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Clinical
Conjunctiva and Subconjunctival Tissue
Venkatesh Prajna, Muralidhar Rajamani, Aravind Eye Hospital, Madurai
Anatomy
The conjunctiva is a thin, translucent, vascular
mucous membrane that lines the inner surface of
the eyelids and the anterior surface of the eyeball
as far as the limbus. This tissue is arranged in a saclike fashion and is composed of a palpebral region
(covering the inner aspects of the lids), a bulbar
region (covering the surface of the sclera), a
forniceal region, and a medial semilunar fold.
While the palpebral conjunctiva shares
its blood supply with the eyelids, the bulbar
component is supplied by the anterior ciliary
arteries. The nerve supply to the conjunctiva is
through the lacrimal, supraorbital, supratrochlear,
and infraorbital branches of the ophthalmic
division of the trigeminal nerve.
The conjunctival epithelium varies from 2
to 5 cells in thickness and is continuous with the
corneal epithelium at the limbus and with the
skin at the margin of the lids. While the bulbar
conjunctiva is lined by a stratified non-keratinized
squamous epithelium, the forniceal and tarsal
regions are lined by columnar and cuboidal types,
respectively. A key constituent of the cellular
architecture is the presence of goblet cells, which
accounts for 10% of the basal cells of the conjunctival epithelium. These cells are more prevalent in
the medial forniceal and palpebral regions, and
play a vital part in secreting the mucin component
of the tear film. There is an increase in the number
of these cells during chronic inflammation of
conjunctiva, while conditions like pemphigoid
and vitamin A deficiency causes a decrease.
Other cell types which nestle within the epithelial
layers include melanocytes, Langerhans' cells, and
intraepithelial lymphocytes.
Beneath the epithelium lies a loose structure
called the substantia propria. This structure
contains different cell types which mediate
immune responses (mast cells, plasma cells,
eosinophils, and lymphocytes) interspersed in a
vascular network. This arrangement of immune
cells, commonly referred to as conjunctivaassociated lymphoid tissue, existing in a vascular
environment, is continuously exposed to potential external infective agents and allergens thus
serving as a perfect setting for inflammation to
set in.
Beneath the conjunctiva lies a fibroelastic
tissue, Tenon's capsule, which surrounds the eye
ball from the corneoscleral junction to the optic
nerve. Tenon's capsule is thicker in children and
contains more fibroblasts. Hence surgeries like
trabeculectomy performed in children, especially
without adjuvant procedures like intraoperative
use of antimetabolites, may fail due to the
aggressive healing response induced by these
fibroblasts.1
Conjunctiva in systemic disease
A careful flashlight examination of the conjunctiva
in a brightly lit environment often provides
comprehensive information about a potential
underlying systemic disorder. Information about
color, lustre, abnormalities in vascularization, and
pigmentation help to suspect an underlying ocular
or a systemic cause. A slit-lamp evaluation can
then be carried out to focus on the specific area
of the pathology.
Vitamin A deficiency
This systemic condition affects organs throughout
the body. The ocular manifestation is termed
xerophthalmia and affected individuals present
with night blindness, conjunctival xerosis, Bitot's
spots, corneal xerosis, keratomalacia, and the
"xerophthalmic" fundus.
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In this condition, the conjunctival epithelium
is transformed from the normal columnar to the
stratified squamous type. There is an associated
loss of goblet cells, formation of a granular cell
layer, and keratinization of the surface. The
conjunctiva loses its normal lustre and is altered
into a dry or unwettable one (Fig. 1.1). It is almost
always bilateral. A classic ocular sign is Bitot's
spots, which is a superficial, scaly, gray area on
the interpalpebral region of the bulbar conjunctiva (Fig.1.2). Corynebacterium xerosis can
colonize these spots, and produce a foamy
appearance because of the gas-forming nature
of these organisms. If untreated, the condition
involves the cornea, causing corneal xerosis and
finally corneal melting, or keratomalacia.
