2. CORNEA
MEGALOCORNEA
• Bilateral condition
• Corneal diameter is more than 14 mm.
• The cornea is usually clear with normal thickness and vision.
• Often associated with marfan’s syndrome.
• Differential diagnosis can be differentiated from buphthalmos and
keratoglobus
I. Buphthalmos—In this condition 10P is raised and eyeball is enlarged
as a whole. Enlarged cornea is associated with Descemet’s membrane
tears.
ii. Keratoglobus—There is congenital bilateral hemispherical
protrusion of the whole cornea.
3.
4. Cont.
KERATOGLOBUS
• There is thinning and excessive protrusion of
cornea which seems enlarged but its diameter
is usually normal.
5. Cont.
MICROCORNEA
• The corneal diameter is less
than 10 mm with decreased
radius of curvature.
• Hypermetropia and narrow
angle glaucoma may be found
in later years.
• The condition may occur as an
isolated anomaly or in
association with
microphthalmos.
6. Cont.
CORNEA PLANA
• It is a rare anomaly in which cornea is
comparatively flat since birth.
• It may be associated with microcornea.
7. Cont.
POSTERIOR
EMBRYOTOXON
• There is an unusual
prominence of
Schwalbe’s line which is
peripheral termination
of Descemet’s
membrane.
• It appears as a ring
opacity in deeper layer
of cornea.
8.
9. UVEAL TRACT
HETEROCHROMIA IRIDUM
– One iris may have a different colour from the other.
HETEROCHROMIA IRIDIS
– Parts of one iris may have different colour.
POLYCORIA
– There are more than one pupil.
CORECTOPIA
– The pupil is not central but displaced to the nasal side
usually.
ANIRIDIA
– It is a bilateral condition.
– The iris is absent except for a narrow rim at the ciliary
border. It often leads to secondary glaucoma.
10.
11. Cont,
PERSISTENT PUPILLARY MEMBRANE
• Commonly seen in babies.
• There is persistence of part of anterior vascular
sheath of the lens which normally disappears before
birth.
• Clinical Features
• Fine threads stretch across the pupil.
• It may be attached to lens capsule.
• Pigments are seen on the lens surface as fine brown dots.
• It does not interfere with vision usually.
12. DIFFERENTIAL DIAGNOSIS
• It is differentiated from the posterior
synechiae
i. In persistent pupillary
membrane, fine threads are attached to
the anterior surface of iris just outside
the pupillary margin.
ii. There are no keratic
precipitates or other signs of iritis.
13. Cont.
COLOBOMATA
• Deficient closure of the embryonic cleft
resulting in abnormal shape of the iris.
Clinical features
1. Iris
i. Typical—pear-shaped coloboma is seen in the
lower part and slightly inwards.
ii. Atypical—defect in iris is seen in any other
direction.
14. Cont.
2. Choroid and retina
– Fundus examination shows oval
or comet-shaped defect with
rounded apex towards the disc.
– The disc may be included in the
defect.
– Few vessels are seen over the
surface and edge.
– The central vision is defective.
– Field of vision—scotoma is
present corresponding to the
defect.
15. Cont.
ALBINISM
• It is a hereditary condition of defective development
of pigment throughout the body.
• Type
– 1. Ocular
– 2. Oculocutaneous
– 3. Cutaneous.
• Symptoms
1. There is defective vision.
2. Photophobia and dazzling may be present.
3. Nystagmus is usually associated if macula is involved.
4. Strabismus may be present.
16.
17. Cont.
• Signs
1. Iris is pink in colour
2. Fundus examination—Retinal and
choroidal vessels are seen with great
clarity with glistening white sclera behind
them.
3. Partial albinism is more common. The
iris is blue and the pigments are absent
from choroid and retina. The macula may
be pigmented and may therefore look
normal.
• Treatment
– Use of tinted glasses as a protection
from glare is recommended.
18. Cont.
CYSTS
1. Serous cyst—It is due to closure of the iris
crypts.
2. Cyst of posterior epithelium—It must be
differentiated from iris bombe.
3. Implantation cyst—It occurs commonly after
perforating wounds or operations.
19.
20. LENS- CONGENITAL CATARACT
CONGENITAL (DEVELOPMENTAL) CATARACT
• Present at birth or it may occur in early childhood.
• It has a tendency to affect a particular zone (usually bilateral)
• It is usually stationary but may be progressive.
ETIOLOGY
1. Heredity- genetic mutation, usually autosomal dominant.
2. Maternal causes
i. Maternal malnutrition, e.g. as in zonular cataract.
ii. Maternal infection by virus, e.g. rubella in the first trimester.
3. Foetal causes
i. Deficient oxygenation due to severe placental haemorrhage
ii. Metabolic disorders of the foetus or infant like galactosaemia, galactokinase
deficiency
iii. Chromosomal abnormalities, e.g. as in Down syndrome (trisomy 21)
4. Idiopathic—Unilateral cataracts are usually sporadic and of unknown
etiology.
21.
22. Cont.
• Symptoms
1. If the opacity is large and central in position,(marked
visual impairment.)
2. White reflex
3. Abnormal movements of the eye due to squint or
nystagmus may be present.
