Developmental defects and neoplasia

List the parts of the brain in the order in which they develop?

1. brainstem

2. cerebrum

3. cerebellum

Injuries that happen to the brain early and that are quite severe cause what?

aplasia

Injuries that happen to the brain early but are only moderate may cause what?

segmental aplasia

Injuries that happen later in the development in the brain would cause what?

hypoplasia

Tissue that fails to from has undergone what?

aplasia

Tissue that is smaller than expected is called what?

hypoplasia

Tissue disorganization and other changes at a microscopic level is known as what?

dysplasia

aplasia, segmental aplasia, hypoplasia, are all accompanied by some degree of __________

dysplasia

a defect in the neural tube closure is clalled what?

Dysraphism

Proper formation of the spinal cord has an impact on what structures that surround it?

• vertebral bodies

• mesoderm

Spinal cord tissue that has open access to overlying integument is called what?

meningomyelocoele

A defect in the overlying skull bones due to improper brain development is called what?

cranioschisis

any agent that causes rapid death of rapidly dividing cells is called what?

radiomimetic

missing a major potion of the brain is known as ___________ and can occur due to ________ in cattle

• anencephaly

• BVDV

What would infection at these BVDV time points between 100-170 days cause in terms of brain development:

• early

• middle

• up to 170

• cerebral aplasia/hypoplasia

• porencephaly

• cerebellar aplasia/hypoplasia

The difference between cerebellar hypoplasia and cerebellar abiotrophy is that hypoplasia is ____________

static

On histology a way to tell the difference between hypoplasia and abiotrophy is the presence of ________ in the tissue

necrosis

In hypomyelinosis oligodendrocytes are _______ but they cant make _________

• normal

• myelin

In sheep what can cause hypomyelinosis

Border disease virus

Border diseae virus infection causes infection of _________ in sheep

fetal thyroid follicular cells

thyroid hormone is required for ________ to form myelin

oligodendrocytes

_________ is an important cofactor in myelin and deficiency in utero can cause _____________ while deficiency postnatally can cause __________

• copper

• swayback

• enzootic ataxia

Between swayback and enzootic ataxia which one causes hypomyelination and which causes demyelination

• swayback is hypomyelination

• enzootic ataxia is demyelination

Hydrocephalus has what 3 criteria?

• impeded CSF flow

• increased intracranial pressure

• atrophy of periventricular tissue

What are the 2 bottle necks in CSF flow

• mesencephalic aqueduct

• lateral aperture

hydrocephalus caused by an _________ increase in pressure is life threatening

acute

What are the most common tumors in the CNS

• glia

• mesenchymal

What tumors predominantly arise in young animals

primitive neuroectodermal tumors

are secondary tumors common in the CNS

yes

is it possible for lymphoma to be a primary tumor in the CNS

yes

A non attached yet compressive mass is found on gross histology you would assume this was a what?

meningioma

On gross histology a internal yet compressive tumor has arised and appears to be highly vascular you would assume this was a what?

oligodendroglioma

A neoplasm found in the ventricle could be what things?

• choroid plexus tumor

• ependymoma

When suspecting or finding tumors in the CNS you should do what?

check elsewhere in case of metastasis

when you see mass effect on imaging and gross examination a lot of it is due to __________

edema