Flashcards in Neurology Deck (83):
What is the visual acuity of term infants and when does it approach adult levels (20/20)?
Visual acuity in term infants approximates 20/150 and reaches the adult level of 20/20 by about 6 mo of age
Characterized by ipsilateral ptosis (droopy eyelid), miosis (constricted pupil), and anhidrosis (lack of sweating) of the face
Characterized by an initial resistance to passive movement, followed by a sudden release, referred to as the clasp-knife phenomenon
- Abnormalities of tone include spasticity, rigidity, and hypotonia
- results from upper motor neuron dysfunction
- tends to occur in conjunction with disuse atrophy
Seen with lesions of the basal ganglia, characterized by resistance to passive movement that is equal in the flexors and extensors regardless of the velocity of movement (lead pipe)
abnormally diminished tone and is the most common abnormality of tone in neurologically compromised neonates
At what age is clonus not a pathologic sign in a pediatric patient?
in patients <3 mos old, 5-10 beats of clonus may be observed, symmetrically
- sustained clonus is always pathologic
Primitive reflex elicited by supporting the infant in a semierect position and then allowing his or her head to fall backwards onto the examiner's hand
- normal response consists of symmetric extension and abduction of the fingers and upper extremities, followed by flexion of the upper extremities and an audible cry.
- onset: 28-32 wks
- fully developed: 37 wks
- duration: 5-6 mos
- Absence: suggests significant dysfunction of the CNS
- asymmetry: fractured clavicle, brachial plexus injury or hemiparesis
Primitive response elicited by placing a finger in the open palm of each hand; by 37 wk of gestation, the reflex is strong enough that the examiner can lift the infant from the bed with gentle traction
onset: 28 wks
fully developed: 32 wks
duration: 2-3 mos
A primitive reflex produced by manually rotating the infant's head to one side and observing for the characteristic fencing posture (extension of the arm on the side to which the face is rotated and flexion of the contralateral arm)
tonic neck reflex
- abnormal when infant gets stuck in this posture, implies CNS disorder
- onset: 35 wks
- fully developed: 1 mo
- duration: 6-7 mos
Primitive reflex that occurs in slightly older infants, can be evoked by holding the infant's trunk and then suddenly lowering the infant as if he or she were falling. The arms will spontaneously extend to break the infant's fall, making this reflex a prerequisite to walking.
- onset: 7-8 mos
- fully developed: 10-11 mos
- duration: remains throughout life
When does the rooting reflex develop?
onset: 32 wks
fully developed: 36 wks
duration: less prominent after 1 mo
What are the contraindications to performing a lumbar puncture?
suspected mass lesion of the brain/spinal cord
symptoms and signs of impending cerebral herniation in a child with probable meningitis; critical illness (on rare occasions); skin infection at the site of the lumbar puncture; and thrombocytopenia with a platelet count <20 ? 109/L.
The most common form of migraine in both children and adults
migraine without aura
- recurrent (at least 5 attacks)
- lasts 4-72 hrs
- 2 of the ff: unilateral, pulsating, mod-sev pain, aggravated by or cause avoidance of physical activity
- during headache: nausea/vomiting or photophobia/phonophobia
- in children, headaches may be shorter and bilateral
How can one differentiate migraine headache from secondary headache related to increased ICP?
headaches related to increase in ICP tend to be increasing in intensity, usu in early morning upon awakening, occuring almost daily, remits with upright posture
migraine headaches are episodic, not worsening, but when it presents upon awakening, getting up and doing upright activities will make headache and vomiting worse.
What are the indications for neuroimaging in a child with headaches?
