Diagnosis of cerebral venous thrombosis with echo-planar T2*-weighted magnetic resonance imaging

BACKGROUND: Magnetic resonance (MR) signal changes suggestive of cerebral venous thrombosis (CVT) on T1- and T2-weighted images may be subtle and their identification requires a high degree of suspicion. Magnetic resonance venography remains essential for definitive diagnosis. Recent reports have shown that T2(*)-weighted MR sequence is more sensitive than T1-weighted, T2-weighted, and fluid-attenuated inversion recovery (FLAIR) images in detecting subarachnoid and intracerebral hemorrhages, both of which can be seen in association with CVT. The value of T2*-weighted magnetic resonance imaging (MRI) in diagnosing CVT has not been well studied. OBJECTIVES: To investigate and describe T2*(susceptibility-weighted) MRI findings in 5 patients with CVT. METHODS: We reviewed our stroke database from May 1, 1997, through May 31, 2001. The diagnosis of CVT was made in 6 patients, 5 had an MRI with T2* sequence. We examined T2*/susceptibility-weighted images for these 5 patients to determine their ability, relative to T1-weighted, T2-weighted, and FLAIR sequences, to detect CVT. RESULTS: On T2*-weighted images, we were able to detect areas of hypointensities in the affected veins and/or sinuses in all 5 patients. Thrombosed veins and/or sinuses were more easily seen on T2*-weighted images than on any other MR sequence. The T2* sequence also allowed visualization of associated hemorrhagic venous infarcts, which were considerably less obvious on other MR sequences. CONCLUSIONS: The T2*-weighted MR sequence can be useful in rapid detection of CVT and may enable the diagnosis to be made prior to MR venography. This is particularly important in clinically unsuspected patients, in whom MR venography is rarely obtained.     

脑静脉系统血栓形成的临床特点

目的探讨脑静脉血栓形成(CVT)的临床特点。方法回顾性分析27例CVT患者的临床资料。结果本组患者中25例有发病诱因(包括妊娠或产褥期18例,高热、腹泻5例等),平均年龄(29.7±9.3)岁;多以急性(7例,25.9%)、亚急性(19例,70.4%)起病。以头痛为首发症状23例(91.7%),伴呕吐21例,12例出现意识障碍,均出现不同部位的神经功能缺损表现。腰穿CSF压力增高21例。血常规检查异常22例(81.5%),凝血功能异常13例(48.2%)。影像学检查[CT、MRI、MR静脉血管成像(MRV)]显示,均有不同程度的颅内静脉或静脉窦受累,其中上矢状窦受累最多(77.8%)。24例采用肝素抗凝治疗,2例用溶栓治疗。17例痊愈,4例好转,6例死亡(其中4例并发出血性梗死,2例伴大脑大静脉血栓形成)。结论 CVT继发于循环血液不足及血液高凝状态,以急性或亚急性起病,主要表现为颅内压增高综合征,死亡率较高;MRI和MRA是早期诊断的有效手段,早期肝素抗凝治疗可取得良好疗效。     

Cerebral venous thrombosis in Down's syndrome

We report the first case of cerebral venous thrombosis (CVT) diagnosed in an adult with Down's syndrome (DS). A 25-year-old man with DS was admitted because of a generalized tonic–clonic seizure and prolonged postictal period. Cerebral magnetic resonance imaging (MRI) and MR venography revealed CVT. No particular cause of the thrombosis was identified. CVT may be an unusual cause of stroke in DS.     

