PEOPLE

1. PEOPLE “The man who smiles in the face of trouble… Has found someone to blame it on.”

2. Anatomy Supratentorial: better prognosis Infratentorial forebrain is responsible for "thinking," behavior, and final integration of sensory information

3. Brain: Neoplasia Enlarging mass in brain; causes compression of healthy tissue or replacement with cancerous tissue • Primary: meningioma, glioma, choroid plexus papilloma, pituitary adenoma or adenocarcinoma (cushing’s), and others. • Secondary (metastasis): hemangiosarcoma, mammary carcinoma and melanoma • Dogs most common meningiomas and gliomas • Sagittal MRI of the brain of an 8 year old female German Shepherd dog. • Seizure • Well encapsulated mass in the olfactory bulb and frontal cortex of the brain • Meningioma (histopathology) • TX: surgical removal of the tumor followed by radiation • PX: Good not touching brain (unlike gliomas: radiation therapy)

4. Hemangiosarcoma

5. Brain: Neoplasia • Forebrain • Behavior • Depression, loss of learned behavior • Seizures: acute onset, 5-6 yrs old • Pacing and circling (Vestibular signs) • Ipsilateral vision: bump • E.g. Glioma’s and new treatments • Brachycephalic breeds: such as the Boxer, the Boston terrier, and the French and English bulldog

6. Brain - Neoplasia • The Brainstem • motor function (the ability to walk, CV and resp function), consciousness and balance • 1st signs: loss of balance (vestibular signs) and paresis of one side of the body • Dysphagia, change in voice and inability to move the eyes • Progresses into paralysis, coma and death. • Vestibular signs: • Head tilt • Leaning and falling to the side of the head tilt • Drunken gait with loss of balance (ataxia) • Circling to the side of the head tilt • nystagmus • Anorexia and vomiting • Strabismus

7. Kasey, a 10-year-old female Golden retriever • trigeminal nerve root tumor • sensation to the face and motor function to the muscles of mastication • 15 months

8. Brain - Neoplasia • The Cerebellum - coordination of movements and interacts closely with the vestibular system to control balance and posture. • Uncoordinated gait characterized by dramatic goosestepping (hypermetria) • Intention tremors: Head tremors that are worst when the animal is intent on something (i.e., food) but disappear when the animal is relaxed Swaying of the trunk • Wide based stance • Sometimes there can be vestibular signs such as a head tilt • The animal's strength remains normal

9. Brain: Neoplasia • Dx • Systematic screening for tumors in other organs • CBC, chem panel • Radiographs: metastasis • CSF tap to assess increased cerebral spinal pressure • Ophthalmic exam may indicate optic nerve edema • Computed tomography (CT) scanning or magnetic resonance imaging (MRI) to locate tumor

10. CT or MRI • MRI • shows the brain in more detail than CT • the test of choice when assessing for brain tumors • more expensive test and less widely available • CT images (more artifacts for brainstem/ cerebellum): meningiomas, choroid plexus papillomas • MRI: gliomas, brainstem or cerebellar disease or Boston Terrier.

11. Brain: Neoplasia • Rx— surgical removal, radiation therapy, chemotherapy, and palliative treatment of the symptoms • Surgical removal of superficial single lesions • Tumors of the brainstem pose problems • Forebrain: you can resect certain parts of the forebrain without long-term effects. • Meningiomas tend to be located on the surface of the brain and are therefore the best candidates for surgical removal. • Gliomas are more difficult to remove because they lie deep within the substance of the brain.

