Differential Diagnosis for the Presented Case

The patient's history and symptoms suggest a neurological condition related to the fall. Given the information, here's a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • B. Chronic Subdural Hematoma: This is the most likely diagnosis given the patient's age, history of a recent fall, and the presence of two hypodense brain lesions on the CT image. The fact that the patient was able to walk and had no immediate severe symptoms after the fall but later developed weakness and inability to stand or walk suggests a gradual increase in intracranial pressure, which is consistent with a chronic subdural hematoma. The time frame of two weeks after the fall also supports this diagnosis, as chronic subdural hematomas can present with delayed symptoms.

• Other Likely Diagnoses

  • D. Subacute Subdural Hematoma: This could be considered if the symptoms and CT findings are not entirely typical for a chronic subdural hematoma. The subacute phase is a transition period between acute and chronic, and the presentation can vary. However, the lack of immediate severe symptoms post-fall and the delayed onset of significant weakness make this less likely than a chronic subdural hematoma.
  • A. Acute Subdural Hematoma: Although less likely given the delayed presentation, an acute subdural hematoma could be considered if there were any signs of increased intracranial pressure or focal neurological deficits immediately after the fall that were missed or not reported. However, the patient's ability to walk after the fall and the absence of severe headache or loss of consciousness make this less probable.

• Do Not Miss Diagnoses

  • C. Extradural Hemorrhage: Although extradural (epidural) hemorrhages are typically associated with more immediate and severe symptoms after a head injury, including loss of consciousness and severe headache, they can occasionally present atypically, especially in the elderly or those on anticoagulation. Given the potential for rapid deterioration, it's crucial not to miss this diagnosis, despite its lower likelihood in this scenario.
  • Other Intracranial Pathologies: Conditions such as intracerebral hemorrhage, cerebral infarction, or even brain tumors could potentially present with similar symptoms and should be considered, especially if the CT findings are not typical for a subdural hematoma or if there are other clinical indicators.

• Rare Diagnoses

  • Traumatic Subarachnoid Hemorrhage: While possible, this would typically present with more immediate and severe symptoms, including severe headache (often described as "the worst headache of my life") and possibly loss of consciousness.
  • Cerebral Vasculitis or Other Vascular Pathologies: These conditions could potentially cause similar symptoms but would be less directly related to the fall and more related to the patient's overall vascular health or the presence of an underlying autoimmune condition.