1. health and fitness
2. disease

Continuing Education & Training
Ahmed Sallam MD, FRCS and Susan Lightman PhD, FRCP, FRCOphth
Therapeutics in practice
Disorders of the sclera and episclera
nflammation of the sclera is an uncommon disease but it has
serious consequences if it is mismanaged. Episcleritis is also a
relatively uncommon disorder, which is not sight-threatening. This
article will detail the main types of scleritis and episcleritis,
describing the most common symptoms and signs, and treatment
strategies.
I
Inflammatory conditions
of the sclera
Episcleritis
Episcleritis is an acute, self-limiting, benign
inflammation of the loose connective tissue
lying superficial to the sclera (episclera).
Most cases are idiopathic. The
pathophysiology of episcleritis remains
unclear, but up to 30% of cases may be
related to an underlying systemic disease,
such as a collagen vascular disease
(rheumatoid arthritis, systemic lupus
erythematosus, polyarteritis nodosa, human
leukocyte antigen B27–associated
syndromes), rosacea, thyroid disease and
gout.
Enter answers online
at www.otcet.co.uk
CONFUSED ABOUT
CET REQUIREMENTS?
See www.cetoptics.com/
cetusers/faqs/
IMPORTANT INFORMATION
Under the new Vantage rules,
all OT CET points awarded will
be uploaded to its website by
us. All participants must
confirm these results on
www.cetoptics.com so that
they can move their points
from the “Pending Points
record” into their “Final CET
points record”. Full instructions
on how to do this are available
on their website.
2 standard CET points
Figure 1
Diffuse episcleritis. Note dilated blood vessels
with preservation of the normal radial pattern
of the episcleral vessels
1 CET point
Ocular manifestations/classification
Episcleritis is typically a transient, sometimes
recurrent disease of adults, usually 20 to 50
years of age. It is rarely seen in children. The
main presentation is an abrupt onset of
ocular redness in one or both eyes which
may be associated with minimal discomfort.
No pain is usually encountered. The disease
mostly occurs in the exposed part of the
sclera. Slight tenderness may be present at
the site of inflammation. Episcleritis is
recognisable in the anterior episclera as a
diffuse process (Figure 1) or less commonly
as a nodular form (Figure 2) where a white
inflammatory nodule is present within the
inflamed area. In this condition, there is
usually no corneal affection or anterior
chamber reaction and vision is usually
unaffected.
Differential diagnosis
Scleritis is a more serious condition. It is
defined as inflammation of the underlying
sclera and may also involve the overlying
episclera. Both conditions typically have
classic sectoral redness, while the rest of the
eye remains relatively unaffected. The
clinical differentiation of episcleritis and
scleritis involves a detailed history and a
careful ocular examination to determine
which layers of the wall of the eye are
involved by inflammation. Differentiation
is important at presentation as
management, prognosis, and complications
are very different for these two diseases and
long-term studies have shown that very few
patients progress from developing one to
the other.
Figure 2
Nodular episcleritis. Note a white inflammatory
nodule is present within the inflamed area and
the rest of the episclera is uninvolved
Diagnosis and ancillary testing
As 30% of the patients may have an
associated systemic disease which may have
not yet been identified, a careful review of
system’s history taking is appropriate.
Laboratory testing is rarely indicated in
patients with episcleritis except in cases
with multiple recurrences, or if there is
suggestive history of collagen vascular
disease.
Sponsored by
a
SPECIALISTS IN EYECARE
Module 8 Part 7
Therapeutics in
clinical practice
About the authors
Pathology
The histopathology of episcleritis is of
chronic non-granulomatous inflammation
with oedema limited to the episcleral tissue,
only rarely is the inflammation of a
granulomatous nature.
Treatment
Episcleritis is a self-limiting disease which
generally clears by itself. Most patients
only require reassurance. However, patients
Professor Susan Lightman is Head of
Department, Professor of Clinical
Ophthalmology and Consultant
Ophthalmologist at Moorfields Eye
Hospital and the Institute of
Ophthalmology, London.
Ahmed Sallam is a Clinical Fellow at
Moorfields Eye Hospital, working with
Professor Lightman. He was previously
Assistant Lecturer in Ophthalmology at
Ain-Shams University, Cairo, Egypt.