Abnormal neuro exam
Focal neurologic signs
Seizures or very brief auras (<6 yr old or any child that cannot adequately describe their headache
Brief cough headache in a child or adolescent
Headache worst on first awakening or that awakens the child from sleep
Migrainous headache in the child with no family history of migraine or its equivalent
What is the imaging of choice for a child with headache, if indicated?
an MRI is the imaging of choice as it provides the highest sensitivity of detecting posterior fossa lesions and does not expose the child to radiation
Two groups of medications for acute migraine attacks
NSAIDs and triptans
- goal of the primary acute medication should be headache relief within 1 hr with return to function in 10 out of 10 headaches
- use NSAIDs first, for only 2-3x/wk then add triptans (almotriptan) for mod-sev attacks
Which antiemetic drugs are very helpful adjuncts in relieving acute migraine headaches because of their mechanism of action (dopamine antagonist) and can be added to the regimen if unresponsive to NSAIDs and triptans?
metoclopramide and prochlorperazine
Preventive therapy for migraine may be done if headaches frequent and disabling. What is the most commonly used preventive therapy for headache and migraine?
- antiepileptic drugs have also been used: topiramate, valproic acid, levetiracetam
seizures that occur between the age of 6 and 60 mo with a temperature of 38C or higher, that are not the result of CNS infection or any metabolic imbalance, and that occur in the absence of a history of prior afebrile seizures
- patients with febrile seizures do not have any increase in incidence of abnormalities of behavior, scholastic performance, neurocognitive function, or attention
Differentiate a simple febrile seizure from complex febrile seizure
simple febrile seizure: generalized, usually tonic-clonic, attack associated with fever, lasting for a maximum of 15 min, and NOT recurrent within a 24-hour period
complex febrile seizure: more prolonged (>15 min), is focal, and/or recurs within 24 hr
What are the major risk factors in recurrence of febrile seizures?
Age < 1 yr
Duration of fever < 24 hr
Minor risk factors:
Family history of febrile seizures
Family history of epilepsy
Complex febrile seizure
Lower serum sodium
Having no risk factors carries a recurrence risk of about 12%; 1 risk factor, 25-50%; 2 risk factors, 50-59%; 3 or more, 73-100%
When is lumbar puncture indicated in a patient with febrile seizure?
Recommended in children below 18 mos because the clinical signs of meningitis may be subtle in this age group
- EEG would not predict the future recurrence of febrile seizures or epilepsy even if the result is abnormal - not routinely done
- blood studies not routinely recommended
- CT or MRI not recommended after first simple febrile seizure
When are apneic episodes in neonates associated with seizures?
When the apnea is accompanied by tachycardia (not bradycardia)
Prolonged expiratory apnea is responsible for the cyanotic episodes, which result from intrapulmonary shunting. An episode starts with a cry and marked pallor, progresses to apnea and cyanosis. Spells usually begin between 6 and 18 mo of age. Syncope, tonic posturing, and even reflex anoxic seizures may follow significant episodes
pallid breath-holding spell
- Often pallid breath-holding spells are made worse by iron deficiency anemia
One of the most common mimickers of generalized tonic clonic seizures and is usually triggered by dehydration, heat, standing for a long time without movement, hot showers, the sight of blood, pain, or sudden stress
Vasovagal (neurocardiogenic) syncope
How can seizures be differentiated from jitteriness?
Jitteriness can be defined as rapid motor activities, such as a tremor or shake, that can be ended by flexion or holding the limb
Seizures do not end with tactile or motor suppression
Starts between the ages of 2 and 12 mo and consists of a triad of infantile spasms that usually occur in clusters (particularly in drowsiness or upon arousal), developmental regression, and a typical EEG picture called hypsarrhythmia
- Many patients start with Ohtahara syndrome, develop West syndrome, and then progress to Lennox-Gastaut syndrome.
usually last 1-2 min and are often preceded by an aura, such as a rising abdominal feeling, d?j? vu or d?j? v?cu, a sense of fear, complex visual hallucinations, micropsia or macropsia (temporal lobe), generalized difficult-to-characterize sensations (frontal lobe), focal sensations (parietal lobe), or simple visual experiences (occipital lobe)
Complex partial seizures
- Subsequent manifestations consist of decreased responsiveness, staring, looking around seemingly purposelessly, and automatisms.
Cafe-au-lait spots are the hallmark of which disease and is present in 100% of patients?
