NURS 6501: Final Exam: Please contact Assignment Samurai for help with NURS 6501: Final Exam or any other assignment. Email: assignmentsamurai@gmail.com   What is the key feature that differentiates a transient ischemic attack (TIA) from a stroke? Group of answer choices

• TIAs involve permanent brain injury.
• TIAs usually last more than one hour.
• TIAs are caused by bleeding in the brain.
• TIAs usually resolve within a short period without infarction.

  The correct answer is: TIAs usually resolve within a short period without infarction.   Explanation: The key distinction between a transient ischemic attack (TIA) and a stroke is the absence of permanent brain damage (infarction) in TIA:

• TIA:
  • Neurologic deficits resolve completely (typically within <1 hour, though by definition <24 hours).
  • No acute infarction on imaging (diffusion-weighted MRI is the gold standard to rule out small infarcts).
• Stroke:
  • Permanent infarction occurs (visible on imaging).
  • Symptoms persist beyond 24 hours (though most strokes are evident much sooner).

Why Not the Others?

• "TIAs involve permanent brain injury": False—this defines a stroke, not a TIA.
• "TIAs usually last >1 hour": False—most resolve within 60 minutes (though the formal cutoff is 24h).
• "TIAs are caused by bleeding": False—TIAs are ischemic (due to temporary clot/hypoperfusion); bleeding causes hemorrhagic stroke.

Clinical Implications:

• TIA is a medical emergency—10-15% risk of stroke within 90 days (highest in first 48h).
• ABCD2 score helps stratify risk and guide urgent evaluation (e.g., carotid imaging, anticoagulation for AF).

Thus, the transient nature without infarction is the defining feature of TIA.