Anisocoria is a disorder of the eye characterized by the uneven size of the pupils. It is a rare disorder of the eye, unlike myopia, which is quite common. It can in some cases, be entirely harmless while in other, indicate certain serious underlying conditions. Also Read: Myopia – Causes, Symptoms And Treatment

Pupils are the round, black circles in the center of the eyes. In a normal healthy individual, the pupils are usually of the same size. However, if an individual has anisocoria, the size of the pupil in one eye is significantly larger than the pupil in the other eye.

Several factors cause anisocoria. In certain instances, a person might be born with the syndrome of the mismatched size of pupils of the eyes. It could also suddenly arise due to direct trauma to the eye as a result of injuries or accidents or even inflamed optic nerve.

Severe injuries to the brain also give rise to anisocoria, like in the case of concussions, bleeding in the skull, brain tumours, aneurysm, meningitis and seizures.

In some cases, pupils may be uneven in size only for a brief period of time and then return to their normal original size. If this happens, with no associated pain or discomfort, then anisocoria in that person is not a grave occurrence.

However, if the contrast in the size of the pupils is very prominent and they do not become even over time, then anisocoria indicates a serious underlying condition of the nerves in the eyes and brain or other parts of the skull, in the affected individual. It is recommended to seek immediate medical care in such scenarios, to ensure that the relevant treatment measures are provided and the patient recovers completely.


The distinguishing symptoms of anisocoria comprise:

Diagnosis And Treatment

The eye doctor, also known as an ophthalmologist, will initially conduct an eye exam, to examine if the person is experiencing any eye pain, sensitivity to light, headache while viewing small objects and any other problems with vision. Also Read: Computer Vision Syndrome: Causes, Symptoms And Treatment

After taking a complete medical history of the patient, the healthcare provider also carries out a complete blood profile and certain imaging tests like MRI, CT scans and X Rays, to determine if any underlying head injury might be the cause of anisocoria.

Once the exact cause of anisocoria is confirmed, the doctor initiates appropriate treatment measures.

In case an infection is triggering uneven pupil size in the patient, then antibiotics or antivirals in the form of eye drops are prescribed, to combat the microbes and rectify the condition in the eyes.

However, if any injury or trauma to the brain is detected due to abnormal growths, then the doctor will carry out a surgery to remove the tumour and restore the normal size of pupils and proper vision in the patient.