Differential Diagnosis for Hemiplegia Post Stroke with Falls and Head Injury

Single Most Likely Diagnosis

• Post-stroke sequelae with new subdural hemorrhage: The patient has a history of stroke with significant left cerebral hemisphere damage, and the current CT scan shows a new trace acute right posterior parafalcine subdural hemorrhage. This, combined with the patient's history of falls, makes it likely that the subdural hemorrhage is related to the falls, exacerbating the patient's condition.

Other Likely Diagnoses

• Chronic small vessel ischemic changes: The CT scan shows scattered nonspecific hypodensities in the cerebral white matter, which are compatible with mild chronic small vessel ischemic changes. These changes could contribute to the patient's hemiplegia and overall neurological status.
• Complications of cerebral atrophy: Moderate cerebral atrophy is noted on the CT scan, which could be contributing to the patient's balance issues and increased risk of falls.
• Right swollen foot due to immobility or venous insufficiency: The patient's right swollen foot could be due to immobility or venous insufficiency secondary to the hemiplegia, rather than a new or separate condition.

Do Not Miss Diagnoses

• Intracranial hemorrhage expansion or worsening: Although the current subdural hemorrhage is small, there is a risk of expansion or worsening, which could lead to increased intracranial pressure, mass effect, and potentially life-threatening complications.
• Infection (e.g., sinusitis): The moderate mucosal thickening in the right maxillary sinus could be indicative of an infection, which, if left untreated, could lead to more severe complications, including intracranial spread of infection.
• Deep vein thrombosis (DVT): The patient's right swollen foot could be a sign of DVT, which is a potentially life-threatening condition if not promptly diagnosed and treated.

Rare Diagnoses

• Cerebral amyloid angiopathy: Although less likely, the presence of lobar hemorrhages or microbleeds could suggest cerebral amyloid angiopathy, especially in the context of the patient's age and history of stroke.
• Vasculitis or other inflammatory conditions: Rarely, conditions like vasculitis or other inflammatory diseases could present with similar imaging findings and clinical symptoms, although these would be less likely given the patient's history and presentation.