29 | July 1 | 2005 OT
a
Sponsored by
Continuing Education & Training
who are experiencing discomfort, may
benefit from topical lubricants or mild
topical steroids (e.g. Fluorometholone
0.1% to 0.25%). It is important to
remember that, although effective, topical
steroids should not be used on a
continuing basis as they may induce
potentially sight-threatening complications
such as cataract and glaucoma. More severe
or persistent cases, particularly of nodular
episcleritis, may require oral non-steroidal
anti-inflammatory drugs (NSAIDs) to quell
the inflammation.
Scleritis
Scleritis is typically a chronic and severe
painful inflammatory process centered in
the sclera, which may involve the cornea,
adjacent episclera, and underlying uvea.
The incidence of systemic disease in
patients with scleritis is reported in about
50% of cases. A large number of
connective-tissue disorders are associated
with scleral disease, such as rheumatoid
arthritis, systemic lupus erythematosus,
Wegener’s granulomatosis (a systemic
necrotising vasculitis affecting the
respiratory system and other organs) and
polyarteritis nodosa (a systemic necrotising
vasculitis, which characteristically affects
medium to small sized vessels). Other
associated systemic diseases include
inflammatory bowel disease, and gout.
Infectious cases of scleritis are reported
but are uncommon, particularly in the
absence of infectious keratitis, history of
accidental or surgical trauma to the eye, or
recurrent herpes simplex infection. The
most common infective causes are syphilis,
herpes simplex and zoster, and Pseudomonas
aeruginosa. Acanthamoeba can also be
implicated, particularly in contact lens
wearer.
Ocular manifestations
Scleritis occurs in all age groups but is most
common in middle aged and elderly
individuals, usually females. The onset of
scleritis is usually gradual, extending over
several days. Unilateral or bilateral
inflammation can occur. The characteristic
feature of scleritis is a severe dull boring
pain, which is often referred to as being in
the temple and jaw. This is usually
exacerbated by eye movement, and is worse
at night, often waking the patient in the
early hours. Some patients with scleritis,
however, have little or no pain because of a
partial effect from the use of NSAIDs drugs.
The patient with anterior scleritis usually
notices redness and tenderness of the globe.
There may be photophobia and
lacrimation. Patients with posterior scleritis
may present with reduced vision, with or
without pain. Patients may have an
underlying systemic disorder but not all do
and many remain healthy.
Scleritis occurs more commonly anterior
to the equator, because of the more
abundant anterior vascular supply. The
30 | July 1 | 2005 OT
circulation overlying the sclera includes
three vascular layers: 1) the conjunctival
plexus, the most superficial plexus of fine
vessels, which is movable over the
underlying structures; 2) the superficial
episcleral plexus, which consists of radially
arranged vessels lying at the level of the
Tenon’s capsule and 3) the deep episcleral
plexus, also known as the scleral plexus,
which lies deep to Tenon’s capsule and
directly over the sclera. The sclera itself is
avascular.
Scleritis is classified as either posterior
or anterior. Posterior scleritis is
characterised by scleral inflammation, often
with overlying uveitis confined to the
posterior portions of the globe, while
anterior scleritis can be either necrotising or
non-necrotising. Non-necrotising anterior
scleritis is further classified as either
nodular or diffuse. Most patients remain in
the same clinical category throughout the
course of their disease. Signs of scleritis
depend on the location of the scleritis and
its severity. The hallmark signs of scleral
inflammation are the development of
scleral oedema and dilatation or closure of
the deep episcleral vascular plexus.
Anterior scleritis is the most common
form of scleral inflammation. Maximum
dilatation and congestion occur in the deep
episcleral vascular plexus, with some
congestion in the superficial episcleral
plexus and the conjunctival plexus
(Figure 3). It can be localised to a patch of
the sclera or may involve the entire anterior
sclera. The globe is usually tender to touch.
A more localised area of scleral oedema
characterises nodular anterior scleritis such
that distinct nodules result. They may be
single or multiple and can become quite
prominent and tender to palpation
(Figure 4).
Necrotising anterior scleritis is the most
severe and destructive form of scleritis,
sometimes leading to loss of the eye from
multiple complications, severe pain, or
perforation of the globe. There is usually
severe pain and extreme scleral tenderness.
The scleral involvement is characterised by
severe vasculitis and closure of the
episcleral vascular bed which is seen as
white avascular areas with infarction and
necrosis of the involved sclera (Figure 5).
