A Study On Clinical Features And Prognostic Factors Of Cerebral Venous Thrombosis

ObjectivesTo summarize the etiology, clinical feature and prognosis of CVT and investigate the related factors' impacts on the prognosis of CVT. Material and methods1. The general picture of 136 consecutive patients with CVT admitted to PLA General Hospital between January 1986 and December 2005 was described.2. The clinical features of 91 CVT patients without identified causes were analyzed in comparison with those with known causes by univariate analysis.3. The site and the number of thrombosed sinuses of 136 patients with CVT were summarized. The clinical features and outcome of the patients with single CVT were analyzed in comparison with those with multiple CVT by univariate analysis.4. The short-term prognosis of 136 patients with CVT was summarized. The related factors' influences on short-term prognosis were studied by logistic regression analysis.5. The long-term prognosis of 43 patients with CVT who had been followed up for more than 3 years was summarized. The related factors' influences on long-term prognosis were studied by logistic regression analysis.6. The etiologies , clinical features, neuroimaging data ,treatment and the causes of death of 5 CVT patients who had died were summarized retrospectively. The univariate analysis was employed to find predictors of death in CVT patients.Results1. The study population consisted of 136 patients(69 men and 67 women),with a mean age of 34.85 ± 9.56 years(10～63 years).The mode of onset was acute in 65 ( 47.8% ) patients, subacute in 54 ( 39.7% ), and chronic in 17 (12.5%) .The median delay from onset of symptoms to diagnosis was 83 days. Anemia(8.1 % ) , pregnancy and the puerperium(7.4%) , use of oral contraceptives(5.9%) were the most common causes. No causes were found in 91 patients(66.9%) . 97 patients(71.3%) presented isolated intracranial hypertention, and 39 patients(28.7%) presented other syndromes. In 92 patients(67.6%) ,more than one sinus was involved. The lateral sinus was the most frequent thrombosed sinus. In 39 patients(28.7 %) , cerebral edema,cerebral infarction and intracranial hemorrhage were revealed. The mean intracranial pressure was 341.21 ±79.38mmH₂O(210～700mmH₂O),and intracranial pressure was ≥400mmH₂O in 42 patients(30.9%). In the acute phase, 109 patients (80.1% ) were treated with thrombolysis followed by anticoagulant therapy, 10 (7.4%) were treated only with thrombolysis , and 9(6.6% )were anticoagulated alone. 22 patients(16.2 %) were treated with interventional therapy and only 4 patients (2.9%) underwent decompressive craniotomy or hemotoma evacuation. At discharge,45 patients(33.1%) had complete recovery, 62(45.6%) had partial recovery and 29(21.3%) had no improvement .2 patients (1.5%) died.2. Probable causes were found in 45(33.1%) patients , and the proportion of CVT patients without identified causes was 66.9%. Univariate analysis showed that the proportion of male was significantly higher in patients without identified causes compared with those with known causes.Isolated intracranial hypertension syndrom was more frequent in patients without identified causes whereas serious intracranialhypertension(≥ 400mmH₂O) was less frequent . The cure rate was higher in patients without identified causes.3. In 44 patients(32.4%),only one cerebral sinus was involved.In 92(67.6%) patients two or more cerebral veins and sinus were involved(2 sinuses in 45 patients, 3 sinuses in 35 patients, 4 sinuses in 9 patients, 5 sinuses in 3 patients). The lateral sinus was the most frequent thrombosed sinus which was found in 86.8% of patients .The followings were superior sagittal sinus (58.1%), straight sinus (18.4%) , deep venous system (7.4%), the inferior sagittal sinus (3.7%), and cortical veins(2.9%). Mean age was significantly higher but the short-term prognosis was better in the group of patients with single CVT in comparsion with the group of patients with multiple CVT. The patients with multiple CVT also presented more serious intracranial hypertension , more frequent parenchymal lesions and systematic thrombotic events.4. In the 136 patients with CVT, 45 patients(33.1%) had complete recovery, 62(45.6%) had partial recovery and 29(21.3%) had no improvement, 2 patients (1.5%) died in the acute phase. When the short-term prognosis of patients with CVT was dichotomized as "good"(107, 78.3 % )and "poor"(29, 21.3%) according to intracranial pressure and presenting syndromes, the univariate analysis identified factors associated with poor outcome were parenchymal lesions , multiple CVT , serious intracranial hypertension(≥ 400mmH₂O), and thrombosis of the bilateral transverse sinuses or the sraight sinus ,and there was a tendency towards poor outcome in patients with mental disturbance or thrombosis of deep cerebral venous system. In the logistic regression analysis,mental disturbance ,coma, serious intracranial hypertension(≥ 400mmH₂O) and thrombosis of the sraight sinus were identified as adverse prognostic factors while thrombosis of single sinus and thrombolytic treatment followed by anticoagulant treatment as independent favorableprognostic factors5. 