Seeing two images of a single object is what diplopia means. This occurs when the eyes don’t align or when there’s an issue with the eye muscles or nerves, so the brain ends up receiving two separate images instead of one fused image. Diplopia can be binocular, where the double image goes away if one eye is closed, or monocular, where the double image persists even with one eye closed. The other options describe different problems: loss of color vision is a color-vision deficiency, difficulty focusing at near distances is an accommodation issue, and blurred vision without double vision is single-image blur from refraction or other causes.

Normal sensorimotor findings mean the patient has intact sensation, normal muscle tone, and symmetric movement on both sides. This reflects no focal deficits and coordinated function across the body. When everything is working normally, there shouldn’t be unilateral weakness, sensory loss, or abnormal reflex patterns. If you see asymmetric facial weakness, that points to a cranial nerve or corticobulbar tract issue rather than a normal finding. Hyperactive reflexes on one side suggest an upper motor neuron lesion affecting that side of the brain or spinal cord. Loss of sensation in a limb indicates a disruption of sensory pathways. These are signs of pathology, not baseline normalcy. So the best choice captures the idea of a healthy, balanced sensorimotor exam: intact sensation, normal tone, and movement that is symmetric bilaterally.

FAST is a quick stroke screening mnemonic used to recognize warning signs and act quickly. Face drooping indicates facial weakness on one side; have the person smile and look for asymmetry. Arm weakness means trouble raising both arms or one arm drifting downward when held straight ahead. Speech difficulty involves slurred speech, trouble speaking, or confusion; ask simple questions and listen for clarity. Time to call emergency services emphasizes urgent action, because swift medical treatment within a narrow window can reduce brain damage. These components together help identify a possible stroke fast, prompting immediate EMS activation, as opposed to signs like fever or temperature that are not stroke indicators.

Treating an acute ischemic stroke with IV tPA is highly time-dependent. The accepted therapeutic window for giving IV alteplase in eligible patients is within 4.5 hours from when symptoms began. Treating within this period maximizes the chance of dissolving the clot before irreversible brain damage occurs, helping to preserve function. Trials showed strong benefit early on, and an extended window to 4.5 hours is allowed for carefully selected patients who meet specific criteria and have no contraindications, with imaging used to rule out hemorrhage. Beyond 4.5 hours, the risk of symptomatic intracranial hemorrhage rises and the potential benefit declines, so IV tPA is generally not given in that later window.