From Biovision’s Views Newsletter, Issue 2, May 2015
Vet: Barrie D. Grant, DVM, MS, DACVS, MRCVS
Affiliation: Barrie Grant Equine Consultant
Position: Consultant in private practice
Location: Bonsall, CA
Use: Currently performing clinical research into the feasibility and safety of implanting mesenchymal stem cells underneath the pia mater using the NeedleView® scope with a ventral cervical intervertebral approach between C3-C4 and C4-C5 in healthy horses
I first became aware of Biovision when they exhibited at the American College of Veterinary Surgeons (ACVS) Surgery Summit in Chicago in 2011. I had been looking for an approach to image the spinal cord that was not too invasive. I talked to John [Small, Biovision’s president] as well as to other vets. Soon after that, I went to South Africa and encountered Dr. Olivier Lepage, who was on sabbatical from the University of Lyon. He was looking for a project but had no funding. When I got back home, I connected with Dr. Elaine Carpenter at Cave Creek Equine Surgical and Diagnostic Imaging Center in Phoenix, AZ. She has assisted me in the past with spinal surgeries, and Cave Creek has been using Biovision’s NeedleView® Arthroscope Suite since early 2012. Cave Creek soon had a case; they got great video and we were able to share it with Dr. Lepage. Not long thereafter, one of his students received approval for a research proposal using the NeedleView®. We have recently completed the first phase of that 6-month study (undertaken with Olivier Lepage, DMV, MSc, PhD, HDR, DipECVS of the University of Lyon and his student Isé B. François, DMV, in Marcy L’Etoile, France).
Cervical stenotic myelopathy (wobbler syndrome) is a common cause of spinal ataxia in young horses. This developmental disorder is characterized by postnatal deformation of the cervical vertebrae, resulting in stenosis of the vertebral canal and spinal cord compression. Dysfunction of the equine cervical cord can result in a wide spectrum of clinical signs ranging from total paresis to poor performance as a result of the neuropraxia and discomfort in proprioception. The diagnosis is based on history, clinical signs, radiographic changes, myelography, and cerebrospinal fluid analysis. Presently, the treatment of wobbler horses is based on the principle of eliminating cervical cord compression by the surgical stabilization of the intervertebral space with a threaded titanium implant (Seattle Slew implant).
It seemed possible that the open approach used for the stabilization surgery would permit successful insertion of a 25-gauge catheter into the subarachnoid space. Then the NeedleView® scope was inserted through this catheter and the spinal cord visualized for signs of myelographic compression. The objectives of the study are to describe the ventral intercervical approach for endoscopy assessment of the cervical canal and to evaluate the safety and innocuousness of the implantation of mesenchymal stem cells underneath the pia mater. Stem cell transplantation has shown benefit in canines with spinal cord injury and in humans with amyotrophic lateral sclerosis (ALS); we believe direct transplantation of mesenchymal stem cells into the cervical canal may improve the postoperative success of the surgery and reduce the convalescence time of horses with cervical stenotic myelopathy. Our clinical experimentation took place in late February and early March 2015. Our schedule calls for two months for statistical analysis and another three months for writing up the results and the article.
Key benefit(s) of the NeedleView® modality: The scope’s small size will make it possible to put it directly into the spinal cord, allowing the direct placement of stem cells.