Final answer:
The CT scan of a 65-year-old diabetic patient with left-sided neurological deficits is likely to show evidence of a right-sided cerebral infarction or hemorrhage, as well as signs of increased intracranial pressure, such as right uncal herniation affecting the third cranial nerve.
Step-by-step explanation:
A 65-year-old diabetic patient presents to the Emergency Department (ED) with acute left-sided weakness, right gaze deviation, left hemiplegia, left hemisensory deficit, and left homonymous hemianopsia. After 12 hours, the patient becomes unconscious, and the left pupil is enlarged and unreactive.
The clinical presentation suggests a right-sided cerebral stroke, possibly due to a large vessel occlusion or hemorrhage, causing increased intracranial pressure on the opposite side.
A CT scan is likely to show evidence of cerebral infarction or intracranial hemorrhage on the right side, which could include areas of low density in the case of ischemic stroke or high density in the case of hemorrhage. The enlargement and non-reactivity of the left pupil also point towards a possible right uncal herniation, secondary to the mass effect of cerebral edema or hematomas, disturbing the third cranial nerve on the same side.