• Signs
1. White reflex is present in the pupillary area.
2. Plane mirror examination—There is black opacity against
a red background.
3. Ophthalmoscopic examination—There is black opacity
against a red background.
23.
24. Cont.
CLINICAL TYPES
1. Punctate or blue-dot
cataract
– It is the most common
variety.
– Multiple small, opaque,
scattered dots are seen.
– It does not interfere with
vision usually.
25. Cont.
2. Zonular cataract
• it is bilateral with strong dominant hereditary
tendency.
• Malnutrition and lack of vitamin d may cause
• It is the most common congenital cataract.
• An area around embryonic nucleus becomes
opacified and two rings of opacity are seen.
• The opacity is sharply demarked and the area of the
lens within and around the opacity is clear.
• Linear opacities or riders may run towards the
equator
26.
27. Cont.
3. Coronary cataract
• It commonly occurs at
puberty.
• It is situated in the deep
layers of cortex and
superficial layers of nucleus.
• There are multiple club-
shaped opacities near the
periphery of the lens
usually hidden by the iris.
28. Cont.
4. Anterior capsular cataract
• It is due to the delayed
formation of the anterior
chamber.
• It may occur following
perforation of a corneal ulcer in
ophthalmia neonatorum cases.
• It may project forwards into the
anterior chamber like a pyramid
(anterior pyramidal cataract).
• The underlying cortex may
become opaque (anterior
cortical cataract) occasionally.
29. Cont.
5. Posterior capsular
cataract
• It is often due to
persistence of
posterior part of
vascular sheath.
• Persistence of hyaloid
artery may eventually
result in total cataract.
30. INVESTIGATION
• Density and morphology of cataract is noted based on childs
vision and visibility of fundus on ophthalmoscopy.
• Refraction by retinoscopy under atropine is done in partial
cataract.
• Associated ocular pathology
• Intraocular pressure is noted.
• B-scan ultrasonography is useful in assessing posterior segment
of the eye in total cataract to rule out associated retinal
detachment or retinoblastoma.
• A-scan ultrasonography is done to record and compare the axial
lenghts of two eyes.
• Serum biochemistry
• Urine analysis
• Serological tests for estimating the titres of antibody for
infections.
31. TREATMENT
1. No treatment—No treatment is required if the vision is
good.
2. Mydriasis with atropine—It is advocated atleast until
puberty if the cataract is small, central and the vision is
good. Once a week
3. Optical iridectomy—It may be done if the opacity is
small, central and stationary.
4. Lens aspiration—Aspiration of lens matter can be done
as the lens material is soft in children. This is followed by
IOL implantation.
5. Lensectomy—In this operation, the lens including
anterior and posterior capsule along with anterior
vitreous are removed.
32. RETINA
COLOBOMA OF RETINA AND CHOROID
• Defective closure of the embryonic cleft.
• They are present in the lower part of the eye
(typical) and may be associated with
coloboma of the iris.
33. OPTIC NERVE
COLOBOMA
• Bilateral in more than half the cases.
• Two forms:
i. Inferior crescent
• this is a common form occurring due to
incomplete closure of the embryonic fissure.
• It occurs in hypermetropic and astigmatic eyes.
• It may be ectatic.
ii. Coloboma of the disc—there is a greater failure of
the embryonic fissure to close. The apparent large disc
is really the sclera. The vision is defective usually.
34.
35. Cont.
MEDULLATED (OPAQUE) NERVE FIBRES
• Normally the myelin sheaths of optic
nerve stop at the lamina cribrosa.
• Occasionally patches of nerve fibres
regain these sheaths after they have
passed through the lamina cribrosa.
• They appear as white glistening patches
with radially striated edges.
• They are continuous with the optic disc.
37. LACRIMAL
CONGENITAL ANOMALIES OF THE PUNCTA AND
CANALICULI
• Puncta may be absent or constricted.
• There may be two puncta in a lid, both opening
into the same canaliculus.
• Groove is found instead of a canaliculus.
• The canaliculus may be occluded
Treatment
1. Punctum dilator is inserted in the punctum.
2. An opening is made and canaliculus knife is
introduced in the punctum
38.
39. Cont.
CONGENITAL DACRYOCYSTITIS (DACRYOCYSTITIS IN THE NEWBORN)
• Present as an acute or chronic process.
• Failure in canalization of the nasolacrimal duct, the lumen being
blocked by epithelial debris.
• Bilateral condition.
Symptom
1. There is epiphora or continuous watering of the eyes usually evident
in 2nd week of life. Normally, the tears are secreted after 3-4 weeks
after birth.
2. There may be purulent discharge or conjunctivitis in infected cases.
Signs
1. Stricky mucopurulent discharge and persistent epiphora are two
important signs.
2. There is regurgitation of mucopurulent discharge on pressure over the
sac area.
40.
41. Treatment
CONSERVATIVE TREATMENT IS INDICATED IN EARLY
CASES.
i. Massage over the lacrimal sac area and clean
the discharge several times a day.
SURGICAL TREATMENT
To recanalise the nasolacrimal duct.
i. Probing of the nasolacrimal duct.
ii. Intubation with silicone
iii. Balloon dilatation of the duct may be tried.
iv. Dacryocystorhinostomy (DCR) operation.