Neuroimaging of Cerebral Venous Thrombosis

Early and accurate diagnosis of cerebral venous thrombosis (CVT) is possible with the help of computed tomography (CT) scan and magnetic resonance imaging (MRI). Empty delta sign on postcontrast CT is present in only up to 30% of the cases. The role of CT venography is not yet established, but it is emerging as an effective modality for diagnosis of CVT. T2* MRI sequence is superior to spin echo in detecting CVT and small hemor rhages. MR venography is considered the technique of choice for diagnosis and follow-up of CVT, but in certain cases, MRI could be superior as it shows the thrombus itself and not just the absence of signal as seen on MR venography. Diffusion-weighted imaging is a relatively new MRI technique that is extremely sensitive in detecting acute arterial strokes and can distinguish cytotoxic and vasogenic edema. The presence of hyperintense signal on diffusion-weighted imaging in the occluded veins or sinuses at the time of diagnosis may predict a low rate of vessel recanalization. Contrast angiography should be strongly considered if isolated cortical vein thrombosis is suspected.     

Seizures and cerebral infarction in the full-term newborn

Cerebral arterial infarction is a more common cause of neonatal seizures than has been previously appreciated. In 50 full-term newborns with seizures studied, 7 had cerebral infarction which was the second most common definable cause of seizures. We describe these 7 full-term infants with cerebrovascular accidents who presented with focal or generalized seizures. Obstetrical histories were normal in 5 of these patients. Their neurological examinations demonstrated lethargy and generalized hypotonia. Electroencephalograms demonstrated focal abnormalities in 4 infants. Computed tomographic scans in the first week of life showed infarctions in 6 newborns and in another at age 6 months. Neonatal stroke should be considered as a cause of seizures in a full-term newborn in spite of a normal obstetrical history and a nonfocal neurological examination.     

Diffusion-weighted imaging in neonatal cerebral infarction: clinical utility and follow-up

We describe the clinical utility of echo-planar diffusion-weighted imaging in neonatal cerebral infarction. Eight full-term neonates aged 1 to 8 days referred for neonatal seizures were studied. Patients were followed for a mean of 17 months with detailed neurologic examinations at regular intervals. Head computed tomography (CT) and conventional magnetic resonance (MRI) and diffusion-weighted images were obtained. Percent lesion contrast was evaluated for 19 lesions on T2-weighted and diffusion-weighted images. Follow-up conventional MRIs were obtained in seven patients. The findings on diffusion-weighted imaging were correlated with CT and conventional MRI findings as well as with short-term neurodevelopmental outcome. Four patients had focal cerebral infarctions. Four patients had diffuse injury consistent with hypoxic-ischemic encephalopathy. Percent lesion contrast of all 19 lesions was significantly higher on diffusion-weighted images when compared with T2-weighted images. In five patients, there were lesions visualized only with diffusion-weighted imaging. In all patients, there was increased lesion conspicuity and better definition of lesion extent on the diffusion-weighted images compared with the CT and T2-weighted MR images. In seven of eight patients follow-up imaging confirmed prior infarctions. Short-term neurologic outcome correlated with the extent of injury seen on the initial diffusion-weighted imaging scans for all patients. Diffusion-weighted imaging is useful in the evaluation of acute ischemic brain injury and seizure etiology in neonates. In the acute setting, diffusion-weighted imaging provides information not available on CT and conventional MRI. This information correlates with short-term clinical outcome.     

Intracranial hemorrhage in the full-term neonate and young infant: correlation of the location and outcome

The cranial computed tomography (CT) and outcome for 13 full-term neonates and 12 young infants with intracranial hemorrhage (ICH) were studied. The full-term neonates had perinatal asphyxia or neurological signs such as seizures. All infants were breast-fed and showed bleeding diathesis. In the full-term neonates there was a high incidence of intraventricular hemorrhage (IVH) and hemorrhage around the falx. The location of the hemorrhage on CT and brain pathology suggested that the original site of IVH might be the choroid plexus vessels in the lateral ventricle or in the subependymal layer. On the other hand, the sites of ICH in infants were multifocal compared with those in full-term neonates. Subdural hemorrhage (SDH) was seen more frequently and IVH less frequently in infants than in full-term neonates. The cases with SDH frequently showed accompanying cerebral infarction followed by porencephaly. Thus, SDH with cerebral low density on CT may predict a poor prognosis.     

