What are congenital lesions?
Fluid on the brain
What are the symptoms of congenital lesions?
- Excess vocalization
- Hyperexcitability
- Blindness
- Seizures
- A large dome-shaped head (due to intracranial swelling)
- Strabismus (wall eye)
- Nystagmus (increases eye movement)
- Gait abnormalities
- Coma
- Abnormal breathing
- Opisthotonus - Animal may arch its head back and extend all four legs
What are the two types of epilepsy?
- Idiopathic Epilepsy- there is no known cause for the condition and it is assumed it may be an inherited condition.
- Secondary Epilepsy - This diagnosis is used when a specific cause for the seizures can be found.
What are seizures?
- An epileptic seizure is the clinical manifestation of abnormal brain activity in the cerebral cortex
- These abnormalities can create seizures that vary from the mild “petit mal” to the generalized, full body “grand mal.”
What is atlantoaxial subluxation?
- Relationship between C1 and C2 is maintained by ligaments
- Toy breeds, congenital
- Deformity or absence of C2
- Can also be traumatic origin if ligaments damaged
- Leads to misalignment and subsequent spinal cord compression
- Neck pain. Neuro signs vary – ataxia, proprioceptive deficits, tetrapariesis
What can congenital lesions do to the spine?
- Malformation of the spine
- Kyphosis
- Scoliosis
- Lordosis
- Often neurological
- Butterfly vertebrae
- Dorsal to ventral cleft
- Hemivertebrae
- Wedge-shaped
- Block vertebrae
- Fused ventral bodies
What is the congenital lesion, Syringomyelia?
•Breed specific – Cavalier King Charles Spaniel
•Hereditable
•Dilation in the centre of the cervical spine
•Apparent itching and scratching of face and ears
•Possibly holds head to one side
•Surgical placement of draining
•Differential diagnoses:
–Secretory otitis media, middle ear infection
–Disc extrusion
- can be confused with an ear infection as they hold their head to the side
What is trauma?
Brain injury
•Haemorrhage
•Brain swelling
•Coup/contracoup
Spinal cord injury •Usually cervical •Proprioceptive deficit •Degree of trauma •Site of damage •Sudden onset ataxia •Reluctance to move •Recumbency •Stiff painful neck •Sweating •Spinal cord ischaemia = 2y injury
What are cervical vertebral stenotic myelopathy- Wobblers?
- Cervical vertebral instability
- Movement of vertebrae put pressure on spine
- Breed predisposition (Dobermans, Great Danes, Dalmations)
- Wide based stance
- Progressive ataxia
- Neck pain
- Low head carriage
- Paresis to paralysis at end stage
What is rabies?- inflammatory/ infectious conditions
- Zoonosis
- Transmission via bite
- Transported via neuronal axons to CNS
- Spinal cord most commonly affected
- Ataxia, hind limb paresis
- Loss of tail and anal sphincter tone
- Vaccination
What is tetanus?- inflammatory/ infectious conditions
- Clostridium tetani - bacteria
- Common soil organism (spores)
- Deep penetrating wounds
Produces 3 potent biological neurotoxins
•Tetanospasmin
•Haemolysin
•Peripheral acting non spasmogenic toxin
•Neurotoxins affect signals at the nerve synapses
Symptoms
•Lock jaw
•Recumbence
•Muscle spasms
What is Invertebral disc disease?- degenerative conditions
•Intervertebral disc – cartilage acting as shock absorbers •Held in place by ligament •Disc prolapse •Pressure on spine •Neurological signs •Breed predisposition – chondrodystrophic breeds (Dachshund, Basset Hound) •Acute – Hansen type one –Sudden neurological deficit –Severe pain –Calcified nucleus of disc –More in cervical vertebra
•Chronic – Hansen type two –Progressively worse back pain –Progressive neurological deficit –More in thoraco-lumbar vertebrae •Radiographs, myelogram, MRI •Conservative treatment •Surgery
What is ancylosing spondylosis?- degenerative conditions
- Back pain
- Osteophyte formation of vertebrae
- Can be incidental finding
- Painful while forming
- Can fuse part of spine
- Possible neurological signs
- Radiographs
- Anti-inflammatories
- Acupuncture
What is fibre-cartilaginous infarct?- degenerative conditions
- Fibrocartilaginous embolism in dogs is caused by a small fragment of intervertebral disk material that migrates into the blood vessels of the spinal cord. This blocks off the blood supply to the spinal cord
- Any breed
- No pain
- Acute neurological symptoms
- Nothing visible on radiographs
What is intervertebral disk disease?- degenerative conditions
- Degeneration of the intervertebral disks
- Partial or complete prolapse
- Neck pain
- Neurological signs
- Anti-inflammatories
- Strict rest
- Surgery
What is discospondylitis?- degenerative conditions
- Infection of vertebrae
- Very painful
- Lumbo-sacral joint most common
What is chronic degenerative radiculomyelopathy?- degenerative conditions
- CDRM
- German shepards
- Progressive degeneration of caudal spinal cord
- Progressive loss of nerve innervation to hind legs
- Ataxia
- Lack of proprioception
- Not painful
- Possible incontinence
- Nothing visible on radiographs
- No effective treatment
What is cauda-equina syndrome?- degenerative conditions
- Lumbo-sacral joint – pivot point
- Spine vulnerable here
- Instability of joint – pinching of nerves
- Spinal canal too narrow – pressure on spinal cord
- Very painful
- Neurological symptoms
- Radiographs, myelogram, MRI
- Anti-inflammatories
- Acupuncture
- Possible surgery
- Large and giant breeds, esp GSD
What is vestibular disease?
- 2 forms
- Peripheral
- Central
- Has an effect on the balance of the dog
- Caused by irritation of the nerves
- Causes can be from
- inflammatory disease, infection, trauma or bleeding in the brain, loss of blood flow, and cancer.
What is horners syndroms?
- Horner’s syndrome is a common neurological disorder of the eye and facial muscles.
- The condition usually occurs suddenly. The most common clinical signs of Horner’s syndrome are:
- Drooping of the eyelids on the affected side (ptosis)
- The pupil of the affected eye will be constricted (miosis)
- The affected eye often appears sunken (enophthalmos)
- The third eyelid of the affected eye may appear red and raised (prolapse of the third eyelid, conjunctival hyperemia)
- Horner’s syndrome is due to a dysfunction of the nerves of the eyes and surrounding facial muscles. It can also occur secondry to injury to the brachial plexus
What is neoplasia?
- Osteosarcomas
- Lymphoma
- Meningioma
- Mast cell tumour
- Metastasis
- Haemangiosarcoma
- Neurological signs
- Anti-inflammatories