12. MRI of a 6 year female old Boxer oligodendroglioma

13. Brain: Neoplasia • Radiation therapy • Chemotherapy; efficacy varies with tumor type (lymphomas respond well; other less so) • Palliative: Anti-seizure medication (Phenobarbital PO 2-3 times/day), Corticosteroids—prednisone • Client info • The more severe the signs, the worse the outcome • The larger the tumor, the worse the outcome • Supratentorial tumors (tumors of the forebrain) have a better prognosis than infratentorial tumors (tumors of the brainstem and cerebellum) • Radiation therapy does prolong lifespan in most cases • Meningiomas have a better outcome than tumors that lie within the brain (e.g. gliomas)

14. Epilepsy • MOA: balance within the brain shifts too far toward excitation, too many cells may become too excited and a seizure can result

15. Epilepsy • Generalized/ tonic (stiff muscle) - clonic (rhythmic movements: grand mal) • Grand mal (motor) • Prodrome • Ictus: the seizure itself • post-ictal(post-seizure) • Petit mal (absence seizure): little movement, animals? • Focal/ Partial • focal seizure may stay localized • may spread and affect the whole brain causing a classic, generalized, tonic-clonic seizure • brain tumor or infection • Simple: motor, twitching or blinking to one side of the face • Complex: sensory. Senseless repetitive behavior: imaginary fly biting,

17. Seizures When the seizure begins, the dog stiffensand falls; They then begin jerking movementsThey are not in pain during the seizureand cannot control their bladder or bowels.

18. Epilepsy • Signs of seizure • short aura (stare into distance, seek comfort/protection from someone, vocalize) • seizure lasts 1-2 min; may consist of total body muscle twitching with extended arms and legs and arching of neck dorsally (opisthotonus) • dog will be disoriented/blind for a few minutes Click for video

19. http://www.thepetcenter.com/gen/epilepsy.html • may be incited by certain events • normal at other times

20. Epilepsy • Dx • CBC, chem panel—r/o metabolic diseases causing seizures • hypoglycemia • hypocalcemia • hepatic encephalopathy (failure to detox blood) • Shunt • Cirrhosis • Pb poisoning • Radiographs—r/o head trauma or hydrocephalus • CT scan or MRI—r/o space-occupying lesion in brain • Rx—directed at cause if one can be found • treat if >1 every mo or two (Rx will not completely stop seizures) • Phenobarbital is TOC

22. Status Epilepticus • Signs—prolonged, uninterrupted seizures (>5-10 minutes) or cluster of seizures • Rx • Diazepam (2-10 mg to effect); can be repeated over several minutes • Phenobarbital - • Time to steady state blood levels: 10-14 days • Side effects: sedation, ataxia, PU/PD/PP, hepatotoxicity, blood dyscrasias (Rare) • Establish an open airway • IV cath with IV fluids to keep an open vein • Monitor blood Ca and glucose; treat is needed • Monitor body temp; if elevated, treat appropriately • If cerebral edema is suspected, treat with mannitol (IV) • Phenobarbital—IV or IM

23. Status Epilepticus • Client info— • Epilepsy is an incurable disease • Even with treatment, animal may still seize; • goal is to reduce frequency and intensity of seizures • Spaying/neutering will remove any hormonal influence on seizures • Medications will probably be required for life • Most animals that seize can live a normal life • If seizure free for 6-9 mo, may reduced or discontinued Rx

24. LIFE “Life is the art of drawing without an eraser.” -John w. Gardner

25. Spinal Cord • Function • Nerve fibers carry signals between brain - rest of body • Anatomy • Like brain, protected by hard covering – dura • Intervertebral disk (cushion): • between vertebral body • increases range of motion • prevents vertebrae rubbing

26. Spinal Cord: Anatomy Like brain, spinal cord enclosed in hard covering IVDD problem in both humans and canine Anatomical differences—cervical same; lumbar—human bears weight, canine doesn’t Attached rib (thorax) helps stabilize the IV joint; worse at T-L junction (dogs)

27. Degenerative Disc Disease: Humans Degeneration of disk occurs with age Dries out, shrinks (we get shorter as we age)

28. IV Disk Disease: Anatomy Normal spinal column and disk Prolapsed disk 1/3 thickness nucleus fibrosus

29. Intervertebral Disk Disease • Etiology • IVD dries out with age → hardened, less compliant • ↑Pressure from jumping • Occurs most commonly in cervical, caudal thoracic, and lumbar vertebrae • Most common spinal cord disorder in companion animals

