Introduction

• Opacity in lens

• Can be: Visually significant or not Stable or Progressive Congenital or Acquired Unilateral or Bilateral Partial or Complete

• Congenital: incidence 6/10 000 10% of childhood blindness

Classification : Acquired cataracts

• Systemic diseases : Diabetes mellitus : Myotonic dystrophy : Atopic dermatitis : Neurofibromatosis 2

• Ocular diseases : Chronic anterior uveitis : High myopia : Fundus dystrophies eg Retinitis pigmentosa

• Drugs : Corticosteroids : Chlorpromazine

• Trauma : Blunt : Sharp

Congenital cataracts: Bilateral• Genetic Mutation : Autosomal Dominant• Metabolic : Galactosaemia : Lowe : Hypoparathyroidism : Fabry

• Infective : TORCH organisms

• Chromosomal : Trisomy 21 (Down) : Trisomy 18 (Edward) : Trisomy 13 (Patau)

• Skeletal : Hallerman-Streiff : Nance-Horan• Ocular anomalies : Aniridia : Anterior segment dysgenesis syndrome• Idiopathic : in 50%

Congenital Cataracts• Responsible for nearly 10% of all visual loss in

children worldwide• Approximately 0.03% of newborns have some form

of congenital cataract • Most are not associated with additional

developmental problems • Around one fifth of these patients have a family

history of congenital cataract but in up to half of all cases there is no family history

Congenital cataract surgery

Cataract surgery in children, although complex and time consuming , can have excellent results. 1) Unilateral or bilateral 2) Cause : usually no cause is found

Cataract Types1)Polar Cataract2)Lamellar Cataract3)Sutural Cataract4)Coronary Cataract5)Cerulean Cataract6)Nuclear Cataract7)Capsular Cataract8)Membranous Cataract

1)Polar Cataract

2)Lamellar Cataract

3)Sutural Cataract

3)Sutural Cataract

4)Coronary Cataract

5)Cerulean Cataract(Blue Color)

5)Cerulean Cataract(Blue Color)

• Cerulean cataracts are opaque areas that develop in the lens of the eye that often have a bluish or whitish color. They may be present at birth or develop in very early childhood, but may not be diagnosed until adulthood.[1] They are usually bilateral and progressive.[2] Infants can be asymptomatic, but may also be visually impaired from birth and develop nystagmus and amblyopia.[2] In adulthood, the cataracts may progress, making lens removal necessary.[1] Cerulean cataracts may be caused by mutations in several genes, including the CRYBB2, CRYGD, and

MAF genes, and are inherited in an autosomal dominant manner. No treatment is known to prevent cerulean cataracts, but frequent evaluations and cataract surgery are typically required to prevent amblyopia as the opacities progress.

6)Nuclear Cataract

6)Nuclear Cataract

7)Capsular Cataract

8)Membranous cataract

Unilateral cataract• Unilateral cataracts are more

likely to cause visual loss because of the competition between the two eyes

Congenital cataracts: Unilateral

• Sporadic, no family history

• Ocular anomalies : Persistent fetal vasculature(PHPV)

• Cause identified in only 10%

Etiology There is no benefit in doing a large number of tests and

investigations on all children with cataract.It is better to take a careful history. a) Family history b) Any illnesses or drugs used during the pregnancy c) Pediatric consultation d) Intra – uterine infection ( rubella , cytomeygalovirus , syphilis)e) Hereditary systemic disorders

Downs syndrome Turners syndrome , Stickler syndrome

Etiology of Pediatric Cataracts

• Hereditary– Autosomal dominant form most common

• Genetic and Metabolic Diseases– Down syndrome– Marfan’s syndrome– Myotonic Dystrophy

• Maternal Infections– Rubella, Syphilis, Toxoplasmosis, Varicella

Rubella Virus

Rubella VirusRubella virus is the pathogenic agent of the disease Rubella, and is the cause of congenital rubella syndrome when infection occurs during the first weeks of pregnancy. Humans are the only known host of this virus.Rubella virus is the only member of the genus of Rubivirus and belongs to the family of Togaviridae, whose members commonly have a genome of single-stranded RNA of positive polarity which is enclosed by an icosahedral capsid.The molecular basis for the causation of congenital rubella syndrome are not yet completely clear, but in vitro studies with cell lines showed that Rubella virus has an apoptotic effect on certain cell types. There is evidence for a p53-dependent mechanism.

Rubella Virus

Rubella

cytomegalovirus

cytomegalovirus

Syphilis BacteriaTreponema pallidum is a Gram-negative spirochaete bacterium with subspecies that cause treponemal diseases such as syphilis, bejel, pinta and yaws. The treponemes have a cytoplasmic and outer membrane. This bacterium can be detected with special stains, such as the Dieterle stain.

Syphilis

Downs syndrome

Stickler syndromeStickler syndrome (hereditary progressive arthro-ophthalmopathy) is a group of genetic disorders affecting connective tissue, specifically collagen. [1] Stickler syndrome is a subtype of collagenopathy, types II and XI. Stickler syndrome is characterized by distinctive facial abnormalities, ocular problems, hearing loss, and joint problems. It was first studied and characterized by Gunnar B. Stickler in 1965.

