BMC Veterinary Research 2012, 8:215 doi:10.1186/1746-6148-8-215
Published: 8 November 2012
RVC = Royal Veterinary College
AHT = Animal Health Trust
SLVH = Stone Lion Veterinary Hospital,
Goddards Gp.
Background
Chiari-like malformation (CM) and syringomyelia is a neurological disease complex
with high prevalence in cavalier King Charles spaniels (CKCS). The natural progression
of this disease with time has not been described. The objectives of this study were
to i) determine if syringomyelia progresses with time ii) determine if features of
craniocrebral morphology previously associated with CM are progressive (including
caudal cranial fossa volume, caudal cranial fossa parenchymal volume, ventricular
dimensions, height of the foramen magnum and degree of cerebellar herniation). A retrospective
morphometric analysis was undertaken in 12 CKCS with CM for which repeat magnetic
resonance images were available without surgical intervention.
Results
The maximal syrinx width, height of the foramen magnum, length of cerebellar herniation
and caudal cranial fossa volume increased over time. Ventricular and caudal fossa
parenchymal volumes were not significantly different between scans.
Conclusions
The results of this study suggest that syringomyelia progresses with time. Increased
caudal cranial fossa volume may be associated with active resorption of the supraoccipital
bone, which has previously been found in histology specimens from adult CKCS. We hypothesise
that active resorption of the supraoccipital bone occurs due to pressure from the
cerebellum. These findings have important implications for our understanding of the
pathogenesis and variable natural clinical progression of CM and syringomyelia in
CKCS.