2 types: NF-1 and NF-2
- NF-1 is more common (also known as von Recklinghausen disease)
* Lisch nodules (hamartomas in iris), optic gliomas, neurofibromas (peripheral tumors)
- NF-2 is rare, manifests primarily as congenital bilateral acoustic neuromas (vestibular schwannomas), cafe-au-lait spots less common
* hearing loss, unsteadiness, and sometimes headache or facial weakness
One of the most common complications of NF-1 (neurofibromatosis-1) affecting approximately 30% of children
What is the hallmark of tuberous sclerosis?
- characteristic brain lesion is a cortical tuber
- Brain MRI is the best way of identifying cortical tubers
- most common neurologic manifestations of TSC: epilepsy, cognitive impairment, and autism spectrum disorders
What are the classic dermatological, cardiac, ophthalmologic and pulmonary manifestations of tuberous sclerosis?
derma: hypomelanotic macules, facial angiofibromas, Shagreen patch
cardiac: cardiac rhabdomyoma
ophtha: retinal hamartomas and white depigmented patches
pulmonary: Lymphangioleiomyomatosis (LAM) - classical pulmonary lesion in TSC and only affects women after the age of 20 yr
Sporadic vascular disorder and consists of a constellation of symptoms and signs including a facial capillary malformation (port-wine stain), abnormal blood vessels of the brain (leptomeningeal angioma), and abnormal blood vessels of the eye leading to glaucoma
- incidence of epilepsy in patients with SWS is 75-90%, and seizures develop in most patients in the 1st yr of life
- MRI with contrast is the imaging modality of choice for demonstrating the leptomeningeal angioma in SWS
A clinical syndrome that mimics brain tumors and is characterized by increased intracranial pressure (ICP; >200 mm H2O in infants and >250 mm H2O in children), with a normal cerebrospinal fluid (CSF) cell count and protein content and normal ventricular size, anatomy, and position documented by MRI.
- most frequent symptom is headache; vomiting is rarely as persistent and insidious as that associated with a posterior fossa tumor
- Most patients are alert and lack constitutional symptoms
- (+) MacEwen sign (percussion of the skull produces a resonant sound) due to separation of the cranial sutures
- Papilledema with an enlarged blind spot is the most consistent sign in a child beyond infancy.
Inability to make smooth, accurate, and coordinated movements, usually due to a dysfunction of the cerebellum, its inputs or outputs, sensory pathways in the posterior columns of the spinal cord, or a combination of these
An autosomal recessive condition, is the most common of the degenerative ataxias and is heralded by ataxia beginning at about age 2 yr and progressing to loss of ambulation by adolescence
Movement disorder characterized as habitual, stereotypic movement, vocalization, or behavior that can be temporarily suppressed by the patient
Differentiate dystonia from chorea
Chorea - Fluid, continuous; movements migrate rapidly from one part of the body to another
Dystonia - torsional, sustained muscle contraction, frequently causing twisting and repetitive movements or abnormal postures
How is Tourette Syndrome diagnosed?
(TS) is diagnosed by the presence of multiple motor tics and at least one vocal tic, persisting more or less uninterrupted for 1 year
- a history of discrete, stereotypic movements or vocalizations that can be inhibited by the patient and of disappearance of the movements during sleep supports the diagnosis of tic/TS.
The parents of a 7-year-old boy bring him for evaluation because he has developed a habit of blinking his eyes. This habit has been noted for 3 weeks. Sometimes, he will blink incessantly and, at other times, hardly at all. His habit can be suppressed for up to a minute but not longer. He remains alert and acts normally during the blinking episodes. He does not blink when he is asleep. Other children do not notice his habit of blinking, but his father is very worried and requests that the doctor order an MRI scan to make certain that nothing is wrong with his son's brain.
No other unusual behaviors are reported. However, in retrospect, the parents note that 6 months ago, the child developed a habit of clearing his throat that was attributed to allergy but persisted longer than expected. The child has no history of other significant medical problems. He had one episode of streptococcal pharyngitis 1 year ago that was treated with amoxicillin.
The child is a good student and gets along well with other children but is described as “a worrier.” His maternal aunt was treated for obsessive-compulsive disorder.
