A deceptive presentation: Cerebral venous thrombosis masking spontaneous intracranial hypotension

Spontaneous intracranial hypotension (SIH) can usually present with headache and a group of specific imaging findings that include diffuse pachymeningeal enhancement, subdural effusions, and cerebellar tonsil herniation, and due to the Monro–Kellie hypothesis, there is compensatory venous engorgement which can manifest as cerebral venous thrombosis (CVT). We report a case of a 29-year-old female who presented with a progressively worsening headache, and the initial non-contrast computed tomography scan suggested a possible diagnosis of CVT with chronic subdural hematoma and hemorrhagic infarct. However, in the absence of any definite clinical explanation of CVT by patient history, a magnetic resonance imaging (MRI) of the brain with MR venogram was performed that revealed the absence of blooming artifacts on susceptibility-weighted imaging within the previously suspected chronic subdural hematoma, due to which it was then considered subdural effusions. To characterize the subdural collection and rule out any infective or inflammatory etiology, a contrast MRI was performed which revealed diffuse pachymeningeal enhancement. This led to the final diagnosis of SIH which manifested as CVT. This case highlights the importance of clinico-radiological correlation and the superiority of MRI to differentiate between various types of subdural fluid collections, which helped in avoid misdiagnosing the condition, and also recognizes CVT as a rare but crucial complication of SIH.