Intracranial hypotension as a contributor to isolated cortical vein thrombosis

Background: Isolated cortical vein thrombosis (ICVT), a rare type of cerebral venous thrombosis (CVT), is diagnostically challenging in some cases, and intracranial hypotension (IH) is known to cause CVT.

Methods: In this study, we reviewed the clinical and imaging characteristics of ICVT in patients with IH caused by spinal cerebrospinal fluid leakage, based on a literature review and investigation of cases from our hospital.

Results: Between January 1, 2007, and November 1, 2019, 735 patients were diagnosed with IH at our hospital; three patients developed ICVT (incidence ~ 0.4%, 3/735), and the literature review yielded an additional 23 cases. Therefore, 26 patients (mean age 35.9 ± 11.4 years old) were included in this study. The most common symptoms were headache (100.0%, 26/26), focal neurological deficits (53.8%, 14/26), and seizure (34.6%, 9/26). The initial headache was orthostatic in 96.2% (25/26) of patients, and 38.5% (10/26) of patients reported a change in the headache pattern following diagnosis of ICVT. Neuroimaging findings associated with ICVT included the cord sign (61.5%, 16/26) and parenchymal brain lesions (46.2%, 12/26), such as intracerebral hemorrhage (30.8%, 8/26), hemorrhagic infarcts (11.5%, 3/26), and localized edema (11.5%, 3/26). The percentage of patients who received anticoagulation and epidural blood patch therapy was similar (69.2% [18/26] vs. 65.4% [17/26]), and most patients recovered completely (92.3%, 24/26).

Conclusion: IH should be considered in the differential diagnosis in patients with ICVT. Knowledge of the relevant clinical and neuroimaging features is important to facilitate early diagnosis for favorable prognosis.