The monocular vertical prim diociation tet

Purpoe To determine if the monocular vertical prim diociation tet can differentiate between organic and nonorganic viual lo. Deign A propective, ingle-maked obervational tudy. Method Three intitutional neuro-ophthalmology practice. Group 1 conited of 30 normal control. Group 2 included 30 patient with known organic viual lo. Group 3 contained 35 patient with upected nonorganic monocular viual lo. Participant were aked to decribe what they aw while viewing a ingle nellen letter when a 4-prim diopter bae-down prim wa placed in front of their better eye. Outcome wa meaured by whether the participant ee one or two letter with the prim in place. Reult Viion-appropriate reult were given by all member of Group 1 (two image) and by all member of Group 2 (one image). Two image were een by 31 of 35 member of Group 3, indicating nonorganic viual lo. The other 4 ubject in Group 3 aw one image; each wa ubequently found to have occult pathology. Concluion The vertical prim tet quickly differentiate organic from nonorganic monocular viual acuity lo.