Neuro Flashcards
What decreases CBF (cerebral blood flow)?
Decreased PCO2
Increase paO2
Increase Hb [ ]
Decreased fetal Hb
Muscle biopsy findings with
1. Myotubular myopathy
2. Myotonic dystrophy
3. SMA
4. Muscular dystrophy
- Large fibrils, centrally placed nuclei
- Small fibers, centrally placed nuclei
- Hypotrophy fascicles with hypertrophic fascicles
- Replaced by fat, connective tissue and peri placed nuclei
What are U/S findings with Meningomyelocele?
Lemon 🍋 sign - compression due to CSF leak
Banana 🍌 sign - compressed cerebellum
Mother with difficult labor
Polyhydramnios
Baby with respiratory failure and tent shaped mouth, and hypotonia
Myotonic Dystrophy
Polyhydramnios; difficulties swallowing
Dysfunctional Na /K channel
AD; chromosome 19 (DMPK gene)
CTG repeats
Baby with decreased fetal movements, hypotonia, bell shaped chest on CXR, frog leg position
Dx?
Test?
SMA
EMG - Abnormal activity with fibrillation and fasiculations
Bulbar weakness (poor suck/swallow, weak cry, tongue fasiculations)
Marked head lag
Facial sparing
Absent deep tendon réflexes (aréflexia)
Normal diaphragmatic function
AR, chromosome 5
Degeneration of anterior horn cell
Earliest imaging modality to detect HIE
MR spectroscopy
Can detect inc in brain lactate concentrations as soon as 2-8 hrs after injury
Neural tube defects have highest rate among which population?
Hispanic patients
Teenage
Which is most effective intervention to decrease risk of IVH?
Prenatal steroids
Neonates with transient neonatal myesthenia gravis present most commonly with?
3hrs-24hrs: Poor suck and swallow, weak cry, resp distress and ptosis/ophthalmoparesis
Abs against the Nicotinic Acetalcholine receptor 80% or muscle specific receptor tyrosine kinase 20%
Atypical presentation can be arthogryposis multiplex congenita
Majority need neostigmine
Duration of illness ~18 days
Hyperthermia following HIE leads to neuronal cell death in which region?
Hippocampus
Which type of CP do you expect in severe HIE?
Pyramidal CP
Cerebral tissue hypoxia results in reduction of?
ATP and Phosphocreatinine->influx of intracellular calcium
Protease activation leads to cytoskeletal disruption
Protease and phospholipase activation leads to apoptotic Pathways
Cellular mechanism of HIE
Cerebral tissue hypoxia results in decreased production of ATP and phosphocreatine
which leads to cell membrane depolarization and influx of intracellular calcium.
This influx in intercellular
Ca+ results in the activation of multiple downstream pathways including~
Endonuclease activation that results in nuclear injury
Protease activation leading to cytoskeleton disruption
Protease and phospholipase activation that results in free radical production and activation of the
apoptotic pathways
Nitric oxide synthase activation
An increase in excitatory neurotransmitter (glutamate) release
Most common risk factors for perinatal brachial plexus palsy?
Shoulder dystocia (45%)
Newborn with dolichostenomelia, High arched palate, mitral valve prolapse and joint contractures (fingers, Elbows and knees). Dx?
Congenital contractural arachnodactyly AKA Beals syndrome
Mutation in fibrillin gene-2 on chromosome 5
Think marfans with contractures
Marfans syndrome, dolichostenomelia (long extremities), aranchmodactyly, joint contractures fingers elbows knees, MVP
Describe DANDY walker malformation
Agenesis of cerebellar vermis, cystic dilation of 4th ventricle and enlargement of posterior fossa
Describe Arnold chiari malformation II
Present in childhood/adulthood
Displacement of cerebellar tonsils below foramen magna
4th ventricle and brainstem normal
Syringo or hydromelia
Ass w scoliosis
Type 2 p/w infants
Elongation and caudal displacement of cerebellar tonsils, 4th ventricle choroid plexus
Ass w/Hydrocephalus
What syndromes present w agenesis of corpus callosum?
Neuro-dandy walker, holoprosencephaly
Metabolite non ketotic hyperglycinemia, pyruvate dehydrogenase deficiency
T8, 13,18
Aicardi syndrome-infantile spasm, Coloboma hypotonia
Zellweger-peroxisomal disorder
A GMFCS of 5 indicates a higher or lower likelihood of severe limitations in CP?
Higher (5)
lower (1)
MC Type of CP in bilirubin encephalopathy
Athetoid (increased activity with reduced tone)
Most common CP in preterm neonates is ….
Spastic diplegia
Cognitive function is not usually affected (unless quadriplegia)
Fine motor usually not affected
(Is affected in dyskinetic - AKA extrapyramidal -
- dystonic: reduced activity with increased tone or -choreoathetotic : increased activity with decreased tone)
Prenatal repair of myelomeningocele is associated with
Risk of sx: maternal morbidity, preterm birth, increased Uro complications
Stopped early because of a reduced need for CSF shunt in prenatal intervention group by 12 months
Decrease in fetal/neonatal death
Improved mental/motor function at 30 months
Sx recommended in: Singleton pregnancy, Lesion at spinal level T1-S1, normal karyotype and Arnold Chiari type 2
Describe aEEG findings in normal vs burst suppression vS seizures.
