Spina Bifida P1

Question 1

general definition of spina bifida

Answer 1

aka spinal dyspharism and neural tube defect

congenital malformation and VC and SC

failure of neural tube to close in 3rd-4th wk

Question 2

epidemiology of spina bifida

Answer 2

whites

females

hispanic ethniity

Question 3

etiology of spina bifida

Answer 3

inc risk:

low folic acid intake

if may anak na may spina bifida = higher chance

pregestational diabetes and obesity

teratogenic drugs - valproate and carbamazepine

drugs used to induce ovulation

inc age

midspring conception

Question 4

recommended doses for folic acid

Answer 4

normal: 400 ug or 0.4 mg daily

previous NDT mother or high risk: 4000 ug or 4 mg daily (1-3 mo. prior to conception)

Question 5

week 2 of development

Answer 5

gastrulation = 3 germ layers

primitive streak in epiblast

Question 6

significance of ectoderm

Answer 6

outer most layer where nervous system is derived

Question 7

week 3 of development

Answer 7

neurulation = forming of neural tube
- primary and secondary phse

notochord secretes growth factor = ectoderm –> neuroectoderm –> neural endplate

Question 8

primary phase

Answer 8

week 3-4

neural plate thickens and bends –> folds to form hollow tube

cranial = brain
caudal = SC

Question 9

secondary phase

Answer 9

week 4-7

caudal part of neural tube becomes lumbar, sacral and coccyx segment

upper part does not close: anencephaly
lower part does not close: spino bifida

Question 10

discuss neural plate

Answer 10

forms by day 18 and becomes tube and crest

tube - CNS
crest - PNS

Question 11

closure of cranial end

Answer 11

24th day

Question 12

closure of caudal end

Answer 12

26th day

Question 13

discuss anencephaly

Answer 13

most severe NTD - dead na

neural tube does not close at base of skull

Question 14

discuss encephalocele

Answer 14

rare NDT - can be repaired surgically but c deficits

part of brain herniates through skull defect

Question 15

day 53 of development

Answer 15

caudal regression c rostral ext = SC

kaya lesions are before day 53 and usually sa lumbar and sacral

Question 16

2 major types of spina bifida

Answer 16

oculta

cystica:
- menigocele
- myelomenigocele
- myelocele

Question 17

discuss spina bifida oculta

Answer 17

mildest form - no herniation

lumbosacral segments

failure of one or more vertebral arches to fuse

(+) pigmented nevus, cafe au lait, hair on back, balat

(-) neuro and MSK deficits; arnold chiari and hydrocephalus

Question 18

possible complication of spina bifida oculta

Answer 18

bowel and bladder sx d/t tethered cored

Question 19

type of spina bifida that has neuro deficits

Answer 19

mga cystica

Question 20

discuss meningocele

Answer 20

herniation of meninges only - uncommon

lumbosacral

normal neuro exam and no chiari/hydrocephalus

at risk of tethered cord

Question 21

discuss myelomeningocele

Answer 21

herniation of meninges and neural tissue - most common and severe

lumboscaral

c chiari and hydrocephalus

abnormal motor and sensory below lesion

nuerogenic bowel and bladder

Question 22

discuss myelocele

Answer 22

cavity is ant to wall of SC - rare

lumbosacral

Question 23

discuss lipomeningocele

Answer 23

excess fat in VC and attached to SC

cyst has meninges and fat

Question 24

discuss rachischisis

Answer 24

most severe form - open sone

whole thoracic or cervical

assoc c anencephaly

deads

Question 25

discuss arnold chiari type 2

Answer 25

caudal herniation of medulla, lower pons, 4th ventricle, cerebellar vermis c hydrocephalus and common in myelomeningocele stridor apnea paralysis of vocal cords

Question 26

discuss tethered cord syndrome

Answer 26

causes arnold chiari 2nd most common cause of neuro decline hila pababa SX sudden spasticity/flaccid, weakness or worsening of LE and scolio

Question 26

common forebrain malformations

Answer 26

polymicrogyria heterotopia hyploplasia of thalamus agenesis of olfactory bulb and tracts agenesis of corpus callosum