40.CONGENITAL AND NEOPLASTIC DISEASES OF THE NERVOUS SYSTEM IN DOGS AND CATS

Question 1

what are he congenital diseases of the nervous system?

Answer 1

1. Hydrocephalus
2. Lyssencephalon
3. Cerebellar hypoplasia
4. Chiari malformation
5. Syringomyelia

Question 2

Define hydrocephalus

Answer 2

Hydrocephalus (hc): abnormal dilation of the ventricular system within the cranium.

Question 3

What types of hydrocephalus do we have?

Answer 3

• Compensatory hc: CSF takes over the place of the lost parenchyma.
• Ostructive hc: flow or absorption of the CSF is obstructed (intra- or extraventricular obstruction).
• Congenital hc: malformation that interfere with the flow or absorption of CSF.
• Acquired hc: neoplasia, inflammation, trauma → interfere with the flow or absorption of CSF.

Question 4

what happens when we have CSF accumulation?

Answer 4

• CSF accumulation → elevated CSF pressure, loss of neurons

Question 5

Therapy of hydrocephalus?

Answer 5

• anti seizure drugs, carbonic anhydrase-inhibitors, protonpump inhibitors, corticosteroids, mannizol inf. in case of symptoms

Question 6

What is lyssencephalon?

Answer 6

• Smooth brain appearance with no or minimal gyri and sulci.

Question 7

What is cerebellar hypoplasia?

Answer 7

• In cats after in utero-perinatal infection with feline panleucopenia virus
• In dogs after in utero-perinatal parvoviral infection
• Cerebellar malformation (vermis hypoplasia) alone or in association with ventricular dilatation, or with lissencephalon. (rare)

Question 8

What is chiari malformation?

Answer 8

• Chiari malformation is a human disorder, animals have similar phenomenon (Chiari-like malformation)
• Short cranium and occipital malformation→ herniation of the cerebellum through the foramen magnum
• Breed predispostion: Cavalier King Charles spaniel

Question 9

Clinical signs of chirai-like malformation: (common)

Answer 9

Common

• Spontaneous yelping
• Phantom scratching – most common
• Pain upon palpation of neck
• Facial pruritus/rubbing
• Pain when picked up
• Irritation with collar/harness
• unprovoked vocalizations seemingly resulting from poorly localizing pain.

Question 10

Clinical signs of chirai-like malformation: (less common)

Answer 10

• Seizures
• Tail chasing
• Air licking
• Paw licking
• Proprioceptive deficit
• Lethargy
• Reluctance to jump
• Vestibular dysfunction
• Other cranial nerve deficit
• Scoliosis
• Pain while defecating

Question 11

What is syringomyelia?

Answer 11

Syringomyelia: cavitation in the spinal cord parenchyma
Hydromyelia: dilation of the central canal of the spinal cord

• Differentiation is difficult → syringo hydromyeliais used
• They occur secondary to a herniation of the cerebellum through the foramen magnum
• Most commonly occurs in the cervical spinal cordas multifocal or continuous lesion

Question 12

Symptoms of syringomyelia?

Answer 12

Symptoms: excessive scratching of the ears, neck shoulder, proprioceptive ataxia, postural reaction deficits, neuropathic pain

Question 13

Primary vertebral tumors:

Answer 13

• fibrosarcoma, osteosarcoma, chondrosarcoma, hemangiosarcoma, myeloma, hemangioendothelioma

Question 14

secondary vertebral tumors:

Answer 14

• mammary, prostatic, thyroid carcinomas, malignant melanoma, metastatic osteosarcoma

Question 15

Epidural tumors:

Answer 15

lymphoma, metastatic tumors

Question 16

Indradural-extramedullary tumors (primary and secondary)

Answer 16

meningioma, peripheral nerve sheat tumor, lymphoma, nephroblastoma

Question 17

Intramedullary tumors:

Answer 17

astrocytoma, oligodendroglioma, ependymoma, metastatic

Question 18

Clinical signs of tumors:

Answer 18

• Symptoms depend on the location of the lesion.
• Pain!
• Transversal myelopathy
• Any breed, most common in older large breed dogs
• Cats: lymphoma, meningioma, osteosarcoma!