Hemiparesis Caused by Cerebral Venous Sinus Thrombosis during the Postpartum Period: A Case Report; Negelle Arsi General Hospital and Medical College, Ethiopia

Introduction

Cerebral venous thrombosis (CVT), which involves the clotting of veins and sinuses within the brain, is an uncommon form of cerebrovascular disorder. It primarily impacts young women, affecting around five individuals per million and representing only 0.5% of all strokes.^1–3 The annual incidence of CVT falls between 0.22 and 1.57 cases per 100,000 individuals in the broader population.^4–7

Risk factors for CVT include conditions that lead to increased blood clotting, such as inherited prothrombotic disorders, autoimmune diseases, the use of oral contraceptives or hormonal replacement therapy, pregnancy or the postpartum period, cancer, infections, or chronic inflammatory conditions.³ CVT is more commonly observed in female patients, likely due to the presence of gender-specific risk factors for clotting disorders, such as pregnancy and the use of oral contraceptives.⁸

The pathophysiology of CVT results from a complex interplay among genetic predisposition, hypercoagulable conditions, venous stasis, endothelial damage, changes in blood composition, and inflammatory responses. These factors collectively contribute to the formation of blood clots within the brain’s veins. CVT can stem from systemic or localized disruptions in prothrombotic and thrombolytic functions, leading to the development and dissemination of blood clots within the cerebral dural sinuses or veins. Consequently, venous blood is redirected into narrower vessels and capillaries, causing increased pressure within the venous and capillary systems.^1,2,4,9

CVT can manifest with a diverse range of symptoms and onset patterns, often resembling various other conditions, which poses a diagnostic challenge for clinicians. Headache, seizures, focal neurological deficits, altered consciousness, and papilledema are among the most frequently observed symptoms and signs. These symptoms may occur individually or in combination with others.^1,8,10–12

Several conditions can mimic the symptoms of CVT, highlighting the critical need for precise diagnosis. These conditions include migraine headaches, ischemic stroke, subarachnoid hemorrhage, infections such as meningitis or encephalitis, space-occupying lesions like intracranial tumors, posterior reversible encephalopathy syndrome, and idiopathic intracranial hypertension.^1,3,13,14

Diagnosing CVT poses challenges; nevertheless, the Introduction of magnetic resonance imaging (MRI) has improved diagnostic capabilities,¹⁵ magnetic resonance venography (MRV), computed tomography venography (CTV), and magnetic resonance angiography(MRA) are imaging methods utilized to verify the existence and pinpoint the location of thrombosed sinuses in CVT. As such, these imaging techniques play a crucial role in confirming the diagnosis of the condition.⁸

The long-term prognosis CVT depends on factors like clot severity, promptness of diagnosis and treatment, and patient health. Mortality rates, ranging from 4% to 15%, are affected by age, existing conditions, and intracranial bleeding. Recurrence is rare but possible, especially in those with prothrombotic conditions.^1,2,4

Timely diagnosis and treatment are crucial as they can potentially save a patient’s life and prevent long-term disabilities. In this case study, we illustrate the significance of early detection and appropriate intervention by presenting a patient who initially presented with symptoms of hemiparesis, seizures, and papilledema, which were initially misattributed to migraine headaches. These complications were later identified as consequences of CVT, underscoring the importance of timely diagnosis and therapeutic measures in managing the condition.

