Progressive Bitemporal Hemianopsia: An Unusual Presentation of Non-Organic Visual Field Loss.

Summary: Functional, progressive, bitemporal hemianopsia can be confirmed by the persistence of the hemianopic field defect with both eyes open. This is because the nasal hemifield of each eye corresponds to the temporal hemifield in the contralateral eye. Thus, a patient with a monocular hemianopic or altitudinal VFD (e.g., junctional scotoma of Traquair) or a bitemporal hemianopsia, if organic, will have a normal visual field if tested with both eyes open. In contrast, a homonymous hemianopsia will produce a hemianopic result on both eyes open testing regardless of whether the VFD is organic or not (FVD). Clinicians should be aware which VFD can and cannot be confirmed as FVD with the both eyes open testing of visual field technique