T2*-Weighted MRI Detected Dilated Cerebral Veins in a Patient with Acute-Phase Cerebral Venous Sinus Thrombosis—A Case Report

We describe a 45-year-old man who presented with nausea, vomiting, and strong occipital headache on the right side. Although no abnormalities on neurological examination or computed tomography imaging were found on admission, peripheral blood cell counts showed polycythemia (hemoglobin 20.6 g/dL) and electrocardiography demonstrated atrial fibrillation. Therefore, anticoagulant treatment with heparin was started immediately. On the following day, the occipital headache continued. Brain T2*-weighted (T2*WI) magnetic resonance imaging (MRI) and, to a lesser extent, susceptibility-weighted imaging showed dilation of numerous cortical veins, suggesting the possibility of cerebral venous thrombosis (CVT). MR venography (MRV) showed a deficit of the right transverse sinus. Contrast-enhanced MRI revealed partial defects of the right transverse sinus, and led to the definite diagnosis of CVT, and the anticoagulation therapy was continued. On day 7 the headache disappeared, and MRV on day 16 showed the recanalization of the right transverse sinus. There were no complications subsequent to the CVT. On day 25, the patient was discharged with no after-effect. We speculate that the dilation of cortical veins on T2*WI is a helpful sign in detecting acute-phase CVT.     

脑静脉窦血栓形成的MR诊断及MRV的应用

目的探讨脑静脉窦血栓形成（cerebral venous sinus thrombosis, CVST）的MR征象及磁共振脑静脉系血管成像（magnetic resonance venography, MRV）的技术方法。方法4例脑静脉窦血栓形成患者,男2例,女2例,年龄32～51岁,全部经常规MRI及MRV检查,2例患者行增强扫描,全部患者经DSA检查证实。结果4例患者平扫SE序列均可见静脉窦内正常流空信号消失,代之以异常等或高信号。出血性脑梗死3例;广泛脑肿胀及脑水肿1例。MR增强可见静脉窦异常低信号或闭塞;对比增强磁共振血管造影检查（contrast enhanced magnatic resonance venography, CE-MRV）见受累静脉窦腔内血流信号不规则或信号完全消失。结论MRI结合3D-CE-MRA是诊断脑静脉窦血栓形成的有效手段。     

Cerebral venous thrombosis in a gentleman presenting with fever, convulsion and frontotemporal haemorrhages.

Cerebral venous thrombosis (CVT) is an uncommon but serious type of stroke. Thrombosis may involve the cortical or deep veins or the venous sinuses. The presenting clinical features are non-specific. We report a 48-year-old man with CVT who presented with fever, bitemporal throbbing headache, and generalised convulsion. Computed tomography (CT) of the brain revealed acute haemorrhages over right anterior frontal and posterior temporal regions with surrounding oedema and right anterior temporal subcortical oedema. The initial diagnosis was herpes simplex encephalitis. Absence of venous flow over the right transverse and sigmoid sinuses during the venous phase of digital subtraction angiography (DSA) revealed CVT. He was anti-coagulated for 6 months. An underlying cause of CVT was not detected. A high index of suspicion is required when risk factors of CVT are present. CT brain may be normal or showing non-specific findings. Magnetic resonance imaging plus venography, CT venography, or DSA is diagnostic.     

脑静脉及静脉窦血栓形成的临床特点与影像学分析

目的 探讨脑静脉及静脉窦血栓形成（CVT）的临床表现、影像学特征以及诊断治疗方法。方法 回顾性分析52例CVT病例的临床特点及脑脊液、影像学特征,并结合文献复习其诊断治疗方法。结果 此病可见于各个年龄段,以中青年女性稍多,妊娠、感染、免疫性疾病等为常见病因,部分病例病因不明。以头痛为首发症状者多见（82.7％）,其次为癫发作（3.85%）或其他局灶性神经功能缺损（13.5%）。腰椎穿刺检查多数病例压力升高（86.7%）,脑脊液蛋白和白细胞数正常或轻度升高。典型病例颅脑CT可见到血栓局部条索状高密度影或伴有出血和水肿。MRI平扫可见病变静脉窦异常血栓信号。MRV和DSA可见病变静脉窦显影不良或不显影。经抗凝、降低颅内压等对症治疗,部分病例行溶栓治疗后,多数病例病情好转(86.5%),少数病例病情恶化(5.7%)。结论 中青年患者表现为头痛、呕吐、伴或不伴局灶性神经功能缺损,腰椎穿刺检查提示颅内压升高时应高度警惕CVT可能。围产期女性为高危人群。疑似病例应尽早行颅脑CT和MRI检查以明确诊断,DSA是CVT诊断的金标准并可指导溶栓路径。治疗上早期应用抗栓治疗,严重病例经动脉或静脉行局部溶栓治疗可以缓解临床症状,改善预后。此外还应根据病因进行针对性治疗。     