Magnetic resonance imaging in neonates with total asphyxia

Magnetic resonance (MR) findings in cases of total asphyxia, whose lesions are mainly in the brainstem and deep nuclei, have not been clarified. In this study, we investigated MR images in neonates with total asphyxia. MR images of six infants (three males and three females; gestational age, 35–39 weeks; birth weights, 1880–3572 g) with total asphyxia were examined. In all subjects, neonatal cortical MR lesions were limited to the hippocampus with highlighting on T1-weighted imaging (T1-WI). The neonatal MR lesions of the cerebral white matter were limited to the white matter between the insula and putamen in four infants, and were diffusely involved in two infants. The ventral lateral nucleus of the thalamus was hyperintense on T1-WI in all of the subjects. Other nuclei in the thalamus, the globus pallidus and the putamen were involved in neonatal MR images of all subjects. High intensity areas on T2- weighted imaging were observed at the dorsal areas in the midbrain, pons and medulla oblongata in all or most of the subjects at the neonatal period. Also, high intensity areas on T1-WI were observed in the tegmentum of the pons and the midbrain in five cases. Neonates with total asphyxia had lesions mainly in the tegmentem of the brainstem, thalamus, putamen and globus palludus. Some of the infants had extensive lesions of the white matter.     

Neonatal cerebral infarction

Neonatal cerebral infarction in term infants has many possible causes, including bacterial meningitis, inherited or acquired coagulopathies, trauma, and hypoxia-ischemia. However, a specific cause often cannot be identified. Neurologic symptoms in the neonatal period are often subtle and nonspecific, even in infants with large infarctions involving an entire cerebral artery distribution. The most common presenting symptom is focal motor seizures of the contralateral limbs. Cranial magnetic resonance imaging, especially with diffusion-weighting, is the most sensitive imaging modality, although ultrasonography with Doppler imaging of cerebral blood flow is useful in the neonate who is too ill to transport. Neurodevelopmental outcome is often surprisingly good, with many infants making a complete recovery of motor function. The effect of neonatal stroke on cognitive function, especially language acquisition and emotional and social development, has not been fully established.     

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.     

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.     

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。     

Perinatal cerebral infarction

The diagnosis of perinatal cerebral infarction, although frequently suggested clinically, has been made most commonly at postmortem examination; few infants surviving stroke are reported in the literature. We evaluated 18 infants with perinatal cerebral infarction in a recent twelve-month interval. Seven were preterm neonates, 6 of whom had experienced neonatal intraventricular hemorrhage. Three full-term infants were thought to have experienced cerebral infarction in utero and had evidence of well-defined strokes on computed tomographic scans performed shortly after birth. Eight infants developed stroke at term. The most common cause of cerebral infarction in our series was perinatal asphyxia. Fourteen of the infants were seen with neonatal seizures. Fourteen of the 18 have died or are faring poorly at 4 to 12 months of age (corrected).     

Congenital varicella syndrome: case with isolated brain damage

We report a case of congenital varicella syndrome after maternal infection during the 10th week of pregnancy. None of the typical abnormalities were manifested at birth; however, the child experienced neonatal tonic convulsions that evolved to refractory focal epilepsy with adversive, complex partial, and secondarily generalized seizures. At the age of 5 years, after a prolonged generalized seizure following cranial trauma, cranial computed tomography (CT) was performed. It led to the misdiagnosis of post-traumatic intracerebral hemorrhage. Afterwards, because of persistent seizures and developmental delay with mild or slight intellectual deficit, the next CT and magnetic resonance imaging (MRI) investigation at 8 years of age disclosed massive malformation of the left cerebral hemisphere. The serologic evidence of varicella-zoster virus-specific IgG antibodies without a history of varicella disease after birth and maternal infection during early pregnancy were crucial to diagnosing the rare syndrome of congenital varicella consisting of isolated brain damage.     

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。     

Seizures in cerebral vein and dural sinus thrombosis

To describe early symptomatic and late seizures in a cohort of patients with acute cerebral vein and dural sinus thrombosis (CVDST) and to identify their determinants, we performed a prospective registry and follow-up study of CVDST patients admitted to 20 Portuguese hospitals, from June 1995 to June 1998. Of 91 registered patients, 31 (34%) had early symptomatic seizures; 29 (31.9%) as a presenting feature and 2 (2.1%) after admission. Early symptomatic seizures were more frequent in patients with motor and sensory deficits and in those with focal oedema/ischaemic infarcts or haemorrhages on admission CT/MR. On multivariate logistic regression analysis, sensory defects (OR = 7.8; 95% CI = 0.8-74.8) and a parenchymal lesion on admission CT/MR (OR = 3.7, 95% CI = 1.4-9.4) were found to be significant predictors of early symptomatic seizures. Seizures were directly related to acute death in 2 patients. Eight (9.5%) patients had late seizures, which were multiple in 4 (4.8%). Late seizures were more frequent in patients with early symptomatic seizures and with haemorrhage on admission CT/MR. Neither early symptomatic seizures nor late seizures were related to functional prognosis at the last follow-up (median = 1 year). There is a moderate risk of seizure recurrence early in the course and during the first year after CVDST. Seizures can be a cause of acute death, but might not have an independent influence on functional outcome. Pharmacological prevention of seizures after CVDST should probably be limited to patients with early symptomatic seizures and cerebral lesions on admission CT/MR.     

