Episclera and Sclera

Question 1

What is the composition of the scleral stroma?

Answer 1

Collagen bundles varying size and shape not uniformly orientated as in the cornea so are not transparent.

Question 2

What are the 3 pre-equatorial vascular layers of the sclera?

Answer 2

Conj vessels- superficial. Arteries tortuous veins straight

Superficial episcleral plexus- straight vessels with radial configuration. In episcleritis, max congestion occurs at this level. Topical pheny 2.5% will constrict conj and 10% superficial episcleral vessels

Deep vascular plexus- superficial part of sclera shows max congestion in scleritis. Purplish hue is characteristic

Question 3

What is Episcleritis?

Answer 3

Common idiopathic and benign recurrent frequently bilateral condition.
Females>males.
Average patient middle aged
Self limiting lasts few days upto 3 weeks but rarely longer.

Question 4

What are some systemic associated conditions with episcleritis?

Answer 4

Dry eye
Rosacea
CL wear
Collagen vascular disorders eg RA, HZO, Crohn’s disease

Question 5

What proportion of cases does simple episcleritis account for?

Answer 5

accounts for 75% of cases. It tends to recur (60%), decreasing in frequency with time. Features often peak
within 24 hours, gradually fading over the next few days

Question 6

What are the symptoms and signs of simple episcleritis?

Answer 6

*Symptoms. Discomfort ranges from absent (up to 50%) to moderate. Grittiness is common and photophobia may occur.

*Signs. More than half of cases are simultaneously bilateral.
○Visual acuity is normal.
○Redness may be sectoral (two-thirds) or diffuse. Often it has an interpalpebral distribution, in a
triangular configuration with the base at the limbus.
○Chemosis, ocular hypertension, anterior uveitis and keratitis are all rare.

Question 7

What is the treatment for simple episcleritis?

Answer 7

Mild- no tx required. Cool compress/ artificial tears can be helpful
Weak steroid QDS for 1-2 weeks is sufficient or more potent steroid with rapid tapering.
PO NSAID occasionally required eg ibuprofen 200mg TDS.

Question 8

What are the signs and symptoms of nodular episcleritis?

Answer 8

Symptoms- red eye on waking. Over 2-3 days redness enlarges becomes uncomfortable
Signs- attacks clear without treatment but last longer than simple episcleritis
Tender red vascular nodule within the interpalpebral fissure. More than one focus may be present
Underlying flat anterior scleral surface on slit lamp indicating absence of scleritis
IOP occasionally elevated
AC rxn may be present but uncommon (10%)
After several episodes, inflamed vessels permanently dilated
Exclude phylcten or conj granuloma

Question 9

How to treat nodular episcleritis?

Answer 9

Same as simple episcleritis

Question 10

What is scleritis?

Answer 10

uncommon condition characterized by oedema and cellular infiltration of the entire thickness of the sclera. Immune-mediated (non-infectious) scleritis is the most common type and is frequently associated with an underlying systemic inflammatory
condition, of which it may be the first manifestation

Question 11

What are the signs and symptoms of diffuse anterior non-necrotizing scleritis?

Answer 11

Common in females present in 5th decade:
Symptoms- ocular redness progressing to pain that radiates to face and temple. Discomfort wakes patient up in early morning improves later in the day. Respond poorly to common analgesia. May be blurry vision

Signs-vascular congestion and dilation associated with oedema. Redness may be generalised or localised to one quadrant. Secondary features include chemosis, eyelid swelling, anterior uveitis and raised IOP

Question 12

Why does the sclera become grey/blue after scleritis?

Answer 12

increased scleral translucency. This is due to rearrangement of scleral fibres rather than a decrease in scleral thickness.

Question 13

What is the prognosis of diffuse anterior non-necrotizing scleritis?

Answer 13

The average duration of disease is around 6 years, with the frequency of recurrences decreasing after the first 18 months. The long-term visual prognosis is good.

Question 14

What are the signs and symptoms of Nodular anterior non-necrotizing scleritis?

Answer 14

Symptoms- insidous pain onset followed by increasing redness, globe tenderness and appearance of scleral nodule. Vision often reduced.

Signs- scleral nodules single or multiple in interpalpebral region close to limbus. Deeper blue red colour than episcleral nodules and immobile.
Slit lamp beam shows elevated anterior scleral surface
Multiple nodules may expand and coalesce if treatment delayed
10% phenylephrine drops constrict conj and sup episcleral plexus but not deep plexus overlying nodule.
Once inflammation in nodule subsides increased scleral translucency apparent

Question 15

What percentage of patients with Nodular anterior non-necrotizing scleritis develop necrotizing disease?

