A woman with visual problems and amenorrhea due to a pituitary tumor is most likely to present with which visual abnormality?

The situation described involves a woman presenting with visual problems and amenorrhea, which are indicative of a pituitary tumor. The visual abnormality associated with pituitary tumors is typically bitemporal hemianopia. This occurs because the tumor can compress the optic chiasm, where the optic nerves cross.

When the optic chiasm is compressed, it affects the crossing fibers that carry visual information from the nasal halves of each retina. As a result, this leads to a loss of vision in the outer (temporal) fields of both eyes, resulting in bitemporal hemianopia. This pattern is specifically characteristic of pituitary tumors because of their location relative to the optic chiasm.

The other visual abnormalities mentioned do not typically arise from pituitary tumors. For instance, homonymous hemianopia involves loss of the same field in both eyes and is more often associated with lesions in the optic tracts or occipital lobe. Tunnel vision describes a constricted visual field, which does not directly correlate with the classic presentation of a pituitary tumor. Homonymous lower quadrantanopia, similar to homonymous hemianopia, pertains to a different type of brain lesion affecting the visual pathways, which again is not linked to