Atlanto-Axial Luxation and Syringohydromyelia Flashcards
where is the axial ligament?
dorsal arches of atlas and axis
what does the apical ligament do?
connects dens to occipital condyles
what are some congenital malformations for atlanto-axial luxation?
aplasia of dens
hypoplasia of dens
absence of ligaments
which breeds usually have atlanto-axial luxation?
toy poodle
chihuahua
yorkshire terrier
pomeranian
shih tzu
dachshund
what should you not do when taking radiographs of an atlanto-axial luxation?
do not flex the neck
what is the prognosis of atlanto-axial luxation with medical treatment?
50% do well
what is done in surgical treatment of atlanto-axial luxation?
definitive re-alignment and decompression
ventral fusion and permanent biological fixation
what are the difficulties with surgical treatment of atlanto-axial luxation?
small dogs: difficult screw placement
young dogs: soft and immature bone
damage of large blood vessels
spinal cord trauma
what are the long term complications of atlanto-axial luxation?
implant failure
infection
dysphagia
what primary spinal cord disorder can cause syringohydromyelia?
spinal arachnoid cysts
what primary brain disorders can cause syringohydromyelia?
brain tumors
CSF overproduction by plexus papilloma
dermoid or epidermoid cyst
what are the diagnostic MRI findings with chiari-like malformation?
rostral displacement of cerebellum
cerebellar coning
kinked medulla
syringohydromeylia
ventricular enlargement
attenuation of subarachnoid space at cervico-medullary junction
where does CSF flow normally during diastole?
rostral
which breed is especially predisposed to chiari-like malformation?
cavalier king charles spaniel: autosomal recessive trait, incomplete penetrance
what correlates best with clinical signs in chiari-like malformation and syringohydromyelia?
maximal diameter of syrinx