neural tube defects

Question 1

where can neural tube defects occur

Answer 1

the brain and spinal cord

Question 2

what type of NTD is meningomyelocoele and where is the most common location

Answer 2

one that results from incomplete closure of the posterior spine during early development

the lumbar spine is the most common location

Question 3

what does the mass in meningomyelocoele contain

Answer 3

dysplastic: spinal cord, meninges, nerve root and CSF

Question 4

what associated abnormalities are found in meningomyelocoele

Answer 4

Arnold chiari malformation
dislocated hips
bladder dysfunction (catheterisatsation is the solution)
lower extremity weakness
somatosensory loss

Question 5

what are the two main types of NTD

Answer 5

Anencephaly
Spina bifida

Question 6

what is the phenomenon in which nerves becomes trapped in the mass of meningomyelocoele

Answer 6

Tethered spinal cord

Question 7

what happens in meningocele that does not happen in meningomyelocoele

Answer 7

the mass is covered by skin and you get minimal neurological deficits

• this is rare
  meningomyelocoele is the common condition

Question 8

what can you expect above the level of the meningomyelocoele lesion

Answer 8

nerve supply is usually normal unless there is a complication

Question 9

can you expect flaccid paralysis in meningomyelocoele

Answer 9

yes, due to lower motor neuron damage

Question 10

what happens when the lesion of meningomyelocoele is at L1

Answer 10

patients legs cannot be upright and they rely on wheelchairs to walk

Question 11

what happens when the lesion of meningomyelocoele is at L4

Answer 11

Patients cant walk without the use of walking aid, less severe than L1 lesion thus they can use walking stick

Question 12

what happens when the lesion of meningomyelocoele is at S2

Answer 12

patients have expanded leg curvature but can walk without the use of any aids

Question 13

what happens in spina bifida occulata

Answer 13

the lesion does not pierce through the vertebral bones and is covered by skin

Question 14

where is congenital dermal sinus usually found

Answer 14

between the nasal bridge and the sacrum

Question 15

what characterizes congenital dermal sinus in the sacral region

Answer 15

covered by skin (which can be normal, pigmented or distorted by overlying mass)
may appear as a dimple or sinus (sometimes covered by hair and sometimes it is not)

Question 16

what can congenital dermal sinus result to

Answer 16

may serve as tracts for infections within the dura mater and ultimately cause meningitis or abscess
the skin may be irritated

if the tracts expands into the thecal sac( the sac that contains the spinal cord) and form a mass cyst, the mass may appear as a tethered cord and in these circumstances cause bladder dysfunction.

Question 17

how is encephalocoele diagnosed

Answer 17

by ultrasound
infant after delivery

Question 18

what is encephalocoele

Answer 18

when there is extended brain tissue through the cranium
(could a result of cranial defect)

Question 19

what MRI scan is used in imaging for encephaloceole

Answer 19

T2

Question 20

What is Iniencephaly

Answer 20

it is a rare neural tube defect that involves the occiput and inion.
it is combined with rachischisis of the cervical and thoracic spine and also has retroflection of head

inion appears to have fused with the spine resulting in no discernible neck

Question 21

what are the two examples of anencephaly

Answer 21

myeloschisis (missing roof plate, vertebral arch and skin)
rachischisis (more extreme)

Question 22

what is exencephaly

Answer 22

disorder where the brain is located outside the skull

it is not a neural tube defect

Question 23

what is holoprosencephaly

Answer 23

sequence of events that caused by the failure proncephalon to suffiently divide into double lobes of the cerebral hemisphere causing a single lobed brainstructure and severe skull and facial defects

the malformations are severe to an extent of death

Question 24

what malformations are seen in the event of less severe holopronsencepaly

Answer 24

eye deformations
nose deformations
upper lip deformations

Question 25

what are the cause of less severe holopronsencepaly

Answer 25

genetics
drugs
alcohol
gestational diabetes