Isolated Vein Thrombosis of the Posterior Fossa Presenting as Localized Cerebellar Venous Infarctions or Hemorrhages

Abstract

Background and Purpose-Cerebellar venous infarction or hemorrhage due to isolated venous thrombosis of the posterior fossa is a rare form of intracranial vein thrombosis that can be unsuspected in clinical practice. Methods-We studied 230 patients with intracranial vein thrombosis, identifying 9 (3.9%: 7 women, mean age 34 years) with neuroimaging or histopathologic evidence of localized posterior fossa vein thrombosis causing parenchymal injury limited exclusively to the cerebellum. Results-All patients had an insidious presentation suggesting other diagnoses. Intracranial hypertension (nϭ6) and cerebellar (nϭ4) syndromes were the main clinical presentations. Intracranial vein thrombosis was idiopathic in 3 patients; associated with puerperium in 3; and with contraceptives, protein C deficiency, and dehydration in 1 case each. CT was abnormal but not diagnostic in 5 patients, showing a cerebellar hypodensity with fourth ventricle compression and variable hydrocephalus in 5 patients, and cerebellar hemorrhage in 2. Conventional MRI provided diagnosis in 6 cases, showing the causal thrombosis and cerebellar involvement; angiography was practiced in 2 of them, confirming the findings identified by MRI. In the other 3 patients, diagnosis was reached by histopathology. Thromboses were localized at the straight sinus (nϭ4), lateral sinuses (nϭ3), and superior petrosal vein (nϭ2). The acute case fatality rate was 22.2% (nϭ2), 1 (11.1%) patient was discharged in a vegetative state, 1 (11.1%) was severely disabled, and 5 (55.6%) were moderately disabled. Conclusions-Isolated

Cerebral Venous Thrombosis in a Mexican Multicenter Registry of Acute Cerebrovascular Disease: The RENAMEVASC Study

“…6,[8][9][10] In Mexico, information regarding CVT has mainly derived from single-center reports, with a relative frequency among all forms of acute cerebrovascular disease ranging from 0.43% to 8%. [11][12][13] There is a paucity of international epidemiologic data on incidence, prevalence, or relative frequency among hospitalized stroke patients, and hospital registers on all-type acute stroke cases rarely refer specifically to CVT. 14,15 The National Mexican Registry of Cerebral Vascular Disease (RENAMEVASC) was a multicenter stroke surveillance system that included 2000 consecutive patients with all types of acute cerebrovascular disease, 16,17 of whom 59 were identified with CVT.…”

MRI of Cerebellar Infarction

“…Common risk factors for venous sinus thrombosis include puerperium, oral contraceptives, protein C of factor V Leiden deficiency and dehydration [28,29,30]. …”

“…Cerebellar venous infarction usually results from thrombosis of the straight sinus, lateral sinuses or superior petrosal vein [28,29]. MRI can show the causal thrombosis as well as the parenchymal abnormalities.…”

“…Also there is a tendency for haemorrhagic alterations that may be visible on T2* or susceptibility-weighted imaging (SWI) images [44]. Although venous clot may be visible directly on T1WI or T2WI as absent flow voids or on DWI as a zone of restricted diffusion in the vessel lumen, contrast-enhanced MRI with the inclusion of MR venography is the imaging study of choice for diagnosing sinus thrombosis [28,30]. If unenhanced MRI alone is used, thrombus in the early stage of evolution may mimic normal flow [29].…”

Cerebral Venous Thrombosis Causing Posterior Fossa Lesions: Description of a Case Series and Assessment of Safety of Anticoagulation

“…The clinical features and outcome of patients with CVT and posterior fossa lesions have been addressed only in two previous small series, with nine and six patients, respectively [3,4] and case reports [5,6,7,8,9,10,11,12,13,14,15,16,17], which all together account for less than 30 patients.…”