Neurology and optho Flashcards
What is the most common brachial plexus injury in neonates?
upper trunk (C5-C7), Erb’s palsy, accounts for 90%; biceops relfex absent but intact palmar grasp, arm adducted and iternally rotated, extension of the elbow, pronation of the forearm, flexed wrist and fingers
What is the most common condition that is misdiagnosed as neonatal seizures?
benign sleep myoclonus; characterized by sudden jerk of oone or more limbs, can be unilateral or bilateral; primary feature is that they occur during sleep and stop on arousal
Is the 2 channel aEEG superior to the single channel aEEG for detecting focal seizures?
yes
What is the most common cause of conjunctivitis in the first month of life?
Chlamydia
What is a common cause for conductive hearing loss?
fluid in the middle ear
What disorders are associated with a problem during primary neurulation (3-4 weeks gestation?)
dorsa induction: anencephaly, myeloschisis, encephalocole, myelomeningocoele, Arnold-Chiari malformatio, (problems with brain and spinal cord except the lower segment)
At what gestation can the elbow be adducted all the way the opposite shoulder?
28 weeks
Which neurodevelopmental sequelae is most likely associated with IUGR instead of prematurity?
decreased full scale and Verbal IQ ( in the case of infant that is both preterm and IUGR)
what are the strongest risk factors for hearing loss?
asphyxia, craniofacial anomalies, and diagnosis of a syndrome wih hearing loss
what is th most common cause of hearing loss?
genetic (50%), acquired 25% and unknown 25%
What is the common genetic cause of hearing loss?
mutation in the connexin 26 gene (CX26) gene which causes 20-30% of hearing loss
What syndromes are asociated with hearing loss?
Alport syndrome, Peirre Robin sequence, Usher syndrome, Pendred syndrome, Waardenburg syndrome, Treacher collins syndrome, CHARGE association, Klippel Feil sequence, trisomy 8, Stickler syndrome, trisomy 21
An infant that is 12 days old presents with bilateral leucoria, jaundice, and hepatomegaly. He is hypotensive, tachycardic and tachypneic. His blood culture become positive for E coli sepsis. Wht is the most likely diagnosis
galactosemia
Infant with subgaleal hemorrhage. Where is the site of bleeding?
bleeding from emissary veins betwwen the scalp and the dural sinuses; accumulatio of blood in the subcutaneous tissue between the skull and aponeurosis
Rupture of vessels in the subperiosteal space leads to what ?
cephalohematoma; can lead to skull deformation if the lesion is calcified or ossified
This kind of bleed is causesd by a disruption of the middle cerebral artery or vein and venous sinuses; characterized by subperiosteal bleeding in the inner surface of the skull
extradural hemorrhage
What is the most common cause of seizures in the neonatal period?
HIE
What are the hemodynamic changes the predispose preterm neonates to a peri/intraventicular cranial hemorrahge?
decreased compliance of the immature myocardium, impaired myocardial contractility, low cerebral blood flow on day 1 of life, shunting through the PDA
What are the causes of primary microcephaly?
Chromosomal anomalies (T13, T18, T21); somatic anomalies like Rubinstein-Taybi syndrome, PWS, Smith-Lemli-Opitz; neuralation anomalies like anenecephaly; cleavage syndromes like holoprosencephaly; migratonal anomalies like schizencaphaly, lissencephaly, polymicrogyria; congenital infections- toxoplasmosis, rubella, CMV, HSV, coxsackie; biochemical disorders like maternal DM or maternal PKU; toxins like maternal cocaine, alcohol, phenytoin
Are most cases of retinoblastoma hereditary or nonhereditary?
nonhereditary; 40% of cases are hereditary and are auto dom
How do you diagnose fetal ventriculomegaly?
when the atrial wdth of the at least one of the lateral ventricles is >10 mm.
what is a common cause of unilateral corneal clouding?
birth trauma, especially with a forceps delivery. The clouding results from Descemet membrane tears which are commonly vertically or obliquely oriented.
