Ophthalmology pdf - كتابة الطلاب

Important questions in Ophthalmology

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Chapter1: Anatomy

Q: What are the functions and components of eyelid?

Function:

1-  provide mechanical protection to the anterior globe.
2-  secrete the oily part of the tear film.
3-  spread the tear film over the conjunctiva and cornea



prevent drying of the eyes

4- contain the puncta through which the tears drain into the lacrimal drainage system.

Components:
  1- A surface layer of skin.
  2- The orbicularis muscle.
  3- A tough collagenous layer (the tarsal plate).
  4- An epithelial lining, the conjunctiva, reflected onto the globe.

Q: Write about tears production, composition, function, and drainage?

- Production =
By lacrimal gland in the upper lateral aspect of the globe, then it spread over the cornea
and conjunctiva by the movement of eyelid.
- Composition =



Thin mucin layer in contact with the ocular surface and produced mainly by the
conjunctival goblet cells.



Aqueous layer produced by the lacrimal gland.



Surface oil layer produced by the tarsal meibomian glands and delivered to the lid
margins.

- Functions =



it provides a smooth air/tear interface for distortion free refraction of light at the
cornea;



it provides oxygen anteriorly to the avascular cornea;



it removes debris and foreign particles from the ocular surface through the flow of
tears;



it has antibacterial properties through the action of lysozyme, lactoferrin and the
immunoglobulins, particularly secretory IgA.

- Drainage =
Tears drain into the upper and lower puncta  the upper and lower canaliculi  common
canaliculus  the lacrimal sac  nasolacrimal duct  the nose.

Q: What are the layers of cornea, and what are its function?

Layers:
 The epithelium, an anterior squamous layer thickened peripherally at the limbus where

it is continuous with the conjunctiva. The limbus houses its germinative or stem cells.

 An underlying stroma of collagen fibrils, ground substance and fibro- blasts. The regular

packing and small diameter of the collagen fibrils accounts for corneal transparency.

 The endothelium, a monolayer of non-regenerating cells which actively pumps ions and

water from the stroma to control corneal hydration and transparency.

Functions:
 It refracts light and together with the lens, focuses light onto the retina;
 It protects the internal ocular structures.

Q: Why cornea is transparent but sclera not, although both composed from
type II collagen?

- Collagen of cornea is fine, regular, uniform, arranged in layers, there are opens between
layers, small diameter of collage fibers …. But in sclera not like that.
- Level of hydration of cornea is not high (only 67%) but it is high is sclera.

Q: Write about attachment and detachment of the vitreous?

- Is firmly attached anteriorly to the peripheral retina, pars plana and around the optic disc,
and less firmly to the macula and retinal vessels.
- Detachment of the vitreous from the retina, which commonly occurs  in later life,
increases traction on the points of firm attachment, this may  occasionally lead to a
peripheral retinal break, when the vitreous pulls  away a piece of the underlying retina.

Q: Write about aqueous humour cycle?

- It is produced actively by the non-pigmented layer of paras plicata (ciliary process) to the
posterior chamber.
- Then the aqueous humour is travel from posterior chamber to the anterior chamber
through the pupil.
- Then it goes to the iridocorneal angle which is located between iris, cornea, and ciliary
body.
- Finally it drian through the Trabecular meshwork in the iridocorneal angle to the
Schlemm's canal, then to the venules then to extra-ocular veins.

Chapter3: Clinical optics

Q: What are the types of ametropia?

- Myopia (short sightedness); the optical power of the eye is too high  (usually due to an
elongated globe) and parallel rays of light are brought to  a focus in front of the retina.
- Hypermetropia (long sightedness); the optical power is too low (usually  because the eye
is too short) and parallel rays of light converge towards a  point behind the retina.
- Astigmatism; the optical power of the cornea in different planes is not equal. Parallel rays
of light passing through these different  planes are  brought to different points of focus.

Q: What are the advantage of gas permeable lenses?

  Their greater oxygen permeability reduces the risk of corneal damage from hypoxia.
  Their rigidity allows easier cleaning and offers less risk of infection.
  Their rigidity allows for a more effective correction of astigmatism.
  Proteinaceous debris is less likely to adhere to the lens and cause an allergic

conjunctivitis.

 Plane soft contact lenses may also be used as ocular bandages, e.g. in the treatment of

some corneal diseases such as a persistent epithelial defect.

