RED SQUARE TEST FOR VISUAL-FIELD SCREENING - A SENSITIVE AND SIMPLE BEDSIDE TEST

A reliable bedside test for screening of visual field defects is a val uable tool in the examination of patients with a putative disease affe cting the sensory visual pathways. Conventional methods such as Donder s' confrontation method, counting fingers in the visual field peripher y, ot two-hand confrontation are not sufficiently sensitive to detect minor but nevertheless serious visual field defects. More sensitive me thods requiring only simple tools are also described. In this study, a test card wvith four red squares surrounding a fixation target, a bla ck dot, with a total test area of about 11 x 12.5 degrees at a distanc e of 30 cm, was designed for testing experience of red colour saturati on in four quadrants, red square test. The Goldmann visual held was us ed as reference. 125 consecutive patients with pituitary adenoma (159 eyes), craniopharyngeoma (9 eyes), meningeoma (21 eyes), vascular hemi sphere lesion (40 eyes), hemisphere tumour (IO eyes) and hemisphere ab scess (2 eyes) were examined. The Goldmann visual field and red square test were pathological in pituitary adenomas in 35%, in craniopharyng eomas in 44%, in meningeomas in 52% and in hemisphere tumours or absce ss in 100% of the eyes. Among these, no false-normal or false-patholog ical tests were found. However, in vascular hemisphere disease the cor responding figures were Goldmann visual field 90% and red square test 85%. The 5% difference (4 eyes) was due to Goldmann visual field defec ts strictly peripheral to the central 15 degrees. These defects were e asily diagnosed with two-hand confrontation and were due to anterior o ccipital lobe infarction. The red square test is a sensitive and quick method for visual field screening. And, hitherto it seems to be the m ost simple of reliable visual field screening bedside tests described.