19.8
mm). A lateral tarsorrhaphy was therefore performed with the patient under
general anesthesia.
When the child was 18 months old, she again experienced ocular exposure
despite the previous lateral tarsorrhaphy. The palpebral apertures were large.
Electrophysiologic features revealed no evoked potential in the right eye
(data not shown). Enucleation was performed using a hydroxyapatite-polyglactin
910 [vicryl]–wrapped ball (FCI, Issy les-Moulineaux, France) of 18 mm;
6 months later, a lateral canthoplasty was performed to adjust the position
of the lids.
Pathological Examination
On gross examination, the first lesion corresponding to the choristoma
was flattened and discoid, measuring 7 x 5 x 1 mm. Under light
microscopy, the surface was lined by a squamous, poorly keratinized epithelium,
devoid of keratohyalin granules. No Bowman membrane could be found between
this epithelium and the underlying connective tissue, which contained many
capillaries and did not exhibit corneal lamellar organization. The whole lesion
was referred to as a dermoid.
On macroscopic examination, the formalin-fixed eye measured 19 mm in
diameter (Figure 2). The insertion
sites of the 6 external eye muscles were normal. The 2 corneas each measured
7 mm across, and there remained a thin white band between them, corresponding
to the base of the previously removed dermoid. Examination of a horizontal
section disclosed anterior splitting of the anterior segment. There were 2
distinct 3-mm-diameter lenses. The vitreous was retracted, and the retina
was almost completely detached. The space between the detached retina and
the sclera was filled with a serous, xanthochromic liquid. The retina was
still attached to the optic nerve head. Histologic examination disclosed the
well-differentiated corneal epithelium, the Bowman membrane, the corneal stroma,
and the posterior endothelium on both corneas. The Descemet membrane was normal
in the lateral cornea but was irregularly thickened in the medial cornea.
The remnant tissue between the corneas was similar to limbus, without the
Bowman membrane. The 2 irides were atrophic, and there were histologic hallmarks
consistent with a moderate white cataract. In both lenses, the posterior capsule
was adherent to disorganized retinal tissue, which has been clinically called
densification of the anterior vitreous (Figure
3). In this tissue, only 3 components of the normal retina could
be recognized: the outer limiting membrane, the photoreceptor layer, and the
outer nuclear layer. They were arranged in ribbons or tubes. "Rosettelike"
tubes were empty and likely lined by outer granular layer cells. Other "pseudo-rosettelike"
tubes had no lumen, the photoreceptor cells arranging around capillaries (Figure 4). There was 1 vitreous, and behind
it was a dysmorphic retinalike tissue, situated in the first segment of the
optic nerve, outside the uveal tract, and internal to the lamina cribrosa.
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Figure 2. Axial section of the right eye.
MAI indicates medial atrophic iris; LAI, lateral atrophic iris; LL, lateral
lens; ML, medial lens; DR, dysplastic retinal tissue; CB, ciliary body; HV,
hematic vitreous; ON, optic nerve; and R, retina (hematoxylin-eosin, original
magnification x2.5).
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Figure 3. Close-up view of the anterior
segment. LAI indicates lateral atrophic iris; LL, lateral lens; ML, medial
lens; DR, dysplastic retinal tissue; and DB, dermoid base (hematoxylin-eosin,
original magnification x25).
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Figure 4. Close-up view of the dysplastic
retinal tissue. Cells are arranged in ribbons or tubes (hematoxylin-eosin,
original magnification x100).
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Comment
The eye is a complex structure that originates from primordial tissues
derived from a variety of sources, including the wall of the diencephalon,
the overlying surface ectoderm, and immigrating neural crest cells. Normal
development of the eye depends inter alia on an ordered sequence of induction,
so that growth, migration, and differentiation begin in the right place and
at the right time and proceed in the right direction. Eye development occurs
during the second week of gestation as 2 anterolateral, convex depressions
of the neural plate, the optic grooves.1 They
enlarge rapidly during the third or fourth week to form the primary optic
vesicles. Throughout its development, the surface ectoderm and several layers
of mesoderm form the future lens, cornea, stroma of the iris, and ciliary
body structures of the anterior chamber filtration apparatus. Any disturbance
in growth during this early period causes serious ocular anomalies. Defects
arising later, after further differentiation of the eye has already been accomplished,
usually cause less severe but more localized damage. Anophthalmia and congenital
cystic eye, cyclopia, synophthalmia, or diplophthalmos are classified in major
defects. Unilateral diplophthalmos is defined by 1 normal and 2 separate eyes
from 2 anlagen in 2 orbits with 2 optic nerves, which differs from our case.2-3
We report herein the first case of congenital duplication of the anterior
segment associated with a dermoid. Dermoids are tumorous growths on the exterior
of the eye derived from tissue not usually present. They occur in 1 to 3 of
10 000 live births. Associated ocular abnormalities include scleral and
corneal staphyloma, aniridia, congenital aphakia, cataract, and microphthalmia.4-6 Experimental
studies have described septation of the anterior segment. In 1937, Perri7 removed an optic vesicle with its ectodermal coverage
in Rana esculenta and Bufo vulgaris, turned it 180°, and reimplanted it. Almost regular double eyes
were formed with doubling of lenses, but with just one posterior segment,
as a septation of the optic vesicle, which differs from diplophthalmos.7 Experimental studies8-9 suggest
that this congenital malformation may be induced by primary optic vesicle
development disturbance. Hyperthermia during the first trimester of pregnancy
can disrupt normal organogenesis or growth of the primary optic vesicle, and
we surmise that this may have been the cause of the malformation noted in
our case.8-9
AUTHOR INFORMATION
We thank S. Defoort-Dhellemmes, MD, for providing the electrophysiologic
feature and S. Manouvrier, MD, PhD, for pediatric examination.
Frédéric Mouriaux, MD;
Marie-Paule Leroy-Rattier, MD;
Claude-Alain Maurage, MD;
Françoise Guilbert, MD;
Jean François Rouland, MD
Lille, France
Ian Cree, PhD, FRCPath
Portsmouth, England
Corresponding author: Frédéric Mouriaux, MD, Service
d'ophtalmologie, Hôpital Schaffner, Route de la Bassée, 62307
Lens, France.
Reprints: Jean François Rouland, MD, Service d'ophtalmologie,
Hôpital Huriez, 59037 Lille CEDEX, France.
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