Neurology Flashcards
What is decerebrate rigidity and where is the lesion
Extension of all limbs and opisthotonus
Lesion rostral brainstem
Usually stuporous or comatose
What is decerebellate rigidity and where is the lesion
Hyper extension of TLs and opisthotonus
Lesion: rostral part of cerebellum
Mentation normal
May be episodic or postural
What is schiff-Sherrington and where is the lesion
Is it prognostic
Hyperextension of thoracic limbs and paralysis of pelvic limbs
Lesion: thoracic or cranial lumbar spine
Not prognostic
Ataxia - where could the lesion be
Spinal or peripheral nerve
Vestibular
Cerebellar
Grading of spinal lesions
Grade 1 - no deficits Grade 2 - paresis, ambulatory Grade 3 - paresis, non-ambulatory Grade 4 - paralysis Grade 5 - no pain sensation
Postural reactions
Paw position Hopping Hip sway Wheelbarrow Extensor postural thrust Placing responses
Cutaneous trunci where is the lesion
Wherever reflex stops between t3-l3 or if unilaterally absent there is a severe brachial plexus lesion
Horners syndrome lesion
Sympathetic supply to eye
Midbrain- cervical spinal cord - brachial plexus(t1-t3) - tympanic bulla - eye
What does the patellar reflex assess?
L4-s6 spinal segments and the femoral nerve
Menace response tests what?
Afferent
Efferent
Afferent: Retina Optic nerve Contralateral optic tract Contralateral forebrain
Efferent:
Contralateral forebrain
Ipsilateral cerebellum
Facial nerve (brainstem)
Problems seen with forebrain disease
Altered mental status (disorientation, depression)
Contralateral blindness (reduced menace but normal PLR)
Normal gait
Circling (ipsilateral, head turn, head pressing, pacing)
Decreased postural responses and proprioception in contralateral limbs
Seizures
Hemineglect syndrome
Behavioural change
Problems seen with brainstem lesions
Cranial nerve deficits (III-XII) Depression/stupor/coma Paresis of all or ipsilateral limbs Possible vestibular signs Possible decerebrate rigidity Decreased postural response in ipsilateral or all limbs Respiratory / cardiac abnormalities
Problems seen with cerebellar lesions
Normal mentation Ipsilateral menace deficit with normal vision Possible vestibular signs Possible decerebellate rigidity Intention tremors Wide based stance Truncal ataxia Hypermetria (can only be cerebellar) Proprioceptive deficits ipsilateral limbs
Vestibular nystagmus which direction is the lesion in relation to head tilt and nystagmus
Head tilt towards lesion
Fast phase away from lesion
Problems seen with myopathies
Generalised weakness and or exercise intolerance (stiff stilted gait,neck ventroflexion)
No proprioceptive deficits
Usually normal spinal reflexes unless significant muscle atrophy
Variable muscle tone and bulk
If menace and plr are absent where is the lesion
Either within the eye eg retina, Bilateral optic nerves or optic chiasm
Which nerve is required for extensor tone (and ability to bear weight) in the forelimb and hindlimbs
Forelimb- radial
Hindlimb - femoral and tibial
What is seen on MRI in cats with FIP
Periventriculitis
What is seen in CSF with cats with FIP
Increased protein (50-350 mg/dl) with a pleocytosis consisting neutrophils, lymphocytes and macrophages
How to diagnose masticatory myositis
Raised level of 2M antibodies that are specific for this condition
Diagnosis of myositis
Myalgia and muscle atrophy
High creatinine kinase levels 2000-3000
Electrodiagnostic tests and muscle biopsy revealing inflammatory cell infiltration (macrophages and lymphocytes)
Contraindications to CSF sampling
Increased ICP
Clotting problems
Chiari-like malformations
AA instability or trauma
Normal CSF characteristics
< 5 WBC/ul
No RBCs
Protein < 30-45mg/dl
What are spinal reflexes like with myopathies?
What about proprioceptive deficits?
Normal
No deficits (unless extremely weak and unable to move limbs - otherwise neuro exam should be normal)
Treatment of acute polyradiculoneuritis
Physiotherapist
Supportive care
Prognosis fair but if respiratory Ryan function it is poor
Recovery to ambulatory over several weeks
Clinical signs of acute polyradiculoneuritis
Acute and rapidly progressive
PLs affected over 2-3D then progresses to TLs
Non-ambulatory tetraparesis (may affect respiratory muscles)
Mental status unaffected
No autonomic signs
Diagnose of myopathy
EMG first followed by NCV to test peripheral nerve function as EMG cannot differentiate myopathy from neuropathy
Muscle and/or nerve biopsies
CSF analysis (polyradiculoneuritis)
Advanced imaging with some myopathies
Consequences of a tail pull injury
Urinary incontinence (retention)
Paralysis of tail
Faecal incontinence and loss of anal tone
A hyperextended hock is typical of damage to what nerve
Sciatic
A flaccid dropped tail is typical of damage to what nerve?
Caudal/coccygeal nerve
How to test pudendal nerve function
Perineal reflex
Prognostic indicators in cats with CNS lymphoma
Cats with paresis and FeLV infection are considered to have a poor prognosis
Difference between SRMA and MUO on CSF analysis
SRMA has a neutrophilic pleocytosis and MUO has a mononuclear pleocytosis or no changes
Antibiotic choice for discospondylitis
Beta- lactam and a flouroquinolone but ideally based on culture results (CSF, blood or urine)
Treat for 6-8 weeks
Sites of CSF collection
Cisterna magna or l5-l6 in dogs l6/7 in cats
