Pseudo-subarachnoid hemorrhage in cerebellar infarction

Area of Science:

• Neurology
• Radiology
• Neuroimaging

Background:

• Subarachnoid hemorrhage (SAH) is a critical condition often diagnosed via CT scans.
• Pseudo-SAH describes CT findings suggestive of SAH but without actual subarachnoid blood.
• Pseudo-SAH has been linked to various conditions like meningitis, cerebral edema, and intracranial hypotension.

Observation:

• A 43-year-old female presented with acute vertigo and severe headache.
• Initial CT brain suggested SAH with hydrocephalus.
• Cerebral angiography and cerebrospinal fluid analysis were negative for SAH.

Findings:

• MRI brain revealed an acute stroke in the posterior inferior cerebellar artery (PICA) territory.
• This PICA infarction was associated with CT findings mimicking SAH (pseudo-SAH).

Implications:

• PICA infarction is identified as a potential cause of pseudo-SAH.
• This finding broadens the differential diagnosis for pseudo-SAH.
• Highlights the importance of advanced neuroimaging like MRI to differentiate stroke from SAH in ambiguous CT presentations.