Anisocoria in Chicago Ridge, IL, Tinley Park, IL, and Munster, IN

“Anisos” in Greek means “unequal”, while “kore” is Greek for “pupil”, so anisocoria refers to unequal sized pupils. Slight anisocoria (around 1 mm of asymmetry) is normal in around 1 in 5 people (physiologic anisocoria). Pathologic (abnormal) anisocoria occurs when there are either mechanical, structural, or neurological problems with the iris.

One critical question in determining the cause of anisocoria is to decide whether the larger pupil is “too big” or if the smaller pupil “doesn’t get big enough”. The iris is the colored donut-shaped muscle, which constricts in reaction to light (miosis) and relaxes or dilates in the dark (mydriasys).

If there is a problem with pupil constriction the anisocoria will be greater in bright light. Conversely, if the pupil asymmetry is greatest in relative darkness, there must be a problem with pupil dilation (physiologic anisocoria usually has similar asymmetry in dark or light conditions). If you or your child has anisocoria, a careful eye examination is important; call for an appointment at Ticho Eye Associates.

There are many causes of unequal pupils, some temporary, some permanent; many causes are benign, while others can indicate serious problems. A few causes of anisocoria are:

• Iris trauma (causes asymmetries in pupil constriction)

• Adie’s tonic pupil syndrome (sluggish pupillary constriction, usually in young women)

• Third cranial nerve palsy (associated with difficulty moving the affected eye properly)

• Use of certain eyedrops (pupil dilation is common in complete eye examinations)

• Uveitis (inflammation inside the eye may make pupil constriction sluggish or sticky)

• Horner syndrome (usually benign, but occasionally associated with cancer)

Your Ticho Eye Associates doctor can help diagnose the different causes of anisocoria. Please arrange for a thorough exam at one of our offices in Chicago Ridge, IL, Tinley Park, IL, and Munster, IN.

In Horner syndrome, the involved pupil does not dilate as well as the other eye. There is almost always eyelid asymmetry as well, with both the upper lid being a little low (ptosis) and the lower lid being a little high (inverse ptosis). This eyelid asymmetry makes the eye look smaller than the other side.

Horner syndrome can appear from birth (congenital) or show up later (acquired). In congenital cases, Horner syndrome may also show asymmetry in iris color (lighter in color than the uninvolved side = heterochromia) or decreased facial sweating on the affected side (anhydrosis). While present from birth, congenital Horner syndrome is not hereditary.

Acquired Horner syndrome may appear following neck trauma or surgery, or an abnormality in the chest, neck, or brain. Rarely, acquired Horner syndrome in young children can be a sign of a malignant tumor called neuroblastoma. If neuroblastoma is suspected, further investigation with urine tests or radiologic studies may be indicated. If your child has anisocoria, please arrange for a prompt evaluation at one of the Ticho Eye Associates facilities in Chicago Ridge, IL, Tinley Park, IL, and Munster, IN.

The best way to determine whether you have anisocoria is to undergo a comprehensive eye exam at Ticho Eye Associates. During this time, we will evaluate the size of the pupils and how they react to bright and dim light. A thorough examination of the eyelids and the internal eye structures will also help guide a diagnosis. Based on the findings, we may perform additional tests, order lab work, or take x-rays. Once a diagnosis has been made, we can discuss your treatment options. The treatment process will vary for everyone as it's dependent on the underlying cause of your anisocoria.

Have you been experiencing eye pain, blurred vision, frequent headaches, fever, or droopy eyelids? These are all common signs of anisocoria. While some cases of unequal pupils are temporary and considered normal, others may be directly related to an eye health problem that may require professional treatment. Contact Ticho Eye Associates in Chicago Ridge, IL, Tinley Park, IL, or Munster, IN to set up an appointment.