Pupils, or dark circles, are usually the same size. Unequal students (mismatch) can be a sign of a medical problem.
Certain medicines placed in the eye may change the size of the pupils, but the effect should usually wear off within a few hours. Ongoing discrepancies can be caused by a variety of conditions, including multiple sclerosis, cranial nerve injury, and stroke.
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symptoms
When you look in the mirror, you may notice that your pupils are different sizes. Or you may notice that other people’s pupils are not the same size.
In some cases, uneven pupils may be associated with other symptoms.
Possible symptoms associated with unequal pupil size include:
Numbness or weakness on one side of the face or body Blurred vision or loss of vision in one or both eyes Drooping eyelids (or both eyelids) Headache or eye pain Change in consciousness
Types of unequal pupils
The pupils of the eye normally constrict (reduce in size) in response to light and when looking at nearby objects. These responses should occur symmetrically (the same way in both eyes), even if there are slight differences in pupil size from birth. When light shines on one eye, the other eye also contracts.
Possible causes of abnormal pupil size include:
Fixed: Pupil size is not normal and may not constrict or dilate properly. Responsiveness: Abnormally sized pupils show at least some change with exposure to light or changes in viewing distance. Dilated: One or both pupils are abnormally large. Constriction: One or both pupils are abnormally small.
cause
Some people are born with unequal pupils. This can be a harmless physical feature or a sign of an eye or brain problem. Babies with discrepancies should undergo an initial physical examination to determine if a serious cause needs to be addressed.
Many illnesses can cause student inequality. Possible causes of unequal student numbers include:
Multiple sclerosis (MS): MS is a chronic neurological disease that causes symptoms that affect vision, movement, and sensation. Cranial nerve damage: This can occur due to a stroke (blockage of blood flow or bleeding in the brain), a brain aneurysm (a defect in a blood vessel), or a brain tumor. Inflammation: Infections that affect the eyes or cranial nerves can cause anisotropia. MS and sarcoidosisyou can also do this. Trauma: Injuries that affect the eyes or brain can cause pupils to become uneven. Glaucoma: When glaucoma puts pressure on one eye, it can cause one pupil to dilate. Increased intracranial pressure: This can be caused by a brain tumor, meningitis (inflammation of the fluid around the brain), or stroke. Vision loss: Significant vision loss can affect pupil size and responsiveness. Migraine: Although not common, migraines can cause discord. Seizures: Seizures (interruptions in electrical activity in the brain) may cause changes in the pupils, which may or may not be equal.
Diabetic oculomotor nerve palsy: This rare complication of diabetes can cause droopy eyelids, double vision, and anisocoria.
Surgery: Eye surgery can change the size of your pupils, and this can be permanent. Coma or brain death: Severe brain damage can cause changes in pupil size and responsiveness.
How does anisocoria occur?
Pupil size and responsiveness are controlled by coordination between vision (controlled by the 2nd cranial nerve), the muscles that move the pupil opening, and the nerves that control these muscles (the 3rd cranial nerve). Injuries, diseases, or chemicals that interfere with one or more of these functions can cause anisobaria.
What is Horner syndrome?
Horner syndrome includes drooping eyelids, constricted pupils, decreased sweating, and sometimes redness of the eyes. This can be caused by diseases such as tumors, upper spine disease, stroke, neck or chest disease, and MS, which can affect the sympathetic stimulation of the nerves that control the pupils.
What medicines can cause student inequality?
Many drugs can affect pupil size and cause anisotropia. Some of these are inserted into the eye to dilate (enlarge) the pupil as part of an eye exam or eye surgery. Many drugs have the potential to cause changes in pupil size or anisotropia as a side effect.
Medications that can cause pupil inequality include:
Antihistamines: Singulair (Montelukast), Zyrtec (Cetirizine), etc.
Scopolamine patch (Scopolamine)
Antidepressants: Elavil (amitriptyline), Pamelol (nortriptyline), etc.
Flomax (tamsulosin HCL) and other alpha-1 blockers used to treat enlarged prostate
Antipsychotics: Chlorpromazine, Melalil (thioridazine), etc.
Antispasmodics used to treat gastrointestinal problems: Bentyl (dicyclomine), Levsin (hyoscyamine), etc.
Ditropan, Oxytrol (Oxybutynin) used to treat overactive bladder
Cordarone, Passerone (Amiodarone) is used to treat arrhythmia (irregular heartbeat).
Anesthetics used during surgery, such as ketamine
During an eye exam or eye surgery, atropine, homatropine, cyclopentolate, or phenylephrine eye drops are placed in the eye to dilate the eye.
Accidental contact with topical medications such as antiperspirants and anesthetics
In addition to medications, some recreational drugs can also cause changes in pupil size. For example, alcohol, marijuana, or cocaine use can cause the pupils to dilate, and opiates can cause the pupils to constrict or dilate. These effects are usually symmetrical, but may not be equal.
What drugs cause unequal pupils?
The drug’s effect on pupil size is temporary and disappears within minutes, hours, or days. It depends on the drug, the dose, and the person’s ability to break down and remove the drug from the body.
diagnosis
Diagnosis of the cause of pupil asymmetry requires a comprehensive physical examination, including an ophthalmological and neurological examination. Diagnostic tests are often also required.
Your health care provider will determine if you have vision problems. It also defines whether the pupils are fixed or reactive, and whether any of the pupils are dilated or constricted.
Other symptoms and signs can help identify an underlying medical condition. For example, a severe headache may indicate increased intracranial pressure, and a fever and stiff shoulders may be signs of meningitis.
Diagnostic tests may include:
Brain imaging tests, such as computed tomography (CT), magnetic resonance imaging (MRI), and angiography, can identify problems with the brain or blood vessels in the brain. Visual evoked potentials can identify signs of eye disease or MS.
process
Unequal student treatment varies. In some situations, pupil size can indicate a serious medical emergency. That’s why you need prompt medical attention.
Treatment does not necessarily focus on making the pupils look equal. Instead, the priority of treatment is to manage the underlying condition.
Treatment options include:
Disease-modifying drugs to treat MS Medications to lower intracranial pressure (which may include high-dose steroids) Acute stroke treatments such as blood thinners Antibiotics to treat bacterial meningitis Brain Treatments to reduce intracranial pressure, such as removal of spinal fluid (CSF), surgical removal of the tumor, and placement of a ventricular shunt to prevent increased intracranial pressure.
When should you see a health care provider?
If your pupils suddenly become uneven, you should see your health care provider right away. This could be a sign of a medical emergency.
If you have a chronic condition that can cause pupil imbalance, such as MS or a ventricular shunt, discuss a plan of action with your health care provider. The plan includes what symptoms to call and who to call.
summary
Pupillary inequality (anthocoria) has various causes. It can be a natural physical characteristic, the temporary effects of drugs, alcohol, or illegal substances, or a sign of neurological or eye disease.
If new discrepancies occur, it is important to see a doctor. The diagnostic process includes a detailed eye exam and neurological exam. If the pupil size discrepancy has a medical cause, treatment is required.