The diagnosis of xerophthalmia is often
clinical and does not require any additional
Fig. 1 Xerophthalmia. Dry, lustureless, inferior bulbar
conjunctiva showing a wrinkled appearance.
Fig.2 Bitot's spot. A superficial, scaly, foamy Bitot's
spot of the bulbar conjunctiva
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investigations. In doubtful cases, impression
cytology of the superficial layers of the conjunctival
epithelium may be helpful to show the loss of
goblet cells and keratinization of epithelial cells.
Oral administration of vitamin A is preferred
because it is safe, cost-effective, and highly
effective. In affected children above 12 months of
age, retinol palmitate (110 mg) or retinol acetate
(200 000 IU) are given orally immediately and the
dose is repeated the following day. An additional
dose should be given 2 weeks later to boost liver
resources. Children between 6 and 11 months
should receive only half the above-mentioned
dose, and children less than 6 months one-quarter
of the dose.
Parenteral administration is indicated in
those children with conditions such as persistent
vomiting, severe stomatitis, and attendant
difficulty in deglutition, severe diarrhea with
malabsorption, and septic shock. Such children
can be treated with intramuscular injection of 55
mg of water-miscible retinol palmitate (100 000
IU), which replaces the first oral dose. This is
repeated the next day. Children of less than 1 year
are treated with vitamin A in half the prescribed
dosage. After the acute phase is over, dietary
supplements with provitamin A-rich foods, should
be provided.
Xeroderma pigmentosa
This condition is inherited as an autosomal
recessive disorder. Symptoms appear in early
childhood. Affected individuals present with
extreme photophobia, photosensitivity, and typical
dark pigmentary changes in the skin. They are
at an increased risk for malignant lesions in sunexposed mucocutaneous and ocular structures
(Fig. 3A). There is an impaired ability to repair
ultraviolet light-induced DNA damage, which
results in accumulation of the damaged DNA.
This accumulation of abnormal DNA leads to
chromosomal mutation and cell death and is
thought to be responsible for neoplasms in these
individuals.
Vol. XVI, No.2, April - June 2016
A
9
B
Fig. 3 Xeroderma pigmentosa. (A) The widespread skin
pigmentation can be seen in this girl of Indian origin
Fig.3 (B) The conjunctiva was affected by
multifocal recurrent squamous cell carcinomas.
Conjunctival involvement occurs mostly in
the interpalpebral area in the form of xerosis,
telangiectasia, chronic conjunctival congestion,
pigmentation, pinguecula, and pterygium.
Ocular surface neoplasms such as squamous cell
carcinoma, basal cell carcinoma, and malignant
melanoma may occur, with a predilection
for the limbal area (Fig.3B). Corneal changes
include exposure keratitis, band-shaped nodular
keratopathy, scarring, ulceration, vascularization,
and perforation. The posterior segment is usually
spared. Elevated symptomatic conjunctival
nodules and suspected neoplasms may require
repeated excisions; otherwise the treatment is
symptomatic.
either autosomal dominant or X-linked in
their inheritance pattern. A rare autosomal
recessive form, lamellar icthyosis, occurs. In all
these conditions, dry scaly lesions are present
predominantly over the upper half of the body,
mainly around the neck, mouth, and trunk. The
conjunctiva may become inflamed primarily or
secondarily due to lid anomalies like ectropion."
A papillary reaction may develop (Fig.4). The
treatment is to provide adequate lubrication and
to correct the lid abnormali ties, if present.
Sturge-Weber syndrome
This is a congenital disorder with a classical triad
of cutaneous facial angioma, leptomeningeal
angioma, and ocular involvement. The facial
angioma typically occurs in the distribution
of the ophthalmic division of the trigeminal
nerve. Dilated episcleral and conjunctival vessels
with aneurysm formation in the limbal area
are commonly seen. Glaucoma is a frequent
accompaniment, especially in patients with severe
onjunctival involvement.
