19^th April 2012

RVC researchers, including Dr. Imelda McGonnell and Dr. Holger Volk, have recently published some novel and interesting findings addressing the important unanswered questions underlying the pathogenesis of Chiari malformation (CM) in Cavalier King Charles Spaniels (CKCS) in PLoS ONE.

CM is a common developmental defect that affects both humans and canines. The prevalence of CM is estimated to be ~0.1% in humans and >95% in CKCS. In this syndrome, mismatching of the volume of the occipital skull and the hindbrain results in compression and herniation of the cerebellum, which changes the cerebrospinal fluid flow dynamics resulting in syrinx formation in the spinal cord (syringomyelia [SM]). CM and CM/SM can cause pain and significant neurological dysfunction in both species. Treatment is currently limited to surgical intervention and is often unsuccessful. There remains a lack of animal models to study CM.

Thomas Shaw, who did this research project during his veterinary studies, said: "Our results show that the CKCS has a relatively larger cerebellum than small breed dogs and Labradors and provide evidence that increased cerebellar volume in CKCS is associated with crowding of cerebellum in the caudal part of the caudal cranial fossa. In CKCS there is an association between increased cerebellar volume and SM. These findings have implications for the understanding of the pathological mechanisms of CM/SM, and support the hypothesis that it is a multifactorial disease process governed by increased cerebellar volume and failure of the skull to reach a commensurate size". Dr. McGonnell and Dr. Volk added: "In light of these findings, we will now investigate cerebellar development in various chicken, dogs and mouse models." We hope that this research will lead to a better understanding of the disease process and provide therapeutic targets." This project is jointly undertaken in the laboratories of Drs’ Imelda McGonnell and Holger Volk at the Royal Veterinary College and Dr Albert Basson in the Dept Craniofacial Development, Kings College London, funded by the Wellcome Trust.

Shaw TA, McGonnell IM, Driver CJ, Rusbridge C, Volk HA (2012) Increase in Cerebellar Volume in Cavalier King Charles Spaniels with Chiari-like Malformation and Its Role in the Development of Syringomyelia. PloS one 7: e33660.

Read the full article at http://dx.plos.org/10.1371/journal.pone.0033660

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