What increases cerebral blood flow?
increased BP in asphyxiated infant; increased paCO2, decreased paO2, dopamine, decreased hemoglobin concentration, increased proportion of fetal hemoglobin, hypoglycemia; seizures
what causes decreased cerebral blood flow?
decreased paCO2, increased paO2, increased hemoglobin concentration, decreased fetal hemoglobin
True or false: with decreasing gestationala age, the MAP approaches the lower limit of autoregulation plateau which predisposes the premature brain to decreased cerebral blood flow with changes in BP
TRUE
Describe Dandy-Walker malformation
Developmental anomaly of the cerebellar vermis leading for faillure of the 4th ventricle to close normally. The three classic findings are: vermis hypoplasia, cystic dilation of the posterior fosaa with communication to the 4th ventricle and abnormally high tentorum and torcula. Dandy-Walker - think cyst and small cerebellum
Descibe Arnold Chiari Malformation
Downward displacement of the cerebellum into the spinal cord. Posterior fossa is generally small. Wide specturm of clinical symptoms : obstructive hydrocephalus, abnml eye movements, cerebellar deficits and myelomeningocoles
What is the most common posterior fossa malformation
Dandy-Walker
What is the second most common lethal autosomal recessive disease in Caucasians?
Spinal muscular atrophy, (first is CF)
Name the 3 peripheral neuropathies a/w Leukodystrophies, the inheritance, and the enzyme defect
All AR: Krabbe’s diseaase due to Galactosylceramide beta-galactocerebroside deficiency; Metachromaic leukodystrophy due to arylsulfatase A def; Neonatal Adrenoleukodystrophy –> elevated VLCFA
A well 6 mo infant develops constipation, weak cry, hypotonia, and weakness. On physical exam, there is ptosis, dilated pupils and EOM abnormal. Whats the Dx?
infantile botulism
Seizures due to the following causes happen at what time frame? Meningitis/sepsis, drug effects, HIE, intrauterine infectin, IVH at term, laceration of tentorium or falx, pyridoxine deficiency, subarachnoid hemorrage
peak onset at 24 hours
What are the causes for seizures that happen at 24-72 hours of life?
cerebral contusion/dysgenesis/ infarction/ hemorrhage, drug withdrawal, meningitis/sepsis, metabolic disturbances, neurocutaneous syndromes, pyridoxine def, urea cycle defects
What are the cause of sezures that happen between 72 hrs of life and 1 week?
cerebral dysgenesis/infarction, familial neonatal seizures, Hypopit, Intracranial hemorrage, Kernicterus, Methylmalonic aciduria, propionic aciduria, tuberous sclerosis, Urea cycle defects
What are the causes of seiures that occur between 1-4 weeks?
Cerebral dysgenesis, cerebral venous infarction, fructose dysmetabolism, Gaucher’s disease type 2, GM! Gangliosidosis type 1, herpes encephalitis, Ketotic hyperglycinemia, MSUD,Neonatal adrenoleukodystrophy, Neurotransmitter defects, Tuberous sclerosis and Urea cycle defects
What defects are due to a problem during primary. Neurulation (happens at weeks 3-4)?
anencephaly, myeloschisis, encephalocoele, myelomeningocele, Arnold-Chairi malformation
What defects are due to a problem during secondary neurulation (weeks 4-7)?
spinal cysts, tethered cord, lipoma, teratoma, myelocystocoele, meningocele-lipomeningocoele
Aprosencephaly happens during what stage of CNS development?
abnormal development during the prosencephalic stage in which there is absence of the telencephalon, and diencephalon with porencephalic remnant. Happens at 2-3 months
What the pathophysiology of holoproscenephaly?
abnormal development during the prosencephalic stage in which there is a primary defects of cleavage
In what stage of neurulation does agenesis of the corpus callosum occur?
prosenecephalic phase, primary defect in cleavage
in primary and secondary neurulation, what is the direction of induction?
dorsal
In prosencephalic stage of neurulation, what is the direction of induction?