Icthyosis
Ichthyosis is a heterogeneous family of at least
28 genetic skin disorders. Most pedigrees are
Anemia
Conjunctival pallor is a sensitive and commonly
used sign to detect anemia in children. This
examination should preferably be done in broad
Fig.4 Icthyosis. (A) There is keratinization of the
upper palpebral conjunctiva secondary to ectropion
of the upper lids. (B) The classical 'stretched out" skin
lesions are seen predominantly around the mouth
and neck.
10
daylight and correlated with the other systemic
indicators. An important causative factor,
especially in underdeveloped economies, is
systemic helminthiasis. Conjunctival pallor can
be masked by conjunctival inflammation, notably
trachoma.
Leukemias
Involvement of the conjunctiva is not a common
feature of leukemia. It occurs in approximately 4%
of all patients with this disease. However, it may
be the initial sign of the disease or of a relapse.
Herein lies the importance of early recognition.
The affected individuals present initially with
congestion of the bulbar (particularly the
perilimbal area) or the palpebral conjunctiva.
In some instances, the conjunctiva may be
erythematous and chemotic. The lesions are
firm and non-tender and often associated with
subconjunctival hemorrhage.
Histopathologically, the cells infiltrate all
layers of the substantia propria. The infiltration
may be diffuse or patchy and typically localize
around the blood vessels. The conjunctival lesions
usually respond rapidly to systemic chemotherapy.
Measles keratoconjunctivitis
Me a s l e s t y p i c a l l y p ro d u c e s a b i l a t e r a l
keratoconjunctivitis. The characteristic Koplik's
spots may be seen in the conjunctiva. The plica
semilunaris may be swollen. Epithelial keratitis
may supervene early in children and late in
adults. The signs usually resolve without sequelae
in the immunocompetent and well-nourished.
Treatment is symptomatic and topical antiinflammatory therapy may provide relief. In
children with protein/energy malnutrition, this
disease can be particularly devastating. Vitamin
A deficiency is also present and may present with
rapid keratomalacia. Secondary bacterial infection
is common in immunodeficient individuals.
Alkaptonuria
This is a rare autosomal recessive disorder in
which an affected individual's urine turns a dark
brown-blackish color when exposed to air. It is
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linked to chromosome 3q21-q24, caused by a
deficiency of homogentisic 1,2-dioxygenase5. This
deficiency results in accumulation of homogentisic
acid, which gets deposited in various tissues and
organs. Systemic features include pigmentation
over the face and nails, calcific and atherosclerotic
heart disease, and arthritis. Ocular manifestations
include a brown to black pigmentation of the nasal
and temporal sclera especially in the area of the
horizontal rectus muscle insertions. Pigmentation
of the cornea has been reported.
Ataxia telangiectasia (Louis-Bar
syndrome)
The condition is a rare autosomal recessive
disorder characterized by early onset cerebellar
ataxia, oculocutaneous telangiectasia, ocular motor
apraxia (saccadic initiation failure), dysarthria and
immuno deficiency. Of these, ataxia is the first
sign and is progressive. Chromosomal fragility and
increasing susceptibility to ionizing radiation result
in a predilection to malignant disorders such as
lymphomas and leukemias. Affected individuals
tend to have high levels of alpha-fetoprotein in
their blood.
The most characteristic ocular involvement
is the appearance of a conjunctival telangiectasia
that appears around the first decade of life. This
lesion is usually seen in the interpalpebral bulbar
conjunctiva, but may extend to the fornices. It is
caused by ultraviolet damage and can be prevented
or minimized by early and consistent use of
100% UV filter lenses. Other associated disorders
include hypometric saccades, horizontal ocular
motor apraxia, deficient accommodative ability,
strabismus, and nystagmus.