Scleromalacia perforans is a very rare
form of necrotising anterior scleritis,
which typically occurs in a patient with
long-standing rheumatoid arthritis. The eye
is typically painless and lacks the acute
clinical signs of necrotising scleritis. The
sclera is parchment white, avascular, and
thin. There may be exposure of the choroid
and staphyloma formation, especially if the
intraocular pressure is elevated. There may
be sequestra of infarcted sclera surrounded
by areas of thinning scleral tissue
(Figure 6). Spontaneous perforation is rare,
although these eyes may rupture with
minor trauma.
Posterior scleritis is inflammation of the
SPECIALISTS IN EYECARE
Figure 3
Diffuse anterior scleritis. Note the vascular
engorgement has a dark violaceous colour, with
loss of the normal radial pattern of the
episcleral vessels (pupil is dilated)
Figure 4
Nodular anterior scleritis. Note large
superior nodule and the rest of
the sclera is minimally involved
Figure 5
Necrotising anterior scleritis. Note large area
where the sclera is ulcerated and the overlying
conjunctiva and episclera are missing
Figure 6
Scleromalacia perforans. Note the superior
aspect of the sclera is white, avascular, and
thin, revealing the underlying choroid (blue
appearance)
sclera behind the insertion of the recti
muscles. This occurs in association with
anterior scleritis, or may be isolated. When
it occurs in isolation, the eye may look
a
Sponsored by
Continuing Education & Training
SPECIALISTS IN EYECARE
CET online
ONLINE INSTRUCTIONS
If you are GOC or Irish board registered, you can
enter your answers on-line at www.otcet.co.uk.
Enter your GOC/Irish board number, surname and
password to log onto the system. If you have
never used a password before on this web site,
please enter your GOC number and surname and
leave the password box entry blank, and then
click on the "Log In" button. A password is
required to keep personal information private.
Figure 8
Figure 7
B-scan ultrasound demonstrating posterior
scleritis. Note localised thickened area,
indicating area of posterior scleral swelling
Posterior scleritis. Note optic nerve oedema
and peripapillary cotton wool spots
white, and ultrasound remains the key to
diagnosing the associated thickening of the
posterior coats of the eye (Figure 7). The
posterior segment may appear normal, or
there can be a variety of signs, such as
choroidal detachment, serous retinal
detachment, macular oedema, optic nerve
swelling (Figure 8), retinal folds (Figure 9)
and subretinal mass.
Select from the appropriate prefix:
01- or 02- for optometrist
D- for dispensing optician
Irish- for Irish board registration
You will then arrive at the following screen unless you
have received notification to phone OT CET:
Differential diagnosis
Patients with anterior scleritis present with
a painful red eye, which must be
distinguished from other inflammatory
conditions such episcleritis, conjunctivitis,
keratitis or iritis.
Both diffuse and nodular episcleritis
must be differentiated from scleritis. The
patient with episcleritis never complains of
severe radiating pain. The eye has a distinct
red hue with preservation of the normal
radial pattern of the episcleral vessels and
the sclera is never oedematous. In scleritis,
the patient has severe pain and the vascular
engorgement has a violaceous blue colour,
with loss of the normal radial pattern of
the episcleral vessels. On slit lamp
examination, due to the scleral oedema, the
light beam is displaced forward.
Examination in natural daylight can be
extremely useful, allowing the detection of
these subtle colour differences, which are
often not appreciable using a slit-lamp.
With topical application of
phenylephrine, the eye will appear white in
the case of episcleritis, but not with scleritis
as the drug mainly affects the conjunctival
and superficial episcleral vessels, while the
deep vessels involved in scleritis are hardly
affected.
Although conjunctivitis is one of the
common causes of acute red eye, significant
ocular pain or tenderness is very
uncommon. Unlike scleritis, there is
usually conjunctival discharge as well as a
papillary or follicular response of the tarsal
conjunctiva.
Acute anterior uveitis may simulate
scleritis in its presentation with intense,
pain, photophobia, and reduced vision.
The presence of anterior uveitis in about
40% of scleritis cases adds more difficulty
to the diagnosis. Differentiating points
4
Figure 9
5
Posterior scleritis. Note retinal folds present in
the posterior pole
2
include the localisation of the vascular
engorgement mainly around limbus (ciliary
injection) as well as a significant anterior
chamber reaction (aqueous cells, flare and
possibly hypopyon) in anterior uveitis
cases.