Answer 15

> 10%

Question 16

What is the classification of Immune- Mediated (Non- infectious) Scleritis?

Answer 16

Anterior
*Non-necrotizing
*Diffuse
*Nodular
*Necrotizing with inflammation
*Vaso-occlusive
*Granulomatous
*Surgically induced (can also be infective)
*Scleromalacia perforans (necrotizing without
inflammation)

Posterior

Question 17

What is Anterior necrotizing scleritis with inflammation?

Answer 17

the aggressive form of scleritis. The age at onset is later than that of non-necrotizing scleritis, averaging 60
years. The condition is bilateral in 60% of patients and unless appropriately treated, especially in its early stages, may result in severe visual morbidity and even loss of the eye.

Question 18

What are the symptoms and signs of Anterior necrotizing scleritis with inflammation?

Answer 18

Symptoms- gradual pain onset becoming severe and persistent radiating to temple, brow, jaw.

Signs-Varies according to stage:
Vaso-occlusive- associated with RA. Isolated patches of scleral oedema overlying non perfused episclera and conj seen. Patches coalesce and if unchecked rapidly proceed to scleral necrosis
Granuloma formation- in conjunction with GPA and polyarteritis nodosa. Starts with injection adjacent to limbus then extend posteriorly.
Surgically induced scleritis within 3 weeks of a procedure. Induced by strab repair, trab with excessive mitomycin exposure, pterygium excision or scleral buckling. Necrotizing process starts at surgical site and extend outwards

Question 19

How to investigate Anterior necrotizing scleritis with
inflammation?

Answer 19

*ESR, CRP, FBC, ANCA, ANA, ACCP, Lyme serology, syphilis, hepatitis B surface antigen, antiphospholipid antibodies.
*Radiological imaging- chest, sinus, joint. Consider TB, Sarcoid, Churg Strauss syndrome, Ank spond, GPA
*Angiography- FFA of anterior segment to distinguish necrotizing disease by presence of non perfusion and for monitoring.
*USS- for posterior scleritis
*Biopsy- in resistant cases and if infection suspected

Question 20

What is the pattern of occlusion in inflammatory vs scleromalacia perforans?

Answer 20

predominantly venular in inflammatory disease and mainly
arteriolar in scleromalacia perforans

Question 21

What are some complications of anterior scleritis?

Answer 21

*Acute infiltrative stromal keratitis- localised or diffuse
*Sclerosing keratitis- chronic thinning and opacification in which peripheral cornea adjacent to site of scleritis resembles sclera
*PUK- progressive melting and ulceration. In granulomatous scleritis, destruction extends from sclera into limbus then cornea. Seen in GPA, polyarteritis nodosa, relapsing polychondritis.
*Uveitis may denote aggressive scleritis
*Glaucoma- most common eventual cause of vision loss. IOP very difficult to control
*Hypotony- rarely phthisis may be result of ciliary body detachment, inflammatory damage or ischaemia
*Scleral perforation alone from inflammatory process is rare

Question 22

What is scleromalacia perforans?

Answer 22

(5% of scleritis) is a specific type
of progressive scleral thinning without inflammation that typically affects elderly women with longstanding rheumatoid arthritis, but has also been described in association
with other systemic disorders.

Question 23

What are the symptoms and signs of scleromalacia perforans?

Answer 23

Symptoms- mild non specific irritation . Absent pain, vision unaffected. Keratoconjunctivitis sicca suspected

Signs- Necrotic scleral plaques near limbus without vascular congestion
Coalescence and enlarged necrotic areas
Slow progression of scleral thinning with underlying uvea exposed

Question 24

How to treat Scleromalacia Perforans?

Answer 24

*Effective in early disease, not so much in late disease.
*No benefit from any agent useful. *Frequent lubricants, immunosuppressives, biologica have been used.
*Treat underlying disease
*Protect from trauma
*Surgical repair of scleral perforation eg patch grafting to prevent phthisis bulbi

Question 25

What is posterior scleritis?

Answer 25

a potentially blinding condition in which diagnosis is commonly delayed, with an adverse prognostic effect.
The inflammatory changes in posterior and anterior scleral disease are identical and can arise in both segments simultaneously or separately. The age at onset is often less than 40 years. Young patients are usually otherwise healthy, but about a third over the age of 55 have associated systemic disease.

Question 26

What are the symptoms and signs of posterior scleritis?

Answer 26

Symptoms- pain out of proportion to severity of inflammation but more severe in patients with accompanying orbital myositis. Photophobia not a dominant feature
Signs- choroidal folds confined to posterior pole and orientated horizontally. Exudative RD in 25%, Yellow brown exudative material mistaken for choroidal tumour.
Uveal effusion with choroidal detachment may be a feature. Disc oedema with drop in VA common caused by spread of inflammation to optic nerve and orbital tissue.
Myositis common giving diplopia, pain on eye movement, tender to touch and redness around muscle insertion. proptosis mild associated with ptosis

Question 27

What are radiological findings in posterior scleritis?