Fabry's disease
This X-linked disease is a disorder of lysosomal
storage caused by a deficiency of alpha-galactosidase
A which degrades glycosphingolipid components
of the plasma membranes. This deficiency results
in accumulation of glycosphingolipids, especially
globotriaosylcerarnide." Conjunctival vascular
tortuosity, telangiectasia and cornea verticellata
are common manifestations.
Vol. XVI, No.2, April - June 2016
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Osler-Weber-Rendu Syndrome
This is a rare autosomal dominant disorder of
blood vessels that can cause excessive bleeding. It is
characterized by vascular dilatations in a variety of
organ systems. Systemic features include epistaxis,
dyspnea on exertion, gastrointestinal bleeding,
hemoptysis, and hematuria. The classical ocular
abnormality detected is conjunctival telangiectasia.
It may present with bloody tears or frank
external hemorrhage. Retinal tel- angiectasia and
arteriovenous malformations have been reported.
These vessels are stable and can be distinguished
from neovascular bundles by the absence of leakage
on fundus fluorescein angiography.
Sickle cell disease
The conjunctival signs in this condition are fairly
specific.Comma-shaped capillary and venular
microaneurysms, which disappear under the
heat of the examining lamp, are noted in the
inferotemporal quadrant of an otherwise pale
conjunctiva. These aneurysms reappear after
application of a mild vasoconstrictor. These
vascular anomalies are exaggerated during sickling crises.
Conjunctival tumors
Hamartomas
Hamartomas are congenital overgrowths of
a normal tissue at their naturally occurring
site. Hemangiomas are the most common
hamartomatous lesion. They are of two types:
capillary and cavernous. The capillary type is more
common and can be either an isolated conjunctival
lesion or part of a lesion involving the orbit and
lids as well. These lesions are detected shortly after
birth as elevated, soft nodules (Fig. 5) and usually
grow and become prominent in the first year of
life after which a process of involution occurs. No
active intervention is necessary in the vast majority
of these cases.
Rarely, the lids, periorbital tissue, conjunctiva,
and deeper orbital tissues may also be involved.
Extensive angiomatous lesions may preclude
Fig.5 Subconjunctival capillary hemangioma in an
otherwise normal child. Although it had regressed
spontaneously from being quite large at birth, it was
prone to repeated subconjunctival hemorrhages. On
this occasion the hemorrhage is contained within
the subconjunctival tissue but can be seen to be
spreading anteriorly.
visualization of the cornea. Lid involvement
causes ptosis. A deeper orbital involvement may
cause proptosis which increases with the Valsalva
maneuver. Astigmatism can be present if the
tumors press on the globe.
Amblyopia may develop because of
anisometropia or, rarely, stimulus deprivation.
Optic nerve compression, strabismus, and exposure
keratitis may be associated with some cases.
lntralesional or systemic steroids or propranolol
are used when necessary (almost always) for an
orbital component; the response rate is 30-60%.
Systemic interferon alpha-2a, previously reserved
for life-threatening hemangiomas." is no longer
used due to its side effects.
Cavernous hemangioma is a much rarer and
larger lesion than the capillary type. lt has a higher
propensity to involve deeper structures. This
tumor does not regress spontaneously and the
management is by surgical excision.
Choristomas
Choristornas are congenital tumors comprising
a proliferation of normal cells in an abnormal
location. Dermoids and lipoderrnoids are the
most common choristomas that present in the
conjunctiva. Dermoids are firm lesions with a
12
Fig.6 Dermoid. A temporallimbal dermoid in a
5-year-old boy causing significant astigmatism. Hair
growth is seen on the surface.
predilection for the limbus. The surface can either
be smooth, dome, shaped or keratinized with
hair formation (Fig. 6). A dermoid contains all the
tissues of the skin including the dermal adnexal
structues such as sebaceous glands and hair. They
can present either as an isolated lesion or as a part
of goldenhar's syndrome (oculoauriculovertebral
dysplasia), in which the structures that are derived
from the first branchial arch are also affected.