Turner syndrome or Ullrich–Turner syndrome (also known as "Gonadal dysgenesis"[1]:550), 45,X, encompasses several conditions in human females, of which monosomy X (absence of an entire sex chromosome, the Barr body) is most common. It is a chromosomal abnormality in which all or part of one of the sex chromosomes is absent (unaffected humans have 46 chromosomes, of which two are sex chromosomes). Normal females have two X chromosomes, but in Turner syndrome, one of those sex chromosomes is missing or has other abnormalities.

• Common symptoms of Turner syndrome include:• Short stature• Lymphedema (swelling) of the hands and feet• Broad chest (shield chest) and widely spaced nipples• Low hairline• Low-set ears• Reproductive sterility• Rudimentary ovaries gonadal streak (underdeveloped

gonadal structures that later become fibrosed)• Amenorrhoea, or the absence of a menstrual period• Increased weight, obesity• Shield shaped thorax of heart• Shortened metacarpal IV• Small fingernails

• Characteristic facial features• Webbed neck from cystic hygroma in infancy• Coarctation of the aorta• Bicuspid aortic valve• Poor breast development• Horseshoe kidney• Visual impairments sclera, cornea, glaucoma, etc.• Ear infections and hearing loss• High waist-to-hip ratio (the hips are not much bigger than the waist)• Attention Deficit/Hyperactivity Disorder or ADHD (problems with

concentration, memory, attention with hyperactivity seen mostly in childhood and adolescence)

• Nonverbal Learning Disability (problems with math, social skills and spatial relations)

• Other features may include a small lower jaw (micrognathia), cubitus valgus,[8] soft upturned nails, palmar crease, and drooping eyelids. Less common are pigmented moles, hearing loss, and a high-arch palate (narrow maxilla). Turner syndrome manifests itself differently in each female affected by the condition, therefore, no two individuals will share the same features.

When to operate 1) If a child is behaving and developing

normally, do not operate , but keep under review.

2) Do not be misled by the red reflex as children may see remarkably well despite a copsular cataract through which no red reflex is visible

Loss of accommodation by surgery

3) Removing a cataract in a child removes their ability to accommodate.

The visually significant cataract

• In central visual axis, bigger than 3mm• Posterior cataract• No clear zones in between• Retinal details not visible with direct

ophthalmoscope• Nystagmus or strabismus present• Poor central fixation after 8 weeks

Treatment

• Surgery: Cataract extraction and intraocular lens implantation for visually significant cataract

• By 6 weeks of age

• Bilateral cases: 1 week apart

• Non visually significant cases : careful observation, possible pupillary dilation

Surgery 1) Cataract surgery in children is very different

to a cataract surgery in adults. 2) Children do not have a hard lens nucleus so it

can be removed by aspiration alone. 3) Anterior vitrectomy is necessary after

complete lens aspiration.4) An intact rim capsule is necessary.

Anterior vitrectomy is mandatory

Capsular rim

IoL insertion It is possible to insert an ioL at the time of

surgery or later as secondary procedure.Anterior capsule of a child is much more elastic

than an adult lens. So capsulorhexis is more difficult.

Post capsule If the capsule is left intact , it will opacify.

Lensectomy

It is belter to do lensectomy under 5 years of age and ECCE on older children for less risk of amblyopia.

So vision lost from capsule opacity can be regained.

How to prevent amblyopia In infants it is essential to correct aphakia as

soon as possible after surgery.1) One option is to implant an IoL when the

cataract is removed.2) Second option is contact lens .3) Third option is wearing glasses .

Problems with IoLAt birth the human lens is more spherical than in

adults. It has a power of about 30 D, which compensate for the shorter axial length of a baby's eye.

This decreases to about 20 – 22 D by the age of five. So an Iol which gives normal vision to an infant will lead to significant myopia when he or she is older.

IoL correct power ?Since corneal power of the cornea and axial

length of the globe, changes are most rapid during the first few years of life and this makes it almost impossible to predict the correct power of lens for IoL in any infant.

IoL Implantation

IoL implantation has become quite routine for older children, but it is still very controversial in younger children, particularly those under two years old.

Post operative care

In children the surgery is only the beginning of a prolonged course of treatment for prevention of amblyopia.

Refraction

2) Contact lens the first priority is to correct the aphakia and this should be done as early as possible.In rich countries contact lenses are widely used. They require meticulous hygiene.

3) Spectacles or an IoL.Even if an IoL is used there will be some residual refractive error and spectacles is necessary.

Complications of cat surgery 1) Amblyopia2) Posterior capsule opacification3) Glaucoma 4) Retinal detachment

Amblyopia 1) Most children with congenital cataract will be

amblyopic 2) removing the cataract and correcting the aphakia

can improve it's Nystagmus and amblyopia .3) Occlusion treatment of the preferred eye is very

essential. 4) The risk of amblyopia is greatest during the first

year of life and declines rapidly after the age of five.

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