Use of GDNF Releasing Nanofiber Nerve Guide Conduits for the Repair of Conus Medullaris/Cauda Equina Injury in the Nonhuman Primate
Abstract
The present study evaluated a surgical approach for repair of conus medullaris/cauda equina injury in rhesus macaques using a biodegradable bridging graft that releasing the trophic factor, GDNF. All subjects have been entered into the study. All subjects have also undergone pre-surgical testing, including magnetic resonance imaging, pain behavioral testing, urodynamic recordings, electromyography of external anal sphincter, and locomotor testing. All subjects have also undergone surgery with 5 subjects in each group undergoing either 1) unilateral L6-S3 ventral root avulsion (VRA) injury, 2) L6-S3 VRA injury followed by replantation into the spinal cord using a peripheral nerve bridging graft, 3) L6-S3 VRA injury followed by root replantation into the spinal cord using a GDNF-releasing nerve guide channel as bridging graft, or 4) L6-S3 VRA injury followed by root replantation into the spinal cord using an empty (control) nerve guide channel as bridging graft. The surgery was tolerated well and subjects have undergone additional, longitudinal functional assessments using locomotor training, urodynamic recordings, electromyography of the pelvic floor, and pain behavioral testing. At 18 months after the surgery, a final set of imaging and functional assessments were obtained, following by termination of the study and harvesting of spinal cord and nerve root tissues for anatomical studies. Collected materials and data are presently undergoing additional analysis and are being prepared for manuscript submissions. To summarize, subjects with either peripheral nerve bridging grafts or GDNF-releasing nerve guide channels have shown that axonal regeneration by myelinated fibers are capable of entering the graft and reinnervate the periphery.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 2015
- Accession Number
- AD1035975
Entities
People
- Kari Christe
- Leif A Havton
Organizations
- University of California, Irvine