Practice RITE Flashcards
parasympathetic nervous system governs
pupil constriction, bronchoconstriction, detrusor contraction and sphincter relaxation, and penile erections.
orbitofrontal syndrome consists of
socially inappropriate behaviors as well as poor impulse control with disinhibition
lateral convexity syndrome is associated with
dysexecutive symptoms
mesial frontal syndrome is associated with
amotivation.
combination of optic nerve dysfunction and ocular motility deficits localizes to the
orbital apex.
Cortical areas critical for gait include the
medial frontal region, the paracentral lobule, and the supplementary motor cortex.
Fifty patients with elevations of serum cardiac troponin levels had strokes involving the
right posterior, superior medial insula, and the right inferior parietal lobule
biceps are innervated by the _______ nerve, which arises from the ______ cord of the brachial plexus
musculocutaneous, lateral
pronator teres is innervated by the _____ nerve from axons that travelled in the _____ cord of the brachial plexus
median, lateral
deltoid is innervated by the _____ axillary nerve, which arises from the _____ cord of the brachial plexus
axillary, posterior
brachioradialis is innervated by the _____ nerve, which arises from the _____ cord of the brachial plexus.
radial, posterior
rhomboid receives supply directly from the _____
C5 root
supraspinatus is innervated by the ______ nerve, which arises from the _____ trunk of the brachial plexus.
suprascapular, upper
This serve as the primary input nuclei for the basal ganglia
caudate and the putamen
The ________, which projects to the ventral anterior nucleus of the thalamus, is the primary output nucleus.
globus pallidus
_______, located in the midbrain, sends dopaminergic fibers to the putamen.
substantia nigra pars compacta
_______ receives inhibitory input from the external part of the globus pallidus and sends excitatory input to the globus pallidus pars interna.
subthalamic nucleus
In ischemic third nerve palsies, the pupil is typically spared, as is the periphery of the nerve, where the _________ fibers course.
pupillomotor
_______ aneurysms typically cause third nerve palsies involving the pupil, as they compress the nerve, and therefore the peripheral pupillomotor fibers
posterior communicating artery
“one-and-a-half” syndrome in which the
ipsilateral eye has no horizontal movements and the contralateral eye is only able to abduct.
“one-and-a-half” syndrome
combination of a left intranuclear ophthalmoplegia (which prevents the left eye from adducting on rightward gaze with end-gaze nystagmus of the abducting right eye) and a left abducens nuclear palsy (which produces an ipsilateral gaze palsy preventing the patient from looking left).
“one-and-a-half” syndrome lesion
This lesion must involve the left medial longitudinal fasciculus and left abducens nucleus.
When the eye is abducted, the primary depressor is the
inferior rectus
eye is adducted, the
superior oblique and inferior rectus depress the eye.
When the patient looks down and to the left, she is primarily using the
right superior oblique and left inferior rectus.
Cheiro-Oral Syndrome is a lacunar syndrome characterized by contralateral sensory deficits of the mouth and hand.
It typically localizes to the VPM and VPL in the thalamus.
ipsilateral side of a spinal cord hemisection there would be an upper motor neuron syndrome, greatly impaired discriminatory tactile sense, and reduced muscle tone below the level of the lesion.
Contralateral to the lesion there would be loss of pain and temperature due to interruption of the ascending spinothalamic tracts (which cross soon after entry)
short head of the biceps femoris is the only muscle proximal to the knee innervated by the peroneal division of the sciatic nerve.
Needle EMG abnormalities of this muscle would indicate that a lesion of the peroneal nerve would have to be proximal to the fibular head.
Auditory fibers from the superior olivary nucleus ascend in the lateral lemniscus to reach the inferior colliculus.
The electrical activation of the lateral lemniscus is reflected in wave 4 of a brainstem auditory evoked potential.
fibers in the trapezoid body arise from the
ventral cochlear or the superior olivary nucleus and decussate to the contralateral side.
Palatal myoclonus or palatal tremor is characterized by rhythmic jerking movements of the palate and pharyngeal structures that persist during sleep.
It is associated with lesions that interrupt the dentato-rubro-olivary pathway, also known as the Guillain-Mollaret triangle.
Guillain-Mollaret triangle.
triangle begins in the inferior olive, which projects via the inferior cerebellar peduncle to the contralateral dentate nucleus.
dentate nucleus projects via the
superior cerebellar peduncle to the ipsilateral red nucleus.
ipsilateral red nucleus completes the triangle by projecting to the ipsilateral inferior olive via the central segmental tract.
This patient’s dysarthria is likely caused by involvement of the nucleus ambiguous which provides axons to both the glossopharyngeal and vagus nerves
Fibers carrying information from the superior temporal visual field briefly bend up into the
contralateral optic nerve (Willebrand’s Knee).
lesion of the optic nerve as it joins the optic chiasm therefore interrupts all the fibers from the ipsilateral eye as well as the crossing fibers from the contralateral superior temporal visual field.
This would cause the complete vision loss on the right and the left temporal hemianopsia.
superior gluteal nerve innervates tensor fascia latae, as well as gluteus medius and minimus.
The superior gluteal nerve arises from the lumbosacral plexus.
tensor fascia latae is primarily an L5-innervated muscle and thus clinical weakness or denervation on EMG of the tensor fascia latae can be used to exclude a
lesion distal to the lumbosacral plexus, such as a sciatic neuropathy.
lateral inferior or caudal pontine syndrome due to occlusion of the anterior inferior cerebellar artery (AICA syndrome) involves lesions in the fascicles of cranial nerve VII, the spinal tract, and nucleus of cranial nerve V, the lateral spinal thalamic tract, descending sympathetic fibers (lateral reticular nucleus), the middle cerebellar peduncle, the inferior surface of the cerebellum, and in addition, the inner ear and cochlear nerve due to occlusion of the labyrinthine artery, a common branch of the AICA.
Clinical findings include ipsilateral ataxia, loss of pain and temperature sensation of the face, Horner syndrome, deafness, and contralateral pain and temperature loss of the limbs.
ciliospinal (pupillary-skin) reflex refers to
pupillary dilation in response to painful stimulation
Three embryonic communications between the vertebrobasilar and carotid systems are the trigeminal, otic and hypoglossal arteries.
Persistence of the trigeminal artery is the most common.
motor and parasympathetic portions of CN VII pass through the _______ ganglion without synapsing
geniculate
superior salivatory nucleus gives rise to
preganglionic autonomic fibers.
sphenopalatine ganglion contains the cell bodies of the
postganglionic fibers for lacrimation.
Sensory fibers originating from the external auditory canal and tympanic membrane as well as fibers conveying taste have cell bodies that reside in the
geniculate ganglion.
bilateral upper extremity weakness, affecting distal muscles more than proximal ones, with decreased pinprick sensation and retained fine touch, (i.e. a dissociated sensory level in a “cape-like” distribution) is most suggestive of a
central cord syndrome.
central cord lesion affecting the anterior commissure will affect the crossing spinothalamic tracts,
resulting in sensory deficits only at the level of the lesion. It will not cause more caudal sensory deficits and will spare vibration and light touch, since the dorsal columns are spared.
