CONGENITAL CATARACT

Roll No.: 131, 33

CONGENITAL CATARACT

ScenarioA 2 weeks old neonate was brought to eye OPD by his parents with the complaint of bilaterally white pupil.a. What is your differential diagnosis?b. Classify congenital cataract.c. What are the different causes of congenital cataract?d. How will you manage him?DefinitionCongenital opacity of the crystalline lens. Cloudiness in the lens of the eye that is present at, or develops shortly after birth.

Differential DiagnosisCongenital CataractRetinoblastomaColoboma of ChoroidCoats DiseaseRetrolental FibroplasiaNorries DiseasePersistant Hyperplastic Primary Vitreous

Exudative Retinitis

4Anatomy of the Lens

Types of CataractAnterior polar cataracts(Pyramidal)Lamellar (Zonular) Cataracts Most CommonPosterior polar cataractsNuclear cataractsCerulean cataracts (Blue Dot )Coronary Cataract Posterior Subcapsular CataractTotal/ Complete Cataract

Anterior polar cataractsare well defined, located in the front part of the eye's lens and thought to be commonly associated with inherited traits. These types of cataracts often are considered too small to require surgical intervention.Posterior polar cataractsalso are well defined, but appear in the back portion of the eye's lens.Nuclear cataractsappear in the central part of the lens and are a very common form of congenital cataracts.Cerulean cataractsusually are found in both eyes of infants and are distinguished by small, bluish dots in the lensTypically, this type of cataract does not cause vision problems. Cerulean cataracts appear to be associated with inherited tendencies.

7Posterior Polar

Anterior Polar

Cerulean / Blue-Dot Cataract

EtiologyBILATERALIdiopathic (60%)Hereditary (30%) Trisomy e.g. Downs, Edwards Intrauterine Infections - TORCHAssociated with ocular disordersTumorMetabolic Disorders Hypoglycemia, Hypocalcemia, Galactosemia Muscular Disorders -Myotonic DystophyMaternal drug ingestion.Malnutrition.Bilateral cataracts are often inherited and associated with other diseases. They require a full metabolic, infectious, systemic, and genetic workup. The common causes are hypoglycemia, trisomy (eg, Down, Edward, and Patau syndromes), myotonic dystrophy, infectious diseases (eg, toxoplasmosis, rubella, cytomegalovirus, and herpes simplex [TORCH]), and prematurity.16 UNILATERAL Idiopathic (80%) Intrauterine infection - Rubella Ocular abnormalities (10%) Lenticonus, Anterior Segment Dysgenesis Trauma (9%)EpidemiologyIncidence is about 1 in 2000, and approximately one-third of congenital cataractsare familial, one-third are associated with asyndrome, and one-third are isolated.Unilateral cataracts are usually isolated sporadic incidents. They can be associated with ocular abnormalities (eg, posterior lenticonus, persistent hyperplastic primary vitreous, anterior segment dysgenesis, posterior pole tumors), trauma, or intrauterine infection, particularly rubella.17DiagnosisHistory:DurationFamily history of congenital cataractsVisual status: Ambulation in familiar & unfamiliar surroundingsBehavioural pattern & school performance.

Birth history:History & Degree of consanguinityHistory of maternal infection during 1st trimesterGestational age & birth weightBirth traumaSupplemental O2 therapy in perinatal period.Developmental milestoneDiagnosisOcular Examination: Measurement of visual acuityPupil examinationExternal eye examination including lids and lashesMeasurement of intraocular pressureSlit lamp examination: associated congenital anomalies of iris & lens -type of cataract - iridodenesis/ phacodonesis.Dilated examination of the cataract and fundus.Biometry if the child is old enough to cooperate. If not this may need to bedone under anaesthesia.Management1.Medical CareMedical therapy is directed at the prevention of amblyopia.2. Surgical CareAspiration of the Lens matter is the treatment goal.Cataract surgery is the treatment of choice and should be performed when patients are younger than 17 weeks.Extracapsular cataract extraction with primary posterior capsulectomy and anterior vitrectomy is the procedure of choice (via limbal or pars plana approach).The resulting Aphakic Eye can be then managed via 3 options.

Contact Lens- If no IOL is implanted, contact lenses are given as early as possible to prevent stimulus deprivation amblyopia. Frequent retinoscopy should be performed to decide the power of CL and an overcorrection of +2 to +3D is mandatory. Silicon lenses or soft hydrogels are well tolerated.

Spectacles- In some children with bilateral aphakia spectacles are better tolerated than contact lenses. In addition a secondary strabismus may be manipulated by prismatic effect of spectacles. Bifocal glasses should be prescribed when the child is about to start school.

Intra-Occular-Lens (IOL)Preffered optionTraditional IOLs are monofocal, meaning they offer vision at one distance only.NewMultifocalandaccommodating IOLs suchs as Crysta Lens offer the possibility of seeing well at more than one distance.

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