Answer 27

*Ultrasonography may show increased scleral thickness, scleral nodules, separation of Tenon capsule from sclera, disc oedema, choroidal folds and retinal detachment. Fluid in the Tenon space may give a characteristic ‘T’ sign, the stem of the
T being formed by the optic nerve and the cross bar by the fluid-containing gap.

*MR and CT may show scleral thickening and proptosis.

Question 28

Important systemic associations of scleritis?

Answer 28

RA
GPA
Relapsing polychondritis
polyarteritis nodosa
Crohn disease

Question 29

What is the most common systemic association of scleritis?

Answer 29

RA

Question 30

What are some facts about RA?

Answer 30

Presents in 3rd decade joint swelling usually hands.
Commoner in females>males
RF autoantibodies present in 80-90%.
More aggressive clinical course when no systemic association found.
Other ocular manifestations- keratoconjunctivitis sicca, ulcerative keratitis

Question 31

What are some facts about GPA?

Answer 31

Wegener graulomatosis an idiopathic multisystem granulomatous disorder characterized by small vessel vasculitis affecting paranasal sinuses, lower respiratory tract, kidneys and skin. Males>females affected. Presents in 5th decade.
cANCA found in >90% patients with active disease. Scleritis rapidly progressive, necrotizing and granulomatous
Other ocular manifestations are PUK, occclusive retinal vasculitis, orbital inflammatory disease, NLDO, Dacryocystitis

Question 32

What are some facts about Relapsing Polychondritis?

Answer 32

Idiopathic condition characterized by small vessel vasculitis involving cartilage resulting in recurrent progressive inflammatory episodes with multiple organ systems eg ears, nasal cartilage, respiratory system, heart and joints.
Presents in middle age. Scleritis intractable and can be necrotizing/ non necrotizing.

Question 33

What are some facts about polyarteritis nodosa?

Answer 33

An idiopathic aneurysmal vasculitis
affecting medium-sized and small arteries. Presentation is in the third to sixth decades, often with constitutional symptoms. The
male:female ratio is about 3:1. Ocular involvement may precede systemic manifestations by several years. About one-third of patients have hepatitis B infection. Scleritis is often aggressive and necrotizing. PUK, orbital pseudotumour and occlusive retinal periarteritis are other reported ocular features.

Question 34

What are some facts about Crohn’s disease?

Answer 34

a chronic, relapsing inflammatory bowel disease of unknown cause. Extraintestinal complications occur frequently during the course of the disease. The commonest of these are
peripheral arthritis and erythema nodosum. The eye is involved
in 4% to 10% of patients and a wide spectrum of inflammatory
conditions may be found. Acute episcleritis, acute anterior uveitis
and marginal keratitis are the commonest manifestation.

Question 35

What is the treatment for immune mediated scleritis?

Answer 35

Topical steroid
Systemic NSAIDS
Periocular steroid injection in non necrotizing disease
Systemic steroids when NSAIDS inappropriate/inadequate. IV methylpred in severe cases
Immunosuppressive/ immunomodulatory agents if control incomplete with steroids alone, as a steroid sparing measure in long term treatment, treat underlying systemic disease.
In necrotizing disease rituximab effective.

Question 36

What is Porphyria and what are the associations with scleritis?

Answer 36

Scleritis is a rare complication of congenital erythropoietic porphyria and two of the adult forms of porphyria: porphyria variegata and porphyria cutanea tarda. Overproduction and excessive storage of porphyrins occur in the liver. These highly photoactive chromophores are also deposited in the dermis and
sclera, which are subsequently stimulated by exposure to the sun.
The sclera becomes thin or excavated over a sharply demarcated area localized to the sun-exposed interpalpebral region adjacent to
the cornea. Acute diffuse anterior scleritis and posterior scleritis may occur. Patients should avoid sunlight and undergo phlebotomy.

Question 37

What are some causes of infective scleritis?

Answer 37

Herpes Zoster- most common infective cause. Necrotizing scleritis resistant to treatment resulting in thinned/ punched out area
TB scleritis rare and difficult to diagnose. Sclera may be infected from conj/choroidal lesion more common haem spread. involvement nodular/ necrotizing.
Leprosy
Syphilis- diffuse anterior scleritis in secodnary syphilis and scleral nodules may be a feature of tertiary syphilis
Lyme disease
Others eg fungi, pseudomonas, Nocardia

Question 38

What is the treatment for infective scleritis?

