Q: I recently had a seven-year-old patient who said she was seeing double. Is there something serious going on? How do I handle it?

“When an older child (above the age of five) comes in with diplopia or strabismus that has never been documented before, the number one thing that the optometrist has to determine is whether it was of recent onset or recent discovery. In other words, is it new or longstanding?” says Valerie M. Kattouf, O.D., chief of pediatrics and associate professor at the Illinois College of Optometry.

“I see this every day with two-, three- and four-year-olds, but when I see this in a seven-year-old, my antennae go up,” Dr. Kattouf says of this case. It’s unusual for a seven-year-old to have undiscovered, longstanding and constant diplopia. On the other hand, sudden onset suggests pathology.

Rest assured that you have the tools to figure it out, she says: 



Diplopia in children very often relates to strabismus. Usually, it’s not of recent onset but a recent discovery. This child, for instance, demonstrates intermittent exotropia.
History. Start by asking the patient and/or the parent about the occurrence of the diplopia. Has it developed over time, or did it appear suddenly? Is it constant? Is it horizontal, vertical or both? Is there any past history of diplopia?

Testing. Use a cover test to evaluate alignment and determine strabismus. If so, is it present in all gazes? Are there any muscle restrictions? Use the stereopsis test to determine whether the strabismus is of recent onset or is longstanding. A stereopsis response with prism neutralization indicates recent diplopia. A suppression response (no stereopsis) indicates that it is longstanding.

Dilation. “It’s rare that you’ll dilate the patient and see a retinal lesion or an optic nerve anomaly that is causing the diplopia,” Dr. Kattouf says. But that doesn’t mean you’ll never see such an etiology—and it’s certainly one that you don’t want to miss—so definitely dilate the patient. 

Still, “diplopia in children almost universally relates to strabismus. I can’t tell you how often these cases are recent discovery and not recent onset,” Dr. Kattouf says. “But if it is recent onset, you have to consider a neurologic problem.”

That means a referral for an MRI or CT scan.

When bringing this up to the parents, “I try not to be too vague, but not too specific either,” Dr. Kattouf says. “I say, ‘We want to make sure that there’s no underlying disease process that’s causing this, so we’re going to refer you for a neurologic scan.’ And that’s usually the most I’ll say initially, because you don’t want to plant the seed of an idea that it’s a tumor. Often the scan comes back completely clear.”

If it does, then it’s very likely that the child’s vision problem merely is something that caused decompensation over time. “In that case, you treat it just as you would a more longstanding strabismus,” she says.

To that end, you certainly can handle the case on your own. “Sometimes, the answer might be as simple as a spectacle correction to control the strabismus,” Dr. Kattouf says. “The next step is prism correction, if possible. Alternatively, some patients respond to vision therapy. Lastly, some children may do best with a surgical referral.”