Physical examination reveals a high-strung, alert boy in good general health. There are no signs of infection or inflammation in the pharynx, and no adenopathy is noted. The neurological examination reveals no focal deficits. The child frequently and forcefully blinks his eyes and also periodically stretches his neck.
What is your diagnosis?
Tic disorder (Tourette Syndrome)
- Some patients with tics also have a learning disability (LD) that is suggested by a history of poor grades and further suggested by a learning evaluation.
- Tics do not normally result from a brain tumor, any other intracranial lesion, or a degenerative disorder and are usually readily differentiated on clinical grounds from other abnormal movements
What is the most common acquired chorea of childhood, which occurs in 10% to 20% of patients with acute rheumatic fever, typically weeks to months after a group A β-hemolytic streptococcal infection, with peak incidence at age 8 to 9 yr, and a female predominance of 2 : 1?
- clinical hallmarks of SC are chorea, hypotonia, and emotional lability
Very rapid (“lightning-fast”) involuntary movement, most often of the upper extremities, occuring mostly during sleep, cannot be voluntarily suppressed like tics.
Severe rigidity combined with high fever, autonomic symptoms (tachycardia, diaphoresis), delirium, and dystonia
neuroleptic malignant syndrome
Delayed onset involuntary movements that develop in the setting of chronic neuroleptic use, at least 3 mo in duration
In acute drug-induced dystonic movement disorder, what is the drug of choice to rapidly reverse the symptoms, especially the life-threatening ones presenting as laryngospasm and airway compromise?
diphenhydramine (1-2 mg/kg/dose)
Severe rigidity combined with high fever, autonomic symptoms (tachycardia, diaphoresis), delirium, and dystonia which typically occurs a few days after starting or increasing the dose of a neuroleptic drug, or in the setting of withdrawal from a dopaminergic agent.
neuroleptic malignant syndrome (NMS)
- occurs within a month of medication initiation or dose increase, in contrast to acute dystonic rxns which take place within days
- drug of choice: dantrolene
Autosomal recessive inborn error of copper transport characterized by cirrhosis of the liver and degenerative changes in the CNS, particularly the basal ganglia
- copper metabolism
- liver cirrhosis
- CNS (basal ganglia): initial sign is often progressive dystonia
Drug of choice for children with generalized dystonia
anticholinergic agent trihexyphenidyl (Artane)
Apneic and focal motor seizures that start around the fifth day of life
benign idiopathic neonatal seizures (fifth day fits)
Childhood seizure disorder that lasts for only a few seconds, and are accompanied by flutter or upward rolling of the eyes but typically not by automatisms of the complex partial seizure type (absence seizures can have simple automatisms like lip-smacking or picking at clothing and the head can minimally fall forward). Usually starts at 5-8 yr of age and are often, owing to their brevity, overlooked by parents for many months even though they can occur up to hundreds of times per day.
- do not have a postictal period and are characterized by immediate resumption of what the patient was doing before the seizure
- Hyperventilation for 3-5 min can precipitate the seizures and the accompanying 3 Hz spike–and–slow wave discharges
- characterized by loss of language skills in a previously normal child, common in boys; the aphasia may be primarily receptive or expressive, and auditory agnosia may be so severe that the child is oblivious to everyday sounds. Hearing is normal, but behavioral problems, including irritability and poor attention span, are particularly common. Seizure may be focal or generalized tonic-clonic, atypical absence, partial complex, and, occasionally, myoclonic
- Anticonvulsant of choice: valproic acid
Seizure lasting for more than 30 min or recurrent seizure lasting for 30 min from which the patient does not regain consciousness
- although popular definition is recurrent or continuous seizures lasting for at least 30 min, it is recommended to start treatment using status epilepticus protocol when seizures persist for more than 5 minutes
What are the priorities in the management of status epilepticus?
