Ectopia Pupil

Ectopic pupils (ancient Greek έκ- “from”, τόπος “place”) is a pathological condition in which the pupil of the eye cannot voluntarily change its diameter depending on the level of illumination, i.e. the pupil does not react to light.

It is most often observed in young people and is characterized by an unusual location of the pupil on a wide fundus. Normally, the photosensitive membrane of the posterior pole (retina) is symmetrically attached to the inner surface of the lens through a pigment layer (fovea), which ensures the normal location of the pupil in the center of the palpebral fissure. The reasons for the displacement of the foveal attachment can be different - disorders of the intrauterine development of the eye, trauma to the intraocular tissues, tumors, inflammatory lesions of the cells of the choroid, as well as some specific diseases, such as whooping cough or rheumatism. With ectopia, the pupils are asymmetrical, their size is slightly larger or smaller compared to the opposite side. The parallel placement of the eyeballs does not correspond to the norm, but a sunken pupil (unilateral in case of ectopia of one eye) is also not always observed. Clinical signs of ectopia are varied and depend on the degree of deviation of the foveola from its normal position. With a pronounced ectoptopic location of the pupil, diplopia is observed in the supine position; when the eyes are moved away from the lateral position, they become poorly fixed (nystagmus). In the early stages of ectopia, minor changes in the visual fields or their complete normality are often observed, but strabismus of the 2nd degree and a weaker degree (monolateral hypermetania) is quite often observed. The state of visual functions depends on the presence of an inflammatory process in the area of ​​retinal pathology