30. Intervertebral Disk Disease • Hansen TYPE I: Nucleus pulposus herniates upward; narrowest part of annulus fibrosus • TYPE I: Most common in chondrodystrophic (“faulty development of cartilage”) breeds • Dachshunds, shih tzus, Lhasa apsos, beagles, basset hounds (poodles also affected) • Acute onset • Can occur at any age, but generally younger dogs

31. Intervertebral Disk disease • Hansen TYPE 2: dorsal protrusion of the annulus into the spinal canal • Common in older dogs and nonchondrodystrophic breeds • Occurs over a longer period of time • Clinical signs may be less severe • Generally older dogs

32. Intervertebral Disk Disease • Signs: • Pain • Paresis/paralysis; nerve function is lost in this order: • Proprioception—largest fibers; most susceptible to pressure; signs are ataxia • Motor fibers—next smallest fibers; signs are weakness/paresis • Cutaneous sensory fibers—small; require a lot of pressure to disrupt function; decreased panniculus reflex • Deep pain fibers—smallest fibers; require the most pressure to disrupt; loss is associated with poor prognosis • Severity of clinical signs depends on: • Speed at which disk material is deposited • Degree of compression • Duration of compression

33. IVDD – Paralysis of rear legs

34. Cervical IVDD

35. Loss of Deep Pain

36. IVDD Dx: Spine X-Rays Normal horse’s head consistent IV space Subluxation L2-3 (old lesion)

37. IV Disk Disease: Myelogram: Definitive diagnosis Which disk space?

38. IV Disk Disease: Myelogram Which disk space?

39. Cervical IVDD Myelogram: Disk herniation at C2-3 (narrowed IV space, narrowed spinal canal)

40. IVDD • Rx TYPE I, acute onset • Medical Rx is recommended for animals, with deep pain intact, with or w/o neuro deficit • High levels of corticosteroids is CONTROVERSIAL • Strict confinement—2 wk minimum (easy when dog hurts; not so easy after steroids/other pain medications take effect) • Nursing care • Soft padded cage • Urinary cath or express bladder several times/day • Surgery is recommended for • repeat offenders • No voluntary motor function • loss of deep pain (needs to be done QUICKLY!) • worsening neuro signs (poor Prognosis)

41. Laminectomy

42. IVDD: Possible sequela

43. IVDD

44. IVDD - rehabilitation http://www.youtube.com/watch?v=7AkNVDc4lig&feature=related

45. IVDD – Alternative/Optional Treatment • Methocarbamol (muscle relaxant)15-20 mg/kg q 8hr • High-dose Methylprednisolone sodium succinate (CONTROVERSIAL!) and should be given within 8 hours • Although there is proven benefit in humans, results have not been proven in dogs • Low dose prednisone – various regimens • NSAIDS • Carprofen, deracoxib, etodolac • Gastroprotectants • Acupuncture

46. Veterinary Acupuncture • http://www.youtube.com/watch?v=Z-JjZPnk_Mw&feature=related • http://www.youtube.com/watch?v=vJIJDUQyOmw&feature=fvw

47. IVDD • Client info • Do not let susceptible breeds get overweight • Encourage animals to keep spine parallel to ground • No jumping on/off couch • No begging on hind legs • No stair climbing • Loss of deep pain >24 h has poor prognosis • If surgery is done soon enough, there is a good Px of recovery • Almost half of animals treated medically will have recurrence • Extensive home care is required for medical and surgical patients • Severe damage to spinal cord is not reparable

48. Atlantoaxial Joint Atlanto-Axial Joint

49. Atlantoaxial Instability (Subluxation) • Signs • Toy and miniature breeds (<1 yr) • Reluctance to be patted on head • Neck pain • May have tetraparesis (weakness in all 4 limbs) or tetraplegia (paralysis in all 4 legs) • Sudden death due to respiratory paralysis • Diagnosis— • Radiographs: lateral x-ray of neck in slight ventroflexion • avoid further spinal cord damage with positioning