Final answer:
An orbital fracture can lead to double vision, decreased vision, and loss of sensation in the face, while a pituitary tumor may result in loss of peripheral vision due to compression of the optic chiasm.
Step-by-step explanation:
Double vision, a marked decrease in vision, or a loss of sensation above the eyebrow, over the cheek, or in the upper lip may be caused by an orbital fracture. Such injuries can affect the bones surrounding the eye, disrupting the normal function of the eye and associated structures. An orbital fracture can lead to symptoms including double vision (diplopia), decreased vision, and loss of sensation in the areas supplied by nerves that travel through the facial and orbital bones.
Bilateral hemianopia, the loss of lateral peripheral vision, is a different condition resulting from a compression of the optic chiasm, often by a pituitary tumor. Unlike an orbital fracture, in bilateral hemianopia, the superior and inferior peripheral fields are not lost, and the cause is not a direct injury to the eye but rather a problem within the visual pathway in the brain.