Neurologic Examination
Neurologic Examination
Head
Neck & forelimbs
Trunk & hindlinbs
Tail & anus
Gait & posture
Ancillary aids
Cranial nerves
Slap test
TL reflex
Neck & forelimbs
Neck & forelimbs
Trunk & hindlinbs
Trunk & hindlinbs
Tail & anus
Gait & posture
Gait & posture
Ataxia
Gait & posture
Weakness
Gait & posture
Case History
• 12yo Cleveland Bay mare
• Sudden onset grade 4 ataxia and paraparesis
Neurologic Examination
© 2003 Joe Mayhew
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Lesion location
CSF
Possible cause?
Equine Ataxia
VIDEO CASE 1
* 7 year old riding gelding
* abrupt onset ataxia
* weakness
* urinary incontinence
VIDEO CASE 1
© 2003 Joe Mayhew
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CSF
EHV-1 Myeloencephalopathy
VIDEO CASE 2
* 8 year old pregnant mare
* sudden onset of signs
* swelling at level of axis
VIDEO CASE 2
© 2003 Joe Mayhew
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Cervical radiographs
VIDEO CASE 3
* yearling TB gelding
* 1 month progressive ataxia
VIDEO CASE 3
© 2003 Joe Mayhew
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Cervical radiographs
Type I CVM
“dynamic compression”
• mostly young patients
• formative vertebral changes - DOD
• vertebral canal stenosis
VIDEO CASE 4
* 4 year old Arabian gelding
* 12 weeks progressive ataxia
VIDEO CASE 4
© 2003 Joe Mayhew
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Cervical radiographs
Type II CVM
“static compression”
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•
•
•
older patients
proliferative osteoarthritis
caudal neck
malformed pedicles and arch
Type II CVM
• trauma?
• osteochondrosis?
• both?
VIDEO CASE 5
* adult riding gelding
* abrupt onset of unsteadiness/ataxia
* muscle tremors
VIDEO CASE 5
© 2003 Joe Mayhew
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Ryegrass Staggers
• Diffuse Spino-vestibulo-cerebellar
Syndrome
• hypometric ataxia
• little weakness
• muscle tremor
• muscle fasciculation
• ataxic eyeball movements
• ‘convulsive’ episodes
VIDEO CASE 6
* 6 month old Eriskay pony
* 3 months progressive ataxia
VIDEO CASE 6
© 2003 Joe Mayhew
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VIDEO CASE 6
VIDEO CASE 6
Cerebellar Degeneration [Abiotrophy]
Equine Protozoal Myeloencephalitis
EPM
• Sarcocystis neurona
• definitive host - North American opossum
• int. hosts – racoon, armadillo …..
• serum immunoblot test for antibodies
• CSF immunoblot test for antibodies
• CSF pcr for antigenic sequences
EPM
• Treatment
• sulfadiazine and pyrimethamine
• diclazuril, toltrazuril
• nitazoxanide
• Vaccine
West-Nile Virus Encephalomyelitis
Reservoir
Dead end hosts
West-Nile Virus Encephalomyelitis
Clinical Signs
Increased Body Temperature
Anorexia
Weakness
Ataxia
Abnormal Mentation
Fasciculations
Cranial Nerve Deficits
Teeth Grinding
Ptyalism
%
65
57
94
72
67
61
44
20
7
West-Nile Virus Encephalomyelitis
Diagnosis
• CSF – 70% abnormal
• Serology – IgM ELISA; 93% sensitivity
West-Nile Virus Encephalomyelitis
• 35% mortality
• Vaccination – at least twice yearly
• Remove stagnant water