The diagnosis of corneal ulcer is usually
suspected with a history of ocular trauma
or contact lens wear. The presence of a
corneal infiltrate with an overlying
epithelial defect, which takes up fluorescein
dye, confirms the diagnosis.
Acute closed angle glaucoma is usually
associated with a more acute presentation
than scleritis as well as a hazy cornea and a
semi-dilated pupil. The diagnosis is
comparatively straightforward once the
intraocular pressure is measured.
Since posterior scleritis can present with
proptosis, lid swelling, or limitation of
ocular movements, one must think about
inflammatory pseudotumor or thyroid
ophthalmopathy in the differential
diagnosis. With regards to subretinal
masses, it is mandatory to exclude
choroidal melanoma and choroidal
metastases. Fluorescein angiography
combined with B-scan ultrasonography
should help in the correct diagnosis.
Sometimes posterior scleritis can present as
a serous detachment of the choroid, ciliary
body or retina. In these cases, it must be
differentiated from uveal effusion
syndrome, Vogt-Koyanagi-Harada disease,
central serous retinopathy or sympathetic
ophthalmitis when there has been a history
of intraocular surgery or penetrating
trauma.
3
1
1
Credit – This is for “Pay-As-You-Learn”
articles only. This article does NOT require
any credit, but you can purchase £60 of
credit for our “Pay-As-You-Learn” series by
calling 01252-816266 with debit card details).
2
Take Exams - Select the examination you want
to enter from those available. It is important
that you choose the right exam and do not
enter your answers into any other available
examinations running at the same time as you
will not be able to go back to try again. Any
errors made by participants cannot be
recalled. Enter your answers, and an optional
email address if you want email notification
of your results and press the ‘send answers’
button. The next screen will show your
percentage and any CET points gained.
3
Grade Book - This area will keep track of
your previous exam results. It is strongly
advised that you keep an independent paper
record of all your CET scores from all sources
including OT as you will have to use this
information to claim your CET points at the
year end.
4
Amend Details - This will alter the address
where posted correspondence from OT CET
will be sent. If you choose to do a paper
entry at some time, this will be the address
our marked reply sheet goes to. Your email
address entered into the website will not be
passed onto third parties and will only be
used for the purpose of OT CET.
5
Important Notices - Watch this area for CET
announcements for example any planned
website maintenance outages.
If you require further assistance,
call 01252-816266
31 | July 1 | 2005 OT
a
Sponsored by
Continuing Education & Training
Diagnosis and ancillary testing
Evaluation of adjacent structures should
always be performed, as scleritis can be
associated with a myriad of sight
threatening ocular complications.
Peripheral ulcerative keratitis may be
seen in cases of necrotising scleritis
(Figure 10) associated with systemic
vasculitis or infective aetiology, and may
lead to corneal perforation. Central corneal
perforation is more likely to be due to dry
eyes associated with rheumatoid arthritis.
All types of scleritis can be associated with
uveitis, which may be mild or severe.
Anterior uveitis occurs in up to 40% of eyes
with scleritis and is more common with
severe scleritis, most often seen in
association with necrotising disease.
Glaucoma is a well known complication
of scleritis and may either be due to open
angle or angle closure mechanisms. Open
angle glaucoma may be secondary to
trabeculitis and raised episcleral venous
pressure. Angle closure mechanisms may
develop with massive serous retinal
detachment and anterior displacement of
the iris lens diaphragm, causing the
anterior chamber to become shallow and
close the angle or development of iris
bombé secondary to posterior synechiae. As
with any patient, a steroid response may
occur. The clue is that the intraocular
pressure was normal prior to the initiation
of steroid therapy, usually topically but
occasionally systemically, and became
elevated on treatment.
Cataract formation has been reported at
an incidence of about 15% in eyes with
scleritis. It usually develops some time after
the onset of scleritis and is related to both
the scleritis and long-term corticosteroid
therapy. Posterior segment complications in
cases of posterior scleritis include serous
retinal detachment, choroidal folds and
optic nerve swelling. Permanent visual loss
occurs in up to 30% of patients with
posterior scleritis, mainly due to the
development of optic atrophy or
irreversible macular changes.