Dermoids have a tendency to grow during
puberty. They are usually asymptomatic, but
large dermoids can cause irritation, cosmetic
disfigurement, or significant astigmatism. In these
situations, surgical excision can be considered. As
these tumour have a tendency to invade deeper
structures, donor corneal scleral tissue should be
available at the time of surgery10.
Lipoderrnoids are softer, yellow-colored lesions
often occur ring at the lateral canthal region. In
most instances, the posterior extension cannot be
demarcated clearly. Dermal adnexa structures are
not seen histopathologically. They selden require
any treatment. Surgery, if required, should be
performed with extreme caution to avoid damage
to other structures, especially the lacrimal gland,
and because extensive excision predisposes to
symblepharon.
Epithelial tumors
Squamous papillomas present as fleshy and often
multiple pedunculated tumors in children. They
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have a vascular stalk surrounded by acanthotic
epithelium and are seen in the caruncle, fornix,
and eyelid margin. They are caused by the
human papilloma virus type 6. Viral shedding
can cause large, confluent areas of ocular surface
involvement. The surface of a papilloma flows out
like branches of a tree with small vascular fronds on
the surface. Topical mitomycin (0.02%) is useful
in reducing the size of the tumor. It is applied twice
a day for 15 days. Depending on the response, a
second or third cycle can be repeated, with a drugfree interval of 15 days. Topical interferon therapy
also seems to have some benefit. If the lesion
does not respond to these medications, excision
followed by cryotherapy can be performed.
Keratoacanthomas are tumors characterized by
pseudoepitheliomatous hyperplasia with a central
keratin plug. This tumor presents as a painless,
firm, grayish-white keratotic nodule which grows
rapidly over a period of 3-4 weeks. This benign
tumor is often confused with squamous cell carcinoma. Treatment is by complete surgical excision
with application of cryotherapy to the base.
Lymphangiectasia
This condition is characterized by dilated
lymphatic channels and may be diffuse or
localized. The lesion usually occurs in the
interpalpebral space and may accumulate blood
episodically because of communication with a
vein. This can cause surrounding conjunctival
edema and a subconjunctival hemorrhage. Small
lesions can be observed, but larger lesions require
excision.
Lymphangiomas
These tumors are rare and are hamartomatous
proliferations lined by endothelium. There is
no known hereditary or systemic association.
Clinically, in the conjunctiva, they present as clear
vessels with variably sized clear fluid-filled cysts
either alone or interspersed amongst blood-filled
hemangioma vessels. They may increase in size on
Valsalva maneuver. Hemorrhage into an orbital
lymphangioma can produce rapidly increasing
proptosis and present as an ophthalmic emergency
Vol. XVI, No.2, April - June 2016
the presence of subconjunctival and buccal
lymphangioma tissue may be a useful clinical sign
of the underlying cause.
Rhabdomyosarcoma
This is the most common malignant orbital
tumor in children. Conjunctiva is the source of
the primary tumor in around 12% of patients
with orbital rhabdomyosarcoma.11 The superior
and superonasal areas are commonly involved.
They present as light brown colored elevated
lesions and may be confused for focal areas of
inflammation, papillomas, capillary hemangiomas,
or conjunctival cysts. Lack of response to
medical management and rapid progression is
a characteristic feature which should alert the
clinician. Histopathologically, it comprises loosely
coherent spindle cells in a myxoid stroma. MRI is
needed to reveal orbital extension. Treatment is by
radiotherapy and adjuvant chemotherapy.
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Pigmented lesions of the conjunctiva
Pigmentation of the conjunctiva is a common
occurrence. The lesions are mostly benign
in nature, but rarely can assume a malignant
potential. A documented progression of these
lesions is a clear indication for surgical removal.