Venous blood of the torcula exit the skull via the
transverse sinus, then the sigmoid sinus, and then the jugular vein
grip a card or paper between the thumb and index finger indicates weakness of
thumb adduction and index finger abduction. Both of these muscles are innervated by the ulnar nerve. This is often called Froment sign or Froment prehensile thumb sign.
accommodating the Froment sign
by flexing the distal thumb and index finger making an OK sign. These muscles are innervated by the anterior interosseous nerve.
median nerve has motor branches to
lumbricals 1 and 2, the abductor pollicis brevis, the opponens pollicis brevis, and the flexor pollicis brevis, distal to the carpal tunnel.
third order neurons of the oculosympathetic pathway arise from the superior cervical ganglion on the common carotid artery.
A dissection of the internal carotid artery may result in an ipsilateral Horner syndrome with ptosis, and a miotic pupil that poorly dilates. The fibers destined for the facial sweat glands are carried on the external carotid artery and therefore would be spared.
third cranial nerve emerges from the midbrain at the level of the superior colliculus in the
interpeduncular fossa
structure is the substantia nigra, which projects to and receives fibers predominantly from the caudate and putamen.
Degeneration of this structure is seen in idiopathic Parkinson’s disease.
anterior commissure of the spinal cord, which is where the
fibers of the anterolateral system, carrying pain and temperature, decussate.
lateral geniculate nucleus, which receives
visual input from the optic tract.
Neural crest derivatives include cells of the dorsal root ganglia (involved in transmission of pain) and sympathetic ganglia.
These derivatives require nerve growth factor (NGF) for survival. Other neural crest derivatives are Schwann cells and melanocytes.
arcuate fasciculus is a connection between Wernicke’s area in the superior temporal gyrus and Broca’s area in the inferior frontal gyrus.
The inferior frontal gyrus can be subdivided into three parts: pars opercularis, pars triangularis, and pars orbitalis with the first two being the anatomical substrate for Broca’s area.
global brain ischemia, damage may be seen most conspicuously in parts of the cerebral cortex, hippocampus and the cerebellar Purkinje cells.
In the neocortex, layer 3 is the most vulnerable to global ischemic injury, with layers 2 and 4 the most resistant. The reason for this selective vulnerability is unknown.
Innervation of the dura within the cranial vault is provided by
ophthalmic branch of the trigeminal nerve.
The greater occipital nerve innervates the scalp on the
back of the head.
greater petrosal nerve innervates the
lacrimal gland
maxillary and mandibular divisions of the trigeminal nerve innervate the
skin of the face below the eyes.
Sympathetic fibers descending in the lateral dorsal medulla, lie in close approximation to the
inferior cerebellar peduncle, nucleus ambiguous, fibers from the dorsal motor nucleus of X, vestibular nuclei, spinothalamic tract, and spinal trigeminal nucleus. These structures are supplied by the posterior inferior cerebellar artery and are involved in a Wallenberg syndrome.
infundibulum carries compounds from the hypothalamus to the
neurohypophysis and adenohypophysis modulating the activities of these structures
hypothalamic derived compound that tonically inhibits pituitary gland synthesis and release of prolactin is
dopamine (also known as prolactin inhibitory factor)
Interruption of the infundibulum leads to loss of tonic inhibition of prolactin secretion by
dopamine and elevation of prolactin
dopamine receptor antagonists will elevate prolactin and
dopamine receptor agonists can suppress
prolactin secretion and have been used in the medical management of prolactin secretion pituitary adenomas.
Fetal posterior cerebral artery is a common vascular anomaly, where the distal PCA is supplied by the
internal carotid artery, with an absent P1 segment. PCA territory is supplied by the anterior circulation; thus, internal carotid artery lesions can be responsible for PCA strokes.
Decerebrate posturing is due to dysfunction of the red nucleus and the rubrospinal tract with preserved function of the lateral vestibular nucleus and the lateral vestibular spinal tracts
rubrospinal tract facilitates motor neurons in the cervical cord subserving flexor muscles of the upper extremities. The lateral vestibulospinal tract facilitates motor neurons in the lumbosacral cord subserving extensor muscles of the lower extremities.
Entrapment of the suprascapular nerve may cause
shoulder pain, weakness of shoulder abduction, and sparing of sensation about the shoulder.
axillary nerve supplies sensation to the skin
overlying the lateral deltoid.
pulvinar receives fibers from the superior colliculus and projects to
areas 17, 18 and 19.
inferior and lateral pulvinar have
reciprocal connections with the occipital cortex.
medial geniculate receives input from the ______ while the ventral anterior nucleus receives input from the ______ - particularly the non-motor information stream.
inferior colliculus, globus pallidus pars interna
The ventral posteromedial and posterolateral nuclei receive _________
somatosensory input.
lateral dorsal nucleus has connections similar to those of the anterior nucleus to which it is adjacent though it may also have _________
posterior parietal connections as well.
Wisconsin Card Sort Test (WCST), which challenges a patient to change cognitive sets without warning, is particularly sensitive to ______ damage.
frontal
Face recognition and visual perception abnormalities such as hemi-inattention syndromes are most often associated with damage to the _______ rather than the frontal lobes.
parietal, temporal, or occipital lobes,
Patients who chronically inhale toluene vapors develop dementia (clinically consistent with ____________ and in some cases cranial nerve palsies.
subcortical dementia), cerebellar ataxia and long tract findings, not uncommon for these patients to also manifest a paranoid psychosis.
MRI findings of toluene toxicity
diffuse leukoencephalopathy, cerebral atrophy, and T2 hypointense lesions of the thalamus and/or the basal ganglia
posterior cortical atrophy present with progressive deficits that affect the dorsal and ventral streams of vision.
They tend to have preserved insight and lack the characteristic memory deficits which are pathognomonic for Alzheimer disease
angular gyrus syndrome results from an infarct or mass lesion affecting the angular gyrus on the dominant side.
The syndrome consists of difficulty with naming, reading, writing, memory and contains the elements of a Gerstmann syndrome
Semantic dementia is a subtype of
frontotemporal lobar degeneration, Patients early on have fluent spontaneous speech but have simplified content and anomic substitutions with general words. They also fail to correctly read or spell irregular words.
corticobasal degeneration and primary progressive aphasia usually present with a ________
nonfluent aphasia.
Posterior cortical atrophy usually presents with _________
visuospatial and visuoperceptual abnormalities.
Alzheimer dementia’s language issues are usually word-finding difficulties as well as ________
memory and language retrieval abnormalities.
multiple system atrophy (MSA)
This condition can manifest with parkinsonism, cerebellar dysfunction, or pyramidal tract signs. Patients with MSA frequently have alpha-synuclein inclusions distributed throughout the cortex.
Contusion of the orbitofrontal cortex is associated with ________
social disinhibition.
Apathy, depression and loss of task set is more commonly seen in ____________
dorsolateral prefrontal lesions.
Akinetic mutism is more commonly associated with ________
medial frontal lesions
Anton syndrome, (the denial of blindness), despite objective evidence of visual loss, is typically associated with _____________
bilateral posterior cerebral artery territory infarction producing cortical blindness plus memory impairment.
