Thrombosis in a congenitally bifurcated superior sagittal sinus.

Abstract

A 26-year-old woman had a peripartum venous thrombotic stroke involving the right parietal lobe. The initial thrombus was present only in the right channel of a congenitally bifurcated superior sagittal sinus. This diagnosis and subsequent thrombus extension were readily shown by magnetic resonance imaging in contrast to equivocal angiography. A subsequent, prospective review of 100 patients undergoing cranial magnetic resonance imaging showed the presence of similarly bifurcated superior sagittal sinuses in two. The patient stabilized after therapy with intravenous heparin, but switching her medication to oral warfarin sodium was followed by clinical deterioration and propagation of the thrombus, necessitating resumption of intravenous heparin. No coagulopathy was identified. (Stroke 1991^2:396-400) M aternal stroke during the peripartum period caused by venous thrombosis has an estimated incidence of between one in 2,500 births at tertiary care centers and one in 10,000 births in the population at large.1 Of the strokes diagnosed during pregnancy and the puerperium, 86% are venous when the onset is 1-5 weeks postpartum, while 83% are arterial when the onset is during the last trimester and first week postpartum.2 Stroke patients with venous thrombosis often have focal neurological signs referable to the area of infarction, severe headaches, and seizures. -2 Mortality is high, up to 25%. 3 Prompt diagnosis is important, and cerebral angiography is the diagnostic procedure most widely recommended. 4 -6 Alternative studies including contrast-enhanced cranial computed tomography (CT) of the head, digital subtraction angiography, nuclear scintigraphy of thrombus formation, and, more recently, magnetic resonance imaging (MRI) have been suggested.We report a patient with a postpartum venous thrombosis of a congenitalry bifurcated superior sagittal sinus in whom angiography was inconclusive while MRI studies were diagnostic.Case Report A 26-year-old woman with a history significant only for migraine headaches had had two previous normal deliveries. She gave birth to a term infant by cesarean section and then developed a diffuse throb- Received July 31, 1990; accepted October 22, 1990. bing headache during postpartum day 2. On postpartum day 6, the patient awoke with a severe rightsided pressure headache and with slight left-sided weakness. The headache persisted despite narcotic analgesics, and her left hemiparesis progressed in severity. An initial head CT scan revealed an area of hypodensity in the right parieto-occipital area consistent with an infarct. Later that day, neurological examination showed a left facial droop, a moderate left hemiparesis, and a left homonymous hemianopsia. A repeat enhanced head CT scan showed the infarct but no evidence of hemorrhage or abnormal vasculature. The cerebrospinal fluid contained 160 erythrocytes/ml, 0 leukocytes/ml, 55 mg/dl glucose (serum glucose concentration was 105 mg/dl), and 139 mg/dl protein. On hospital day 2 (postpartum day 8), an arch aortogram and a selecti...