The symposium is co-organised by The Ann Conroy Trust, in association with Aesculap Academia.
The Ann Conroy Trust is Registered Charity No: 1165808.
We provide Support, Education and Research for patients living with Chiari Malformation, Syringomyelia and associated conditions.
F30 Computer simulation of syringomyelia in brachycephalic dogs.
Cirovic S, Lloyd R, Rusbridge C.
Syringomyelia is a disorder associated with chronic pain, sensory loss, and paralysis. Since the pathogenesis remains unknown surgical interventions aimed at managing this condition have limited success. The most common cause of syringomyelia in humans is Chiari type I malformation and in animals the analogous condition is the Chiari-like malformation, to which some toy breed dogs are particularly predisposed. In cavalier King Charles spaniels up to 70% of dogs also develop Chiari-related syringomyelia. Such breeds thus represent a naturally occurring animal model to investigate the origins of syringomyelia. A finite element model of the canine spinal cavity has been developed to investigate the dynamics of spinal CSF compartment in normal and pathological conditions.
The model included the spinal cord (with or without the syrinx) and cerebrospinal fluid (CSF) in the subarachnoid space, the dura and the epidural space. These features were reconstructed from MR scans of a cavalier King Charles spaniels suffering from a large syrinx. The cranial CSF compartment was modelled as a lumped compartment obeying the Monro-Kellie doctrine. The model was excited at the cranium to simulate shift in the blood volume related to the cardiac cycle.
For normal conditions the stress in the spinal cord was low and uniformly distributed along its length. With a blockage between the cranial and spinal CSF spaces normal shear and axial stresses increased significantly at the regions in the cord where the syrinxes typically form. This elevated stress originated from the bending of the cord at the locations where its curvature was high.
The results suggest that repetitive stressing of the spinal cord, caused by its exaggerated movement, could be a cause for the initial formation of syrinx cavities. A more comprehensive model of cranial CSF compartment and consideration of factors such as cord tethering is needed.