脑静脉系统血栓形成43例临床分析

目的 探讨腩静脉系统血栓形成(cerebral venous thrombosis,CVT)的病因、临床特征、诊断及治疗.方法 回顾性分析43例CVT患者临床资料,总结CVT的临床特点、影像学特征、诊断、治疗及转归.结果 CVT多见于中青年,多为急性起病,大部分可找到相关病因,最常见的首发症状为头痛,MRI联合MRV能清晰地显示静脉系统形态及阻塞情况,DSA能清楚显示静脉系统血栓的部位及继发于CVT的动静脉瘘.早期诊断及应用抗凝治疗是取得良好预后的关键.结论 CVT的病因多样,临床表现缺乏特异性,MRI联合MRV检查是目前CVT诊断及随访的重要检杳方法 ,对原因不明的颅内高压患者需行相应检查,一旦确诊,应予抗凝治疗.     

外伤性颅内静脉窦血栓形成的MRI诊断

目的探讨磁共振成像(MRI)结合磁共振静脉成像(MRV)在外伤性颅脑静脉窦血栓形成中的诊断价值。方法回顾性分析28例经临床及影像学诊断为外伤性颅脑静脉窦血栓形成的 MRI与MRV资料。磁共振均行常规SE序列T1WI、T2WI以及液性衰减反转恢复序列(FLAIR)扫描,并全部行二维时间飞跃法静脉成像(2d-TOF MRV)检查。结果外伤性静脉窦血栓形成最常累及上矢状窦、下矢状窦、横窦,表现为受累静脉窦流空效应消失,为不同信号的血栓所阻断。MRV则表现为受累静脉窦管腔的狭窄、中断以及属支的迂曲扩张。结论 MRI结合MRV能无创性的同时显示外伤性颅脑静脉窦血栓形成与脑挫裂伤,为外伤性颅脑静脉窦血栓形成的首选检查方法。     

Computer-Assisted Intraaneurysmal Thrombus Visualization

OBJECTIVE: Improved visualization of intraaneurysmal thrombi can contribute to understanding their impact on clinical courses and treatments. Digital subtraction angiography (DSA) demonstrates the hemodynamic portion of aneurysm domes and vasculature structures and has been considered by many to be the principal technique used for aneurysm diagnosis. An intraaneurysmal thrombus may be visualized as a filling defect on DSA, but DSA does not reliably indicate the presence of an intraaneurysmal thrombus or its details. Computerized tomography (CT) and magnetic resonance (MR) imaging may have advantages over DSA, particularly because of their capacity to visualize soft tissue. Hence, we investigated the reconstruction of MR and CT images and compared it to DSA for assessment of intraaneurysmal thrombi. METHODS: Thirty-one patients with 34 aneurysms were enrolled. The entire group was examined with DSA. Sixteen cases were also examined with MR imaging; the remaining 15 were examined with CT imaging. Images of intraaneurysmal thrombi were rendered from corresponding MRI and soft tissue scans using CT. Intracranial vessels and aneurysms were defined from MR and CT angiography. Whole images were linked via imaging software for the reconstruction of vasculature structures. Images were superimposed to produce visualizations of thrombi situated in aneurysmal bodies. RESULTS: Reconstruction of the MR and CT images clearly demonstrated the presence and details of intraaneurysmal thrombi in 9 (26.4 %) of 34 aneurysms. DSA detected only 4 (11.7 %) of the cases as a filling defect. Significant differences in thrombus visualization were observed between DSA used alone or in conjunction with either MRA (P = .02) or CTA (P = .04) images. Mean volume of thrombosed aneurysms was 3.2 +/- 0.84 mL (mean +/- SEM) and thrombosis volume was 0.9 +/- 0.31 mL. Aneurysm and nested thrombus volumes were highly correlated (r = 0.987; P < .001). CONCLUSION: Intraaneurysmal thrombi were clearly visualized by computerized MR and CT image reconstruction. MR and CT were superior to DSA alone in demonstrating the presence of intra-aneurysmal thrombi. Computer-assisted 3-D visualization can be invaluable in understanding the shape and volume of intraaneurysmal thrombi, which may contribute to more accurate assessment and effective treatment of aneurysms cases.     

