Presentation Transcript
Slide1: New tilt on an old problem.
Cardinal Signs of V.D.: Cardinal Signs of V.D. Head Tilt
Nystagmus
Horizontal
Rotatory
Vertical
Positional
Circling (tight)
Imbalance & Incoordination
Nystagmus: Nystagmus Horizontal
Fast-Phase away from head tilt
Fast Phase toward head tilt
Rotatory
Vertical
Positional Peripheral V.D.
Central V.D.
Vestibular Diseases: Vestibular Diseases Vestibular Disease Idiopathic V.D. Inner Ear Disease Central V.D. 8th Nerve only 8th Nerve,
7th Nerve &
Horner’s Syndrome Anything Else
Idiopathic V.D.: Idiopathic V.D. Acute Onset of Vestibular Signs
Head tilt
Horizontal or Rotatory nystagmus with fast-phase away from head tilt
Nothing else
Can Be Very Severe
Idiopathic V.D.: Idiopathic V.D. Minimum Data Base Physical Examination
Neurologic Examination
Only 8th nerve signs
Odoscopic Examination
Other tests as indicated
Heartworm Check
Fecal
Chest and Abdominal Radiographs
Idiopathic V.D.: Idiopathic V.D. Re-check in one week
Ought to be better
Re-check in one month
Should still be improving
Re-check again if any signs persist
Head tilt may be permanent Thought to be secondary to an immune act on the 8th nerve
Remember each cranial nerve is antigenically distinct
Can re-occur Summary of Case Management
Vestibular Diseases: Vestibular Diseases Vestibular Disease Idiopathic V.D. Inner Ear Disease Central V.D. 8th Nerve only 8th Nerve,
7th Nerve &
Horner’s Syndrome Anything Else
Inner Ear Disease: Inner Ear Disease 8th Nerve Signs
7th Nerve Signs
ear & lip droop
lack of palpebral reflex
nose turn
nostril flaring
Horner’s Syndrome
Inner Ear Disease: Inner Ear Disease Facial nerve dysfunction
diminished ear and lip reflexes
lack of palpebral reflex with inability to blink
diminished tear production
Horner’s Syndrome: Horner’s Syndrome Small Animals
Ptosis
Myosis
Enophthalmos
Large Animals
Facial sweating (horse)
Lack of muzzle sweating (cow)
Inner Ear Disease: Inner Ear Disease Most cases are secondary to bacterial infection (otitis media & interna)
extension from otitis externa
pharyngitis with extension up the eustachian tube
hematogenous spread
Inner Ear Disease: Inner Ear Disease Remainder are
fungal infections
ear polyps
neoplasia
Major rule:
“Treat for the Treatable”
Therefore, most need antibiotics!
Diagnosis of Inner Ear Disease: Diagnosis of Inner Ear Disease PE, NE, OE
Schirmer’s tear test
CBC
UA
Skull Radiographs
Other (if indicated)
Chest & Abdominal Radiographs
Ear Culture
Cardiac Exam Minimum Data Base Normal bulla radiograph
Note: sharp bone edges with symmetrical
appearance.
Inner Ear Infection: Inner Ear Infection Radiographic Findings Right-lateral and DV radiograph of dog with unilateral otitis interna showing
sclerosis of the tympanic bulla on the right side with loss of detail in the region
of the osseous petrous-temporal bone. R R L
Inner Ear Infection: Inner Ear Infection Treat with bacterio-cidal drugs which penetrate bone and blood-tissue barriers
Combination therapy
cephalosporins
sulfa drugs
Enrofloxacin
Must treat 6-8 weeks
Ear Polyps in Cats: Ear Polyps in Cats Benign growth in the external ear canal which causes signs by extension.
Can also be pharyngeal mass which grows into middle ear via the eusthasian tube.
Ear Polyps in Cats: Ear Polyps in Cats Treatment is surgical removal.
Damage can be permanent, if pressure necrosis has destroyed the inner ear structure.
Inner Ear Disease: Inner Ear Disease Other Neoplasia
neurofibromas
osteosarcomas
FeLV
Prognosis is Poor Other Infections
Fungal
Prognosis Guarded to Poor
Inner Ear Disease: Inner Ear Disease Consider Advanced Imaging Techniques
Bone Scan
MRI Scan
Consider Surgical Drainage of Bulla If owner can not afford additional tests or referral, may try changing antibiotics.
Main reason for failure is not treating long enough. What if Antibiotics Fail ?
I.E.D. (Special Dx- -Imaging): I.E.D. (Special Dx- -Imaging) Bone Scan
demonstrates enhanced uptake of radioisotope in region of infection.
MRI Scan
shows fluid levels or soft tissue proliferation.
I.E.D.- -MRI Scan: I.E.D.- -MRI Scan MRI Scan showing osseous proliferation and soft tissue density
in the osseous bulla.
B.A.E.R. test: B.A.E.R. test Provides indication of the ability of the auditory portion of the 8th nerve to function and relay that information through the brainstem toward the cerebral cortex.
Bilateral I.E. Disease: Bilateral I.E. Disease No Head Tilt
No Nystagmus
spontaneous or
physiologic
Wide head excursions due to inability to fix eyes on vertical with movement. Open mouth radiograph with
chronic changes in both bullas
Bilateral I.E. Disease: Bilateral I.E. Disease MRI image shows bilateral disease in middle and inner ear.
May respond to aggressive antibiotic therapy.
Some patients will also be deaf.