ventral
At what stage in neurulation does microcephaly and macrocephaly occur>
neural and glial proliferation at 3-4 months
Name disorders that happen duri ng neuronal migration from 3-5 months GA
schizencephaly, lissencephaly, pachgyria (broad gyri) and polymicrogyria
What are disorders of neuonal organization?
mental deficiency, T21, Fragile X, austism, Angelman syndrome, prematurity
What is the last pathway in the brain myelinate?
the association bundle, which connects the prefrontal cortex with the temporal and parietal lobes. Happens at ~32 years
Failure of anterior closure of the of the neural tube causes what problem with brain development?
anencephaly
what defect is caused by failure of rostal closure of the neural tube resulting in herniation of the meniniges and brain tissue through a skull defect
encephalocoele; seen in Meckel-Gruber syndrome’
What is the most common location of encephaleocoles>
occipital (70%) followed by frontal, then parietal or nasofrontal
What results from failure of closure of the posterior neural tube?
myelomeningocoele
At what spinal level do 80% of myelomeningocoeles occur?
lumbar area because it is the last to close
Caudal displacement of the cerebellar tonsils before the foramen magnum and the 4th ventricle is always in normal position, a/w hydromelia and or other skeletal anomalies (scoliosis most commonly)
Arnold Chiari type 1
elongation and caudal displacemnet of the cerebellar tonsils, 4th ventricle, choroid plexus, and medulla. This abnormality will descend into the cervial spinal canal and is often a/w hydrocephalus
Arnold Chiari type 2
cervical meningocoele yet with displacement of the cerebellum and lower brainstem into the sac
Arnold Chiari type 3
What is the difference between anencephaly and aprosencehaly on exam?
both have minimal cranial volume but in aprosencephaly, will have inact skull, hair, dermal coverings where in anecephaly, there is an absence of a large part of the skull with an absent scalp over the skull abnormality. Also may have cyclopia with aprosencephaly
At what stage in neurulation does septo-optic dysplacia occur?
prosenecephalic phase, problem with midlin development
What other diseases are a/w agenesis of the corpus collasum?
Neurologic malformations ( Dandy-walker, holoproscencephaly,: facial anomalies, CHD, metabolic disorders (non-ketotic hyerglycinemia, pyruvate dehydrogenase def), intrauterine infections, T8, T13 , T18
What is a/w macrocephaly?
benign familial macrocephaly (~50%, AD, M>F), BWS, neurofibromatosis, Soto syndrome, Fragile X, achondroplasia
What is the most common craniosynostosis?
scaphocephaly or dolicocephaly; ~50%; normal intelligence, surgery for cosmesis
What is the second most common craniosynostosis?
fronal plagiocephaly= premature closure of unilateral coronal suture; a/w Crouzon and Apert, a/w developmental and mental deficiency, early correction to prevent neurological sequela
This craniosynostosis is a/w Carpenter sydrome
brachicephaly, premature closure of the bilateral coronal sutures
hypsarrythmia after 2 months of age on EEG
infantile myoclonic spasms
True or false: A normal neuro exam and and a normal EEG after 1 week is a/w a normal outcome
TRUE
What is the most common clinical sequela of PVL?
spastic diplegia (lower extremities more affect than upper extremities)
This diagnosis is confirmed with pupil constriction in response to metacholine eye drops or pilocarpine and no skin flare with intradermal histamine injection
Riley-Dat syndrome, AR, seen in Ashkenazi jews, aka Familial dysautonomia
classic clinical triad:hypotonia, cryptorchidism/hypogonadism, and poor feeding
PWS
cranial bruit + CHF- name the Dx
Vein of Galen malformation
What syndromes and infections are a/w congenital glaucoma?
Sturge- Weber (most commone), NF, retinoblastoma, homocystinuria, T21, congenial rubella, Stickler syndrome and long term exposure to steroids
What is the most common cause of congenital cataracts with hearing impairment?
