Decrease of visual acuity in patients with clear media and normal fundi. Objective screening methods for differentiation and documentation.

For differentiation of unilateral reduction of visual acuity in patients with clear media and normal fundi, the Swinging Flashlight Test was used. Optic neuropathies as a rule give pathological results. On the other hand refraction scotomas, functional amblyopias and malingering produce a normal outcome of this test in general. For documentation of afferent pupillary defects a photographic method is described. Electronystagmography is advocated as a method for detection of malingerers and neurotics among patients complaining of acute uni- or bilateral visual acuity reduction. Optokinetic nystagmus is recorded using Bangerter's filters in front of the patient's eye. This method allows a certain estimation of the visual acuity.