lecture notes on fetal alcohol syndrome and Spina bifida

1. Lecture notes 7: FAS
Definition:Fetal alcohol syndrome referstothe growth,mental,andphysical problemsthatmay
occur in a babywhena motherdrinksalcohol duringpregnancy.
Types inthe Spectrum
 Fetal Alcohol Syndrome (FAS),
 partial Fetal Alcohol Syndrome (pFAS),
 Alcohol-RelatedBirthDefects(ARBD)
 Alcohol-RelatedNeurodevelopmental Disorder(ARND)
Clinical Features
• Failure to thrive due to being premature
• Developmental delays
• Organ dysfunction
• Epilepsy
• Poor growth while the baby is in the womb and after
birth
• Decreasedmuscle tone and poor coordination
• Heart defects
• Structural problemswiththe face
• Difficultieswiththeirrespiratory system
• low birth weight
• small headcircumference
• poor coordination/fine motor skills
• poor socializationskills
• Learning difficulties
• Behavioural problems

2. 7 Domains
• Cognition
• Adaptation
• Executive function
• Memory
• Communication
• Attention
• Achievement
Criteriafor Diagnosis
a) growth deficiency:lowbirthweightand/ordeceleratingweightovertime notdue to
nutrition
b) characteristic pattern of facial anomalies: shortpalpebral fissures,flattenedphiltrum, thin
upperlip,flatmidface
c) central nervoussystem dysfunction:microcephalyand/orneurobehavioural dysfunction
(hyperactivity,finemotorproblems,attentiondeficits,learningdisabilities,cognitive
disabilities,difficultiesinadaptive functioning,etc.

3. Spina Bifida
Definition:Disordercausedbythe incompleteclosingof the embryonicneural tube. Some
vertebrae overlyingthe spinalcord are not fullyformedandremainunfusedandopen. If the
openingislarge enough,thisallowsaportionof the spinal cordto protrude throughthe opening
inthe bones.
Other definitions:
Meningo- Meninges
Myelo- Nerve Sheaths
Cele- Tumor/Cyst/Sac
Embryology
• Spinabifidaiscausedbythe failure of the neural tube toclose duringthe firstmonth
of embryonicdevelopment(oftenbefore the motherknows she ispregnant).
• Under normal circumstances,the closure of the neural tube occursaroundthe 23rd (rostral
closure) and27th (caudal closure) dayafter fertilization.
Etiology:
• Maternal diabetes
• Familyhistory
• Obesity
• Increasedbodytemperature
fromfeveror external sourcessuchas
hot tubsand electricblanketsmay
increase the chancesof deliveryof a
babywitha spinabifida.
• Medicationssuchas
some anticonvulsants.
• PregnantwomentakingValproicacid
have an increasedriskof having
childrenwithspinabifida
• Geneticbasis.
• Folicaciddeficiency
Types
 SpinaBifidaOcculta
 SpinaBifidaCysticaWithMeningocele(Aperta)
 SpinaBifidaCysticaWithMyelomeningocele. (Aperta)

4. Spina BifidaOcculta
• congenital absence of aspinousprocessandavariable amountof lamina
• novisible exposureof meningesorneural tissue
Clinical Features
• noobviousclinical signs
• presence of lumbosacral cutaneousabnormalities(dimple,sinus,port-wine
stain,or hair tuft)
Investigations
• plainfilm:absence of the spinousprocessalongwithminoramountsof the neural arch
• U/S,MRI to exclude spinalanomalies
Treatment
• requiresno treatment
MENINGOCELE(SPINABIFIDA APERTA)
Definition
• herniationof meningeal tissue andCSFthrougha defectinthe spine,without
associatedherniationof neural tissue
Clinical Features
• mostcommonin lumbosacral area
• usuallynodisability, lowincidence of associatedanomaliesandhydrocephalus
Investigations
• plainfilms,CT,MRI,U/S, echo,genitourinary(GU) investigations
Treatment
• surgical excisionandtissue repair(excellentresults)

5. MYELOMENINGOCELE(SPINABIFIDA APERTA)
Definition
• herniationof meningeal andNerve sheath througha defectinthe spine
Clinical Features
• sensoryandmotorchangesdistal to anatomiclevel producingvaryingdegrees
of weakness
• urinaryandfecal incontinence
• 65-85% of patientswithmyelomeningocele have hydrocephalus
• mosthave Type II Chiari malformation
Investigations
• plainfilms,CT,MRI,U/S, echo,GU investigations
Treatment
• surgical closure topreserve neurologicstatusandpreventCNSinfections
• closure in-uteroshowntodecrease hydrocephalusandimprove postnatal motorscores
Diagnosis:
 alpha-fetoprotein(AFP)
 Maternal Serumalpha-fetoprotein(MSAFP
 Ultrasound
 Amniocentresis
Complications
• Difficultdeliverywithproblemsresultingfromatraumatic birth,includingcerebral palsyand
decreasedoxygentothe brain
• Frequenturinarytractinfections
• Hydrocephalus
• Loss of bowel orbladdercontrol
• Meningitis
• Permanentweaknessorparalysisof legs