The anatomical basis of venographic filling defects of the transverse sinus

Abstract

Obstruction of the intracranial dural venous sinuses would result in an increase in intracranial dural venous pressure. This intracranial hypertension is not only the result of poor cerebral venous drainage, but is also life threatening. The aim of this study was to identify the structures which may show signs of potential venographic filling defect qualities, including trabeculae/septa (also described as “fibrous bands”) and arachnoid granulations, which ultimately can lead to increased intracranial dural sinus venous pressure. A sample size of 102, consisting of cadavers and living patients, was used. Fifty-three percent of the subjects presented with structures in their transverse sinuses that could be potential venous filling defects. Thirty percent of the subjects presented with arachnoid granulations in the right transverse sinus, which were found to be significantly dominant (Chi-square; p<0.05). The study also revealed the presence of 1 to 5 septa in 29.4% of the subjects. The septa were found to be more dominant in the central (30%) and lateral (22%) thirds of the right transverse sinuses, while the central third of the left transverse sinus proved to be the least dominant occurring site (8%). In general, the right transverse sinus is highly more significantly dominant in septal occurrence (Chi-square; p<0.01) than observed in the left transverse sinus. The venographic filling defects showed good correlation between sexes (Pearson coefficient = 0.880) and different population groups (Pearson coefficient = 0.844). However, the filling defects appear not to be significantly different when compared between sexes and different population groups (Chi-square, p>0.05). We conclude from the statistical evidence that the right transverse sinus demonstrates significantly more potential venographic filling defects and submit that this information may assist in treatment options for patients diagnosed with idiopathic intracranial hypertension, as well as direct future research.