RADIO-INDUCED CATARACT IN A CHILD WITH A CEREBRAL MENINGIOMA

There are many causes of cataracts. They can be post-traumatic, congenital, senile…, but also post-radiation.

In what follows, we will detail a case of a radio-induced cataract.

We received a 12 years-old child in the ophthalmology department. She had a follow-up, with oncologists, for a right temporal meningioma, for which, she benefited of several sessions of radiotherapy with a cumulative dose of 56 grays. The child consults for a progressive decline in visual acuity, appearing one and a half years after radiotherapy. 

On clinical examination, in both eyes, we found visual acuities of 1/10, clear corneas and anterior segments showing anterior and posterior polar cataracts. At the fundus, the excavations were physiological, good macular reflections and there were no signs of radio-induced retinopathy.

Thus, we decided, after having carried out a pre-anesthetic assessment, to do a phacoemulsification of her cataract in the right eye and then 1 month later in the left eye. 

The patient currently has a secondary cataract in her right eye for which she will benefit of a Yag laser.

Cataracts induced by ionizing radiations are due to numerous metabolic disorders which may affect some elements contained in the lens. The drop in glutathione (an antioxidant), the sudden onset of low molecular weight protein loss can coincide with the maturity of the opacification. There is also a large accumulation of molecular mass aggregates. These events will lead to a disruption of the ionic and phosphocalcic balances of the lens as well as glucose metabolism. There will be other cellular modifications. These changes will lead to the formation of abnormal lens fibers which will migrate to the subcapsular regions leading to opacifications of these regions. The cumulative threshold dose for locoregional radiotherapy is> 5Gy.

The management of these cataracts is similar to that of senile cataracts. The secondary opacification rate would be less frequent.

The radiation-induced cataract is a rare pathology, which occurs in children, the risk of amblyopia leads us to take care of it urgently.