- airway: lateral decubitus position, suction secretions, intubate when indicated (sedate to avoid vasovagal stimulation)
- oxygenate and ventilate
- check NVS
- secure IV access, D50.9 NaCl (except for neonates)
- drug therapy
0-5 min: diazepam (0.3 mg/kg IV), lorazepam IV or rectal diazepam/ buccal midazolam
5-20 min: Pb 20 mg/kg IV, rate 1-2 mg/kg/min, max 800 mg
20-30 min: additional 10 mg/kg Pb if max dose not yet reached
A 15-year-old adolescent male experiences sudden-onset severe weakness of the right leg while playing soccer and collapses to the ground. His right arm is also weak, and his speech is slurred. He is immediately transported to the emergency room.
The patient has no prior history of any medical problems. He has never had a migraine headache or a seizure, and he does not report a headache now. He takes no medication.
He presents as a frightened, healthy-appearing teenager. His blood pressure is 145/87. He does not have a fever. The neck is supple, and no carotid or cranial bruits are noted. The cardiac rhythm and heart sounds are normal. The patient's
speech is slurred but intelligible, and he follows directions well. The visual fields are full to confrontation. The pupils are equal and reactive, and the extraocular movements are intact. Facial, tongue, and palatal movements are symmetrical. Motor examination reveals decreased tone on the right side, a positive pronator drift test, slow fine finger movements, 4/5 strength in the upper extremity, and 3/5 strength in the lower extremity. Motor examination of the left upper and left lower extremity is normal. The deep tendon reflexes are diminished on the right side, and the right toe does not move in response to plantar stimulation.
A CT scan of the head reveals no evidence of bleeding or any other intracranial abnormality.
What is your diagnosis?
Acute ischemic stroke
- disorders of the cerebral arteries and has emerged as the leading cause of childhood AIS, present in >50% of children
- 3 types of etiology: arteriopathic, cardiac, hematologic
What are the 3 basic guidelines in the treatment of acute ischemic stroke?
Antithrombotic strategies: anticoagulation
Neuroprotective strategies: control of blood glucose, temperature, and seizures and aggressive maintenance of cerebral perfusion pressure
Secondary stroke prevention: antiplatelet therapy
What is the leading cause of term-born cerebral palsy (congenital hemiplegia)?
A group of permanent disorders of movement and posture causing activity limitation, that are attributed to nonprogressive disturbances in the in the developing fetal or infant brain
What are the major lesions that contribute to CP in very premature infants weighing <1000 g?
intracerebral hemorrhage and periventricular leukomalacia (PVL)
What is the first clinical indication of spastic diplegia in a child?
The 1st clinical indication of spastic diplegia is often noted when an affected infant begins to crawl. The child uses the arms in a normal reciprocal fashion but tends to drag the legs behind more as a rudder (commando crawl) rather than using the normal four-limbed crawling movement
- spastic legs with brisk reflexes, ankle clonus, and a bilateral Babinski sign
What is most common neuropathologic finding in children with spastic diplegia?
- visualized on MRI in more than 70% of cases
The most severe form of CP because of marked motor impairment of all extremities and the high association with mental retardation and seizures
Which disease causes prominent dystonia that can resemble CP but with normal MRI?
dihydroxyphenylalanine (DOPA)-responsive dystonia (Segawa disease)
- diurnal variation in their signs with worsening dystonia in the legs during the day
- These patients can be tested for a response to small doses of l-dopa and/or cerebrospinal fluid can be sent for neurotransmitter analysis
Which type of CP is associated with kernicterus?
What is the diagnostic study of choice essential in the diagnosis of spinal cord tumors, especially intramedullary spinal cord tumors?
MRI with and without gadolinium enhancement of the spinal cord
Cystic distension of the spinal cord caused by obstruction of the flow of spinal fluid from within the spinal cord to its point of absorption.
- classic presentation is the central cord syndrome. In this situation the patient develops numbness beginning in the shoulder in a capelike distribution followed by the development of atrophy and weakness in the upper extremities.
What is the most common cause of bacterial meningitis in children 1 mo to 12 yr of age?
Give the normal values of CSF findings
pressure: 50-80 mm H2O
leukocytes: 50 mg/dL (or 75% of serum glucose)
What are the clinical signs of meningeal irritation?
Meningeal irritation is manifested as nuchal rigidity, back pain, Kernig sign (flexion of the hip 90 degrees with subsequent pain with extension of the leg), and Brudzinski sign (involuntary flexion of the knees and hips after passive flexion of the neck while supine)
What are the signs of increased ICP?