Conjunctival nevus
This is one of the commonest pigmented lesions
of the eye. Small, circumscribed lesions have little
malignant potential and need not be surgically
excised (Fig.7A). However, nevi that show
progression, or show features suggestive of feeder
vessel vascularization, should be excised (Fig.
7B). Nevi can be either junctional, compound,
or subepithelial in type. Injunctional nevi,
the melanocytes are restricted to the basilar
Neurofibromas and neurilemmomas
These tumors arise from the Schwarm cells which
lie within the nerve. While neurilemmomas are
discrete masses, neurofibromas may present as
irregular tortuous lesions that may be local or
diffuse. Localized symptomatic neurofibromas can
be excised and the diffuse tumors can be managed
by periodic partial excision.
Juvenile xanthogranuloma
Juvenile xanthogranuloma is an idiopathic
cutaneous eruption of childhood in which
conjunctival involvement is very rare. Most
reported conjunctival cases have been in adults
without skin lesions. They present as solitary,
elevated conjunctival lesions near the corneoscleral
limbus. They are usually round or yellow/fleshcolored masses. Histopathological examination
reveals lipid histiocytes, chronic inflammatory
cells and the characteristic Touton giant cell.
Most conjunctival lesions have been excised in
order to establish the diagnosis. However, they
may spontaneously involute or respond to topical
steroids.
Fig.7 Conjunctival nevus. (A) Small circumscribed
pigmentation of the conjunctiva which does
not require active surgical intervention. (B) An
aggressive looking nevus with suspicious feeder
vessels in the superior aspect. This lesion warrants
surgical excision and regular follow-up.
14
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epithelium. Compound nevi extend into the
substantia propria, but maintain an intraepithelial
component. They may develop cystic areas because
of entrapment of goblet cells. The subepithelial
type eventually loses its connection with the basilar
epithelium and is confined within the substantia
propria.
Nevus of Ota
In this condition, conjunctival or scleral
pigmentation (slate-gray or bluish in color) is
associated with pigmentation of the periocular
tissue as well as the face. The nevi are present at
birth. Patients with this condition are at increased
risk for developing a uveal melanoma or glaucoma.
Melanocytic nevus
This is a rare form of congenital nevus that
involves the eyelid skin, conjunctiva, and the
face (Fig.8). The surface is jet black, hairy, and
often nodular. It carries a high risk of malignant
transformation, which is estimated to be as high as
45%. Radical excision and reconstructive surgery
is the usual treatment.
Malignant melanoma
This condition is rare in children. Conditions
such as dysplastic nevus syndrome, xeroderma
pigmentosa, and neurofibromatosis put children
at increased risk of developing a malignant
melanoma. It is characterized by a rapid growth
of pigmented lesions of the conjunctiva, and
feeder vessels may be seen. Involvement of Tenon's
capsule and the sclera may restrict the mobility of
the tumor over the ocular surface. In suspected
cases it is important to check the preauricular and
submandibular node for enlargement.
Miscellaneous disorders of conjunctiva
Pyogenic granuloma
An aberrant healing response following trauma or
surgery for strabismus can result in an exaggerated
fibrovascular response, erroneously referred to as
pyogenic granuloma. However, this condition is
neither an infection nor a typical granulomatous
reaction, but a granulation tissue formation.
Rapid growth may simulate a malignancy. A
history of preceding trauma or surgery helps in
making the diagnosis. The condition may resolve
spontaneously, but usually some form of treatment
is required. A short course of topical steroids may
be given, but excision biopsy is the treatment of
choice.
Fig. 8 Giant melanocytic nevus. (A) Affecting the
left half of the face along with pigmentation of the
left eye. (B) A close-up view of the left eye showing
dense pigmentation of the conjunctiva more on the
nasal half. The surrounding skin of the eyelids also
shows dark pigmentary changes.
