I’m trying to examine an 8-year-old boy and he won’t sit still or follow any of my instructions. There is a strong family history of heterotropia. Is there anything I can do to get at least some basic eye information?
It can be difficult to examine some patients. Co-operation from the patient in the form of following your instructions to look at certain things so you can look at their eyes (ocular health, refractive status and alignment) and responding to your requests (visual acuity, stereoacuity, colour vision testing) is always helpful. Some patients cannot co-operate in the way you would like them to.
My first comment is not to blame the patient. Nothing is ever the patient’s fault especially when the patient is a child. Well, some adults who wear contact lenses bring disaster on themselves through not heeding your advice but that is not today’s theme.
My second comment is that the Brückner test can be very useful when a child patient is not being co-operative.
The first image shows how to conduct the test. With any refractive correction removed and in dim light shine a direct ophthalmoscope toward the patient’s eyes from a distance of 80 to 100 cm using a large round patch of light to illuminate both pupils simultaneously. Ask the patient to look at the centre of the light. Even patients lacking co-operation can manage to look at a bright light especially if you ask them to look for Spiderman, a Disney princess a unicorn or Lionel Messi depending on what is popular in your area with children.
As the practitioner, look through the peephole of the ophthalmoscope and dial in the focussing lens that gives a clear view of the patient’s pupils from the distance you are working at. Compare the brightness of the red reflex in each eye. If the two reflexes are equally bright, there is binocular fixation. If the reflexes are not equally bright, the darker red reflex indicates the fixing eye, and the brighter, lighter, or whiter reflex indicates the non-fixing eye:
In the second figure, the right eye has the brighter reflex and in this case, this is due to a dilated pupil.
A brighter reflex in one eye may be caused by strabismus, anisometropia, anisocoria, media opacities, or posterior pole abnormalities. The brighter eye being the affected eye is counter-intuitive. Note how this contrasts with the use of a retinoscope when the reflex of the affected eye is often the darker.
Also, note that subtle refractive error and bilaterally symmetrical refractive error will not be detected with the Brückner test.
But in those patients who are not co-operating it gives some useful and solid clinical information that can be obtained in a few seconds and relayed to the patients with a follow-up appointment booked at a time of day when the child is likely to be more co-operative.