A Rare Case of Cerebral Venous Sinus Thrombosis in the First Trimester of Pregnancy

Abstract

Background: Cerebral venous sinus thrombosis (CVST) is a rare but serious neurovascular emergency with a higher incidence in young women, particularly during pregnancy and the puerperium, and with markedly higher rates reported in developing countries such as India due to preventable obstetric and lifestyle-related risk factors. Aims: The aim of this study is to heighten clinical suspicion and promote timely neuroimaging in pregnant patients presenting with persistent headache or neurological deficits. Presentation of Case: A 34-year-old gravida 2 para 1 woman presented at 8 weeks’ gestation with right-sided headache and left-sided hemiparesis for 5 days, with one episode of seizure-like activity at home. On admission, her Glasgow Coma Scale score was 15/15, vital signs were normal, and no focal neurological deficit was identified on examination. Non-contrast computed tomography of the head showed a hyperdense posterior superior sagittal sinus and great cerebral vein, raising concern for venous sinus thrombosis. Computed tomography venography confirmed dural venous sinus thrombosis. She was managed by obstetrics and neurology and was treated with dalteparin and seizure prophylaxis while continuing the pregnancy. Follow-up computed tomography venography at 6 months demonstrated complete recanalisation of the superior sagittal sinus. A multidisciplinary plan was made for delivery at 36–37 weeks, with transition to unfractionated heparin before labour. Labour was induced at 37+1 weeks, and she delivered a healthy baby vaginally with an estimated blood loss of 100 cc. She subsequently made a full recovery. Conclusion: Cerebral venous sinus thrombosis (CVST) should be considered in pregnant patients presenting with acute neurological symptoms, even during the first trimester, despite its greater association with the third trimester and puerperium. The “dense sinus sign” on non-contrast CT of the head may provide an important early imaging clue, while CT venography remains a sensitive and readily available method for confirming the diagnosis.