neurologic examination. head neck & forelimbs trunk & hindlinbs tail & anus gait &...

Neurologic Examination

Neurologic Examination

HeadNeck & forelimbsTrunk & hindlinbsTail & anusGait & postureAncillary aids

Cranial nervesSlap 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

* 7 year old riding gelding* abrupt onset ataxia* weakness * urinary incontinence

VIDEO CASE 1

VIDEO CASE 1© 2003 Joe Mayhew

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CSF

EHV-1 Myeloencephalopathy

* 8 year old pregnant mare* sudden onset of signs* swelling at level of axis

VIDEO CASE 2

VIDEO CASE 2© 2003 Joe Mayhew

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Cervical radiographs

* yearling TB gelding* 1 month progressive ataxia

VIDEO CASE 3

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

* 4 year old Arabian gelding* 12 weeks progressive ataxia

VIDEO CASE 4

VIDEO CASE 4 © 2003 Joe Mayhew

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Cervical radiographs

Type II CVM“static compression”

• older patients

• proliferative osteoarthritis

• caudal neck

• malformed pedicles and arch

Type II CVM

• trauma?

• osteochondrosis?

• both?

* adult riding gelding * abrupt onset of unsteadiness/ataxia * muscle tremors

VIDEO CASE 5

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

* 6 month old Eriskay pony * 3 months progressive ataxia

VIDEO CASE 6

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 65

Anorexia 57

Weakness 94

Ataxia 72

Abnormal Mentation 67

Fasciculations 61

Cranial Nerve Deficits 44

Teeth Grinding 20

Ptyalism 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