Increased ICP is suggested by headache, emesis, bulging fontanel or diastasis (widening) of the sutures, oculomotor (anisocoria, ptosis) or abducens nerve paralysis, hypertension with bradycardia, apnea or hyperventilation, decorticate or decerebrate posturing, stupor, coma, or signs of herniation.
What are the contraindications for an immediate LP?
1) evidence of increased ICP (other than a bulging fontanel), such as 3rd or 6th cranial nerve palsy with a depressed level of consciousness, or hypertension and bradycardia with respiratory abnormalities
2) severe cardiopulmonary compromise requiring prompt resuscitative measures for shock or in patients in whom positioning for the LP would further compromise cardiopulmonary function; and
3) infection of the skin overlying the site of the LP.
Thrombocytopenia is a relative contraindication for LP. If an LP is delayed, empirical antibiotic therapy should be initiated.
The most common sequela of bacterial meningitis and, usually, is already present at the time of initial presentation
sensorineural hearing loss
- The most common neurologic sequelae include hearing loss, mental retardation, recurrent seizures, delay in acquisition of language, visual impairment, and behavioral problems
What is the most common etiology of viral meningoencephalitis?
What is the usual treatment regimen for brain abscess?
MCV (metronidazole + 3rd gen ceph (cefta/ceftri) + vancomycin)
- if etiology is cyanotic CHD: ampi-sul or (3rd gen ceph + metro)
When is surgical excision of a brain abscess indicated?
when the abscess is >2.5 cm in diameter, gas is present in the abscess, the lesion is multiloculated, the lesion is located in the posterior fossa, or a fungus is identified
progressive hydrocephalus with a myelomeningocele
type II Chiari malformation
Cystic expansion of the 4th ventricle in the posterior fossa and midline cerebellar hypoplasia, which results from a developmental failure of the roof of the 4th ventricle during embryogenesis. Infants present with a rapid increase in head size and a prominent occiput. Transillumination of the skull may be positive. Most children have evidence of long-tract signs, cerebellar ataxia, and delayed motor and cognitive milestones, probably due to the associated structural anomalies.
Dandy Walker malformation
Patient presents with gradual onset of weakness beginning in the lower extremities and progressively involving the trunk, the upper limbs, and finally the bulbar muscles. This was preceded by 10 days of nonspecific viral infection. Proximal and distal muscles are noted to be symmetrically involved. Patient was noted to be irritable. Weakness was noted to progress to inability or refusal to walk and later to flaccid tetraplegia.
What is your diagnosis?
- pattern of weakness described is called Landry ascending paralysis
- in cases with an abrupt onset, tenderness on palpation and pain in muscles is common in the initial stages
- affected children are irritable; paresthesias can also occur
- implicated preceding infections: Campylobacter, Helicobacter, Mycoplasma
- Dx: CSF studies (high protein, low WBC, normal glucose)
- Tx: IVIG
In patients with GBS what are the impending signs of respiratory failure?
dysphagia and facial weakness
-3 clinical features are predictive of poor outcome with sequelae: cranial nerve involvement, intubation, and maximum disability at the time of presentation
In the diagnosis of GBS, CSF studies are essential. What is the classic CSF picture in GBS?
CSF protein is elevated to more than twice the upper limit of normal, glucose level is normal, and there is no pleocytosis. >10 WBCs/mm3 are found.
- The dissociation between high CSF protein and a lack of cellular response in a patient with an acute or subacute polyneuropathy is diagnostic of Guillain-Barre syndrome.
- Tx: IVIG
chronic disease characterized by rapid fatigability of striated muscle
What are the signs and symptoms of cerebral herniation? Describe how this can be prevented.
pupillary dilatation, systemic hypertension, bradycardia, extensor posturing
hyperventilation with an Fio2 of 1.0,
intubating doses of either thiopental or pentobarbital and
either mannitol (0.25-1.0 g/kg, IV) or hypertonic saline (3% solution, 5-10 mL/kg IV)