Rubella; CMV and toxo have hearing impairment but have chorioretinitis
which stage of language development typically begins by 5-7 momths and if not present by 11 months of age suggests a hearing deficit?
babbling
When do you consider cochlear implants?
infants with >/= 85 dB hearing impairment who have not benefited from a several month period of amplicatipn and intensive speech and language therapy
hypotonia, weakness, mild contractures of the large joints, absent DTR, and tongue fasiculations are seen in a 2 day old infant. Dx?
SMA type 1 ak Werdnig-Hoffman disease
what is the clinical presentation for an infant with focal cerebral weakness?
contralateral hemiparesis, eye deviation to the side of the lesion, full term infant will have weakness in the upper>lower extermities, preterm infants will have weakness in the lower>upper extremity
What is th clinical presentation for an infant with parasaggital cerebal injury?
weakness in the proximal limbs, upper> lower extremities; this is mostly an ischemic lesion in full term neonates
What is the clincal presentation for an infant with periventricular cerebral injury that is bilateral?
symmetric weakness, lower>upper extremity
What is the clinical presentation for an infant with a spinal cord injury?
intitial flaccid weakness in all extremities with facial sparing, evolving to spasticity in weeks to months
This reflex appears by 28-32 weeks, established by 37 weeks and disappers by 6 months
moro reflex
this reflex is one of the earliest reflexes, appears at 28 weeks, established by 32 and disappears by 6 months
palmar grasp
this reflex appears at 35 weeks, established by 1-2 months and disappers by 6 months
tonic neck; persistence of this reflex may suggest focal cerebral abnormalities
this reflex is absent at 26 weeks, complete by 34 weeks, and disappears by 7-8 months
crossed adductor reflex
this reflex is absent prior to 29 weeks, present at 32-34 weeks
pupillary light reflex
What is the most common cause of obstructive hydrocephalus?
IVH (post hemorrhagic hydrocephalus); next is aquaductal stenosis
what kind of hydrocephalus is seen in patients with Dandy Walker?
obstructive
What kind of hydrocephalus is seen in patients with Arnold Chiari?
communicating
What is the most common injury after HIE?
selective neuronal necrosis
What is the distribution of selective neuronal necrosis?
- diffuse, 2. cerebral cortex-deep nuclear structures, 3. deep nuclear structures (basal ganglia, thalamus, globus pallodus)
What is the cause of parasagitall cerebral injury?
disturbance in cerebral perfusion secondary to systemic hypotension, hypoxemia, acidosis (2/2 severe perinatal depression)
What is the most common site for focal or multi-focal ischemia?
Left hemisphere (3x more likely), Left MCA most common, followed by R; clinically, MCA infarcts will affect the arms > legs, manifesting as weakness
This is caused by hemorrhagic necrosis of the periventricular white matter and is directly relatedd to IVH
periventricular hemorrhage infarction; lesion is on the same side as IVH, ~80% are a/w large asymmetric IVH, develops after IVH b/c IVH obsructs blood flow in the terminal vein, leading to venous infarctin in the distribution of the medullary veins ( drain the cerebral white amtter into the terminal vein)
What is the most freuquent kind of intracranial hemorrhage?
subarachnoid; more common in preterm infants, often aymptomatic, good prognosis
What is the most common site for brachial plexus injury
Right side, 90% unilateral, start to recover by 2 weeks with full recovery by 4-6 months; 90% are C5-C7 (Erb-Duchenne)
What is the most common cranial nerve injured during birth and what side is usually affected?
unilaterl facial nerve palsy, L side; recovers in 1-3 weeks
EMG findings with non-specific denervation, fasiculations, and fibrillatians; muscle biopsy shows atrophy of motor units
SMA type 1 ak Werdnig-Hoffman disease
EMG shows progressive decline in amplitude with repetitive nerve stimulation; normal muscle biopsy and normal nerve conduction velocities
Acquired transient neonatal myasthenia gravis; these findingd are also seen in congenital form
EMG shows “myotonic changes eliciting a “dive-bomber” sound; abnormal muslce biopsy showing small round muscle fibers with large nuclei and sparse myofibrls, normal nerve conduction velocity
congenital myotonic dystrophy
poor muscle tone, arthrygryposis, tent shaped mouth, presenting in the first few hours or days
congenital myotonic dystrophy: AD, due to expanded CTG repeats, with severity determied by the number of repeats
What is the most common type of CP seen due to extreme prematurity?
