Seizures as the initial presentation of cerebral venous sinus thrombosis in an elderly patient: a case report and literature review.

Introduction and importance: Cerebral venous sinus thrombosis (CVST) is a rare cerebrovascular disorder with heterogeneous clinical presentations. Although headache is the most common symptom, atypical presentations without headache may lead to diagnostic challenges, particularly in elderly patients. Seizures are a recognized manifestation of CVST but are occasionally the sole initial presentation. Case presentation: We describe a 64-year-old man with recurrent seizures and transient right-sided weakness, without headache. Brain magnetic resonance imaging revealed left frontal encephalomalacia, which initially complicated the diagnostic evaluation. Markedly elevated D-dimer levels and bilateral calf vein thrombosis were identified, while subsequent multimodal imaging, including computed tomography venography, demonstrated superior sagittal sinus thrombosis with prominent collateral venous channels. The seizures were considered to be related to a combined mechanism, in which the pre-existing encephalomalacic lesion may have increased seizure susceptibility, and CVST may have acted as a precipitating factor. Anticoagulation therapy and appropriate antiseizure treatment led to seizure resolution and clinical improvement. Clinical discussion: This case highlights a diagnostic pitfall in which competing but plausible findings may delay recognition of CVST. In elderly patients with atypical presentations, reliance on a single explanatory finding may contribute to premature diagnostic closure. Persistent or unexplained neurological symptoms should prompt reconsideration and further vascular imaging. Conclusion: CVST should be considered in patients with unexplained seizures, even in the absence of a headache. Early recognition and timely anticoagulation are essential to improve outcomes.