Final answer:
An orbital fracture is the most likely diagnosis when a patient has double vision and deformity around the orbital area due to an acute injury. This condition affects nerves passing through the superior orbital fissure and differs from problems like bilateral hemianopia, which involves a growth pressing against the optic chiasm.
Step-by-step explanation:
When a patient experiences facial trauma and complains of double vision, combined with the presence of a deformity around the left orbital area, the most likely diagnosis would be an orbital fracture. Double vision, or diplopia, along with signs of physical trauma near the eye socket could indicate that the bones surrounding the eye have been damaged. It's important to consider the anatomy of the region. The superior orbital fissure, a significant structure affected in orbital fractures, is an opening on the anterior wall of the middle cranial fossa that allows passage for several cranial nerves that control eye movements.
An orbital fracture can affect these nerves and muscles, leading to visual disturbances. To contrast, other conditions like corneal abrasion, mandibular injury, or mastoid fracture do not typically result in double vision due to an orbital deformity. The pathology behind this presentation is markedly different from other vision problems like bilateral hemianopia, where the cause is not related to an acute injury but rather to a growth pressing against the optic chiasm affecting the visual field.