Continuous amplitude 10-25mcV (appears like a fuzzy caterpillar)
Discontinuous-wide band w min amplitude below 5 and max>10
Burst suppression-discontinuous w min amplitude 0-1mcV with burst>25 (<100 bursts/hr negative burst suppression, >100 bursts/hr positive burst suppression)
Low voltage- continuous pattern around/below 5
Inactive iso electric, low background amplitude<5
Seizures- saw tooth pattern, inc min and max amplitudes
Abnormal aEEG at 48 hrs predictive of NDI and neg aEEG at 6hrs predictive of No NDI
What is the mechanism of action of hypothermia In decreasing hypoxic injury?
Decrease intracellular Ca influx and mitochondrial dysfunction
Decrease free radical production
Reduced STAT 3 expression
Enhance RBM3 protein expression
Decrease in metabolic demands
What are some short term Neuro outcomes from morphine use in the NICU?
Longer time to achieve full volume feeds
Longer # of days on ventilator
Strong predictor of severe NEC
Name biomarkers to predict HIE injury in MRI
Elevated IL 6 in neonate but not mother correlates w NDO at 2 years
Glial fibrillation acidic protein (GFAP) elevated after HIE
Brain derived neurotrophic factor (BDNF) high in cord plasma
Protein S100beta elevated in cord blood
What are long term outcomes for SSRI- exposed children ?
ADHD
Term infant
Ashkenazi Jewish family Hypotonia
Autonomomic issues (loose, irritability, Pale blotchy skin)
(think NAS with hypotonia)
Riley - Day syndrome (Familial dysautonomia)
AR
Chromosome 9
Dx- pupil construction in response to metacholine eye drops
Describe CN and function
I- Olfaction
II- Vision, optic fundi
III- Pupils
III, IV, VI-Extraocular movements
V-Facial sensation, masticatory power
V1: ophthalmic
V2:maxillary
V3: mandibular
VII- Facial movements
VIII-Auditory
V, VI, IX, X, XII-Sucking and swallowing
XI-Sternocleidomastoid function
XII-Tongue
VIII, IX- Taste
Pt with expressionless face. What’s the syndrome?
Mobeus syndrome
Secondary to hypoplasia or absence of CN nuclei
No treatment or recovery
Which EEG pattern is seen in PVL?
Central positive sharp waves
What is the diagnostic test for neonatal myesthenia gravis?
Anti-acetylcholine receptor antibody assay
Anti-AChr 85% (nicotinic receptor)
Anti-Muskr 15% (muscle specific receptor tyrosine kinase)
Which is the primary cellular target in PVL?
Oligodendrocyte progenitor cell
Brachial plexus injury associated with Horners
Klumpke (T1)
When do u expect full recovery of brachial plexus injuries?
6 months
@2 mo you see improvement
If residual impairment at 15 months, usually persists
Brachial plexus injury with Phrenic nerve paralysis
Erb (C4-C5)
Describe the presentation triad of Aicardi syndrome
Agenesis of corpus callosum
Infantile spasms
Chorio retinal lacunae
Autosomal dominant 46XXY
Term female with focal clonic seizure at 5 days of life confirmed on EEG. No fhx of seizure. What type of seizure is she exhibiting?
Benign neonatal seizure aka “fifth day fits”
Term newborn with hypotonia, arthrogryposis multiplex congenita, and dilated cardiomyopathy. Muscle biopsy with gomori trichrome staining with rodlike bodies. Dx?
Nemaline myopathy (remember Nemaline bodies)
Absent DTR and severe muscle weakness affecting face/proximal limbs
The location of white matter injury in preterm neonates is specific to which area? And why?
Periventricular area
Distribution of oligodendrocyte progenitors
Which of the following interventions is most likely to prevent IVH?
- Antenatal magnesium
- Antenatal Vit K
- Delayed cord clamping 60 sec
- Indomethacin treatment within 24 h of delivery
Indomethacin treatment within 24 h of delivery
** While there appears to be a benefit of delayed cord clamping for premature infants, the most recent RCT and subsequent analysis does NOT show clear benefit in reducing the risk for IVH
What is the most common congenital posterior fossa malformation?
Dandy Walker Malformation
- Agenesis or hypoplasia of the cerebellar vermis
- Cystic dilation of the 4th ventricle
- Enlargement of the posterior fossa
- Associated with hydrocephalus
- Increased risk of motor and cognitive delays

Most common hemisphere to be affected with term focal or multi focal ischemia? Which artery MC involved?
Left hemisphere
Left MCA
How does Periventricular hemorrhagic infarction occur?
Hemorrhagic necrosis of PV white matter related to IVH. IVH obstructs blood flow in terminal vein leading to venous infarction.