Subconjunctival hemorrhage
A subconjunctival hemorrhage often occurs after
a seemingly trivial blunt trauma (Fig. 9). It can
also be seen in conditions which cause a rise in
central venous pressure such as a seizure, violent
coughing, or sudden straining. It may present in
a dramatic manner and may cause considerable
consternation. It usually resolves spontaneously
Vol. XVI, No.2, April - June 2016
15
Fig. 10 An elevated nodular lesion seen in a 7-yearold girl on anti-tuberculous treatment.
Fig.9 Subconjunctival hemorrhage following a fist
injury to the eye. An associated ecchymosis of the
lower lid is also seen.
within 2 weeks and does not require any treatment.
Subconjunctival hemorrhages are also seen in
conditions such as leukemia and as a sequelae to
some forms of conjunctivitis. In cases of suspected
head injury, the presence of a subconjunctival
hemorrhage with a poorly defined posterior
margin is a matter of grave concern and has to be
investigated radiologically.
Conjunctival granulomas
The presence of a variety of lymphoid cells in the
substantia Propria serves as a perfect setting for
the development of inflammatory granulomas
following some systemic and local disorders,
The common systemic diseases that can cause
conjunctival granulomas include sarcoidois,
tuberculosis, Parin-iud's oculoglandular syndrome,
Wegener's granulomatosis, trematode-induced
granulomas, and rhinosporidiosis. Sarcoid nodules
manifest as small light brown colored nodules in
the conjunctiva and show aggregates of epitheioid histiocytes on histopathological evaluation.
Tuberculosis of the conjunctiva may cause
granulomas, tarsal necrosis, conjunctival masses,
and small miliary palperal conjunctival ulcers.
Phlyctenular conjunctival response can also be
seen in some cases (Fig.10). Coexisting anterior
segment involvement may be present.
Fig. 31.11 River water granuloma. Well-circumscribed smooth elevated nodular lesion seen in the
bulbar conjunctiva. (Courtesy of Dr. Rathinam, DNB)
Trematodes are known to cause conjunctival
granulomas. They are acquired by children while
swimming in fresh water ponds infested by these
trematodes. The granuloma is usually seen as a
smooth, enlarged nodular lesion in the bulbar conjunctiva (Fig.11). Coexistent anterior chamber
granuloma and corneal inflammation may be seen
in some cases. A specific inflammatory reaction
known as Splendore-Hoeppli phenomenon
has been described with helminthic infections,
though the helminths themselves have rarely
been isolated. The reaction comprises a central
deposit of granular, acellular eosinophilic material
surrounded by eosinophils, epithelioid cells,
histiocytes. and lymphocytes. Small granulomas
may be treated with topical corticosteroids.
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Fig.12 Rhinosporidiosis. Pedunculated irregular
granuloma seen in the inferior palpebral conjunctiva.
Note the white spherules over the surface of the
granuloma. (Courtesy of Dr. Usha Kim, DNB.)
Fig. 13 Cysticercosis ofthe conjunctiva. A
subconjunctival translucent cyst in the bulbar
conjunctiva caused by cysticercosis.
Large lesions and those that fail conservative
management should undergo an excisional biopsy.
Rhinosporidiosis may present as pedunculated
granulomas, often seen in the palpebral conjunctiva
(Fig.12). The surface is granular and on careful
examination reveals pearly white studded spores,
which have a tendency to bleed on touch.
Treatment is by complete excision followed by
cryotherapy. This lesion has an extraordinary
tendency to bleed during surgery.
Ophthalmia nodosa is a granulomatous
nodular conjunctivitis caused by irritation of the
eye due to retained capillary hairs of caterpillars,
spiders, or bees. Children presenting with this
condition often give a history of a fall. Small
nodules may be seen in the conjunctiva along
with patterned corneal abrasions. These corneal
abrasions are due to the hairs embedded in the
upper tarsus and their sharp ends rubbing the
cornea.
subconjunctival in location with a thin translucent
wall (Fig.13). Adjacent orbital structures and
muscles may be involved. A chalky white area
representing the scolex may be seen which clinches
the diagnosis. Spontaneous expulsion of these cysts
has been reported. A complete ophthalmic and
systemic evaluation is needed to look for other
involved areas. Treatment is by mechanical removal
with supplementation of systemic antihelminthic
treatment. Exuberant inflammatory responses may
need a course of systemic steroid therapy.
