Differential Diagnosis

• Single most likely diagnosis
  • Subdural hematoma: Given the patient's age, use of warfarin, and history of a fall, a subdural hematoma is highly likely. The patient's presentation with disorientation and anisocoria (unequal pupil sizes) after a delay suggests increased intracranial pressure, which is consistent with a subdural hematoma.
• Other Likely diagnoses
  • Epidural hematoma: Although less common in the elderly, an epidural hematoma is still a possibility, especially given the patient's use of warfarin and the mechanism of injury. However, epidural hematomas typically present more acutely.
  • Intracerebral hemorrhage: The patient's use of warfarin increases the risk of intracerebral hemorrhage, and the presentation with disorientation could be consistent with this diagnosis. However, the history of a fall and the presence of anisocoria might lean more towards a subdural hematoma.
• Do Not Miss diagnoses
  • Subarachnoid hemorrhage: Although less likely given the mechanism of injury, a subarachnoid hemorrhage could present with sudden onset of symptoms, including disorientation and anisocoria. Missing this diagnosis could be catastrophic.
  • Cervical spine injury: Given the patient's age and the mechanism of injury, a cervical spine injury is possible and could have serious consequences if missed.
• Rare diagnoses
  • Arteriovenous malformation (AVM) rupture: Although rare, an AVM rupture could present with sudden onset of symptoms, including disorientation and anisocoria. However, this would be less likely given the patient's age and the history of a fall.
  • Brain tumor: A brain tumor could present with disorientation and anisocoria, but this would be less likely given the acute presentation and the history of a fall.