Cerebral venous thrombosis associated with tentorial subdural hematoma during oxymetholone therapy

Androgen was reported to cause cerebral venous thrombosis (CVT) during replacement therapy for aplastic anemia. Oxymetholone, a synthetic androgen analogue, has been widely used in the treatment of aplastic anemia. A 40-year-old woman with aplastic anemia visited our hospital because of severe headache, nausea, vomiting, blurred vision and diplopia for a period of 1 month. She had taken oxymetholone for 2 years. Neurological examination revealed bilateral papilledema and bilateral sixth nerve palsies. Brain magnetic resonance imaging (MRI), performed at the time of admission, demonstrated left-sided tentorial SDH, and focal cerebral thrombosis of the left superficial sylvian vein and sigmoid sinus. MR venography revealed multiple irregularities in the superior sagittal sinus and left transverse sinus. CVT with tentorial subdural hematoma (SDH) caused by oxymetholone was strongly suggested. Oxymetholone was immediately discontinued, and her symptoms and signs disappeared. Because of the thrombocytopenia, anticoagulation was not started. She was discharged and visited the outpatient clinic without neurological symptoms for 6 months. This report supports the cautions given about the risk of CVT with oxymetholone supplementation in aplastic anemia. To the best of our knowledge, this is the first report of CVT associated with tentorial SDH that was probably caused by oxymetholone.     

Case of straight sinus venous thrombosis presenting as depression and disorientation due to bilateral thalamic lesions]

A 45-year-old man was admitted to our hospital because of progressive inactivity and mild disturbance of consciousness which appeared two weeks ago. Brain CT revealed symmetric hypointensity of bilateral thalamus, and the lesion appeared hyperintensity on T2 weighted MRI image. He was first considered as immune-mediated cerebritis, and steroid pulse therapy was applied, but the clinical features were not improved. The diagnosis of cerebral venous thrombosis was established, when MR venography (MRV) showed severe stenosis in straight sinus. Consciousness was improved after the start of anticoagulation therapy, but mild dementia was remained as a sequela. MRV was useful to distinguish straight sinus thrombosis from cerebritis in this case.     

中国人脑静脉及静脉窦血栓形成的临床特点

目的 分析中国人脑静脉及静脉窦血栓形成（CVT）的临床特点,以提高国内脑静脉及静脉窦血栓形成的早期诊断率,减少误诊率及死亡率。方法 对我国1998～2006年文献报道的461例CVT患者的病因、临床表现、影像学特征、治疗经过及预后进行回顾性分析。结果 CVT发病年龄多在20～40岁,多数为急性或亚急性发病。其病因中,继发于感染病灶的占18％;非感染性原因占60%左右,其中产褥期发病占39.7％。上矢状窦血栓形成是最常见的CVT。CVT主要临床表现：头痛占88%,视乳头水肿占48.9%,局灶性或全身性的癫占27.6％,神经系统局灶体征占21.6%和意识障碍占18.5%。目前抗凝溶栓治疗是比较公认的治疗CVT的方法,可使CVT的死亡或完全致残率下降15%,超过80%的患者可以存活,但仍有13%～20%的患者死亡。结论 中国人CVT的临床表现变异很大且缺乏特异性,常见于育龄期妇女。因此,关注患者是否存在CVT发生的高危因素,尽早行颅脑CT、MRI、MRA或DSA检查,明确诊断后应积极地抗凝治疗,并纠正病因、对症治疗。溶栓联合介入治疗可能具有更好的临床前景。     

