Congenital glaucoma is due to inadequate development of the structures that comprise the drainage system of the aqueous humour and, under normal conditions, allows its exit through the tabecular meshwork, which causes a significant increase in intraocular pressure (IOP).
It is not a frequent disease and is usually present at any time during the first three years of the child's life, affecting a large percentage of both eyes, although not to the same degree of intensity. However, not all cases of congenital glaucoma are the same, but are classified into two types:
- Primary. It is the most frequent and, if not treated properly or the child does not respond to treatment, can cause total loss of vision of the affected eye.
- Secondary. These are those cases of glaucoma that are associated with equally congenital or hereditary ocular malformations, such as aniridia, Axenfel´s syndrome or Peters' anomaly. It is also associated with malformations of other organs, traumas, congenital cataracts or infections suffered by the mother during pregnancy, among other possible causes.
In the case of primary congenital glaucoma, the symptoms are very characteristic, since the cornea loses its transparency and the eye becomes large, appearing to protrude. This is known by the name of hydrophthalmia or buphthalmia, and the cornea may take on a violet colouration.
If the glaucoma is secondary, the patient´s symptoms are different from the primary one, with a clear excess of tearing, the cornea becomes opaque or closes the eyes when it is subjected to intense light (photophobia).
However, such symptoms may be common to other complaints, so an in-depth examination of the eye will be necessary to confirm the diagnosis.
Depending on the type of glaucoma, it may be more or less aggressive. But surgery is always the only possible option, although in some cases a prior pharmacological treatment is instituted to reduce and, if possible, control IOP. It is noted that if the diagnosis occurs at the time of birth, which is the most serious situation, surgery should be immediate.
Surgery is performed on one eye and then on the other, if they are affected by the disease Similarly, the choice of surgical technique will depend on the degree of opacity of the cornea and whether the angle of the cornea with the iris is altered or not.
If the cornea is still transparent, a gonotiomy can be carried out, and, if not, the chosen technique will be trabeculectomy.
A goniotomy is used when the cornea is transparent and the cause of glaucoma is the obstruction of the drainage ducts of the aqueous humour by the presence of embryonic tissue, which is withdrawn after a small incision is made in the lateral part of the cornea to access the anterior chamber.
Trabeculectomy is the technique of choice when the cornea has become opaque, although it may also be used when it is not. With it, a new drainage path is opened so that the aqueous humour can leave the interior of the anterior chamber. In this case the incision is made in the sclera.
Results of the operation
Surgical treatment of congenital glaucoma has good results in 60-80% of cases, although there is always the possibility of reoperation in order to reduce IOP or to implant a drainage valve, a small tube through which aqueous humour can exit the posterior camera.
On the other hand, serious complications, such as cataract formation, retinal detachment or corneal alterations, as well as ocular inflammation and eventual infections, can be considered. Likewise, children often present visual disturbances, such as myopia, amblyopia or strabismus. 80% of them become adults with an acceptable visual ability.
It is important to note that in cases where surgical treatment has been delayed or in those where IOP cannot be reduced and controlled, total loss of vision can occur