What’s the Hirschberg test?
This is a test for determining if the eyes are in alignment, typically done in young children who may be hard to do formal cover testing. You shine a light at the eyes and observe where the light reflex is located in reference to the pupil.
In general, for every mm that the light is decentered, the eye is turned about 15 diopters (7 degrees from center).
This is obviously not the most accurate method for measuring strabismus, but sometimes this is all you can get. There are cases where the Hirschberg seems abnormal, but the patient doesn’t have strabismus. For example, if a patient has a temporally dragged macula (this can occur from retinopathy of prematurity) then their eye may have to turn slightly outward to center the vision. Thus, they “appear” exotropic, but the cross-cover test shows everything is fine.
Confused, yet? Don’t worry, as tropias and phorias can be difficult, which is why we have pediatric and neuroophthalmology sub-specialties!
its has few but very very important two points. the info is really very useful.
how is cross-cover test done? as well as the cover-uncover? what’s the difference between the two? thanks..
nice description about test but not complete it should also tell about the degree of deviation
Kuch samjh nae aya anyways do pray for me
Thank you, very helpful and reassuring.
very helpful indeed,cnt believe i have just understood the hirschberg in seconds yet it was taking me hours of continously failing
As shown by Ndlovu et al (2011)the Hirschberg Test can also be used to detect an erraneous fixation in patients with schizophrenia: here the deviating eye does not move to fixate the target when the other eye is covered, as in the Cover Test proving strabismus. For details see my above homepage.
great image to aid understanding! thank you