5. In general, the earlier the onset, the more amblyogenic the
cataract will be.
Lens opacities that are visually significant before 2–3 months
of age are the most likely to be detrimental to vision.
7. Morphology
○ Blue dot opacities are common and innocuous.
○ Nuclear opacities are confined to the embryonic or fetal nucleus.
○ Lamellar opacities affect a particular lamella of the lens both anteriorly and
posteriorly and may be associated with radial extensions.
Lamellar opacities may be autosomal dominant or occur in isolation as well as in
association with metabolic disorders and intrauterine infections.
○ Coronary (supranuclear) cataract lies in the deep cortex, surrounding the
nucleus like a crown. It is usually sporadic but occasionally hereditary.
8. Central ‘oil droplet’ opacities (Fig. 9.25D) are characteristic of galactosaemia.
○ Posterior polar cataract (Fig. 9.25E) may be associated with posterior
lenticonus or fetal vascular remnants including a Mittendorf dot. This form of
opacity is often closely integrated with the lens capsule and/or a pre-existing
defect, with a very high risk of dehiscence during surgery.
○ Sutural, in which the opacity follows the anterior or posterior Y suture may
be seen in female Nance–Horan carriers.
○ Anterior polar cataract may be flat or project into the AC. Occasional
associations include persistent pupillary membrane, aniridia, Peters anomaly
and anterior lenticonus.
10. Lamellar opacities affect a particular lamella of the lens both anteriorly and posteriorly and may be associated with
radial extensions (‘riders’ ). Lamellar opacities may be autosomal dominant or occur in isolation as well as in
association with metabolic disorders and intrauterine infections.
13. Fabry disease is an X-linked lysosomal storage disorder caused by a deficiency of the enzyme
alpha-galactosidase A that leads to abnormal tissue accumulation of a glycolipid.
All males with the gene develop the disease, and some heterozygous females.
Systemic features include periodic burning pain in the extremities (acroparaesthesia) and GI
tract, angiokeratomas cardiomyopathy and renal disease.
Ocular manifestations
white to golden-brown corneal opacities in a vortex pattern (75%) that may be the first feature
of the disease facilitating early intervention;
wedge- or spoke-shaped posterior cataract (Fabry cataract)
conjunctival vascular tortuosity (corkscrew vessels) and aneurysm formation
retinal vascular tortuosity.
FABRY’S DISEASE
18. LOWE’S SYNDROME
Lowe (oculocerebrorenal) syndrome is an X-linked
recessive disorder
Gene: OCRL1
inborn error of amino acid metabolism
Neuromuscular and renal manifestations are seen
Cataract is universal
Congenital glaucoma is present in about half of
patients.
21. Galactosaemia is an autosomal recessive (AR) condition
characterized by impairment of galactose utilization caused
by absence of the enzyme galactose-1-phosphate uridyl
transferase (GPUT).
Unless galactose (milk and milk products) is withheld from
the diet, severe systemic complications culminate in early
death.
‘Oil droplet’ lens opacity develops within the first few days or
weeks of life in a large percentage of patients.
GALACTOSSEMIA
23. Mannosidosis is an AR disorder with deficiency of α-mannosidase.
Infantile and juvenile-adult forms are seen
Progressive mental deterioration, musculoskeletal and other
abnormalities.
Punctate lens opacities arranged in a spoke-like pattern in the
posterior lens cortex are frequent
MANNOSIDOSIS
25. Ocular assessment
Determination in the neonate of the visual significance of lens opacity is
based principally on the appearance of the red reflex and the quality of the
fundus view.
• A very dense cataract occluding the pupil; the decision to operate is
straightforward.
• A less dense but still visually significant cataract (e.g. central or posterior
opacities over 3 mm in diameter) will permit visualization of the retinal
vasculature with the indirect but not with the direct ophthalmoscope.
• A visually insignificant opacity will allow clear visualization of the retinal
vasculature with both the indirect and direct ophthalmoscope.
• Other indicators of severe visual impairment include absence of central
fixation, nystagmus and strabismus.
26. • Preoperative evaluation
• History taking is an integral part in the evaluation of an infant with
congenital cataract.
• The history should include
1. Antenatal history of maternal drug intake and fever- with rash,
family history of congenital cataract.
2. Birth history should be specifically looked for as bilateral congenital
cataract is more common in preterm, low birthweight, small for
gestational age children.
27. 3.Developmental mile stones should be carefully assessed.
4. History of visual interaction of the child with the family members should also
be inquired as it helps in determining the severity of visual dysfunction.
5. History of the onset of the opacities, progression and laterality is also
important. Unilateral cataracts are isolated but are usually associated with
other ocular abnormalities like persistent fetal vasculature, lenticonus,
lentiglobus
29. • Clinical Examination
• Detailed ocular examination of the child can be done either in an outpatient
setting if the child is cooperative or under general anesthesia.
• In infants, fixation behavior, fixation preference and resistance to occlusion
gives us a clue to the visual acuity.
• Dense central opacities larger than 3 mm in diameter usually need surgical
removal
30. • Examination of both the eyes has to be done to determine whether the cataract
is unilateral or bilateral.
• Unilateral cataract, even if mild can cause irreversible deep amblyopia if not
treated.
• Often the first symptom is a white or partially white reflex noted by the
parents.
• Strabismus and nystagmus should be specifically looked for in these children
and sometimes these may be the presenting signs.
31. • Strabismus is usually seen in children with unilateral cataracts and develops
when an irreparable visual loss has already occurred.
• The presence of manifest nystagmus at age of 2–3 months or elder generally
indicates a very poor prognosis.
• The presence of either strabismus or nystagmus indicates that cataract is
visually significant.
32. In cases where the media opacity precludes examination of the fundus, a B
scan ultrasonography has to be performed to rule out other posterior
segment pathologies that mimic congenital cataract.
These conditions include retinoblastoma, persistent hyperplastic primary
vitreous, coats disease, ROP with retrolental fibroplasia, orgainzed vitreous
hemorrhage, congenital falciform fold, ocular toxocariasis and retinal
hamartomas.
Performing cataract surgery in these conditions is disastrous and can lead
one into medicolegal problems.
Oil droplet cataract seen in retroillumination
Increased osmotic pressure
CORNEAL CLOUDING CAN ALSO BE SEEN BUT IS LESS COMMON
Determination in the neonate of the visual significance of lens opacity is based principally on the appearance of the red reflex and the quality of the fundus view.