Haloperidol, perphenazine, and trifluoperazine are antipsychotics with a mechanism of action of antagonism of dopamine receptors in the _________. They block postsynaptic mesolimbic dopaminergic D1 and D2 receptors in the brain.
mesolimbic and mesofrontal systems.
JC papovavirus that affects immunocompromised patients. It has a predilection for the __________
white matter in the bilateral occipito-parietal regions.
Right-left confusion occurs with dominant parietal lobe lesions, and can be associated with ____________
finger agnosia, agraphia and acalculia, as well as alexia (Gerstmann syndrome).
Neglect or denial of the contralateral (usually left) half of the body and space generally results from damage to the ___________
non-dominant parietal lobe.
Dressing apraxia appears to be a related phenomenon and has been seen in patients with lesions in the ________
dominant parietal region
Impaired ability to perceive emotions (alexithymia) is a personality dysfunction seen in some psychiatric conditions including ____________
affective disorders and autism, with unclear specific localization.
Prosopagnosia results from ___________
occipital or occipitotemporal lesions, generally bilateral.
rapid switch from overvaluing her doctor to devaluing him
dichotomous thinking
Phonemic errors are more typical of _______ loosening of associations may mimic the rambling jargon of Wernicke aphasia, but can be distinguished by intact comprehension.
Broca’s aphasia,
NSE, like 14-3-3, is elevated in any condition in which there is _______ including CJD and hypoxic injury.
rapid neuronal death
Tau is increased in _____ disease
Alzheimer
Spelling “WORLD” backward or alternatively doing serial 7s is the assessment for _______
attention and concentration
Three variants of PPA have been described;
semantic dementia, nonfluent/agrammatic aphasia and logopenic aphasia.
Patients with ___________ have significant atrophy in the left posterior parasylvian or parietal region,
logopenic aphasia
patients with ________ have atrophy in the left anterior temporal regions
semantic dementia
patients with _________ have atrophy involving the left frontoinsular region.
nonfluent/agrammatic aphasia
Atrophy of the ______ is associated with Alzheimer’s disease
left medial temporal region
Atrophy in the orbitofrontal region is associated with _________
behavior variant frontotemporal dementia.
Balint syndrome, identified by Rezs (Rudolf) Bàlint in 1909, is characterized by
optic ataxia (the inability to accurately reach for objects), optic apraxia (the inability to voluntarily guide eye movements/ change to a new location of visual fixation), and simultanagnosia (the inability to perceive more than one object at a time, even when in the same place).
Balint syndrome has been found in patients with bilateral damage to the
posterior parietal cortex (and rarely, the frontal lobe; perhaps due to parietal frontal eye-field disconnection).
Serotonin syndrome is characterized by
mental status changes, autonomic instability and neuromuscular hyperactivity.
Neuroleptic malignant syndrome is caused by
dopamine receptor blockade usually secondary to an adverse reaction to antipsychotic medications. It is characterized by muscle rigidity followed by hyperthermia and altered mental status.
Malignant hyperthermia is a rare condition linked to mutations in the
ryanodine receptor gene and exposure to anesthetic agents such as succinylcholine. It is characterized by muscle rigidity and hypermetabolic state.
Toxic shock syndrome is a life-threatening illness generally caused by infection with
Staphylococcus aureus. It is characterized by rash, hypotension, high fever and multiorgan failure.
toddler with classic Rett syndrome appears normal to her parents for most of the first year of life
except for possible mild motor delays.
Natural hx of Rett syndrome
Purposeful hand use is replaced by stereotypic hand movements. The lost developmental skills are never recovered; and she moves through life at a level of profound intellectual disability often accompanied by seizures.
______ gene mutation is the cause of Rett syndrome
MeCP2
_______ deficiency is the cause of Canavan disease which typically appears in early infancy and progresses rapidly from that stage with abnormal muscle tone, poor head control, and megalocephaly.
Aspartoacylase
_______ injury is the cause of cerebral palsy, a permanent movement disorder with or without mental dysfunction
Neonatal hypoxic ischemic
_______ gene mutation is the cause of Lafora body disease with symptoms of seizures, drop attacks, myoclonus, and ataxia manifesting in children from 10 to 17 years old.
EpM2A
Copper accumulation is the cause of _____ disease, with symptoms typically beginning between 5 and 35 years old and manifesting with behavioral changes, tremors, hallucinations, and liver dysfunction from copper overload.
Wilson’s
_______ identified by antithyroid antibodies, can cause cognitive dysfunction including confusion, memory loss, aphasia and word finding problems and seizures.
Hashimoto’s Thyroiditis, Hints include the high dose of thyroid medication with the thyroid-stimulating hormone still elevated. Evidence of nonspecific inflammatory markers such as polyclonal gammopathy may be present.
Vitamin B12 deficiency may be associated with _____ but does not typically cause seizures.
anemia
Vasculitis and seizures due to lupus are often accompanied by ________
new infarcts.
Patients with _____ lack the usual limb paralysis that normally accompanies REM sleep.
REM behavior disorder
Non-REM sleep disorders such as _______ do not usually involve violent behaviors, although they can in rare cases
somnambulism
______ lobe seizures rarely lead to complex violent behavior.
Frontal
Classic findings of prion disorders include
hyperekplexia (exaggerated startle), insomnia, encephalopathy, and ataxia.
asymmetric rigid parkinsonism manifested by focal dystonia and apraxia are classic early features seen in most patients with _______. The presence of an alien limb while almost diagnostic is not universally present.
corticobasal syndrome
locked-in syndrome is characterized by
being mute, quadriplegic, with preserved consciousness demonstrated by blinking or voluntary vertical eye movements with inability to voluntarily move eyes horizontally
The locked-in syndrome is not coma;
it results from lesions below the mid pons that preserves the brainstem reticular activating system for arousal and the brain for consciousness. Locked-in syndrome usually has preserved pupil reactivity and hearing as well.
right parietal lobe tumor could interfere with the optic radiations and cause a
left inferior quadrantanopsia (spares Meyer loop). Tumor could cause impaired graphesthesia in the left hand only, not both
Gerstmann syndrome may occur if the
left (dominant) parietal lobe was affected.
Receptive aprosody may occur in
right temporoparietal lesions
Neglect is a common finding in
right parietal lesions.
HIV infection can result in minor cognitive and motor disorder, HIV-associated mild neurocognitive disorder, and HIV-associated dementia.
The earliest symptoms revolve around mental slowing and processing speed
Dextromethorphan (combined with quinidine which serves to increase the bioavailability of dextromethorphan) is a dual action glutamate inhibitor, via sigma-1 agonist activity and also via NMDA receptor antagonism
these actions are believed to help regulate excitatory neurotransmission to diminish the unpredictable emotional episodes of pseudobulbar affect
Sigma-1 receptors are expressed in specific regions of the brain such as layers of the cortex, hippocampus, hypothalamic nuclei, substantia nigra and Purkinje cells in the cerebellum.
Although the exact molecular action of sigma-1 receptors is still unclear, a number of studies have demonstrated that they play a role as a modulator of ion channels (K+ channels; N-methyl-D-aspartate receptors [NMDA]; inositol 1,3,5 trisphosphate receptors).
