Neurology

• The autonomic nervous system = parasympathetic and sympathetic.

  • Sympathetic only comes out of the lumbar region
  • Parasympathetic - cranial and sacral
  • The main outflow is the vagus (thorax and cranial abdomen)
• label the function of the cranial nerves

  A) smell

  B) vision

  C) movements

  D) sensation

  E) movement

  F) swallowing

  
• Right sided head tilt indicates a vestibular problem on the right hand side.
• • Cerebellum = fine motor control
  • Forebrain = consciousness and behaviour
  • Brain stem = autonomic control of the vital functions of life e.g., breathing
• In the fore brain, there is a voluntary control of movement. This inforation goes own the spinal cord and peripheral nerves to allow movement of limbs. There are two ways to do this, fast and slow. These both have a common pathway, the LMN. The LMN are found down the spinal cord which come out with the peripheral nerves. Damage along this pathway causes paralysis. The LMN have local reflexes which maintain tone, hence damage here will cause a loss of tone (flaccid paralysis with no reflexes). In comparison, if UMN you get a spastic paralysis as tone and reflexes are maintained via the LMN.
• There are two (glial) cells in the nervous cells which can die, undergo dysfunction, inflammation or proliferative while neurones are functional so can either function, not function or die.

  • The nerve cells do not get tumours as they do not proliferate
• steroids are contraindicated in acute spinal trauma
• discopondylitis is treated with antibiotics
• concussion IVDD is where there is a painful swelling, this requires conservative management and NSAIDs
• a compressive lesion with IVDD requires surgery
• FCE = fibrocartilaginous embolism
• FCE is treated conservatively (rest and physiotherapy) this is often non-painful so analgesia may not be needed
• which is more likely to cause unilateral signs IVDD or fibrocartilaginous embolism?

  FCE
• neospora causes myositis in the quadriceps muscles
• Dogs typically do not show signs of neospora infections but signs may be seen in some puppies and adult dogs. Most severe infections occur in young puppies, typically developing partial paralysis of the legs, particularly the hind legs. The paralysis is often progressive and results in rigid contracture of the muscles. The outlook for these puppies is poor.
• In adult dogs, neospora causes neurologic signs (such as inflammation of the brain and spinal cord), skin inflammation with sores, inflammation of the liver, pneumonia, and inflammation of the heart may occur. The outlook worsens in dogs with severe signs or not treated promptly.
• how do you treat neospora?

  clindamycin
• what treatment is for MUO?

  immunosuppressive corticosteroid dose
• discospondylitis is very painful and often has pyrexia
• SRMA (steroid responsive meningoarteritis) is unlikely to be painful or present with paresis
• what is the diagnosis?

  atlantoaxial subluxation

  
• when is SRMA most common?

  12 months
• when can MUO occur?

  any age
• neutrophilia on CSF is indicative of what?

  SRMA
• monocytes or mixed results on CSF indicate what?

  MUO
• IPRN (idiopathic polyradiculoneuritis) is a diagnosis of exclusion. This is self-limiting and can be treated with conservative management. Bladder control is maintained but they lose muscle dramatically. These need to be carried and supported to go to the toilet
• MUO = meningoencephalitis
• localise the lesion

  left sided central vestibular and forebrain

  
• MUO is a slowly progressive multi-focal disease
• is phenobarbitone is at the top end of the range and seizures are still present what would you add?

  potassium bromide
• circling can be a vestibular or forebrain lesion. to differentiate look for a head tilt as this will indicate vestibular
• there is circling to the left with no head tilt. where is the lesion?

  left forebrain
• are there any licensed anti-convulsants in cats?

  no but diazepam can be used long term
• opisthotonos = abnormal posturing or a severe form of muscle spasm
• if a dog is seizing give diazepam as it has a shorter half-life than phenobarbitone. if they continue to seize you can give propofol (intubate if a gag reflex has gone). this can also be supplemented with IV phenobarbitone which takes 20 minuets to have an effect.
• status epilectus = continuous seizing
• Opisthotonos indicates a dysfunction in the brain stem or meninges which is commonly caused by…

  • Meningitis
  • Encephalitis
  • Clostridium tetani infection (tetanus)
  • Intracranial haemorrhage or stroke
  • Traumatic brain injury
  • Neurotoxin exposure
  • Epilepsy (genetic predisposition)
  • Steroid responsive meningoarteritis(SRMA)
• Idiopathic head bobbing/nodding/tremors are common in bulldogs, this is a movement disorder, not a seizure. It is a diagnosis of exclusion and is benign so no treatment is needed.

  • Some owners say they can shorten episodes by distracting the dog.

  In these cases you need to rule out epilepsy, toxin exposure (identified via history) and metabolic disorders (biochemistry)if uncertain from the video footage. The giveaway is the normal mentation and is distracted out of the episode
• localise the lesion and name the damaged cranial nerves

  right sided peripheral vestibular lesion. damage to the facial and vestibulocochlear nerves

  
• which cranial nerve has been damaged?

  trigeminal