Q: How you can correct presbyopia by spectacles?

- The correction of presbyopia requires additional lens power to overcome the eye's
reduced accommodation for near focus. This can be achieved with:
- Separate pairs of glasses for distance and near vision.
- A pair of bifocal lenses where the near correction is added to the lower segment of the
distance lens.
- Varifocal lenses where the power of the lens gradually changes from the distance
correction (in the upper part) to the near correction (in the lower part). This provides
sharper middle-distance vision but the lenses may be difficult to manage.
- People with particular needs, such as musicians, may also need glasses for middle
distance.

Q: Comment on procedure and risks of LASIK?

- In laser assisted in situ keratomileusis (LASIK), a hinged partial thickness corneal stromal
flap is first created with a rapidly moving automated blade.
- The flap is lifted and the laser applied onto the stromal bed. Unlike PRK, LASIK provides a
near instantaneous improvement in vision with minimal discomfort.
- Serious complications during flap creation occur rarely. Intraocular lenses can also be
placed in the eye but this carries all the risks of intraocular surgery and the possibility of
cataract formation.

Chapter4: The orbit

Q: What is exophthalmos, write some causes?

- Exophthalmos is protrusion of the eye caused by a space-occupying lesion.
- It can be measured with an exophthalmometer  difference of more than 3 mm between
the two eyes is significant.
- Causes:
1- intra-conal lesion (like optic nerve sheath meningioma)  the eye is displaced directly
forward.
2- extra-conal lesion (tumor of the lacrimal gland)  the eye is displaced to one side.
3- Vascular cause   transient proptosis induced by increasing the cephalic venous
pressure (by aValsalva manoeuvre), is a sign of orbital varices.

4- Vascular cause  the presence of pain may suggest infection (e.g. orbital cellulitis).
5- Endocrine cause unilateral or bilateral hyperthyroidism.
6- The speed of onset of proptosis may also give clues to the aetiology,,,ex:-  slow
onsetbenign tumor// rapid onset inflammatory disorders, malignant tumors and
carotid-cavernous sinus fistula.
7- The commonest cause of bilateral proptosis is dysthyroid disease (Dysthyroid disease
may be associated with the serious complications  of exposure keratopathy and optic nerve
compression).

Q: Write about orbital cellulitis?

- Introduction:
Orbital cellulitis is a serious condition which can cause blindness and  may spread to cause a
brain abscess.
The infection often arises from  an adjacent ethmoid sinus.
The commonest causative organism is Haemophilus influenzae.
- Presentation:
painful eye.
periorbital inflammation and swelling; mild proptosis
reduced eye movements
conjunctival injection
possible visual loss
systemic illness and pyrexia.
- Diagnosis & treatment :
An MRI or CT scan is helpful in diagnosis and in planning treatment .
The condition usually responds to intravenous broad spectrum antibiotics.
It may be necessary to drain an abscess or decompress the orbit particularly if the optic
nerve is compromised.
Optic nerve function must be closely watched, monitoring acuity, colour vision and testing
for a relative afferent pupillary defect.
Orbital decompression is usually performed with the help of an ENT specialist.

Q: Write about types and treatment of orbital tumors?

1- Benign tumors: still require complete excision to prevent malignant transformation.
2- lacrimal gland tumors: Malignant lacrimal gland tumors carry a poor prognosis
3- optic nerve gliomas: may  be  associated  with neurofibromatosis.
4- Meningiomas:
Meningiomas of the optic nerve are rare, and may also be difficult to excise, again they can
be observed and some may benefit from treatment with radiotherapy.
Meningiomas from the middle cranial fossa may spread through the optic canal into the
orbit.
5- Lymphomas: the treatment of lymphoma requires a full systemic investigation,
Widespread disease (chemotherapy), localized to the orbit (localized radiotherapy).
6- Rhabdomyosarcoma: it is the commonest orbital tumor in children, it is rapidly growing
tumor of striated muscle, chemotherapy is effective if the disease is localized to the orbit.

7- Metastasis from other systemic cancers: neuroblastomas in children, the breast, lung,
prostate or gastrointestinal tract in the adult.

Chapter5: Eyelids

Q: What are the causes, signs, symptoms, treatment of ptosis?

