Skip to Main Content

++
Table Graphic Jump Location
Favorite Table | Download (.pdf) | Print
The Problem
“One of my child’s pupils is larger than the other.”
Common Causes
Physiological anisocoria
Horner syndrome
Iritis
Pharmacological
Other Causes
Third nerve palsy
Trauma
Congenital iris anomalies
KEY FINDINGS
History
Physiological anisocoria
Mild asymmetry
Variable (pupils sometimes equal)
Horner syndrome
Pupils always unequal
Worse in dim light
Ptosis on side of smaller pupil
Possible decreased sweating of face on affected side
Unequal pupil color in congenital or early acquired cases
Associated with some systemic disorders
Neuroblastoma
Thoracic or cervical surgery
Birth trauma with cervical injury
Trauma
History of direct ocular injury
Iritis
History of juvenile idiopathic arthritis
Ocular pain, redness
Pharmacological
Exposure to topical medications or plants that affect pupil
Third nerve palsy
Strabismus, ptosis
Systemic diseases associated with third nerve palsy
Examination
Physiological anisocoria
Difference between pupils less than 1.0 mm
Variable, sometimes equal
Greater in dim light
Horner syndrome
Asymmetry greater in dim light
Mild ptosis on affected side
Possible unequal sweating on affected side
Possible difference in iris pigment (heterochromia)
Trauma
Affected pupil may be smaller or larger than normal pupil
Other signs of ocular trauma
Iritis
Pupil nonreactive, possibly irregular
Possible cataract
++

Mild (<0.5 mm) anisocoria in young children is usually normal, particularly if it is variable. Anisocoria associated with other disorders, particularly Horner syndrome and third nerve palsy, is not an isolated finding. If a patient has ptosis along with anisocoria, referral to a pediatric ophthalmologist is indicated for evaluation of possible Horner syndrome or third nerve palsy. If the pupil does not react at all, referral is also indicated.

++

What Shouldn’t Be Missed

++

Horner syndrome, particularly in older children, may result from serious diseases such as neuroblastoma. These patients require evaluation to look for these problems. Children with iritis secondary to juvenile idiopathic arthritis (JIA) may have no symptoms of ocular discomfort despite severe inflammation. In some of these patients, abnormal pupils due to scarring of the iris may be the first abnormality noted.

+

  • 1. Physiological anisocoria. Mildly asymmetric pupils may occur in otherwise normal infants. This may be familial. The anisocoria is more noticeable in dim light. The hallmark of physiological anisocoria is variability, with the pupils sometimes appearing equal. Physiological anisocoria does not cause any problems with development of vision.
  • 2. Horner syndrome. Horner syndrome occurs due to interruption of the oculosympathetic chain that begins in the hypothalamus, travels through the spinal cord to the thorax, and ascends along the internal carotid artery to the orbit. Lesions anywhere along this pathway may cause Horner syndrome. The syndrome is characterized by anisocoria (pupil smaller on the affected side), mild ptosis, and anhidrosis (decreased sweating on the affected side of the face) (Figure 18–1). It typically does not cause vision problems. It is important because of its association with other systemic conditions.
  • 3. Iritis. Most patients with iritis (intraocular inflammation) have marked eye discomfort and seek medical attention because of this complaint. For unknown reasons, children with iritis associated with JIA usually do not experience significant eye pain. Because of this, even severe inflammation may go unnoticed until substantial eye damage is present. Children with JIA sometimes present with nonreactive pupils due to scarring of the iris to the lens capsule (Figure 18–2).
  • 4. Pharmacological. Several eye drops or ...

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.

Ok

About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessPediatrics Full Site: One-Year Subscription

Connect to the full suite of AccessPediatrics content and resources including 20+ textbooks such as Rudolph’s Pediatrics and The Pediatric Practice series, high-quality procedural videos, images, and animations, interactive board review, an integrated pediatric drug database, and more.

$595 USD
Buy Now

Pay Per View: Timed Access to all of AccessPediatrics

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.