Sigma-1 agonists, while having no effects by themselves, cause the amplification of signal transductions incurred upon the stimulation of the glutamatergic, dopaminergic, IP3-related metabotropic, or nerve growth factor-related systems.
hypothesized that sigma-1 receptors, at least in part, are intracellular amplifiers creating a super sensitized state for signal transduction in the biological system.
dorsomedial nucleus (commonly seen in Korsakoff syndrome) result in ____________
encoding deficits and therefore memory loss.
Lesions of the paramedian region of the thalamus generally result in __________
apathy, disinterest and lack of drive.
Lesions of the ventral posterior region generally result in
sensory loss.
Lesions of the intralaminar and reticular nuclei affect
normal alertness
clinical criteria for frontotemporal dementia (FTD) include
gradual onset with progressive decline, changes in personal hygiene, loss of social decorum, lack of insight, emotional blunting, and loss of empathy
FTD has been linked to motor neuron disease, as well as _______, both in the patients with FTD as well as in family members.
parkinsonism
TAR DNA-binding protein 43 (TDP-43) is a major protein component of the ubiquitin-immunoreactive inclusions characteristic of
sporadic and familial frontotemporal lobar degeneration with ubiquitin-positive, tau-negative inclusions (FTLD-U), with and without motor neuron disease, as well as in sporadic amyotrophic lateral sclerosis (ALS)
These conditions with TDP-43 do not have
tau, beta-amyloid, or alpha-synuclein inclusions.
Alpha-synuclein inclusions are seen in dementia with
Lewy bodies and Parkinson disease.
Tau inclusions are seen in some other types of ________.
frontotemporal dementias and Alzheimer disease. Beta-amyloid inclusions are classically seen in Alzheimer disease.
Pick bodies are aggregations of tau protein in neurons associated with Pick disease, a subtype of _______
frontotemporal lobar degeneration.
Midodrine is a prodrug that is metabolized in the liver to ______, a potent alpha-1 adrenergic agonist that produces arterial and venous vasoconstriction.
desglymidodrine. Unlike other sympathomimetics, midodrine has a predictable absorption and plasma half-life. It is currently the drug of second choice after fludrocortisone for management of neurogenic orthostatic hypotension
midodrine dose is 10-40 mg/day. It should not be administered in the evening given the risk of supine hypertension.
Scalp pruritus is a common side effect.
Epilepsy related visual hallucinations are characteristically ________
very brief and simple. They tend to occur in a hemifield and are associated with a description of motion.
Migraine aura may be confounded with occipital seizures but is typically much
longer lasting and classically consist of geometric patterns such as black and white zigzag lines which are often scintillating in character.
Acute ischemic stroke in the distribution of the _________ is the leading cause of acute audiovestibular loss.
anterior inferior cerebellar artery (AICA)
Isolated hearing loss without other neurologic symptoms is associated with a ___________
labyrinthine artery infarction
In the absence of an EEG, ________
pupillary dilatation and hypertension can be signs of persistent electrographic seizure activity.
Inclusion body myositis is an inflammatory condition in older individuals (male predominant) which is slowly progressive.
Clinical features of early weakness and atrophy of select muscles is found: quadriceps, flexors of the forearms and ankle dorsiflexors.
polymyositis is generally more
fulminant, painful and symmetric;
central core disease is
congenital with fairly mild progression over life
both types of myotonic dystrophy are autosomal dominant, typically present
earlier in life and have many systemic manifestations
recurrent, self-limiting, aseptic meningitis – which has also been called Mollaret meningitis.
This syndrome is caused by the herpes simplex virus 2 and may benefit from treatment with acyclovir.
Huntington disease is an autosomal dominant movement disorder characterized by
chorea, dementia and behavioral disturbances.
Cervical spinal stenosis could also produce
painless four-limb weakness with upper motor neuron signs in the legs
Fasciculations and wasting in the lower extremities are not symptoms of cervical stenosis as they imply a disorder of the lower motor neuron at the ________-
lumbosacral level
In addition to symptoms of headache, transient visual obscurations, diplopia, and visual loss, many patients with IIH also experience _________
pulsatile tinnitus.
patient’s signs and symptoms of sensory loss to pinprick with preservation of vibratory sense and reflexes, is most consistent with a ______
small fiber neuropathy
His symptoms are compatible with leprosy, which occurs due to Mycobacterium leprae, a neurotropic bacterium.
This diagnosis is supported by the distribution of this patient’s sensory loss, which includes his ears and nose, and the fact that he has emigrated from a country endemic for leprosy.
Propofol has been reported to cause ______
dystonic reactions
large _______ with neurologic deterioration over the last couple of hours. While medical therapy can be attempted as a temporizing measure, this patient will likely need a suboccipital craniectomy given the size of the stroke and the rapid deterioration over hours.
left cerebellar stroke
trigeminal autonomic cephalgias are a group of primary headache disorders characterized by .
short-lasting episodes of severe unilateral headaches that are associated with ipsilateral cranial autonomic symptoms
Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing
(SUNCT) syndrome,
The attacks of SUNCT syndrome
resemble those of cluster headaches but are primarily differentiated by the
much briefer attack duration and greater frequency in SUNCT than cluster headache.
SUNCT can also resemble V1 trigeminal neuralgia but the latter should not have the
prominent autonomic features of SUNCT.
Triptans are contraindicated in the presence of known coronary artery disease due to the risk of
precipitating vasospasm and coronary ischemia.
isolated trochlear nerve palsy
microvascular ischemia in the setting of high blood pressure and diabetes is the most common cause of this condition
Verapamil, a calcium channel blocker, is currently the preferred agent for prophylaxis of ______
cluster headaches during a cluster.
Verapamil can be titrated off once the patient has been headache free for more than 2 weeks as there is __________
no known prophylactic benefit between clusters.
fingolimod, is a sphingosine 1-phosphate receptor inhibitor.
It’s putative mechanism of action in MS is sequestration of lymphocytes in lymph nodes.
Pseudotumor cerebri is characterized by
headaches, visual obscurations and papilledema
Several medications including _________ are associated with the development of pseudotumor.
isotretinoin and other vitamin A-containing compounds
In patients within the 6-hour window with a head CT demonstrating an ASPECTS > 6, no additional imaging is needed beyond a
CT angiogram demonstrating a large vessel occlusion
“HINTS to diagnose stroke in the acute vestibular syndrome” include the presence of skew eye deviation (vertical ocular misalignment), nystagmus which changes direction on eccentric gaze, and the absence of vestibulo-ocular reflex tested by the bedside horizontal impulse test. A brainstem lesion is highly likely when the acute vestibular syndrome is associated with any of these findings.
Skew eye deviation is the most sensitive, being even more sensitive than brain MRI for the diagnosis of acute brainstem stroke in the first 48 hours of symptom onset.
diagnosis of probable multiple system atrophy can be made in a patient with symptoms of __________
autonomic failure (typically beginning with bladder and erectile dysfunction, with prominent orthostasis on examination) and no response to levodopa.