Causes:
1- Mechanical factors  Large lid lesions pulling down the lid - Lid oedema -Tethering of
the lid by conjunctival scarring - Structural abnormalities including a disinsertion of the
aponeurosis of the levator muscle, usually in elderly patients.
2- Neurological factors  Third nerve palsy - Horner's syndrome - Marcus Gunn jaw-
winking syndrome.
3- Myogenic factors  Myasthenia gravis - muscular dystrophy - Chronic external
ophthalmoplegia.
Symptoms:
Cosmetic effect - vision may be impaired - there are symptoms and signs associated with
the underlying cause (e.g. asymmetric pupils in Horner's syndrome, diplopia and reduced
eye  movements in a third nerve palsy).
Signs:
1- There is a reduction in size of the interpalpebral aperture.
2- The upper  lid margin, which usually overlaps the upper limbus by 1-2 mm, may be
partially covering the pupil.
3- The function of the levator muscle can be tested by measuring the maximum  travel of
the upper lid from upgaze  to downgaze (normally 15 -18 mm).
4- Pressure on the brow (frontalis muscle) during this test will prevent its contribution to lid
elevation.
5- If myasthenia is suspected the ptosis should be observed during repeated lid movement,
increasing  ptosis after  repeated  elevation  and  depression of the lid is suggestive of
myasthenia.
6- Other underlying signs, for example of Horner's syndrome or a third nerve palsy, may be
present.
Treatment:
1- It is important to exclude an underlying cause whose treatment could  resolve the
problem (e.g. myasthenia gravis).
2- Ptosis otherwise requires surgical correction.
3- In very young children this is usually deferred but may  be expedited if pupil cover
threatens to induce amblyopia.

Q: Write some notes about blepharitis?

Introduction:
Chronic eyelid inflammation, sometimes associated with chronic staphylococcal infection.
The condition causes squamous debris, inflammation of the lid margin, skin and  eyelash
follicles (anterior blepharitis).

The meibomian glands may be affected independently (meibomian gland disease or
posterior blepharitis).
Symptoms:
Tired, sore eyes, worse in the morning,crusting of the lid margin.
Signs:
- scaling of the lid margins.
- debris in the form of a rosette around the eyelash, the base of which  may also be
ulcerated, a sign of staphylococcal infection.
- A reduction in the number of eyelashes.
- obstruction and plugging of the meibomian ducts.
- cloudy meibomian secretions
- injection of the lid margin
- tear film abnormalities.
- Blepharitis is strongly associated with seborrhoeic dermatitis, atopic  eczema and acne
rosacea.
Treatment:
1- For anterior blepharitis lid  toilet with a cotton bud wetted with bicarbonate solution
or diluted baby  shampoo helps to remove squamous debris from the eye.
2- Topical steroids may improve an anterior blepharitis but frequent use is best  avoided.
3- Posterior blepharitis can be associated with a dry eye which requires treatment with
artificial tears.
4- Abnormal meibomian gland secretions can be expressed by lid massage after hot
bathing.
5- Meibomian gland function can be improved by oral tetracycline.
6- Staphylococcal lid disease may also require therapy with topical  antibiotics (fusidic acid
gel) and, occasionally, with systemic antibiotics.

Q: Numerate the benign lumps of the eyelid?

- Chalazion.
- Molluscum contagiosum.
- Cyst.
- Squamous cell papilloma.
- Xanthelasma.
- Keratocanthoma.
- Nevus (mole).

Q: Write short notes about Trichiasis?

- It is aberrant  eyelashes  are directed backwards towards the globe, The lashes rub
against the cornea and cause irritation and abrasion, may cuased by trachoma, it is distinct
from entropion, it may result from any  cicatricial process.
- Treatment:

  epilation of the offending lashes.
  Recurrence can be treated with cryotherapy or electrolysis.
  Any underlying abnormality of lid position needs surgical correction.

Chapter6: The lacrimal system

Q: Write short notes about keratoconjunctivitis sicca?

Causes:
- With dry mouth and other mucous membranes  primary Sjögren’s syndrome

( an auto-

immune exocrinopathy.
- With auto-immune connective tissue disorder (Rheumatoid arthritis)   secondary
Sjögren’s syndrome .
Symptoms:
burning, photophobia ,heaviness of the lids and ocular fatigue  .worse in the  evening

visual  acuity may be reduced by corneal damage.
Sings:
punctate staining )over  the exposed corneal and conjunctival surface  .