Peak ~4 days of life
Risk factors predispose premies to PVL
- Periventricular vascular anatomic factors
- Cerebral perfusion pressure depends on systemic BP
- Increased vulnerability periventricular glial cells
- Insult leading to oligodendroglia cell death and myelin deficiency
Pattern of hypoglycemic injury on MRI?
Related to duration rather than severity of hypoglycemia
Involves bilateral posterior occipital cortex. Middle cerebral infarction and basal ganglia/thalamus abnormalities
How does EPO play a role in HIE?
Prevents NMDA receptor activation 2/2 hypoxia ischemia
Decreases excitotoxicity, apoptosis, cytokines
Decreases peroxinitrite production and oxidative stress
The effect of hypoglycemia on MRI
Corticospinal tract injury
- basal ganglia and thalamus abnormalities
- not how low - import how long (duration)?
Neonates with congenital myotonic dystrophy at highest risk for?
GI dysfunction
Resp dysfunction/hypotonia
Endocrinopathies-hypothyroidism and hyperparathyroid
Adults risk for fatal arrhythmias
Hypotonic, arreflexic neonate with resp distress, nerve biopsy shows decrease in myelin density with onion bulb formation. Dx?
Dejerine Sottas disease
Can also have arthrogryposis and foot deformity, decrease fetal movement IUGR
Marked decreased nerve conduction velocity <12m/sec
Nerve biopsy differentiates from congenital hypomyelinating neuropathy which has absence of myelin fibers
MCC of CP in term neonates
HIE
(1-2/1000 term births)
What is the NNT for therapeutic hypothermia with HIE?
NNT ~6
Describe MRI findings of HIE
• Basal Ganglia and Thalami (BGT)
• Particularly susceptible to injury in acute, profound HIE
• Serve as a “relay station” for the brain
• Posterior Limb of the Interior Capsule (PLIC)
• Dense motor pathway running through the BGT
Extremely age-dependent
• Brainstem
• Involved more often in preterms or severe injury
• Cortex and White Matter
May be solely affected in milder HIE
“Watershed” pattern in partial/prolonged HIE
Reasons to MRI with HIE
•Clarify timing/etiology
•Confirm diagnosis
•Aide in prognostication
•Early MRI
•Ideally day 5-21 after injury in term babies
•Diffusion changes present 7-10 days, then
“pseudonormalise”
•Day 8-30 MRI has higher sensitivity for poor outcome,
but lower specificity than day 1-7
•Lactate/NAA on MR Spectroscopy is 91-94% sensitive
MRI Patterns in HIE
• Severity of BGT injury is most predictive of severity of motor impairment.
• Mild = 11% risk of CP, usually mild
• Moderate = 69% risk of CP
• Severe = 98% with CP, usually severe
• Injury to the PLIC most predictive of
walking at age 2.
• Normal = all walk by 2 years
• Equivocal = 67% walk, but after 18 mos
Abnormal = 12% walk
Which is the most common presentation of Arterial ischemic stroke?
• 1:3000 term births
• Nonspecific Presentation
• Seizures most common presenting sign (>75%)
•
~20% of neonates with seizure have stroke
• Lethargy
• Vital sign fluctuation
• Poor feeding
• NOT hemiplegia
Multiple risk factors in setting of transient hypercoagulability of newborn
Thrombophilia evaluation may not be needed in AIS (doesn’t predict who will have recurrence)
MC difficulties motor deficits
1/4 have epilepsy
What are the proposed mechanisms for IVH?
Fragile vessels in germinal matrix
Clinical instability
Fluctuating CBF
-Increases CBF with Impaired auto regulation (bolus, hypercarbia, anemia/hypoglycemia)
-Decrease CBF from hypotension
How does Grade IV IVH develop?
GM hemorrhage leads to periventricular venous congestion.
This leads to PV ischemia which can lead to periventricular infarction
Antenatal strategies to prevent IVH?
Betamethasone
Magnesium sulfate
Maternal transfer to center who routinely care for VLBW/ELBW
EEG findings of burst suppression
Ohtaharra syndrome
Non ketotic hyperglycinemia
Complication of endoscopic third ventriculostomy with choroid plexus ablation in infant with hydrocephalus?
Diabetes insipidus
Likely related to hypothalamus injury
Tx: water replacement, ADH
B/l vocal cord paralysis is associated with which conditon?
Arnold Chiari II
Which strategies have decreased the risk of IVH?
Antenatal corticosteroids
Delayed cord clamping
Cranial nerves involved in gag reflex
9 and 10
MOA of benzodiazepines
Enhances GABA action–benzo binds GABA-receptor
GABA is inhibitory normally, but in preemies is actually excitatory
Describe anomalies in goldenhar syndrome
Oculoauriculo vertebral syndrome
Ear Tag on tragus
Name associated findings with Meckel Gruber syndrome?
Occipital encephalocele
Polydactyl
Cystic dysplastic kidneys
Leads to ciliary dysfunction
AR