Fingolimod has been associated with ______ in approximately 1% of treated patients.
macular edema
Weakness of ankle dorsiflexion could localize to the
deep peroneal (fibular) nerve, common peroneal (fibular nerve), sciatic nerve, lumbosacral plexus, or L5 nerve root.
The involvement of ankle eversion eliminates the
deep peroneal (fibular) nerve ankle eversion is innervated by the superficial peroneal (fibular) nerve
The involvement of ankle inversion eliminates the common peroneal (fibular) nerve since ankle inversion is innervated by the
tibial nerve
The sparing of ankle plantarflexion argues against either the
Lumbosacral plexus or the sciatic nerve. In this context, L5 is the most likely localization.
Most cases of trigeminal neuralgia are thought to be due to compression of the trigeminal nerve by a
vascular loop. Imaging is indicated to exclude other, though less common, structural causes such as a meningioma, cerebellopontine angle neoplasm, and aneurysm.
(known as the recurrent artery of Heubner) is a branch of the anterior cerebral artery that supplies part of the
caudate head.
The caudate head is also supplied by branches of the _______
middle cerebral artery.
pericallosal arteries are branches of the anterior cerebral artery that supply ________
medial aspects of both hemispheres
anterior choroidal artery supplies the
posterior limb of the internal capsule, the medial globus pallidus, and the lateral geniculate body.
posterior choroidal artery supplies the
lateral geniculate body, pulvinar, posterior thalamus, hippocampus, and parahippocampal gyrus
artery of Percheron is a variant that supplies
both thalami.
According to the SAMMPRIS Study, best medical management with
high dose statin, blood pressure control, and dual antiplatelet therapy with aspirin and clopidogrel for 3 months is the optimal treatment for patients with stroke from severe intracranial atherosclerosis and was shown to be more efficacious than mechanical interventions.
WASID study showed that antiplatelets had overall better outcomes than
anticoagulation for patients with severe intracranial atherosclerosis.
Cerebral vasospasm is a serious complication of subarachnoid hemorrhage typically occurring between the _______. It often presents with focal neurologic deficits and drowsiness.
4th and 14th day after hemorrhage
Diabetic lumbosacral radiculoplexus neuropathy presents with ______, followed by muscle weakness and atrophy
acute and severe proximal lower limb pain. It is the most commonly observed in patients with well-controlled type 2 diabetes mellitus.
patient developed hypertension, a seizure, and cortical blindness that is consistent with a reversible posterior leukoencephalopathy while on
bevacizumab.
_______ is also associated with an increased incidence of stroke, intracranial hemorrhage, and optic neuropathy.
Bevacizumab
history is consistent with Mal de debarquement syndrome, described by patients usually as a feeling of
motion, rocking or swaying when there is no physical motion. Notable for typically lacking nausea, vomiting, vertigo or other common vestibular symptoms as well as an absence of hearing symptoms.
Patients usually feel some relief by being in motion themselves, either by driving or going back out on the ocean, and they feel most symptomatic when they are ________
sitting still.
patient’s symptoms and EEG findings are most consistent with ________
juvenile myoclonic epilepsy (JME).
JME is a generalized epilepsy that typically presents during
adolescence or early adulthood.
patients with sickle cell disease and stroke, blood transfusions to reduce the hemoglobin S level to under ___ is recommended.
30%
post-transplant lymphoproliferative disease (PTLD) resulting from _________. EBV causes monoclonal transformation of B-lymphocytes and in turn can result in primary CNS lymphoma.
chronic immunosuppression and activation of Epstein-Barr virus (EBV) infection.
lateral femoral cutaneous nerve innervates the _______
mid portion of the lateral thigh
In a lateral femoral cutaneous neuropathy the nerve conduction studies would demonstrate a ______. The EMG should be normal.
absence or reduced lateral femoral sensory action potential.
early delayed radiation injury is Lhermitte sign and is characterized by
electric shock-like sensation or paresthesia on the spine and limbs upon flexion of the neck. This develops 3 to 4 months after treatment and spontaneously resolves.
Superior canal dehiscence syndrome, first described a few decades ago, presents in several different ways, with either acoustic or vestibular symptoms predominating.
It is due to a Valsalva-induced communication between a dehisced superior semicircular canal bone and the intracranial space.
patient has signs and symptoms of an acute transverse myelitis with a longitudinally extensive lesion by MR imaging.
When superimposed on a history of a severe optic neuritis this presentation is most compatible with neuromyelitis optica spectrum disorder (NMO). The NMO antibody (NMO-IgG), an antibody to the aquaporin-4 water channel, is a specific, though not 100% sensitive, marker for neuromyelitis optica.
nonarteritic anterior ischemic optic neuropathy (NAION) resulting in
optic nerve head ischemia. This is usually due to vascular occlusive disease of the posterior ciliary arteries which supply the optic nerve. primary risk factors are hypertension and diabetes mellitus. Most patients awaken with painless monocular visual loss presumably because of nocturnal hypotension.
PML
MRI reveals non-enhancing FLAIR abnormalities that involve the white matter more than the gray matter. Diagnosis is made by CSF demonstration of JC virus.
Acute bacterial meningitis is characterized by
headache, fever, nuchal rigidity, mental status changes and photophobia. Emergent treatment in a patient with a high suspicion of the diagnosis is dexamethasone given simultaneous with or followed by empirical antibiotics.
Bacterial meningitis tx
3rd generation cephalosporin and vancomycin,
Down syndrome can be associated with
atlantoaxial instability. Special precautions must be taken prior to any intubation in order to prevent neurologic damage.
idiopathic brachial neuritis
disorder is more common in young adults and sometimes follows physical exertion or other physical stress, including upper respiratory tract infection, vaccination, surgery, and childbirth
brachial plexitis presents with
severe pain followed by weakness and sensory loss in the upper extremity. Weakness may occur within 24 hours, but its onset is more commonly delayed two weeks or longer.
location of the hemorrhage in the temporal lobe is a common location of hemorrhage from a transverse sinus thrombosis.
In a venous sinus thrombosis, the hemorrhage is caused by a backup of blood into the parenchyma because of abnormal blood flow into the venous system and out of the brain.
Adie’s pupil is typically initially large although becomes
smaller over time. minimal reaction to light but normal constriction to near, i.e. light-near dissociation.
Unlike normal pupils, which will show no response to instillation of dilute pilocarpine,
Adie pupils will constrict to this agent due to denervation super sensitivity from ciliary ganglion dysfunction
Unlike Adie pupils,
Argyll-Robertson pupils due to neurosyphilis are typically bilaterally small.
Adie pupils are often associated with impaired muscle stretch reflexes;
this combination of findings is referred to as the Holmes-Adie syndrome
Apraclonidine is used to detect a
Horner pupil which should dilate in response to this agent.
Eculizumab is a first-in-class humanized monoclonal antibody developed to target the
cleavage of C5. Tx of paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome and most recently in myasthenia gravis.
Eculizumab can impair
neutrophil and monocyte functions and predispose to encapsulated bacterial infections.