(

In severe cases tags of abnormal mucus may attach to the corneal surface

( filamentary

keratitis )causing pain due to tugging on these filaments during blinking
Treatment:
tear substitutes
shielded spectacles.
severe cases it may be necessary to occlude the punta with plugs, or more permanently
with surgery, to conserve the  tears.

Q: What are the causes of inadequate mucus production?

1-Destruction of the goblet cells as in dry eye
2-cicatricial conjunctival disorders e.g. erythema multiforme (Stevens–Johnson’s syndrome)
3-Chemical burns of the eye, particularly by alkalis
4-trachoma.
5-Vitamin A deficiency (xerophthalmia. Goblet cells are lost from  the conjunctiva and the
ocular surface becomes keratinized (xerosis).

Q: How to diagnose and treat adult with obstruction of nasolacrimal duct?

1- Diagnosis:
-History   watering eye وstickiness, eye is white, symptoms may be worse in the wind or
in  cold weather, there may be a history of previous trauma or infection.
- Slit lamp  stenosed punctum may be apparent on slit lamp examination .
- Syringing the naso-lacrimal system  Acquired obstruction.
- dacrocystogram  the exact location of the obstruction  can be confirmed by injecting a
radio-opaque dye into the naso-lacrimal  system (dacrocystogram( X-rays are then used to
follow the passage of the  dye through the system.
2- Treatment:
dacryocystorrhinostomy or  DCR  The operation can be performed through an incision on
the side of the nose but it may also be performed endoscopically through  the nasal
passages thus avoiding a scar on the  face.

Q: Write short notes about infection of nasolacrimal duct?

- Closed obstruction of the drainage system predisposes to infection of the sac
(dacryocystitis).

- Staphylococcus .
- Patients present with a painful swelling on the medial side of the orbit ,which is the
enlarged, infected sac .
- Treatment is with systemic antibiotics.
- A mucocoele results from a collection of mucus in an obstructed sac ,it is not infected.
- In either case a DCR may be necessary to prevent recurrence.

Chapter7: Conjunctiva, cornea, and sclera

Q: What are the signs and symptoms of corneal and conjunctival diseases in
general?

- Symptoms  pain, irritation, redness, discharge, visual loss, photophobia.
- Signs in conjunctiva  papillae, follicles, injection, subconjunctival hemorrhage.
- Signs in cornea  clouding, edema, keratic precipates, new blood vessels, punctate
epitjelial erosions.

Q: Write short notes about allergic conjunctivitis?

This may be divided into acute and chronic forms:
-  Acute (hay fever conjunctivitis). This is an acute IgE-mediated reaction to airborne
allergens (usually pollens). Symptoms and signs include: itchiness; conjunctival injection
and swelling (chemosis); lacrimation.
2- Vernal conjunctivitis (spring catarrh) is also mediated by IgE. It often affects male
children with a history of atopy. It may be present all year long.
Symptoms and signs include:
itchiness;
photophobia;
lacrimation;
papillary conjunctivitis on the upper tarsal plate (papillae may  coalesce to form giant
cobblestones; Fig. 7.4);
limbal follicles and white spots;
)  punctate lesions on the corneal epithelium;
an opaque, oval plaque which in severe disease replaces an upper  zone of the corneal
epithelium.
Treatment:
Initial therapy is with antihistamines and mast cell stabilizers (e.g.  sodium cromoglycate;
nedocromil; lodoxamide).
Topical steroids
Contact lens wearers may develop an allergic reaction to their lenses or to lens cleaning
materials leading to a giant papillary conjunctivitis (GPC)  with a mucoid discharge.

Q: Write short notes about herpes simplex keratitis?

Type 1 herpes simplex (HSV) is a common and important cause of  ocular disease. Type 2
which causes genital disease may occasionally cause  keratitis and infantile chorioretinitis.
Primary infection by HSV1 is usually acquired early in life by close contact such as kissing. It
is accompanied by:
fever; vesicular lid lesions; follicular conjunctivitis; pre-auricular lymphadenopathy;
most are asymptomatic.
The cornea may not be involved although punctate epithelial damage  may be seen.
Recurrent infection dendritic ulcers on the cornea. heal without a scar.
If the stroma is also involved oedema develops causing a loss of corneal      transparency.
Involvement of the stroma may lead to permanent scarring.
Uveitis and glaucoma may accompany the disease.
Disciform keratitis is an immunogenic reaction to herpes antigen in the stroma and
presents  as stromal clouding without ulceration, often associated with iritis.
Dendritic lesions are treated with topical antivirals which typically heal  within 2 weeks.
Topical steroids

Q: Write short notes about keratoconus?

