<unk><unk>  thrombosis(CVT)is thrombosis of<unk>  veins, a rare form of stroke which is different from arterial strokes. CVT incidence is 1.3 in per 1,00,000/year in developed countries. Young children and women especially pregnant/puerperium have a higher frequency of CVT. Due to the wide spectrum of clinical features, CVT frequently gets misdiagnosed as other strokes. Commonly known risk factors and causes of<unk><unk>  thrombosis are<unk>  thromboembolism, thrombophilia (especially antithrombin deficiency, protein C and S deficiency and factor V Leiden mutation), pregnancy, oestrogen therapy/oral contraceptives, hypercoagulability as part of inflammatory disease, head trauma, local infections and underlying cancer. Pathophysiology of CVT includes two mechanisms including thrombosis of<unk>  veins creating local edema and<unk>  infarction; intracranial hypertension created by increased<unk>  pressure and decreased absorption of CSF. Clinical presentations of CVT can be categorized into 4 categories as isolated intracranial hypertension, neurological deficits, encephalopathy and seizure. Symptoms related to increased intracranial hypertension are headache, diplopia, papilledema, sixth nerve palsy and decreased consciousness; focal neurological deficits present as motor and sensory impairments, aphasia. Though in 90% of patients with CVT , headache is the most common symptom, followed by seizures in 40% patients and 20 % patients with seizure.
Superior sagittal<unk>  is the most commonly involved<unk>  approximately 62% of patients and transverse<unk>  is the next common site (40-45%). Internal<unk>  vein and straight<unk>  are less commonly involved in CVT but associated with worse outcomes. Diagnosis of CVT is based on clinical findings and neuroimaging. D-dimer level is more than 500 μg/L in most of the patients with CVT. Per recommendation of American Heart Association (AMA) and the European Federation of Neurological Societies (EFNS), MRI/MRV is preferred 
for brain imaging. But CT can be considered if MRI is unavailable. Treatment of CVT includes early initiation of anticoagulant therapy and treatment of other underlying causes as sepsis, dehydration, discontinuation of prothrombotic medications; seizure and intracranial hypertension management.
CVT has good prognosis in 75% of patients with full functional recovery while in 15% of patients die or become dependent. Male sex, older age, confusion or coma, intracranial hemorrhage, deep vein involvement, infection and malignancy are the risk factors for poor outcomes.
Cerebral venous sinus thrombosis
Brain abscess
Cavernous sinus thrombosis
Subdural empyema
Arachnoiditis
Meningism
Meninges
Subarachnoid hemorrhage