Since patients with certain types of
scleritis, particularly the necrotising type,
have an increased rate of extra ocular
morbidity or mortality, its presence should
be recognised as a manifestation of a
potentially serious systemic disease. The
work-up should, therefore, include a careful
history, a detailed clinical examination and
a thorough review of systems, best
completed in conjunction with an
experienced physician or rheumatologist.
Laboratory tests should always be
guided by the history and physical
examination. Commonly used tests
include: complete blood picture,
erythrocyte sedimentation rate, renal
function as well as blood tests for
autoimmune diseases such as rheumatoid
factor, anti-nuclear antibodies and
anticytoplasmic antibodies. A chest X-ray is
usually needed mainly to exclude
tuberculosis, sarcoidosis and Wegener’s
granulomatosis. Ultrasonography may be
required in some patients with scleritis to
confirm the diagnosis of posterior scleritis.
The following ultrasonographic changes
can all be seen in posterior scleritis: scleral
and choroidal thickening, scleral nodules,
fluid in Tenon’s capsule, optic disc swelling,
distended optic nerve sheath, and retinal
detachment. In cases of suspected
infectious scleritis, conjunctival scrapings
for smears and cultures should be
obtained. If these are negative at 48 hours
and the scleritis continues to progress,
scleral or corneoscleral biopsy may be
required for diagnosis.
Pathology
The presence of T cells and macrophages
in deep episcleral biopsies from patients
with non-necrotising scleritis suggests that
T cells are the effector cell in scleritis, and
that the disease is more compatible with a
T cell mediated (autoimmune) disorder
rather than an immune complex reaction as
previously thought. Neutrophils and
granulomatous inflammation are also seen
in enucleated eyes with necrotising disease.
Treatment
Management of patients with scleritis is
challenging. Treatment almost always
SPECIALISTS IN EYECARE
Figure 10
Scleritis with cornea involvement as seen in
Wegener’s granulomatosis
requires systemic medication, as well as
co-management with a medical specialist
in the appropriate field to manage any
underlying systemic pathology.
Proper diagnosis and appropriate
immunosuppression may prove to be life
saving for those patients with disorders
such as Wegener’s granulomatosis. Urgent
referral to the ophthalmologist is
mandatory, particularly with the necrotising
type of scleritis or scleritis in contact lens
wearers as it may be infective.
For non-necrotising scleritis particularly
the diffuse type, systemic NSAIDs may be
effective and the cyclo-xygenase inhibitors
(Cox inhibitors) such as flurbiprofen or
ibuprofen are by far the most commonly
used class of drugs. The new Cox-2
inhibitors selectively inhibit the cycloxygenase isoenzyme induced at the sites of
inflammation without blocking the other
isoenzyme present physiologically.
Anecdotal experience with these agents
suggests that they are equally effective as
the non-selective Cox inhibitors. The lack of
gastrointestinal side effects is of great
benefit to patients, but they do have
significant cardiovascular risks and some
have been withdrawn.
Severe nodular scleritis and necrotising
disease require more aggressive antiinflammatory therapy. Treatment is usually
commenced with oral corticosteroids
starting with a high dose of 1mg/kg/day,
Start a revolution in dry feeling eyes
FORGET
DRYNESS
REMEMBER
SYSTANE.
Unique protection for immediate comfort and long lasting relief
32 | July 1 | 2005 OT
a
Sponsored by
Continuing Education & Training
SPECIALISTS IN EYECARE
which usually equates to 60-80mg/day in
adults. As the scleritis comes under control,
pain diminishes rapidly, together with
objective improvement in the signs of
scleral inflammation such as tenderness,
injection and scleral nodules which may
take months to resolve. In scleral necrosis,
blood flow improves in the episcleral
plexus and the area of necrosis stops
increasing in size. The induction phase of
therapy requires between two to eight
weeks, depending on the severity of scleritis
and the clinical response to treatment. The
next step is to begin to decrease the dosage
of corticosteroids and to consider
appropriate maintenance therapy to
consolidate the improvement in
inflammation achieved with induction
therapy and to minimise steroid related
complications. Patients usually need a
minimum of three to four months’
treatment before consideration is given to
withdrawing therapy.