It is Progressive coning of cornea due to thinning of inf. Paracentral stroma.
Usually bilateral but may be asymmetrical
Start in teens age (puberty), more in females.

Associations:

1. Vernal catarrh

2. Atopic dermatitis

3. Down syndrome

4. Turner syndrome
5. Marfan syndrome
6. Ehler Danlos Syndrome

Present: Progressive blurring of vision (irregular myopic astigmatism & corneal opacities).

O/E:
1- Thinning & forward bowing of inf. Paracentral cornea stroma (slit lamp ex.)
2- Brownish ring (Fleischer) around the base of cone due to hemosiderin deposit.
3- Distortion of the corneal light reflection (placido disc).
4- Altered ophthalmoscopic & retinoscopic light reflexes.
5- Munson’s sign )indentation of the lower lid by the conical cornea when patient looks
downward).
6- Acute hydrops=stromal oedema due to rupture descemet membrane.
Nowadays ,it is mostly diagnosed by corneal topography examination during the pre-
oprative assessment of refractive surgery

Treatment:
1-  Corneal Collagen Cross-linking, in early cases to arrest the disease
2- Glasses
3-  Contact lenses (Rigid)
4- Intra-stromal corneal rings
5- Penetrating keratoplasty or Lamellar keratoplasty..in advanced cases or corneal scarring

Q: Write short notes about corneal grafting?

Donor corneal tissue can be grafted into a host cornea to restore corneal  clarity or repair a
perforation. Donor corneae can be stored and are  banked so that corneal grafts can be
performed on routine operating lists.  The avascular host cornea provides an immune
privileged site for grafting,
with a high success rate. Tissue can be HLA-typed for grafting of vascularized corneae at
high risk of immune rejection although the value of this is still uncertain. The patient uses
steroid eye drops for some time after the  operation to prevent graft rejection.
Complications such as astigmatism  can be dealt with surgically or by suture adjustment.
GRAFT REJECTION
Any patient who has had a corneal graft and who complains of redness,  pain or visual loss
must be seen urgently by an eye specialist, as this may  indicate graft rejection. Examination
shows graft oedema, iritis and a line  of activated T-cells attacking the graft endothelium.
Intensive topical  steroid application in the early stages can restore graft clarity.

Q: Write short notes about scleritis?

more severe condition than episcleritis
may be associated  with the collagen-vascular diseases, most commonly rheumatoid
arthritis.  It is a cause of intense ocular pain. Both inflammatory areas and ischaemic  areas
of the sclera may occur. Characteristically the affected sclera is  swollen. The following may
complicate the condition:
scleral thinning (scleromalacia), sometimes with perforation;
keratitis;
uveitis;
cataract formation;
glaucoma.
Treatment may require high doses of systemic steroids or in severe cases cytotoxic therapy
and investigation to find any associated systemic disease.
Scleritis affecting the posterior part of the globe may cause choroidal  effusions or simulate
a tumour.

Chapter8: Cataract

Q: What are the causes of cataract?

1- Age related cataract the large majority of cataracts occur in older age as a result of the
cumulative exposure to environmental and other influences such as smoking, UV radiation
and elevated blood sugar levels.
2- Ocular conditions  Trauma, Uveitis, High myopia, Topical medication (particularly
steroid eye drops), Intraocular tumor
3- Systemic causes  Diabetes, Other metabolic disorders )galactosaemia, Fabry’s disease,
hypocalcaemia), Systemic drugs (particularly steroids, chlorpromazine), Infection
(congenital rubella), Myotonic dystrophy, Atopic dermatitis, Systemic syndromes )Down’s,
Lowe’s( Congenital, including inherited, cataract X-radiation

Q: What are the complications of cataract surgery?

1.  Vitreous loss.
2.  Iris prolapse.
3.  Endophthalmitis. A serious but rare infective complication of cataract extraction (less

than 0.3%). Patients present with:



A painful red eye;



Reduced visual acuity, usually within a few days of surgery;



A collection of white cells in the anterior chamber (hypopyon). The patient
requires urgent ophthalmic assessment, sampling of aqueous and vitreous for
microbiological analysis and treatment with intravitreal, topical and systemic
antibiotics.