Inner Ear Disease: Inner Ear Disease Treat with antibiotics and recheck in 2 weeks
if better, continue
if worse, reassess
Recheck in 1 month
if normal, stop antibiotics
if still residual problems, continue 2 more weeks Recheck at 6 months
re-examine any abnormalities (such as abnormal bulla radio-graphs)
If problems worsens or persists without change for 4 weeks, consider referral. Summary of Case Management
Central Vestibular Disease: Central Vestibular Disease
Vestibular Diseases: Vestibular Diseases Vestibular Disease Idiopathic V.D. Inner Ear Disease Central V.D. 8th Nerve only 8th Nerve,
7th Nerve &
Horner’s Syndrome Anything Else The referral line
Nystagmus: Nystagmus Horizontal
Fast-Phase away from head tilt
Fast Phase toward head tilt
Rotatory
Vertical
Positional Peripheral V.D.
Central V.D.
Diagnosis of C.V.D.: Diagnosis of C.V.D. PE, NE, OE, FE
NE shows weakness, postural response changes, and/or reflex changes
CBC, Chemistry, UA
Skull Radiographs
CSF tap
CSF titers BAER test
Advanced Imaging
CT Scan
MRI Scan
Bone or Brain Scan
Surgical Biopsy Minimum Data Base The Referral Line
Central Vestibular Disease: Central Vestibular Disease Postural Changes
CP Deficit
Dysmetria
Reflex Changes
hyperactive reflexes
crossed-extensor reflexes
Babinski’s sign Conscious proprioceptive deficit
may be on the same or opposite side
of the lesion. Long Tract Signs
Central Vestibular Disease: Central Vestibular Disease CSF Analysis
may be normal or show increased pressure, protein and/or cells.
CSF Titers
species specific tests
many must be paired with serum titers. CSF Tap and Analysis CSF cytology form a dog exhibiting
a mixed reaction with neutrophils,
lymphocytes and macrophages.
Central Vestibular Disease: Central Vestibular Disease Inflammatory or Infectious Diseases
canine distemper
toxoplasmosis and neosporiosis
fungal
rickettsial
GME
SRME Common Causes of Diseases in Dogs
Central Vestibular Disease: Central Vestibular Disease Trauma or Vascular
remember dogs don’t get atherosclerosis !
Neoplasia
meningiomas
choroid plexus papillomas
oligodendrogliomas
astrocytomas
metastatic neoplasia Common Causes of Diseases in Dogs
Central Vestibular Disease: Central Vestibular Disease MRI of Brainstem Meningioma
Central Vestibular Disease: Central Vestibular Disease Primary Neoplasia Oligodendroglioma Choroid Plexus Papilloma
Central Vestibular Disease: Central Vestibular Disease Can be:
peracute
acute & progressive
chronic
In brainstem, tends to be a multifocal inflammatory disorder
Responds temporarily to steroids. Granulomatous Meningoencephalitis Patient with GME presenting with
vertical nystagmus, long tract signs,
and circling with incoordination.
Central Vestibular Disease: Central Vestibular Disease Granulomatous Meningoencephalitis GME histologically causes multifocal meningoencephalitis due to proliferation
of reticulohistiocytic cells. Lesions also show multinucleated giant cells.
Central Vestibular Disease: Neoplasia
meningiomas Central Vestibular Disease Infectious Diseases
FIP
FeLV
toxoplasmosis
cryptococcosis
Trauma
Metabolic
thiamine deficiency
Toxicity
organophosphates Common Causes of Diseases in Cats
Central Vestibular Disease: Central Vestibular Disease Common Causes of Diseases in Cats Don’t Forget Thiamine Deficiency !!! Brainstem hemorrhages secondary to thiamine deficiency.
Central Vestibular Disease: Central Vestibular Disease Most Common Cause is Infection of Brainstem by Listeria monocytogenes
50-75% respond to anti-biotic therapy
May result from invasion of infection into blood sinuses, resulting in Basillar Empyema
Common Causes of Diseases in Ruminants
Central Vestibular Disease: Central Vestibular Disease Listeriosis is common in adult cattle and goats.
Culture is difficult, requires cold-enhancement.
Treat with penicillins and sulfas for 2-4 weeks. Multifocal areas of hemorrhage due to
Listeriosis-induced meningoencephalitis. Common Causes of Diseases in Ruminants
Central Vestibular Disease: Central Vestibular Disease In Horses……
think
EPM!!!!!
(Equine Protozoal Myelitis) Common Causes of Diseases in Horses
Central Vestibular Disease: Central Vestibular Disease Signs include head tilt
paradoxical (head tilt is away from the lesion)
If horizontal nystagmus exists, the fast-phase is toward the head tilt
Also signs of dysmetria and whole body tremors (including head) Cerebellar Disorders
Central Vestibular Disease: Central Vestibular Disease The output of the cerebellum is through the activation of the Purkenjie cells. This output is inhibitory. When the cerebel-lum is damaged, the result is disinhibition of brainstem nuclei. Asymmetrical damage cause increased in motor tone on the side of the lesion, leading to the head tilting away from the damage.
Paradoxical Head Tilt in Cerebellar Disorders
Central Vestibular Disease: Central Vestibular Disease Chronic distemper in dogs
FIP in cats
Thiamine deficiency in cats, horses, and ruminants
OP intoxication in dogs and cats Lead poisoning in all animals
Meningiomas in dogs and cats Causes of Cerebellar Disorders
Central Vestibular Disease: Central Vestibular Disease MRI of Cerebellar Meningioma
Central Vestibular Disease: Central Vestibular Disease Corticosteroids
prednisolone @ 1 mg/kg/day in 3 divided doses for 3-7 days
reduce prednisolone dose to 1/3 mg/kg twice a day
find minimum daily dose and go to alternate-day therapy (over weeks) Misoprostol
3-4 µg/kg twice a day
may stop when at alternate-day steroids
Doxycycline
5-10 mg/kg once a day for 2 weeks
Sulfadimethoxine
15 mg/kg twice a day When Referral is Not an Option. TREAT FOR THE TREATABLE !!!