Adjunctive systemic immunosuppressive
therapy is indicated in patients who have
severe scleritis, which is not controlled with
the use of high-dose oral or intravenous
corticosteroids or for inflammation, which
relapses at lower doses of prednisolone. A
large number of drugs have been shown to
be effective in the treatment of scleritis
and these include immunomodulators
(e.g. cyclosporine), anticytokines
(e.g. infliximab), antimetabolites
(e.g. methotrexate), or cytotoxic agents
(e.g. cyclophosphamide).
All patients receiving systemic
immunosuppressive therapy for scleritis
should be warned about the potential side
effects of the medications used. Systemic
NSAIDs may be associated with gastritis,
renal failure and bleeding as well as
worsening of pre-existing bronchial asthma
and the possibility of drug interactions,
particularly with anticoagulants.
Systemic steroids have serious side
effects such as hypertension, gastritis,
diabetes, psychosis, weight gain, aseptic
necrosis of the hip and osteoporosis in
long-term treatment. Patients who are more
susceptible to the side effects of
corticosteroids include the elderly,
diabetics, and patients with history of
gastrointestinal disease, tuberculosis or
bleeding disorders. Postmenopausal
females are particularly at high risk of
developing steroid-induced osteoporosis.
Strategies for decreasing corticosteroids side
effects include using the lowest possible
dose for the shortest duration and adopting
alternate day dosing, during maintenance
therapy if possible. In addition, patients
should be encouraged to exercise regularly,
decrease salt and fat intake and consider
calcium supplements and hormone
replacement therapy in postmenopausal
women to prevent osteoporosis.
Patients on long-term steroid therapy
are now given drugs such as didronel or
fosamax to reduce the steroid induced bone
loss. Second line immunosuppressive use
may be complicated with renal dysfunction
(cyclosporine), hepatitis (methotrexate),
bone marrow suppression, and an
increased risk of developing malignancy
(cyclophosphamide). Patients receiving
immunosuppressive therapy are at
increased risk of infection, especially
pulmonary infection. All patients, therefore,
should be encouraged to stop smoking,
avoid others with infections and remain up
to date with their immunisations.
Cases of infectious scleritis are very
resistant to treatment and up to 60% of the
eyes with infectious keratoscleritis may end
up with complete loss of vision or removal
of the eye, largely due to poor penetration
of antibiotics into the nearly avascular
sclera. Infectious scleritis caused by direct
spread of infectious keratitis has a worse
prognosis than isolated nodular infectious
scleritis. Numerous management options
have been described including topical
fortified antibiotics, subconjunctival
antibiotics, cryotherapy, lamellar or
penetrating corneoscleral graft, and
subpalpebral irrigation to allow for
continuous delivery of highly concentrated
antibiotics.
Indications for surgery in either
Q. When will my results show on the
Vantage CET website (www.cetoptics.com)?
A. If you obtain CET points for
this article, these will be
uploaded 10 days after July 27,
2005 (the closing date). You
need to confirm these points
on www.cetoptics.com and
move them from their ‘Pending
Points’ record to your ‘Final
Points’ record before 2006
under the GOC/Vantage rules.
infectious or autoimmune scleritis are
relatively infrequent. They include biopsy
for suspected infectious scleritis, as well as
repair of globe perforation, and repair of
uveal prolapse with impending perforation
in necrotising scleritis. Grafts can be made
of fascia lata, periosteum, split-thickness
dermis, or autologous or homologous
sclera. In cases of autoimmune scleritis,
which requires surgery for impending
perforation, this should only be
undertaken once adequate medical
immunosuppression is achieved. However,
emergency surgery for perforation is
required occasionally, even if optimal
immunosuppression could not be
achieved. Patients may also develop
cataract or glaucoma from trabecular
meshwork damage which requires surgical
treatment after the inflammation has
settled.
Non-inflammatory
conditions of the sclera
Epibulbar choriostomas
A hamartoma is a congenital tumour
resulting from abnormal tissue residing at
its normal site, as in the case of naevi and
haemangiomas. A choriostoma is a
congenital lesion which results from
normal tissue being placed in an abnormal
location during embryogenesis. The most
common episcleral choriostoma is a
dermoid. Others include dermolipomas,
osseous choriostomas and complex
choriostomas.
