Bitemporal hemianopia produces a loss of binocular fusion, which results in “hemifield slide.”
Permission from Dr. Schwartzman adapt/reuse image.
Visual Field Defect: Bitemporal Hemianopia
Optic Chiasm Lesion
Bitemporal hemianopia is an important exam finding because it often suggests the presence of a sellar mass, such as a pituitary adenoma or craniopharyngioma.
Often it is stated that this lesion produces a constriction of vision and a sensation of “wearing horse blinders”; however, more accurately, bitemporal hemianopia produces a loss of binocular fusion, which results in “hemifield slide.”
Common causes:
- Pituitary tumors
- Craniopharyngiomas
- Suprasellar meningiomas
- Cerebral aneurysms that affect the midline
- Hypothalamic neoplasms
- Gross 3rd ventricular dilation
- Optic chiasm gliomas