spastic diplegia
this type of CP is characterized by mixed muscle tone in the same muscle with both gross motor and fine motor function affected, normal cognition; persistence of the palmar grasp
athetoid CP (seem with bilirubin encephalopathy);
What are the most identifiable causes of severe mental deficiency in the US?
FAS, fragile X, T21
What is the best predictor of cognitive development?
language development
This type of hearing loss has good bone conduction but poor air conduction
conductive hearing loss
This kind of hearing loss results from abnormal processing of sound signal from the cochlea to the auditory nerve. Children will have more severe sound and speech abnormalities than predicted for their degree of hearing loss
auditory dyssynchrony
What diagnoses are a/w auditory dyssynchrony?
prematurity, indirect hyperbili, hypoxia, immune disorders, familial
This hearing test is more likely to be affected by debris or fluid in the external and/or middle ear and thus has higher referral rates. It is also not able to detect some forms of sensorineural hearing loss
OAE
What is the preferred screening test for NICU babies?
ABR because it can detect auditory dyssynchrony
How is a learning disability diagnosed?
at least 1 SD or 15 point difference between the scores on a standard intelligence test (higher) and a standard acheivement test (lower)
When is optic nerve myelination complete?
24 months
when do visual evoked potentials reach adult levels?
6 months
when does an infant have conjugate horizontal gaze with visual fixation?
at term GA
when does an infant have conjugate vertical gaze?
2 months
An infant with ROP has a high likelihood of developing this visual defect later in life
strabismus
True or false: Diffuse PVL is the most common form of brain injury in preterm infants and is the majoe cause of cognitive deficits and long tern neurodevelopmental impairment in this population.
TRUE
When should ROP screening occur?
all infants below 32 weeks and or BW < 1500, at 4-6 weeks of life or 31-32 weeks, whichever comes later
excessive tearing, corneal cloudiness and dampened pupillary light reflex are all signs of ?
congenital glaucoma; it is AR and more common in boys
After the neonatal period, infants may have secondary glaucoma. List the potential causes
homocytinuria, congenital rubella syndrome, ROP, syndromes (Stickler, Sturge-Weber)
What are risk factors for IVH?
shorter gestation, male, surf def, hypercapnia, PTX, fluctuating arterial BP, and early hypotension
What is the most common region of the brain affected by PVL?
periventricular white matter dorsolateral to the external anbgles of the lateral ventricles
What is the pathogenesis behind PVL?
oligodendrocyte progenitor cells present in the periventricular area that are especially susceptible to free radial injury; poor vascular supply to the periventricular white matter
up to what age is 5-10 beats of clonus normal?
3 months
With HIE, is there more injury to white matter or gray matter?
white matter
When is C-section indicated for myelomeningocoele?
infant is breech or has macroencephaly
This reflex appears 32 weeks and is gone by 1-2 months.
stepping reflex
How to preterm infant with IUGR compared to AGA preterms in neurodevelopmental outcome?
preterm IUGR infants had lower full scale and verbal IQ sores than controls. Both preterm with and without IUGR have similarly higher rates of behavioral difficulties than term infants indicating that IUGR is not an additional risk factor for those outcomes
bleeding from emissaty veins between the scalp and the dural sinuses describes what kind of extracranial hemorrhage?
subgaleal
What atrial width of the intracranial ventricles is considered ventriculomegaly?
> 10 mm
In cases of inherited Retinoblastoma, what is the inheritance pattern and the genetic mutation?
auto dom; retinoblastoma is initiated by the inactiviation of both allelles of the RB 1 gene
What is the sequence of events that leads to hypoxic brain injury?
cerebral tissue hypooxia