Case Presentation

This case involves a 29-year-old mother who has given birth four times, currently in her second month postpartum, presenting to the emergency department with complaints of headaches and blurred vision persisting for three weeks. She also reported experiencing right-sided body weakness for one day. Despite being treated twice before for migraine headaches, a diagnosis of CVT was eventually made. There is no personal or family history of thromboembolism. Upon examination, her blood pressure was 100/60 mmHg, and all other vital signs were within normal limits. She was fully conscious, with a Glasgow Coma Scale (GCS) score of 15/15. Motor strength was 4/5 in the right upper extremity, 4+ in the right lower extremity, and 5/5 in the left upper and lower extremities. Meningeal signs were absent. Laboratory tests including complete blood count, random blood sugar, organ function tests, and viral markers were all normal. A contrast-enhanced head computed tomography (CT) scan revealed a filling defect along the superior sagittal sinus, resembling a delta sign, as well as a tubular filling defect along the posterior aspect of the superior sagittal sinus (Figure 1a and b). Enoxaparin treatment was started, and the patient was admitted to the medical ward. On the admission day, the patient experienced a single episode of generalized tonic-clonic seizure and was subsequently moved to the intensive care unit, where phenytoin was initiated. Magnetic resonance imaging (MRI) with MRV conducted on the second day of admission revealed a focal filling defect in the right anastomotic vein and the posterior segment of the superior sagittal sinus (Figure 2a–g). The patient underwent an ophthalmologic assessment, which revealed a diagnosis of papilledema. Treatment with acetazolamide was initiated accordingly. She remained in the intensive care unit for 5 days and subsequently spent 11 days in the medical ward. After a total of 16 days of hospitalization, the patient’s condition improved with the combination of phenytoin, acetazolamide, and warfarin. Considering the postpartum period as a temporary risk factor for CVT, oral anticoagulation and other medications were ceased after six months of treatment. The patient is presently in good health, indicating an absence of weakness, headaches, or any lingering symptoms previously experienced.

Figure 1 (a) Coronal contrast-enhanced CT scan of the brain reveals a filling defect along the superior sagittal sinus, presenting as a delta sign (indicated by an arrow). (b) Sagittal contrast-enhanced CT scan of the brain displays a tubular filling defect along the posterior aspect of the superior sagittal sinus (highlighted by an arrow).

Figure 2 (a) Axial T1WI-SE brain MRI shows slightly high signal intensity of superior sagittal sinus posteriorly (arrow) compared to cerebral white matter. (b) and (c) Axial T2-weighted and Diffusion-weighted Imaging (DWI) Brain MRI depicting high signal intensity along the posterior aspect of the superior sagittal sinus (indicated by arrows) respectively. (d) and (e) Sagittal T2-weighted spin echo (T2WI- SE) and coronal T1-weighted spin echo (T1WI-SE) brain MRI demonstrating hyperintensity along the posterior aspect of the superior sagittal sinus and the right vein of Trolard (superior anastomotic vein) respectively. (f) and (g) The MRV reveals a focal absence of blood flow (filling defect) along the posterior portion of the superior sagittal sinus and the right vein of Trolard (superior anastomotic vein).

Discussion

Cerebral venous thrombosis (CVT) is a relatively rare and frequently misdiagnosed condition, impacting about five individuals per million and making up roughly 0.5% of all stroke cases.^1,2

Typical risk factors for CVT encompass acquired hypercoagulability, hereditary thrombophilia, and conditions leading to increased blood viscosity, such as hyperhomocysteinemia, antiphospholipid antibody syndrome, Behcet’s disease, and various hematological disorders.³ In female patients, the primary risk factors for CVT include pregnancy/postpartum, oral contraceptive use, and the utilization of fertility drugs.^3,11,15

The diagnosis of CVT presents challenges due to its infrequency and diverse clinical manifestations, often leading to confusion with other typical postpartum issues. A delayed diagnosis is linked with substantial morbidity and mortality.¹ Headache is the predominant symptom of CVT, observed in over 80% of cases.^1,15–17 Other symptoms include focal neurological deficits, papilledema, visual impairments, and seizures followed by postictal confusion.^8,18

If there is suspicion of CVT, immediate imaging modalities, particularly MRV or CTV, should be conducted. The transverse sinus is the most frequent site of thrombosis formation, followed by the sigmoid sinus.^15,19,20

Anticoagulation, primarily with low molecular weight heparin (LMWH) instead of unfractionated heparin (UFH), is the primary treatment approach recommended for acute CVT. This is typically followed by oral anticoagulation therapy.²⁰

In this report, we highlight a case that has frequently been misdiagnosed or overlooked as evidenced by - limited available case reports or studies in Africa, specifically in Ethiopia.

Conclusion

We present an uncommon instance of CVT accompanied by hemiparesis and seizures in a patient during the postpartum phase, initially mistaken for a migraine headache. This underscores the importance of considering a wide range of possibilities in the differential diagnosis of headache in postpartum patients. Early detection and treatment are crucial in averting complications and mortality.