4.  Postoperative astigmatism.
5.  Cystoid macular oedema.
6.  Retinal detachment.
7.  Opacification of the posterior capsule.
8.  If the fine nylon sutures are not removed after surgery they may break in the following

months or years causing irritation or infection. Symptoms are cured by removal.

Q: Write short notes about ectopia lentis?

Weakness of the zonule causes lens displacement. The lens takes up a more rounded form
and the eye becomes more myopic. This may be seen in:



Trauma.



Inborn errors of metabolism (e.g. homocystinuria, a recessive disorder with mental
defect and skeletal features. The lens is usually displaced downwards).



Certain syndromes )e.g. Marfan’s syndrome, a dominant disorder with skeletal and
cardiac abnormalities and a risk of dissecting aortic aneurysm. The lens is usually
displaced upwards). There is a defect in the zonular protein due to a mutation in the
fibrillin gene.

The irregular myopia can be corrected optically although sometimes an aphakic correction
may be required if the lens is substantially displaced from the visual axis. Surgical removal
may be indicated, particularly if the displaced lens has caused a secondary glaucoma but
surgery may result in further complications.

Questions from previous exams:

Q: Write short notes about complication of trachoma?

Trachoma
The commonest infective cause of blindness in the world.The housefly acts as a vector and
the  disease is encouraged by poor hygiene and overcrowding in a dry, hot  climate.
subconjunctival fibrosis caused  by frequent re-infections associated with the unhygienic
conditions.
Blindness may occur due to corneal scarring from recurrent keratitis and  trichiasis.
treated with oral or topical tetracycline or erythromycin. Azithromycin, an alternative,
requires only one application. Entropion and  trichiasis require surgical correction.

Q: Write short notes about evaluation of ptosis?

(in page 5 above)

Q: Write short notes about risks factors of bacterial keratitis?



keratoconjunctivitis sicca (dry eye);



a breach in the corneal epithelium (e.g. following trauma);



contact lens wear;



prolonged use of topical steroids.

Q: Write short notes about complications of cataract surgery?

(in page 11 above)

Q: Write short notes about clinical presentation in cataract?

SYMPTOMS
An opacity in the lens of the eye:



Causes a painless loss of vision;



Causes glare;



May change refractive error.

In infants, cataract may cause amblyopia (a failure of normal visual development) because
the retina is deprived of a formed image. Infants with suspected cataract or a family history
of congenital cataracts should be seen as a matter of urgency by an ophthalmologist.

SIGNS
Visual acuity is reduced. In some patients the acuity measured in a dark room may seem
satisfactory, whereas if the same test is carried out in bright light or sunlight the acuity will
be seen to fall, as a result of glare and loss of contrast.

The cataract appears black against the red reflex when the eye is examined with a direct
ophthalmoscope (see pp. 29–30). Slit lamp examination allows the cataract to be examined
in detail and the exact site of the opacity can be identified.

Q: Discus the treatment of congenital dacryocystitis?

The distal end of the naso-lacrimal duct may remain imperforate ,causing a watering
eye .

mucocoele

dacrocystitis .

Diagnostically the discharge may be expressed from the puncta by pressure over the
lacrimal sac .The conjunctiva ,however ,is not inflamed .

Most obstructions resolve spontaneously in the first year of life

probing via the punctum through the naso-lacrimal duct to perforate the occluding
membrane (probing). A general anaesthetic is required.

Q: Write short notes about Ophthalmia neonatorum?

any conjunctivitis in the first 28 days of neonatal life, Swabs for culture are mandatory. It is
also important that the cornea is examined to exclude any ulceration.

The commonest organisms are:

Bacterial conjunctivitis (usually Gram positive).

Neisseria gonorrhoea. In severe cases this can cause corneal perforation. Penicillin given
topically and systemically is used to treat the local and systemic disease respectively.

Herpes simplex, which can cause corneal scarring.Topical antivirals are used to treat the
condition.

Chlamydia. This may be responsible for a chronic conjunctivitis and  cause sight-threatening
corneal scarring.Topical tetracycline ointment and  systemic erythromycin is used is used to
treat the local and systemic  disease respectively.

Q: Write short notes about scleritis?

(

n page 2 above)

Q: Write short notes about drainage of aqueous humour?

(in page 10 above)

Q: Outline the management of keratoconus?

(in page 9 above)