What Is the Hirschberg Test?

The Hirschberg test is a quick, noninvasive screening for strabismus, a condition in which the eyes are out of alignment. Care providers can perform this test on patients of any age as part of a routine eye exam. If signs of strabismus are identified, some additional testing may be recommended to learn more about the situation and develop treatment recommendations. These can vary, depending on the cause.

In the test, the care provider asks the patient to focus straight ahead on a target, shining a light into the eyes. The light should reflect from the middle of the cornea, right over the pupil, in people with eyes positioned correctly. If it wanders across the eye, this indicates that the patient’s eyes are not quite aligned. Deviations on the Hirschberg test can reveal strabismus that may not be apparent with the naked eye. The light may land squarely in one pupil and above, below, or to the side of the other.

When care providers note that the eyes appear to be out of alignment, they can measure the degree of deviation to determine the severity of strabismus. The results of the Hirschberg test can be noted on the patient’s chart. Other tests with minimally invasive approaches are available to confirm the finding, as the care provider doesn’t want to alarm the patient if the diagnosis is incorrect. A patient history can also provide important information, as in some instances the eyes may appear to be out of position in the Hirschberg test, but there are extenuating circumstances that explain the situation.

Primary diagnosis of strabismus can involve the Hirschberg test along with other procedures to check on eye health. Once the patient enters treatment, follow-up testing may be necessary. This can help a care provider determine if a treatment approach is effective, and how well the patient responds to it. Some patients benefit from eye exercises, for example, while others may need glasses, eye patching, or medications to treat the condition. It is important to intervene quickly, because the longer strabismus is allowed to persist, the more complications it can cause.

Parents referred to an eye specialist after a pediatrician notices something of concern during an examination should not panic. Eye care for young children is extremely important, and a pediatrician may want to be safe rather than sorry. The eye doctor can explain which procedures are recommended or necessary to find out if a problem is present. Findings can be discussed with the parents to provide them with information about treatment options, if a problem is identified and the physician feels the child needs treatment.