Abstract #2569

Dipolar Anisotropy Fiber Imaging of Human Anulus Fibrosus

Won C. Bae¹, Sheronda Statum¹, Richard Znamirowski¹, Koichi Masuda², Graeme M. Bydder¹, Nikolaus M. Szeverenyi¹

¹Radiology, University of California, San Diego, San Diego, CA, United States; ²Orthopaedic Surgery, University of California, San Diego, La Jolla, CA, United States

Anulus fibrosus (AF) forms concentric fibrous lamellae in the periphery of the intervertebral disc. AF is disrupted structurally during disc herniation and degeneration, but is not routinely visualized with clinical MR imaging. In this study, a degenerate human disc specimen was imaged using 3D FSPGR in six orientations, co-registered, and image-processed to visualize detailed fiber structure of the AF. Classic lamellar patterns of the AF, only previously observed with light microscopy, were observed, along with signs of degeneration such as thickening and inverse bulging of the lamellae. This technique can be implemented in vertical magnets for clinical use.