Presenting features, co-morbid conditions, treatment, and outcome of cerebral venous sinus thrombosis (CVST) in a consecutive series of children are reported from Department of Paediatric Neurology, Bristol Royal Hospital for Children, UK. Twenty-one children (10 male) were diagnosed with CVST (using electronic databases and international codes) and treated in a single pediatric neurology center over a period of 8.25 years. Ages ranged from 1.4 to 16.9 years (median 7.1 years); neonates were not included. Presenting symptoms in order of prevalence were headache in 15 [71.4%], vomiting (14 [66.6%]), visual disturbance (8 [38.1%]), lethargy/malaise (4 [19.1%]), irritability (3 [14.3%]), limb weakness (2 [9.5%]), unsteady gait (2 [9.5%]), and seizures in 2 [9.5%] patients. Neurological abnormal signs included papilledema in 16 [76.2%], fever (6 [28.6%]), sixth nerve palsy (6 [28,6%]), hemiparesis (5 [23.8%]), decreased level of consciousness (3 [14.3%]), visual field defect (2 [9.5%]), and ataxia in 2 [9.5%]. Patients without papilledema were the youngest, 3.4 years or less. Ear infection (otitis media/mastoiditis) was the most frequent etiological factor, in 13 [61.9%] patients. Other predisposing factors were anemia in 4 and thrombocytosis in 3, nephrotic syndrome in 3, dehydration (3), oral contraceptive (2), group A streptococcal septicemia (2), and pituitary germinoma in 1. Thrombosis was located in superficial sinuses in 21 and deep sinuses in 6. Transverse lateral sinuses were involved in 19 and superior sagittal in 10. CT scans were falsely negative in five of 16 children examined. MRI/MRvenography was diagnostic in all patients. All 21 patients received heparin infusions, and 4 severe cases were treated by local thrombolysis using tissue plasminogen activator, with benefit in 3. All 15 children with infection received antibiotics. Adverse outcome occurred in 45%: 2 died, 8 were treated for chronic intracranial hypertension, 2 had residual hemiparesis, and 1 residual sixth nerve palsy. 
COMMENT. Cerebral venous sinus thrombosis (CVST) is rare in children and occurs more frequently in neonates. In one recent study of 70 patients, ages ranging from 6 days to 12 years, 25 (35%) were neonates . Seizures were the most frequent presenting feature, occurring in 59%. This finding contrasts with the present series that excludes neonates and in which seizures occurred in only 9.5%. Seizures were reported in 58% of 160 consecutive children (newborn to 18 years of age) with CVST enrolled in a Canadian Registry in six years from 1992-1998. Occurrence of seizures was followed by a poor outcome . A report of four neonates with CVST and seizures who developed infantile spasms with hypsarrhythmia at 7-11 months of age demonstrates the poor long-term outcome of neonatal CVST that presents with seizures. 
Diagnosis of CVST is frequently overlooked because presenting symptoms are varied and nonspecific. Headache is the most frequent presenting symptom in older children and adults, affecting 95% of patients with isolated lateral sinus involvement . Presence of comorbid factors, especially ear infection, should alert the probability of CVST in a child presenting with headache, vomiting and papilledema. Imaging with CT is unreliable, with a high incidence of false negatives, and MRI/MRV is recommended but sometimes difficult to interpret due to anatomical variation. The right transverse sinus is commonly dominant, and the left transverse sinus may be narrowed and atretic. [6, 7]
Dramatic increase in venous thromboembolism (VTE) is reported in Children’s Hospitals in the United States from 2001 to 2007 . The increase was observed at all ages, including neonates. Of 15,000 cases, 1206 involved the intracranial venous sinuses. Pediatric malignancy was the most common comorbid condition associated with recurrent VTE.