Cataracts are usually thought of as a problem related to old age, but in reality, even infants and children can suffer from them. The paediatric cataract, whether congenital or acquired, is, in fact, one of the main causes of preventable childhood blindness which affects around 200,000 children worldwide, with a prevalence ranging from three to six children per 10,000 live births.
Congenital and acquired cataracts
Cataracts in children are defined:
–congenital (child) if detected within the first year of age;
–Retrieved (juvenile) if subsequently detected.
The underlying causes of the occurrence of paediatric cataracts have been the subject of much research. To determine the aetiology, it is first useful to make a distinction between bilateral and unilateral cataracts.
The cataract bilateral congenital almost always has a genetic basis (hereditary or linked to a mutation), but can also be secondary to systemic disorders such as metabolic disorders (galactosemia, Wilson's disease, hypocalcaemia and diabetes) or syndromes, the most common being trisomy 21. Certain intrauterine infections, including rubella, herpes simplex, toxoplasmosis, chickenpox and syphilis are another cause of congenital cataracts.
Le unilateral cataractson the other hand, are generally not inherited or associated with a systemic disease, but are the result of local dysgenesis (imperfect formation of an organ) or may be associated with ocular dysgenesiassuch as the persistent foetal vascularisation syndrome (PFV). Finally, a traumatic event (physical or chemical) is a common cause of paediatric cataracts.
Regardless of the aetiology of the disease the early diagnosis and timely treatment are essential to prevent the development of irreversible amblyopia (reduced visual function in one eye) from stimulus deprivation. The management of paediatric cataract depends on the age of onset, laterality (mono or bilateral), morphology and association with other ocular comorbidities and systemic.
Diagnosis
The factors to be taken into account when screening the child are:
1) family anamnesis positive for congenital cataract or other associated diseases;
2) low weight at birth;
3) red reflex anomalyThis test, performed in hospital or by the paediatrician at the first visit, is used to assess the transparency of the dioptric media. A light is directed into the child's eye and the absence of a reflection is symptomatic of a problem.
In the case of a suspected cataract, a specialist eye examination is conducted in order to ascertain the diagnosis and assess the degree of visual impairment. After a specific morphological diagnosis has been made, a decision can be made on how to intervene.
Treatment
The main treatment is surgerybut not all paediatric cataracts require surgery. A small, partial or paracentral cataract can be managed with monitoring.
If the cataract is considered to be significant in terms of visual function, surgery is the only option. The main indications for cataract surgery include:
–central cataractvisually significant, larger than 3 mm in diameter;
–dense nuclear cataract;
-cataracts obstructing the view of the ocular fundus;
-cataract associated with strabismus and abnormal eye movements.
The timing of the intervention is crucial for the subsequent visual development of the child. In fact, most experts recommend surgery within the first two months of life.
The surgical techniques applied are varied and depend on the age of the child; the operated patient is rendered aphakic (without the lens) by the primary operation, but the removed lens can be replaced by an artificial intraocular lens (IOL).
Technological advances have made cataract surgery in children safer and faster. The management of paediatric cataracts has progressed rapidly over the past decade due to safer anaesthesia, optimised IOL design, easy estimation and calculation of lens power, and increased knowledge of neurobiology and genetics.
Source
Dr. Carmelo Chines
Direttore responsabile
English 
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