Whipple disease, a rare multisystem disorder secondary to infection by
Tropheryma whipplei, a Gram-positive, non-acid-fast, periodic acid-Schiff (PAS) positive Bacillus
Celiac disease presents with gastrointestinal complaints either in childhood or adulthood, and the principle neurological manifestation is
ataxia
Progressive supranuclear palsy and Multiple system atrophy develop in a more
subacute to chronic manner with other prominent features
In patients with acute onset of epidural spinal cord compression, patients who underwent surgery within 24 hours had significant improvement in their
ability to walk and the length of time that they were able to continue to walk.
Metronidazole is associated with a toxic sensorimotor polyneuropathy affecting both
large and small fibers.
Toxicity of metronidazole is dependent on
cumulative dose (usually greater than 30 gm) and recovery is often delayed for 6 to 12 months.
patients with acute exacerbations of MS who fail to improve with IV methylprednisolone,
plasma exchange is a reasonable next step.
Progressive supranuclear palsy typically presents in the
seventh decade, with early postural instability, vertical supranuclear gaze palsy, and levodopa-unresponsive parkinsonism. This patient’s signs and symptoms of early falls, symmetric Parkinsonism, and
hyperextended neck are most compatible with progressive supranuclear palsy
Dementia with Lewy body presents with
dementia and visual hallucinations.
Spinocerebellar atrophy has a ____ as a common presenting sign
ataxia
Multiple system atrophy presents with prominent
autonomic symptoms.
______ allele is predictive of carbamazepine induced severe rash including Steven-Johnson syndrome and toxic epidermal necrolysis and therefore should be tested on patients of Asian descent.
HLA-B 1502
utero exposure to _____ is associated with autism spectrum disorder
Valproic acid
hereditary neuropathy with liability to pressure palsies (HNPP)
findings of demyelination on the nerve conductions is consistent with HNPP. Patient should have genetic test for HNPP which is due to a duplication in PMP 22. Think PP is a duplication
idiopathic glossopharyngeal neuralgia. Secondary causes, including
skull-based tumors, have been adequately excluded by MRI. Syncope associated with this syndrome results from activation of the carotid sinus branch of the glossopharyngeal nerve, resulting in bradycardia and hypotension due to peripheral arterial vasodilatation.
cataplexy is an
emotionally-induced loss of strength and postural tone.
CRPS 1 is most closely associated with
trauma to a limb, include acute burning pain, hyperalgesia and allodynia in the absence of any demonstrable nerve injury.
Bone scintigraphy has been shown to be useful in the
acute phase of CRPS 1 and may show homogenous unilateral hyper perfusion in the two early phases of the test with increased periarticular radiotracer uptake in the delayed (3 hour) phase.
Ma2 antibodies are predominantly found in young males with ______. Patients with Ma2 antibodies most often have limbic system encephalitis and eye movement abnormalities, especially paresis of _____, but can also have cerebellar degeneration. These patients should be evaluated for ________.
germ cell tumors, vertical gaze, testicular cancer.
Of the causes of congenital infections listed (CMV, Rubella, HIV, Syphilis, and toxoplasmosis), ______ is the most likely to manifest after delivery with liver abnormalities and obstructive hydrocephalus
toxoplasmosis. Look for “sundown” eyes
Neonatal encephalopathy from hypoxic-ischemia as in this case can injure the _________
basal ganglia / thalamus, cerebral cortex, watershed cortex and white matter, or periventricular / central cerebral white matter.
patient described has a history consistent with _____ encephalopathy (nonketotic hyperglycinemia), given frequent apnea, myoclonus, and burst suppression pattern on EEG
glycine. frequent “hiccups” of the fetus in utero. diagnosis is made by CSF amino acids, typically compared to serum amino acids, where an elevated glycine level is seen, with an increased ratio of CSF:serum glycine
Urine sulfites are increased in ________
molybdenum cofactor and sulfite oxidase deficiency.
Very long chain fatty acids can be elevated in _________
Zellweger syndrome and other peroxisomal disorders
Urine organic acids can determine some causes of neonatal encephalopathy and seizures, such as ________
methylmalonic aciduria and maple syrup urine disease.
Involvement of muscle is a characteristic feature of mitochondriopathies such as ______, as is neuropathy
cytochrome oxidase type 1 deficiency
__________ would present with difficult to control epilepsy
Glucose transporter deficiency type 1
_______ presents as a progressive encephalopathy, episodes of stroke, and hepatomegaly.
Methylmalonic acidemia
________ is one of the benign focal epilepsies of childhood; with a frequency about half of childhood epilepsy with centrotemporal spikes (CECTS).
Benign occipital epilepsy (Panayiotopoulos syndrome)
characteristic presentation of spinal epidural abscess is a _________. This is a neurosurgical emergency
transverse myelopathy and a flexed posture resisting extension
Features of ADEM include a single polyfocal CNS event with a presumed demyelinating cause.
Lesions tend to be bilateral, and affect the deep grey structures and cortex.
_______ may also affect children of this age and be post-inf
Acute cerebellar ataxia
_______ is a mitochondrial disorder, and while acute worsening can occur with infection, one would not expect typical development at this age of 4 years.
Leigh disease
acute flaccid myelitis (AFM), characterized by acute weakness in >1 limb and either a
spinal cord lesion on MRl restricted to the gray matter spanning >1 spinal segments for a confirmed case or a CSF pleocytosis of >5 white blood cells/mm3 for a probable case.
dermatomyositis
A muscle biopsy would show perifascicular atrophy with sparing of the central fascicle, along with perivascular inflammation.
_______ may produce abnormalities of tone and movement that result in a Parkinsonian syndrome
GTP cyclohydrolase deficiency
Aicardi syndrome generally does not occur in _____
boys
______ has a static or slowly progressive course with rod-like inclusions on trichrome studies
Nemaline myopathy. Creatine kinase is normal or mildly elevated; EMG may be normal. The most common cause is a mutation in the alpha-actin gene.
Fukuyama muscular dystrophy would not have the noted inclusions, nor would Mersin-deficient myopathy
Mitochondrial myopathy would show ragged red fibers.
Benign paroxysmal torticollis is classified as a migraine equivalent by the International Headache Society.
Some children go on to develop basilar-type migraines.
Sandifer syndrome is
posturing from esophageal discomfort and usually involves the trunk.
Spasmus nutans has
ocular oscillations along with head tilt, and dopa-responsive dystonia usually begins after 5 years of age, typically in the foot.
Narcolepsy consists of a diagnostic tetrad that includes
excessive daytime sleepiness, cataplexy, hypnagogic or hypnopompic hallucinations, and sleep paralysis
Diagnosis of narcolepsy is usually made when a positive
multiple sleep latency test (MSLT) is found in individuals who experience both excessive daytime weakness and cataplexy.
By definition regressive autism occurs
prior to three years of age, while the peak age of language loss with Landau-Kleffner syndrome is 5-7 years of age
Although behavioral and cognitive dysfunction may be found in Landau-Kleffner,
these appear to be the result of language dysfunction, while they arise with equal primary significance in autistic regression. Prognosis for recovery is worse with earlier age of onset for both conditions
75% of children with Landau-Kleffner manifest seizures, whereas
convulsive seizures are far less common in children with autistic regression.
