Neuro and Skull

What is the signalment for atlanto-axial subluxation?

Toy breed dogs less than 1 year old

What is the pathogenesis of atlanto-axial subluxation?

Dens agenesis/hypoplasia

Ligament agenesis

Dens fracture

Atlanto-axial subluxation

What are the radiographic findings of an atlanto-axial subluxation?

Caudodorsal angulation of C2

Increased interarcuate space

Small or absent dens

What can help you identify a small or absent dens in a atlanto-axial subluxation case?

Oblique lateral view or MILD flexed lateral view

When taking a radiograph for a atlanto-axial subluxation what do you need to be cautious with?

Neck flexion

Atanto-axial instability

Atlanto-axial instability due to no dens being present

How do you treat atlanto-axial instability?

Surgically to add pins and plates to stabilize

What are the degenerative spinal conditions?

Spondylosis

Spondyloarthrosis

Disc degeneration

What is spondylosis?

Degenerative disease of the spine

What happens during spondylosis?

Periarticular new bone ventral/lateral aspect of adjacent vertebral bodies

I/V foramina can be impinged

What is the degree of spondylosis?

Varies and can progress to fusion/bridging spondylosis

What is essentially degenerative joint disease around the vertebral joints?

Spondylosis

Describe primary spondylosis?

Not clinically significant unless it progresses to nerve root involvement

What does primary spondylosis at lumbosacral region indicate?

Cauda equina

What can spondylosis be secondary to?

Cervical vertebral instability (Wobblers)

IVDD

Discospondylitis

Trauma

Spondylosis

Spondylosis

What is spondylarthrosis?

DJD of articulation facets

What is the signalment for spondylarthrosis?

Older dogs

What can spondylarthrosis progress to?

Extend to involve the IVF or impinge on spinal cord

What can IVDD be?

Traumatic or degenerative

What animals get degenerative IVDD?

Young chondrodysplasia breeds and older other breeds

Why should you do for an IVDD neurological exam?

To neurolocalize

What is Hansen Type 1?

Extrusion

What is Hansen Type II?

Protrusion

Hansen Type 1 IVDD

Hansen Type II IVDD

What are the radiographic findings of IVDD?

Narrowing of the IV disc space

Narrowing of articular facet joint space

Small IV foramen

Increased opacity in intervertebral foramen or spinal cord

What is disc mineralization indiciative?

Degeneration

IVDD

What does a mineralized disc not indicate?

Disc herniation

IVDD

T/F anesthesia is necessary to critically evaluate disc spaces?

True

What dogs typically get lumbosacral disease?

Large breeds

What are the C/S of lumbosacral disease?

Pain on HQ extension/manipulation

Struggling to get up

Cadua equina

Fecal/urinary incontinence

How do you take a radiograph to diagnose lumbosacral disease?

Flexed, hyperextended, and neutral lateral radiographs

What are the radiographic findings of lumbosacral disease?

Narrowed LS space

End plate sclerosis

T/F LS spondylosis is often seen without C/S?

True

What are the two inflammatory conditions in the spine?

Discospondylitis

Spondylitis

What is discospondylitis?

Infection of the intervertebral discs and end plates

What are the common causes of discospondylitis?

Bacteria dn fungus

How do you diagnose discospondylitis?

Radiograph whole vertebral column and repeat every 2-3 weeks to monitor healing

Why can discospondylitis present at multiple sites?

The bacteria or fungus spreads hematogenously

What is the earliest sign of discospondylitis?

Decreased width of i/v disk space (will increase in width shortly after)

What happens during the early stage of discopsondylitis?

Increased width if i/v disc spaces a.r.o lysis of end plates

Sclerosis of adjacent vertebral bodies

What happens in the late stage of disconspondylitis?

Spondylosis

Lytic area fills up with bone causing fusion

What are some complications with discospondylitis?

Spinal cord compression

Empyema

Progression of diskospondylitis

What is spondylitis?

Inflammation/infection of the vertebral body

T/F spondylitis involves the vertebral disk

False

What are the causes of spondylitis?

Bacteria

Parasite

Foreign bodies (grass awn)

Metastatic neoplasia

What neoplasm usually causes spondylitis?

Prostate concer

What does spondylitis look like usually?

Ventral periosteal reaction

• Brushlike/spiculated

• Lamellar

• Solid

Spondylitis

What are the common indications for a skull radiograph?

Dentals, aural, nasal and frontal sinuses, TMJ, Trauma to skull, neoplastic condition

What doe skull radiology have limited value in?

Intracranial dz

What is the trick to taking skull radiographs?

Be perfectly symmetrical

What is the problem with acute aural injury on a radiograph?

There are no changes

What chronic changes in the ears can be seen w/ a radiogrpah?

Mineralization of ear canals

Narrowing of ear canals

Thickening of tympanic bulla

Lysis of tympanic bulla

What is happening and important

Mineralization of ear canals indicated chronic otitis externa

What is happening and importance?

Chronic otitis media with thickened bulla

What is happening and importance?

Chronic otitis media with thickened bulla

What are the causes of nasal disease?

Neoplasia

Infection

Foreign body

Idiopathic

What are the C/S of nasal disease?

Stertor/stridor

Nasal discharge

Facial deformity

Fungal rhinitis

Nasal adenocarcinoma

How do you eliminate superimposition of the mandible?

Put dog on its back

Shoot from above the mandible

Why are L3 and L4 more common to get migrating grass awns than other vertebra?

They are attached to the diaphragm

What happens to the ventral surface of the vertebral body with spondylitis?

It becomes flattened or convex due to periosteal reaction

What is the ventral surface of a normal vertebral body?

Concave

Fracture luxation

Fracture luxation

Compression fracture