Detailed Anatomy of Bridging Veins Around the Foramen Magnum: a Multicenter Study Using Three-dimensional Angiography

Area of Science:

• Neuroanatomy
• Vascular Imaging
• Neurosurgery

Background:

• Limited literature exists on the bridging veins (BVs) of the medulla oblongata near the foramen magnum (FM).
• Understanding the normal angioarchitecture of these BVs is crucial for surgical planning and interpreting pathologies.

Purpose of the Study:

• To analyze the normal angioarchitecture of bridging veins (BVs) around the foramen magnum (FM).
• To characterize the course, drainage outlets, and prevalence of BVs using three-dimensional (3D) angiography.

Main Methods:

• Collected and analyzed 3D angiography data of posterior fossa veins.
• Examined the course, outlet, number, detection rate, and mean diameter of BVs around the FM using slab maximum intensity projection (MIP) images.

Main Results:

• Bridging veins (BVs) were detected in 96% of 57 patients, with a median of two BVs per patient.
• BVs drain into anterior condylar veins, inferior petrosal sinus, sigmoid sinus, jugular bulb, suboccipital cavernous sinus, marginal sinus, and occipital sinus.
• Five subtypes of BVs were classified based on drainage: anterior condylar vein (ACV), jugular foramen (JF), marginal sinus (MS), suboccipital cavernous sinus (SCS), and cerebellomedullary cistern (CMC).

Conclusions:

• Bridging veins (BVs) around the foramen magnum (FM) are consistently present and exhibit diverse drainage patterns.
• Three-dimensional angiography provides detailed insights into the angioarchitecture of FM BVs.