Limbal dermoids
Limbal dermoids are benign, generally
sporadic, congenital tumors which contain
choristomatous tissue. The exact
pathogenesis is unknown, but it may result
from sequestration of the pluripotential
cells (stem cells found in the bone marrow
which have the ability to differentiate into
any type of blood cell) during embryonic
development of the surrounding ocular
structures. They may contain a variety of
histologically aberrant tissues, including
epidermal appendages, connective tissue,
skin, fat, sweat gland, lacrimal gland,
muscle, teeth, cartilage, bone, vascular
structures and neurologic tissue, including
brain tissue. The lesion may be cystic or
solid and they usually have no malignant
potential.
Clinical presentation
The dermoid appears as a well
circumscribed, porcelain white, rounded to
oval lesion, which occurs most often at the
inferotemporal limbus with some
encroachment on the cornea. Fine hairs
may protrude from its surface. Corneal
astigmatism caused by a dermoid can lead
to anisometropic amblyopia. An estimated
30% of patients with limbal dermoids have
associated systemic abnormalities, which
include preauricular appendages and
33 | July 1 | 2005 OT
a
Sponsored by
Continuing Education & Training
auricular fistulae (Goldenhar’s syndrome).
Other abnormalities include microsomia,
microtia (a small, abnormally shaped or
absent external ear) and vertebral
anomalies.
Management
Surgical treatment should be instituted
only when the risk of subsequent scar
formation or surgical complications are
outweighed by the likelihood of improving
the patient’s vision or cosmetic appearance.
A superficial sclerokeratectomy is the
procedure of choice for removal of the
dermoid. Attempts at complete removal are
unnecessary as the lesion may extend into
the deeper structures of the eye and the risk
of perforation increases if attempts are
made to remove it completely.
Nanophthalmos
A small, functional eye with normal
internal organisation and proportions
characterises nanophthalmos. The
pathogenesis of this condition is unknown,
and both autosomal dominant and
autosomal recessive inherited patterns are
recognised.
Clinical presentation
Patients usually have a high degree of
hyperopia (+7 - +15 D), a thickened sclera
and crowded anterior segment structures
which may be associated with angle closure
glaucoma. Choroidal effusions are a serious
complication.
Management
Management is mainly directed towards
correction of hyperopia. Medical treatment
and peripheral laser iridotomy may be
effective and control associated glaucoma.
Anterior segment surgery may be
complicated by uveal effusion or
haemorrhage.
Microphthalmos
Microphthalmos is a small disorganised
eye. There is often an associated cystic
outpouching of the posteroinferior sclera.
The condition has been associated with
failure of the fetal fissure to close properly
and colobomatous defects of the uvea and
optic nerve are often present. The
pathogenesis of this condition is unknown,
and different inherited patterns are
recognised. Multiple associations have been
made with microphthalmos such as
maternal infections or exposure to
radiation and toxins as well as different
chromosomal trisomies (typically trisomy
13).
Clinical presentation
Associated ocular abnormalities include
leukomas, retina dysplasia, uveal
colobomas, persistent fetal vasculature, and
ptosis. Systemic associations are numerous
including mental retardation and dwarfism.
Management
Management is mainly directed towards
correction of associated conditions if
possible. Genetic counselling should also
be considered. A cosmetic shell may be
indicated in patients with blind
microphthalmic eyes.
Osteogenesis imperfecta
Osteogenesis imperfecta is a dominantly
inherited condition resulting from reduced
amounts of normal Type I collagen found
in bones, organ capsules, fascia, cornea,
sclera, tendons and dermis. The disease is
characterised mainly by bone fragility and
blue sclera due to generalised scleral
thinning, with increased visibility of
underlying uvea.
Clinical presentation
Patients usually present with bone fractures
SPECIALISTS IN EYECARE
from minor trauma in childhood,
kyphoscliosis, joint extensibility and
sometimes deafness.
Management
There is no effective treatment for this
condition. Cyclic administration of
intravenous pamidronate may reduce the
increased bone mineral density. Treatment
is mainly reserved for severe cases
presenting with marked osteopenia and
repeated fractures.
Conclusion
By taking a careful history and examining
the eye, episcleritis and scleritis can be
distinguished. Whereas episcleritis is
usually self-limiting, scleritis can be
extremely painful and when necrotising in
type is an ophthalmic emergency as the
integrity of the eye is at risk. Scleritis may
be the first feature of an underlying
potentially lethal disease and it is,
therefore, very important that it
is detected, investigated and treated
correctly.
Further reading
• McCluskey P (2001) Scleritis:
Fundamentals of clinical
ophthalmology, BMJ Books.