Parasitic infestation of the conjunctiva
This condition is common in endemic areas and
usually presents in the cyst form. The common
parasitic cysts are cyst-icercus and hydatid. They
may present with inflammation. These parasitic
cysts have to be removed in toto along with
cryotherapy of the base. Cysticercosis is caused
by the larval form of Taenia solium known as
cysticercosis cellulosae. The cysts are usually
Ophthalmomyiasis
This term refers to the infestation of the eye by
the larval forms of the order Diptera. Implicated
species include Oestrus ovis (transmitted
from sheep and goats by gravid adult flies),
Dermatolabia hominis. (transmitted from cattle
and fowl by mosquitoes, such as Cuterebra,
Hypoderma bovis, chng somyia and cordylobia).
Conjunctival involvement causes irritation,
foreign body sensation, redness, and chemosis. There may be
pseudomembrane formation with petechial
hemorrhages. Patients may experience perception
of movements and slit-lamp examination shows
the larvae. The aim of the treatment is to extract
the worm mechanically. The worm may be caught
with a forceps or pulled out with a suture passed
through the larva.
Vol. XVI, No.2, April - June 2016
17
Fig. 14 Subconjunctival worm. The contour of this
worm, identified later as Filaria, is clearly seen.
Fig.15 Subconjunctival foreign body. A small
twig embedded in the conjunctiva and required
mechanical removal.
Occasionally, adult worms can be seen
presenting in the subconjunctival space with the
patient complaining of irritation and foreign body
sensation. A slit-lamp evaluation will reveal the
contours of the worm (Fig.14). The treatment
by mechanical removal of the worm using a
forceps. In some instances, the worm is entrapped
beneath the conjunctiva in close proximity to
the extraocular muscles. In these situations, care
should be taken to isolate the muscle and extract
the worm without injuring the muscle.
anteriorly into the subconjunctival space and may
present as a cystic lesion beneath the conjunctiva.
Thi s condition, which may mimic a subconjunctival
cyst, is referred to as a phacocele (Fig.16), which
may also be a presenting sign of Ehlers-Danlos
syndrome type 6.
Conjunctival trauma and foreign bodies
The conjunctiva is a common site for foreign
bodies, most commonly upper tarsal. An
examination after lid eversion is mandatory for any
history of trauma and suspicion of foreign body.
Various foreign bodies that have been described
include insect wings, beetles, cilia, caterpillar
hair, seed husk, pieces of wood, twigs (Fig.15),
and natural and synthetic fibers. Any foreign
body lodged in the conjunctiva evokes an acute
inflammatory reaction with a copious outpouring
of tears. However, if the foreign body has a large
surface area, it may become embedded resulting
in a chronic inflammatory response. This causes
a granuloma containing epithelioid and foreign
body giant cells. The symptoms rapidly abate after
the removal of the foreign body. Very rarely, blunt
injuries in the eye, especially in older children
and young adults, can cause the lens to dislocate
Symblepharon
In this condition, there is an adhesion between the
bulbar and palpebral conjunctiva. It commonly
occurs in association with congenital lid coloboma.
Other causes include a chronic dry eye, chemical
burns, and Stevens-Johnson syndrome where the
goblet cells are destroyed. Localized symblepharon,
without compromise to the visual apparatus,
need not be treated. Surgical release and forniceal
reconstruction using amniotic membrane or
mucous membrane grafts is indicated in severe
cases.
Fig.16 Phacocele. A traumatically anteriorly
dislocated lens mimicking a subconjunctival cyst.
18
AECS Illumination
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