Vernet's Syndrome Associated with Internal Jugular Vein Thrombosis

Our objective is to present a case of Vernet's syndrome (cranial nerve (CN) IX, X, and XI palsy) associated with cerebral venous thrombosis (CVT) in an internal jugular vein. The patient presented with acutely developed dysphagia. The weakness of the left sternocleidomastoid and trapezius muscles was observed. The initial magnetic resonance imaging and computed tomography (CT) with contrast enhancement showed contrast-filling defect in the left internal jugular vein inside the jugular foramen. The magnetic resonance venography with contrast enhancement revealed a partial filling defect in the left sigmoid sinus and total occlusion of the left internal jugular vein. Under the diagnosis of CVT associated with CN IX, X palsy, anticoagulation therapy with low-molecular-weighted heparin was initiated. Despite the continued anticoagulation therapy for 3 months, neither the burden of thrombosis in the left sigmoid sinus and internal jugular vein on neck CT nor dysphagia symptoms improved. Clinicians need to be aware of internal jugular venous thrombosis as one of the differential diagnoses in Vernet's syndrome in patients in a hypercoagulable state. Further reporting of similar cases is needed to confirm the association between CVT and Vernet's syndrome.     

Neonatal idiopathic cerebral venous thrombosis: an unrecognized cause of transient seizures or lethargy.

Seven neonates who presented with either lethargy (four infants) or seizures (three infants) were found by magnetic resonance (MR) phase imaging to have idiopathic cerebral venous thrombosis (CVT). Examination showed only hypotonia or hyperreflexia. The presence of CVT was suggested by unenhanced cranial computed tomographic (CT) scans. Conventional MR T1- and T2-weighted images often indicated more extensive thromboses than were suggested by cranial CT. In all infants, MR phase imaging confirmed thromboses by establishing absence of blood flow in cerebral veins or sinuses. No infant received anticoagulation. Lethargy slowly resolved and seizures did not recur. Normal development has been observed thus far in brief follow-up. The occurrence of seven infants with idiopathic neonatal CVT within a 3-month period indicates that CVT may be a cause of neonatal seizures or lethargy of unclear cause. MR phase imaging provides a powerful, noninvasive means of confirming the diagnosis. Treatment with anticoagulants does not appear necessary.     

颅内静脉窦血栓形成（9例临床报道）

目的:探讨脑静脉血栓形成(CVT)的临床特点与影像学表现。方法:回顾性分析本院9例CVT的临床及影像学资料。结果:①临床表现:头痛(77%)、癫样抽搐(66%)、局灶性神经功能缺失(66%)、视乳头水肿(44%)、不同程度意识障碍(22%)。②影像学资料及治疗转归:1例头颅CT示弥漫性脑水肿,蛛网膜下隙出血合并多发出血性脑梗死,因颅内压持续增高,予外科手术行去骨板减压术,见大脑表面浅静脉怒张呈绳索状并多数点片状出血灶。8例行头颅MRI和MRV,显示直接征像8例、间接征像6例。其中2例同时行DSA,均显示多个静脉和静脉窦充盈缺损。静脉血栓部位:上矢状窦合并浅静脉血栓1例,上矢状窦合并侧窦及多处静脉受累7例,直窦血栓1例。7例行肝素抗凝等对症治疗、1例行血管内局部溶栓、1例行矢状窦手术取栓并抗凝治疗。症状缓解至痊愈7例,病死2例。结论:首诊时诊断不明确,可先作头颅CT,排除颅内非CVT性病变,临床已拟诊CVT时,应首选MRI+MRV,进行综合判断是目前诊断和随访CVT的最好方法,婴幼儿CVT常表现为癫发作起病,提示CVT是婴幼儿重要的未被识别的性发作原因之一。     

