Brückner test is performed in a semidark room using a direct ophthalmoscope to assess the red reflex from both eyes simultaneously at a distance of approximately 1 m. The clinician can quickly determine the clarity and symmetry of the 2 red reflexes and identify potentially amblyogenic conditions such as anisometropia, isoametropia, and ocular misalignment. A strabismic eye tends to give a brighter red reflex than does the fixating eye.