Answer 38

Treat infective cause. Topical/ systemic steroid used to reduce inflammatory reaction. Surgical debridement can debulk a focus of infection facilitating penetration of antibiotics

Question 39

What is Alkaptonuria?

Answer 39

autosomal recessive condition,
a defect in homogentisic acid oxidase results in the accumulation of homogentisic acid in collagenous tissues such as cartilage and tendon (ochronosis). Ocular manifestations include bluish-grey or black generalized pigmentation of the sclera and the tendons of horizontal recti associated with discrete pigmented globules. Systemic features include dark urine and arthropathy.

Question 40

What is Haemochromatosis?

Answer 40

systemic features of haemochromatosis are caused by
increased iron deposition in various tissues. Features may be more subtle than the classic triad of a bronze complexion, hepatomegaly and diabetes. Inheritance is autosomal recessive. Dry eye and rusty-brown perilimbal conjunctival and scleral discoloration may develop

Question 41

What is the pathogenesis of blue sclera?

Answer 41

Blue scleral discolouration is caused by thinning or transparency with resultant visualization of the underlying uvea

Question 42

What is Osteogenesis imperfecta?

Answer 42

an inherited disease of connective
tissue, usually caused by defects in the synthesis and structure of
type 1 collagen. There are multiple types, at least two of which have
ocular features

Question 43

What is Type 1 OI?

Answer 43

autosomal dominant. Patients suffer few fractures with little or no deformity, hyperextensible joints, dental hypoplasia, deafness and easy bruising. Possible ocular features include blue sclera, megalocornea and corneal arcus.

Question 44

What is Type 2A OI?

Answer 44

sporadic or inherited in an autosomal
dominant manner. Systemic features include deafness, dental anomalies, multiple fractures and short
limbs, with death in infancy from respiratory infection.
Ocular manifestations include blue sclera and shallow orbits.

Question 45

What is Ehlers- Danlos Syndrome Type VI?

Answer 45

(ocular sclerotic) is an inherited
disorder of collagen formation. Patients have thin and hyperelastic
skin that bruises easily and heals slowly.
six major types but type VI and, rarely, type IV, are associated with ocular features. As well as blue sclera, other manifestations include scleral fragility
(globe rupture may be caused by mild trauma), epicanthic folds,microcornea, keratoconus, keratoglobus, ectopia lentis, myopia and retinal detachment

Question 46

What is Congenital Ocular Melanocytosis?

Answer 46

uncommon condition characterized by an increase in number, size and pigmentation of melanocytes in the sclera and uvea. The periocular skin, orbit, meninges and soft palate may also be involved

Question 47

What is Ocular Melanocytosis?

Answer 47

least common, involves only the eye. Multifocal slate-grey pigmentation is seen within the sclera and episclera- the process does not involve the overlying conjunctival layers, unless there is incidental conjunctival pigmentation. The overlying conjunctiva is mobile over the episcleral pigmentation but the pigmentation itself is intrinsic and cannot be moved over the globe. The
peripheral cornea is occasionally involved.

Question 48

What is Oculodermal melanocytosis (Naevus of Ota)?

Answer 48

the most common type and involves both skin and eye. Naevus of Ota
is bilateral in 5%. It occurs frequently in darker-complexioned races but is rare in white people. There is deep bluish hyper- pigmentation of the facial skin, most frequently in the distribution of the first and second trigeminal divisions

Question 49

What are the associations of congenital ocular melanocytosis?

Answer 49

*Iris hyperchromia
*Iris mammillations uncommon- tiny regularly spaced viteliform lesions. *Also seen in Axenfeld- Riger and Peter anomaly, NF-1
*Fundus hyperpigmentation
*Trabecular hyperpigmentation causing glaucoma
*Uveal melanoma in small minority

Question 50

What are the signs of Idiopathic sclerochoroidal calcification?

Answer 50

Age-related condition that usually involves both eyes of an affected older adult.

*Signs. Geographical yellow–white fundus lesions with ill- defined margins, often multiple and located in the superotemporal or inferotemporal mid-periphery associated with the vascular arcades.

Question 51

What does Ultrasonography of Idiopathic Sclerochoroidal Calcification show?

Answer 51

highly reflective choroidal plaque-
like lesions with orbital shadowing.

Question 52

What are some differentials for idiopathic sclerochoroidal calcification?

Answer 52

mainly from osseous metaplasia
associated with a choroidal haemangioma and from choroidal
osteoma, which is usually a single – though often large – lesion that usually (80–90%) involves only one eye.

Question 53

What are scleral hyaline plaques?

Answer 53

oval dark-greyish, generally sharply
demarcated, areas located close to the insertion of the horizontal rectus muscles