Childhood Epilepsy with Centrotemporal Spikes (CECTS) is characterized by onset between
5 and 7 years of age, nocturnal occurrence, and benign interictal neurologic examination, and a characteristic EEG with independent Centro-temporal spikes with a horizontal dipole.
Childhood absence remits in
about two-thirds of children, although a few develop generalized convulsive epilepsy in adolescence or adulthood
JME often requires prolonged or indefinite treatment, with only about
20% remitting.
Infants with prolonged febrile seizures followed by
multiple seizure types are often manifesting Dravet syndrome and respond poorly to treatment
Lennox-Gastaut syndrome rarely remits and is often
intractable.
Typical features of kernicterus are early hypotonia, followed by
opisthotic posturing and later athetoid/dystonic
Cerebral palsy with lack of
vertical gaze, sensorineural hearing loss, but preserved intelligence.
Infants with glutaric aciduria typically deteriorate markedly after a
minor illness causing a catabolic state.
Pelizaeus-Merzbacher syndrome is associated with
coarse nystagmus, lack of myelination diffusely on MRI
Lesions of kernicterus may be inapparent on CT or even on MRI, but there may be
cystic changes in globus pallidus with high signal on T2-weighted images
Juvenile Huntington disease more often presents with
bradykinesia and dystonia, not usually chorea.
MELAS and Kearns-Sayre syndrome may present with a variety of findings, but
symmetric chorea or athetosis would be unusual.
HIV encephalopathy, if untreated, typically causes loss of motor function,
usually with spasticity as the major component
PKAN is generally characterized by
progressive dystonia.
hypothalamic hamartoma
Typical presentation is gelastic epilepsy (seizures beginning with mirthless laughter).
Eleven percent of pediatric brain tumors are pilocytic astrocytomas, and 80% are cystic.
Medulloblastomas are rarely cystic
Dandy-Walker malformations usually present in the
first year of life.
Cysticercosis in the posterior fossa most often presents extra-axially, and the enhancement is usually
ring-like.
Labhart-Prader-Willi presents with
hypotonia, small size and usually poor feeding
SMA I patients have
absent reflexes
Patients with Sotos syndrome demonstrate macrocephaly, metachromatic leukodystrophy presents with
absent or very diminished reflexes and may have Babinski signs, and Zellweger syndrome presents with very significant hepatomegaly.
congenital myasthenic syndromes are not related to an immune process but are caused by
genetic defects affecting the neuromuscular junction. defects in acetylcholine synthesis and packaging (familial infantile myasthenia gravis), end-plate deficiency of acetylcholinesterase, acetylcholine receptor deficiency, and the slow channel syndrome.
standard of care for neonates born at 36 weeks gestational age or older with neonatal encephalopathy from suspected or confirmed hypoxia-ischemia is
72 hours of therapeutic hypothermia at 33.5C
Pain may result in excessive vagal tone and bradycardia or asystole with
ensuing pallid breath-holding
glycogen storage disease, type V (GSD V), caused by an
enzymatic defect on myophosphorylase encoded by PYGM on 11q13.This metabolic myopathy is characterized by exercise intolerance, myalgias, and muscle cramps. Patients can have myoglobinuria and rhabdomyolysis after extreme activity. CK can remain elevated
The following would mandate neuroimaging in a child presenting with headaches:
auras lasting more than an hour, persistent neurologic findings, abnormal neurologic exam between headaches, predominantly occipital headaches, loss of vision at headache peak, decline in cognitive function, decline in growth velocity, or recent significant change in headache pattern.
Spasmus nutans usually begins in the first year of life. Children are neurologically normal, although some may have coexisting amblyopia or strabismus.
The triad of abnormal head position(s), head nodding, and nystagmus is characteristic, although not all components need be present simultaneously, and the nystagmus may sometimes be monocular
While corpus callosotomy can be used in intractable epilepsy, this is more effective for
drop attacks (akinetic seizures).
Cerebellar mutism is a frequent postoperative problem in children who have had _______
posterior fossa surgery, particularly tumor resections that split the vermis.As the child improves, marked dysarthria is noted, with initially very sparse speech.
Medulloblastomas are a type of ______ arising in the cerebellum, most often occurring in the fourth ventricle.
primitive neuroectodermal tumor
Medulloblastoma MRI
MR spectroscopy characteristically has high choline peak, taurine peak, and low to absent N-acetylaspartate.
Epidural lipomatosis
there is significant fat posterior to thecal sac and the fat suppression post-contrast image shows that the signal of the epidural mass suppresses
Dural arteriovenous fistula would show
vascular flow voids and not uniform thickening of the fat.
The mass lesion with isointense signal on T1- and bright T2-weighted signal posterior to the dens is most frequently due to pannus.
The inflammatory pannus involving the dens is often seen in association with rheumatoid arthritis.
Arteriovenous malformation has
T2-hypointense flow-voids and more avid enhancement.
Binswanger disease is characterized by
subcortical foci of patchy T2 hyperintensities in white matter
decreased metabolism in the association cortex of the
parietal and temporal lobes and in the retrosplenial region is characteristic of Alzheimer disease
Corticobasal degeneration shows
decreased metabolism in the association cortex of one hemisphere but not the other, with a marked hemispheric asymmetry not present in this case.
Diffuse Lewy body disease is associated with
occipital hypometabolism.
Frontotemporal lobar degeneration is associated with decreased ______ metabolism.
frontal
Thyroid associated ophthalmopathy (Grave ophthalmopathy) is an _____ inflammatory condition of the orbit associated with hyper- or hypothyroidism.
autoimmune
single, large infiltrative multicystic enhancing mass with vasogenic edema.
This appearance is most frequently seen with a glioblastoma
cerebellar tonsillar ectopia (approximately 1 cm below the foramen magnum) with an
associated cervical syrinx, findings consistent with Chiari 1 malformation
Basilar invagination refers to
narrowing of the foramen magnum due to upward migration of the top of the C2 vertebrae.
Chordomas are tumors of notochord remnants which most often occur in the
clivus and sacrococcygeal regions.
Hepatic encephalopathy, in addition to diffuse atrophy has a striking increase in the _____
signal intensity of the basal ganglia on T1 weighted images
Wernicke Korsakoff CT findings may present with hypodensity in ___________
periaqueductal gray matter, mammillary bodies, and medial thalamus.
They are dilated Virchow-Robin or
perivascular spaces, around perforating arterioles or venules.
Hemosiderin deposits would appear ____ on T2.
dark
Craniopharyngioma would have more ______ enhancement and cystic features.
heterogenous
Epidermoid and Rathke cleft cysts do not typically _______
enhance so briskly
large pituitary mass has hyperdensity on the CT as seen with an acute hemorrhage.
The mass shows increase T1- and T2-weighted signal typical of recent hemorrhage. The combination of these findings is consistent with a pituitary apoplexy.
diffusion-weighted views demonstrate multiple focal areas of acute infarction. These involve both the deep gray and white matter along with scattered cortical areas of infarction.
These regions of infarction are in a multifocal vascular distribution atypical for branch large vessel disease and similarly atypical for small vessel infarctions or a cardioembolic etiology, which tend to be cortical. An MRA scan of the head performed concomitant with the study illustrated demonstrated marked beading along numerous arterial structures typical of vasculitis.