• Basic and Clinical Science Course
2004-2005: External Disease and
Cornea Section 8, American Academy
of Ophthalmology.
• Okhravi N, Odufuwa B, McCluskey P,
Lightman S: Scleritis. Survey of
Ophthalmology. In press.
• Albini T, Rao N, Smith R: The diagnosis
and management of anterior scleritis.
Int Ophthalmol Clin. 2005 Spring;
45(2):191-204.
MCQs
Module 8 Part 7 of Therapeutics in clinical practice – Disorders of the sclera and episclera
Please note: There is only ONE correct answer
1. Which one of the following
statements regarding episcleritis
is incorrect?
a. It is usually self-limiting
b. If not promptly treated, it often
progresses to scleritis
c. Periodic recurrences may occur
d. Patients usually have a good ocular
prognosis
2. Which one of the following
is NOT a feature of episcleritis?
a. Ocular redness
b. Ocular discomfort
c. Episcleral nodule
d. Anterior chamber cells and flare
3. Which one of the following would
not be considered in the treatment
plan for episcleritis?
34 | July 1 | 2005 OT
a. Topical lubricants b. Topical antibiotics
c. Topical steroids d. Systemic NSAIDs
4. Which one of the following statements
is correct regarding scleritis?
a. Most of the cases are idiopathic
b. The condition is self-limiting and
generally clears by itself
c. Laboratory testing is rarely indicated
d. Glaucoma is a known complication
5. Which one of the following
is not a feature distinguishing
scleritis from episcleritis?
a. Ocular hyperaemia
b. Deep boring ocular pain
c. Presence of scleral oedema
d. Lack of blanching of the vascular
congestion with topical phenylephrine
drops
6. Which one of the following diseases is
NOT associated with scleritis?
a. Rheumatoid arthritis
b. Wegener’s granulomatosis
c. Inflammatory bowel disease
d. Diabetes
7. Which one of the following is correct
regarding scleromalacia perforans
scleritis?
a. Scleromalacia perforans is seldom
associated with systemic disease
b. Sharp pain is characteristic
c. The sclera is usually markedly inflamed
and tender
d. The condition may be complicated by
staphyloma formation
Continued over
a
Sponsored by
Continuing Education & Training
SPECIALISTS IN EYECARE
MCQs
(cont)
Module 8 Part 7 of Therapeutics in clinical practice – Disorders of the sclera and episclera
Please note: There is only ONE correct answer
8. Which one of the following is
incorrect regarding posterior
scleritis?
a. Posterior scleritis always occurs in
association with anterior scleritis
b. The eye may sometimes look white
c. Thickening of the posterior coat of the
eye is diagnostic with ultrasonography
d. The condition may present with
proptosis or limitation of ocular
movements
9. Which one of the following is
incorrect about necrotising anterior
scleritis?
a. Infection is the most common
underlying aetiology
b. It is usually associated with severe
pain and extreme scleral tenderness
c. White avascular patches are seen
in the sclera
d. Ocular perforation may result if
treatment is not intensive and prompt
10. Which one of the following statements
is incorrect regarding the management
of scleritis?
a. Most cases require systemic treatment
b. Scleritis should be regarded as a
manifestation of a potentially serious
systemic disease
c. In necrotising scleritis, treatment is
usually commenced with oral NSAIDs
d. Tuberculosis and peptic ulcer disease
should be considered before starting
systemic steroids
11. Which one of the following statements
regarding limbal dermoids is correct?
a. Limbal dermoids can be considered
hamartomas
b. They usually present in adulthood life
c. Surgical removal carries a risk of ocular
perforation
d. They are not associated with systemic
abnormalities
12. Which one of the following
statements regarding nanophthalmos
is correct?
a. It is characterised by a small eye with
abnormal internal organisation and
proportions
b. It is typically associated with
colobomatous defects of the uvea and
the optic nerve
c. Patients usually have degenerative
myopia
d. Cataract surgery may be complicated by
suprachoroidal haemorrhage
An answer return form is included in this issue. It should be completed and returned to:
CET initiatives (c-135), OT, Victoria House, 178-180 Fleet Road,
Fleet, Hampshire, GU51 4DA by July 27, 2005.
Under no circumstances will forms received after this date be marked
– the answers to the module will have been published in our July 29, 2005 issue.
35 | July 1 | 2005 OT