Many of these were elderly and had neurological symptoms in the period leading up to their death, and many developed concomitant heart failure. An estimated 0.3% incidence of CVST in patients infected with SARS-CoV-2.In children, a Canadian study reported in 2001 that CVST occurs in 6.7 per million annually. 43% occur in the newborn (less than one month old), and a further 10% in the first year of life. Of the newborn, 84% were already ill, mostly from complications after childbirth and dehydration. History
The first description of thrombosis of the cerebral veins and sinuses is attributed to the French physician Ribes, who in 1825 observed thrombosis of the sagittal sinus and cerebral veins in a man who had had seizures and delirium. Until the second half of the 20th century it remained a diagnosis generally made after death. In the 1940s, reports by Dr Charles Symonds and others allowed for the clinical diagnosis of cerebral venous thrombosis, using characteristic signs and symptoms and results of lumbar puncture.Improvements on the diagnosis of cerebral venous sinus thrombosis in life were made with the introduction of venography in 1951, which also aided in the distinction from idiopathic intracranial hypertension, which has similar presenting signs and symptoms in many cases.The British gynecologist Stansfield is credited with the introduction, in 1942, of the just recently introduced anticoagulant heparin in the treatment of CVST in 1942. Clinical trials in the 1990s finally resolved the concern about using anticoagulants in most cases of CVST.
Cerebral edema and venous infarction may be apparent on any modality, but for the detection of the thrombus itself, the most commonly used tests are computed tomography (CT) and magnetic resonance imaging (MRI), both using various types of radiocontrast to perform a venogram and visualise the veins around the brain.Computed tomography, with radiocontrast in the venous phase (CT venography or CTV), has a detection rate that in some regards exceeds that of MRI. The test involves injection into a vein (usually in the arm) of a radioopaque substance, and time is allowed for the bloodstream to carry it to the cerebral veins – at which point the scan is performed. It has a sensitivity of 75–100% (it detects 75–100% of all clots present), and a specificity of 81–100% (it would be incorrectly positive in 0–19%). In the first two weeks, the "empty delta sign" may be observed (in later stages, this sign may disappear). The empty delta sign is characterized by enhancement of the dural wall without intra-sinus enhancement.Magnetic resonance venography employs the same principles, but uses MRI as a scanning modality. MRI has the advantage of being better at detecting damage to the brain itself as a result of the increased pressure on the obstructed veins, but it is not readily available in many hospitals and the interpretation may be difficult.Cerebral angiography may demonstrate smaller clots than CT or MRI, and obstructed veins may give the "corkscrew appearance".