43 patients with CVT were followed up for average of 66 months. During the following up, four patients(9.3%) died, three (7.0%) developed blindness, one(2.3%) developed seizures and one(2.3%) developed aphasia and mental disturbance. Thirty-four patients(79.1%) had complete recovery. In the 42 patients who survived the acute phase, seven patients(16.7%) had a recurrent sinus thrombosis. The univariate analysis identified factors associated with unfavorable long-term outcome were aphasia and sensory symptoms. Paresis, intracranial hemorrhage, multiple CVT and thrombosis of the superior sagittal or deep cerebral venous system were also weakly,but not significantly associated with unfavorable long-term outcome. Logistic regression analysis revealed that intracranial hemorrhage on admission was indepent predictor of unfavorable outcome and long-term anticoagulant treatment (> three months) was an independent predictor of favorable outcome.6. Among the five patients who died , two patients died in the acute phase and the other three died in the chronic phase.The direct cause of death was cerebral transtentorial herniation caused by multiple intracranial hemorrhagic lesions and multiple cerebral venous thrombosis.We found no association between mortality and sex, age, length of time between onset of symptoms and diagnosis , epileptic seizures , location of the thrombus and intracranial pressure before treatment. Some symptoms such as aphasia, paresis, mental disturbance and coma increased the risk of death significantly,which were caused by multiple intracranial hemorrhage and multiple cerebral venous thrombosis.Conclusions1. CVT was a rare disease with variety of causes and onset modes, and most occurred in young people. Increased intracranial pressure was the most common clinical manifestation. In the acute phase, 109 patients(80.1% ) were treated with loca thrombolysis followed by anticoagulant therapy. At discharge,107 patients(78.7%) improved clinically,and 2 patients (1.5%) died.2. The proportion of male was significantly higher and isolated intracranial hypertension syndrom was more frequent in patients without identified causes in comparsion with those with known causes . The intracranial hypertension was less serious and the cure rate was higher in patients without identified causes.3. In most CVT patients ,two or more veins and sinuses were invovled. Thrombosis most common imlicated the lateral sinus and the superior sagittal sinus. Patients with multiple CVT usually presented higher intracranial pressure ,more serious clinical course, worse outcome and the higher incidence of systematic venous thrombotic events in comparsion with patients with single CVT. And the multiple sinus thrombosis was more likely to cause venous infarctions and intracranial hemorrhage than the single one.4. The outcome of CVT patients in our study was fairly good at discharge. 78.7% of patients had complete or partial recovery. Mortality at the acute stage was 1.5%. Independent predictors of poor outcome were mental disturbance, coma, serious intracranial hypertension( ≥ 400mmH₂O) and thrombosis of the sraight sinus while significant predictors of good outcome were thrombosis of single sinus and thrombolytic treatment followed by anticoagulant treatment.5. The long-term prognosis of CVT patients was fairly good. 79.1% of the patients had complete recovery. However, 16.7% of the patients had a recurrent sinus thrombosis. Intracranial hemorrhage was the independent predictor of unfavorable outcome while long-term anticoagulant treatment (> three months) was the predictor of favorable outcome.6. The direct cause of death in CVT was cerebral transtentorial herniationcaused by multiple intracranial hemorrhagic lesions and multiple thrombosed cerebral veins and smuses. Death could occur not only in the acute phase but also in the chronic phase of CVT.