Pupils of different sizes: causes, prognosis

Pupils of different sizes are observed in humans with some ophthalmic and neurological diseases. In medicine, the symptom, which is manifested by the inequality in the size of the eye pupils, is called anisocoria. This pathology is observed when the sympathetic fibers of the eye are damaged, associated with the pupil-expanding muscle, or parasympathetic eye fibers related to the muscle responsible for the narrowing of the pupil.

Pupils of different sizes, causes of pathology

If anisocoria occurs as a result of eye trauma, in which the muscle contracting the pupil is damaged, immediately after the incident the pupil first narrows, but soon again expands, and ceases to react to accommodation and light stimuli.

Pupils of different sizes sometimes cause inflammation of the iris of the eye, the so-called iritis.

All pupil responses decrease with closed angle glaucoma as a result of ischemia of the iris of the eye. Glaucoma is accompanied by a palpable acute pain in the eyeball, the patient's vision gradually decreases.

If pupils of different sizes are more visible in bright light, then this is most likely a manifestation of parasympathetic innervation disorders. This disease causes a dilated pupil (mydriasis), and all of its reactions also weaken. Most often, mydriasis is a consequence of the lesion of the oculomotor nerve, which is accompanied by divergent strabismus, restriction of the motor functions of the eyeball, ptosis and doubling.

Different pupils in anisocoria may be a consequence of a tumor or an aneurysm compressing the oculomotor nerve.

Parasympathetic denervation (pupils of different sizes) is due to infectious inflammation of the eyes or trauma in the orbit of the ciliary ganglion.

In this case, the pupil does not react to light, but the slowed ability to accommodate (adapt) is preserved.

The syndromes of Adi and Horner

The syndrome of Adi is characterized by the fact that when you move into the distance, the pupil dilates slowly, and this, in turn, disrupts accommodation, and visual acuity is lost . This syndrome is often observed in young women and is the cause of mydriasis on one eye.

If anisocoria increases in the dark or when light is removed, then this is a manifestation of simple anisocoria or Horner's syndrome.

This syndrome is accompanied by ptosis, anhidrosis of the face (a violation of sweating) and narrowing of the pupil, and is often a consequence of violation of sympathetic innervation of the eyes. Pupils with Horner's syndrome react normally to accommodation and light.

The cause of Horner's syndrome is cancer of the upper part of the lung, damage to the trunk of the spinal cord or upper cervical spine. With Horner's syndrome, which occurred with cancer of the upper part of the lung, at the same time there are thin muscles of small hands, pains that give to the medial surface of the hands.

Pupils of different sizes are due to compression of sympathetic fibers due to thyroid cancer, due to various surgical interventions, traumas, tumors, enlarged lymph nodes at the neck, with carotid thrombosis and for other reasons.

If as a result of trauma the carotid artery cleaves, Horner's syndrome is accompanied by facial pains on the same side and disorders of cerebral circulation.

Horner's syndrome in children causes neuroblastoma in the cervical or upper thoracic part.

With simple anisocoria (essential), a small difference in the size of the pupils (no more than 0.5 mm) is quite often diagnosed.

A migraine attack sometimes causes a unilateral mydriasis. Pupils of different sizes in this case are short-lived and the pupil's reactions are completely preserved.

Different pupils are a serious reason to call a doctor, as they can be a consequence of serious illnesses.