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.     

Anticardiolipin antibodies: a study in cerebral venous thrombosis

OBJECTIVES: Anticardiolipin antibodies (aCL) have been recognized as a marker for an increased risk of thrombosis. There are no documented reports from India on the prevalence of aCL in patients with cerebral venous thrombosis (CVT). Our study aimed at establishing the prevalence of these antibodies in patients with CVT and evaluating their clinical significance. SUBJECTS AND METHODS: Thirty-one patients with CVT diagnosed by angiography and/or cranial CT were investigated for the presence of aCL along with 31 age- and sex-matched normal controls. All subjects had no overt evidence of systemic lupus erythematosis or related autoimmune disorders. The titres of IgG and IgM type of aCL were estimated in the sera using a solid phase enzyme-linked immunosorbent assay. RESULTS: Anticardiolipin antibodies were detected in 22.6% of CVT patients compared to 3.2% of normal controls (95% confidence interval (CI) 1.01 to 75.65). Five CVT patients had both IgG and IgM antibodies, and 2 had only IgG antibodies. The aCL positive group did not differ from the aCL-negative group with respect to the clinical characteristics and the demographic and risk factor profile. CONCLUSION: The findings suggest that anticardiolipin antibodies are a risk marker for cerebral venous thrombosis. Further studies on a larger group of patients are needed to establish the role of aCL in the pathogenesis of CVT.     

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.     

The evolution of ischemic cerebral infarction in infancy: a sonographic evaluation

Cranial sonography provides a noninvasive, portable method for imaging the infant brain. This study describes the time-dependent, sonographic findings of infantile cerebral infarction, as well as computed tomographic (CT) scan and neuropathologic confirmation. Three hundred ninety-five infants under 18 months of age were sonogrammed over a period of 18 months. Three infants were diagnosed by cranial sonography and confirmed by CT scan and/or autopsy to have acute ischemic cerebral infarcts. The cases were followed with serial cranial sonograms for up to 18 months of age. The acute sonographic findings included a hyperechoic zone around the infarcted tissue. The subacute infarct had a checkerboard pattern, while the chronic infarcts were anechoic.     

Myelination patterns on magnetic resonance of children with developmental delay.

Magnetic resonance (MR) imaging was performed in 30 children with unexplained developmental delay who had associated neurological abnormalities such as seizures, spasticity, hypotonia, ataxia or poor vision. No child had a history of regression, preterm birth or neonatal cerebral injury. CT scans were performed before MR in all cases and were either normal or showed only mild atrophy. At least two MR sequences were obtained for all patients. Nine children had delayed or absent myelination on MR, one had patchy white-matter abnormalities, and in one patient myelination was topographically normal, but of inappropriately low signal intensity. MR was abnormal in six of seven children who had abnormal brainstem auditory evoked potentials (BAEP), and was normal in nine of 11 patients who had a normal BAEP. MR may have a useful r?le in demonstrating abnormal white-matter maturation in children with unexplained neurodevelopmental delay, particularly when abnormalities are found on BAEP studies.     

Magnetic resonance imaging and magnetic resonance spectroscopy in isolated sulfite oxidase deficiency

Isolated sulfite oxidase deficiency is a rare genetic neurometabolic disease. The first symptoms of this disorder (similar to symptoms of ischemic events) may lead to misdiagnosis and to subsequent birth of affected children in these families. This study characterizes the magnetic resonance (MR) imaging and (for the first time, to our knowledge) the MR spectroscopy features of isolated sulfite oxidase deficiency to provide a means for early and correct diagnosis. Three patients with isolated sulfite oxidase deficiency are studied who manifested intractable seizures and severe hypotonia in the immediate postnatal period with an unknown diagnosis, despite extensive workup. MR imaging and proton MR spectroscopy examinations were performed early in the neonatal period in 2 infants and after 5 months in the third infant. The prominent MR features were early cystic white matter damage, accompanied by profound cerebral atrophy in the third infant. Compared with hypoxic-ischemic disorder, MR findings in isolated sulfite oxidase deficiency demonstrate a more severe condition, without subsequent recovery. The MR spectroscopy studies indicate early onset of energetic and metabolic imbalance. Urine stick findings demonstrated high sulfite levels in 2 patients, and the final diagnosis was subsequently made based on molecular, biochemical, and genetic findings. Magnetic resonance imaging and MR spectroscopy measurements may help differentiate isolated sulfite oxidase deficiency from hypoxic-ischemic condition in patients in whom this diagnosis is not clinically suspected and may lead to further genetic antenatal inquiry that might prevent the birth of other infants affected with this severe and incurable congenital disease.