Ventral Spinal Cord Displacement: A Guide to Differentiating Spinal Cord Herniation From Dorsal Arachnoid Web With...

Spinal arachnoid webs (SAW) are abnormally thickened arachnoid membrane within the subarachnoid space that can tether and compress the cord and spinal cord herniation (SCH) results when there is displacement of the spinal cord through an opening of the dura or arachnoid mater. They have similar clinical presentations secondary to spinal cord compression, and both appear as focal anterior displacement of the spinal cord on MRI, making them difficult to differentiate from one another. However, operative technique for management differs significantly. The goal of this article was to review imaging characteristics of SAW and SCH with guidance on how to best differentiate the 2 during preoperative workup. We also aim to review nuances of operative technique for both pathologies.

We outline the presentation of SAW and SCH through 2 clinical cases, focusing on details of imaging characteristics and operative techniques using novel illustrations and animations in combination with 2D operative videos. We also reviewed existing literature comparing the radiographic differences between the 2 pathologies.

We provide illustrative case presentations with narrated 2-dimensional operative videos to discuss in detail the nuanced imaging findings and intraoperative techniques required for management SAW and SCH to improve surgeon's ability to differentiate between the 2 and effectively manage both pathologies.

SAW and SCH can be difficult to differentiate and require very different strategies for operative management. These cases and operative videos provide a valuable resource for successfully managing both.