Angiographic cerebral venous sinus calibers and drainage patterns in patients with normal intracranial pressure and idiopathic intracranial hypertension

Background: Normative venous sinus diameters are not well established. This study seeks to compare two-dimensional digital subtraction cerebral angiographic (DSA) venous sinus calibers for patients with normal intracranial pressure (ICP) and with idiopathic intracranial hypertension (IIH).

Methods: Patients who underwent diagnostic cerebral angiography from 2016 to 2020 were retrospectively identified. Two independent reviewers measured venous sinus calibers from anteroposterior (AP) and lateral carotid injection delayed venous phase in patients from two groups (group 1: patients with normal ICP; group 2: patients with IIH) after receiving training in a standardized measurement protocol, with measurements obtained from the superior sagittal sinus (SSS) through the sigmoid sinuses (SS).

Results: 97 patients from group 1 and 30 patients from group 2 were included. Interrater reliability was greater than 0.75 for all measured sites. Both groups had similar anatomical subtypes with most being right transverse sinus (TS) dominant or codominant. In group 1, men had significantly larger SSS on lateral view (p<0.001) and dominant TS calibers on AP view (p=0.02) compared with women. Both dominant TS measurements and SSS measurements (lateral plane) were significantly smaller among group 2 compared with group 1 (p<0.001 and 0.02, respectively). Patients with IIH had significantly larger dominant SS measurements (p=0.01). Bifid SSS anatomy was present in 9% of patients with mean caudal width 31 mm (range 19-49 mm).

Conclusions: This study is the first to provide two-dimensional DSA dural venous sinus calibers in patients with and without IIH and to compare anatomical drainage types and calibers among groups.