Interobserver agreement in the magnetic resonance location of cerebral vein and dural sinus thrombosis

The interobserver variation in the magnetic resonance (MR) location of cerebral vein and dural sinus thrombosis (CVT) has not been previously reported. Four independent observers rated a convenience sample of 40 MR/MR angiographies to assess whether or not each dural sinus and major cerebral veins were occluded. Interobserver reliability was measured using κ statistics. Interobserver agreement was comparable between the six pairs of raters. Agreement was excellent for thrombosis of the deep cerebral venous system ( κ  = 1.00), cerebellar veins ( κ  = 1.00), superior saggital sinus ( κ range: 0.82–1) and right jugular vein ( κ range: 0.84–0.95); good to excellent for the right transverse/sigmoid sinus ( κ range: 0.75–0.90) and the left jugular vein ( κ range: 0.65–0.85); moderate to excellent for the left lateral sinus ( κ range: 0.59–0.78) and the straight sinus ( κ range: 0.59–0.92); poor to good for the cortical veins ( κ range: 0.02–0.65). Agreement between observers varies with the location of CVT. It is good or excellent for most of the occluded sinus and veins, except for the cortical veins. This study suggests that information on the location of CVT can be reliably collected and used in multicentre studies.