脑静脉窦血栓形成的诊断与血管内治疗

目的 探讨脑静脉窦血栓形成的诊断和血管内溶栓治疗。方法 对8例以顽固性头痛、呕吐伴或不伴局灶性神经功能缺损或癫发作为主要表现的患者，采用颅脑MRI和脑血管造影检查确定诊断，并施行经颈内动脉、静脉窦内接触性溶栓或静脉窦内支架成形术协同抗凝治疗。结果 MRI显示相应脑静脉窦区出现长T2WI，短T1WI信号，DSA显示脑静脉窦闭塞、静脉侧支循环建立和脑动静脉循环时间延长。治疗后静脉窦完全或部分再通，脑循环时间接近正常，临床病情显著缓解。结论 血管内介入治疗可能是脑静脉窦血栓形成最有效的治疗方法之一，有待大样本研究证实。     

Magnetic resonance venography in idiopathic pseudotumor cerebri.

OBJECTIVE: To inform clinicians about the use of magnetic resonance (MR) venography in idiopathic pseudotumor cerebri. MATERIALS AND METHODS: A prospective study to evaluate for the presence or absence of dural sinus thrombosis using MR imaging and MR venography of the brain in 22 consecutive young, female, overweight patients with typical pseudotumor cerebri. RESULTS: None of the 22 MR imaging and MR venography studies showed venous sinus thrombosis. CONCLUSION: Magnetic resonance venography might not add significantly to the evaluation of typical idiopathic pseudotumor cerebri but may be indicated in atypical cases (e.g., male, thin, or elderly patients).     

外伤性脑静脉窦血栓的临床诊治

目的 探讨外伤性脑静脉窦血栓的诊治方法。方法 对近两年来临床工作中发现的27例外伤性脑静脉窦血栓患者资料进行回顾性分析。所有病例均采用核磁共振成像（MRV）证实，行尿激酶静脉溶栓治疗，首齐20万U，每日增加5万U。最大剂量达100万U。结果 19例再通，7例建立侧支循环，1例死亡。结论 对临床工作中出现的腰穿颅内压大于300mm H20的病例、跨窦骨折的病例、病情平稳后又出现反复（如头痛加剧、呕吐等）而复查头颅CT无异常的病例，应高度怀疑脑静脉窦或深静脉血栓形成。MRV成像是脑静脉安或深静脉血栓诊断的首选方法。     

Diffusion-weighted mr in cerebral venous thrombosis

The diagnosis of cerebral venous thrombosis is often difficult both clinically and radiologically and until now there is no method available to predict if brain lesions, detected clinically and using conventional brain imaging methods, may lead to full recovery, as expected in vasogenic edema or ischemic infarcts and even a hematoma. New fast neuroimaging techniques such as diffusion-weighted imaging (DWI) are sensitive to different reasons of changes in local tissular water concentration thus giving further insight into the pathophysiological mechanism as well as prognosis of cerebral venous thrombosis. We report the cases of 18 consecutive patients with a diagnosis of cerebral venous thrombosis based on clinical and imaging criteria. All patients underwent magnetic resonance imaging (MRI) of the brain, which comprised isotropic diffusion-weighted MR. Diffusion-weighted MRI showed positive findings in 17/18 cases. In 7 cases the clot could be directly visualized as an area of hyperintensity in the affected vein on DWI. In 7 cases DWI showed areas of signal loss corresponding to hematomas. In 6 cases DWI showed changes in signal intensity that were more subtle. In 4 cases of superficial venous thrombosis, there were areas of decreased ADC values (0.65-0.79 x 10(-3) mm(2)/s) whereas in 2 cases of deep venous thrombosis, increased DWI intensities could be found that corresponded to both an increase and a decrease in ADC, corresponding to a coexistence of cytotoxic and vasogenic edemas. Diffusion-weighted MRI can demonstrate directly the presence of an intravenous clot in a select number of patients. It can also demonstrate early ischemic changes, and can differentiate conventional T2-weighted MR areas of cytotoxic from vasogenic edema.