Sketchy Path: Neuro - "Neural Tube Defects, Holoprosencephaly, Chiari Malformation & Syringomyelia"

Question 1

The neural tube forms by the ___________ week of gestation.

Answer 1

4th (like the four calendar weeks on the wall)

Question 2

The most common cause of NTDs is ______________.

Answer 2

folate deficiency (like the bag of folate greens)

Question 3

Next to folate deficiencies, ______________ are the second most common cause of NTDs.

Answer 3

Drugs:

• Valproate
• Carbamazepine
• Bactrim
• Methotrexate

Question 4

Why is alpha-fetoprotein high in NTD?

Answer 4

It leaks through the pore and into the amniotic fluid (along with many other proteins). Because it can cross the BPB, it will be high in maternal blood.

(Think of Alf’s Fresh Produce behind the hamster tubes.)

Question 5

In addition to AFP, ____________ can be tested in the amniotic fluid to detect NTDs.

Answer 5

acetylcholinesterase (like the bottles of ACETYL cola WITHIN the tube city)

Question 6

Anencephaly results from _______________.

Answer 6

failure of the anterior neuropore to close (like the skull on the one tube with the top of its cranium popped open)

Question 7

Anencephaly causes what in pregnancy?

Answer 7

Polyhydramnios due to failure of the fetus to swallow amniotic fluid (like the baby hamster swimming in spilled water)

Question 8

What other disorder results from failure of the anterior neuropore to close?

Answer 8

Encephalocele (like the skull with a bleb on it next to the anencephaly skull)

Question 9

Spina bifida is when _____________.

Answer 9

the posterior vertebral arch fails to close (like the hamster hopping over the gap between ramps that resembles vertebral arches)

Question 10

Meningocele is also known as _____________.

Answer 10

spina bifida cystica, because of the cyst-like protrusion of dura through the skin (like the hamster in the dome)

Question 11

Babies with myelomeningocele often present with _____________ at birth.

Answer 11

bowel/bladder incontinence (like the hamster peeing)

What baby doesn’t have incontinence, though?

Question 12

Holoprosencephaly results from ________________.

Answer 12

failure of the right and left hemispheres to divide (like the two mice entwined in the ball)

Question 13

Mutations in _______________ can cause holoprosencephaly.

Answer 13

sonic hedgehog (like the sonic ball that the holoprosencephaly mice are in) and trisomy 13 (like the 13 brand ball)

Question 14

Which type of Chiari malformation presents with NTD?

Answer 14

II (like the two cherries in the NTD tube city)

Question 15

Chiari I has what malformation?

Answer 15

Cerebellar tonsils protruding more than 5 mm past the foramen magnum (like the ONE cherry getting sucked out of the bottom of the posterior fossa bowl by the hamster)

Question 16

Although Chiari I is most often asymptomatic, it can cause ___________________.

Answer 16

syringomyelia (string bean in hamster tube), ataxia (woman shaking), UMN symptoms (reflex hammer and clasp knife) and headache from meningeal irritation (woman clutching her head)

Question 17

Arnold-Chiari is type ______.

Answer 17

II (like the two cherries getting sucked down the tube with the other fruit –representing the vermis)

Question 18

Which type of Chiari can cause hydrocephalus?

Answer 18

Type II (like the overflowing sink behind the type II bowl)

Question 19

What is Dandy-Walker syndrome?

Answer 19

A cystic dilation of the fourth ventricle that results in a large posterior fossa and hydrocephalus (like the tight-rope WALKER going toward the bowl with the massive fruit in the posterior fossa)

Question 20

Syringomyelia compresses which part of the spinal cord?

Answer 20

Anterior white commissure (like the cape connected in the anterior part by white rings)