CT demonstrates air in a serpiginous pattern in the sulci consistent with
venous air embolism.
RCVS could cause
convexal SAH (which would be hyperdense rather than hypodense)
_____ is the commonest vascular lesion of the spine, accounting for about 70% of spinal vascular lesions.
Spinal dural arteriovenous fistula
Transverse myelitis has a more rapid pace than
spinal dural arteriovenous fistula.
juxta ventricular lesion is characteristic of the
vesicular stage of neurocysticercosis: a spherical cystic lesion with eccentric calcification (scolex) with no surrounding edema
Necrosis of the globus pallidus is the most common brain injury occurring in
carbon monoxide poisoning and is usually bilateral and symmetric.
Methanol poisoning has different appearance with
diffuse subcortical white matter lucency and bilateral putaminal infarctions that are often hemorrhagic.
The findings of Wernicke encephalopathy are likely not visible on CT but would be seen on MR as
periaqueductal and dorsal midbrain, mammillary body, and bilateral thalamic T2 hyperintensity.
Hepatic encephalopathy is similarly better seen on MR with
T1 hyperintensity in globus pallidus and subthalamic regions.
Wilson disease does not demonstrate hypodensities in the globus pallidus such as in this case and may demonstrate
atrophic changes in the basal ganglia, cortical and cerebellar regions.
Bartonella infection (catscratch disease) is frequently associated with a
small focus of enhancement at the disc optic nerve.
Dandy-Walker malformation is characterized
by incomplete formation of the vermis. markedly elevated torcula, and associated enlargement of the posterior fossa.
Joubert’s syndrome has a distinct recognizable morphology characterized by
abnormal development of midbrain structures (resembling a ‘molar tooth’.)
Posterior fossa arachnoid cysts have
normal vermis.
Chiari 2 has a towering cerebellum and
small posterior fossa.
Medulloblastoma is characterized by intraparenchymal mass lesion typically in the
midline cerebellum.
CT and MRI studies demonstrate a
cystic defect within the left anterior frontal region
lipoma would have increased signal on the ______ and higher density than seen on the CT scan.
T1-weighted sequence
T2 hyperintensity in the dorsal midbrain and the symmetrical abnormal enhancement in the mammillary bodies, periaqueductal tissue and dorsal midbrain and the FLAIR hyperintensity in the medial thalami are highly indicative of
Wernicke’s encephalopathy in this clinical setting
This is cystic, with a markedly enhancing nidus or mural nodule
he vessels in an AVM however, are significantly larger as compared to the capillary size vessels seen here. This lesion is also known as a capillary hemangioblastoma. Hemangioblastoma is a component of Von Hippel Lindau syndrome, which is also associated with renal cell carcinoma.
mesial temporal and hippocampal edema, and this and the clinical history supports diagnosis of herpes simplex encephalitis.
This disease often leads to elevated RBC count in CSF due to hemorrhagic changes
Elevated spirochete IgM levels can be seen in CNS Lyme Disease, which causes
multifocal white matter lesions.
Toxoplasmosis causes focal cerebritis rather than
diffuse edema in the temporal lobes.
A chordoma is a tumor mass that arises in
the sacrum not behind it.
Spondylolisthesis is the
displacement of one vertebra relative to the one adjacent to it.
Chronic inflammatory polyneuropathy demonstrates
thickened Cauda equine nerve roots.
The STIR sequence suppresses ______, suggesting that this mass is composed of fat.
fat signal
CT study demonstrates profound cortical atrophy with ventriculomegaly on an ex vacuo basis along with calcifications along the ependymal margin. This is a frequent finding in a setting of
congenital cytomegalovirus infections.
Fahr’s disease is an idiopathic disorder with calcifications involving the
basal ganglia, the cerebellar, dentate nuclei, and at times, the cortical ribbon, which is not the pattern seen.
Colloid cyst is the best response because the culprit lesion for this patient’s acute hydrocephalus is the hyper dense lesion that has acutely obstructed outflow from both lateral ventricles, resulting in their
acute enlargement and ballooning of third ventricle that causes effacement of the interpeduncular and suprasellar cisterns.
A complex formation of flow voids are seen in the left posterior temporal lobe.
These are most characteristic of arteriovenous malformations.
CT perfusion images demonstrate increased mean transit time, reduced blood flow, and reduced blood volume suggesting a
completed infarct
In the case of ischemia without completion of an infarct,
blood flow and volume would be relatively spared.
Luxury perfusion is characterized by
decreased mean transit time, increased blood flow, and increased blood volume
Spinal epidural hematoma is the best response, with imaging findings of an extradural collection that is slightly
hyperintense on T1 and hyperintense on T2 with some heterogeneous hypointense signal admixed in the thoracic portion of the collection.
Neuromyelitis optica has a predilection for the
hypothalamus and area postrema.
Acute demyelinating encephalomyelitis is characterized by
larger, confluent lesions.
This morphology with failure of formation of separate right and left cerebral hemispheres indicates.
holoprosencephaly
Canavan’s is a leukodystrophy associated with
large, rather than small head size.
Anencephaly is characterized by
absence of the major portions of the hemispheres and diencephalon.
Periventricular leukomalacia is characterized by
abnormal loss of white matter in the peritrigonal region.
anterior choroidal artery is a branch of the internal carotid artery and supplies the
posterior limb of the internal capsule and the lateral thalamus
paramedian thalamic artery is a branch of the
posterior cerebral artery and supplies the medial thalamus.
ophthalmic artery is a branch of the
internal carotid artery and supplies the retina.
Central neurocytomas are located in the
ventricles near the foramen of Monro and characteristically have attachment to the septum pellucidum
Choroid plexus papillomas and meningiomas
enhance intensely
Colloid cyst does not typically
enhance
Lymphoma is not typically an intraventricular lesion, but instead infiltrates
subependymal tissue and surrounds the ventricles, if involvement is near the ventricles.
gadolinium enhancement of pachymeningeal structures, suggesting
hypotension, carcinomatosis or lymphoma. The smooth, diffuse enhancement, together with low-lying tonsils appreciated on the sagittal image, are most consistent with CSF hypotension.
images demonstrate diffusion restriction of the cortical ribbon and basal ganglia consistent with
hypoxic-ischemic injury.
ovoid area with decreased T2 along the anterior third ventricle, typical of a large flow void.
The structure is also well seen as an irregular ovoid vascular structure arising from the anterior communicating artery typical of a saccular aneurysm.
In porencephaly, the
cyst is not lined by cortex
hydranencephaly
there is little brain tissue around a central cyst.
Toxoplasmosis is caused by an
obligate intracellular parasite Toxoplasma gondii. The most common regions affected are the basal ganglia or thalami, followed by juxtacortical white matter.
CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is
characterized by a history of migraine headaches (30%-40% of individuals), mid-adult (30s-60s) onset of cerebrovascular disease progressing to dementia, and diffuse white matter lesions and subcortical infarcts on neuroimaging
The pathologic hallmark of CADASIL is
electron-dense granules in the media of arterioles that can often be identified by electron microscopic (EM) evaluation of skin biopsies.
More than 90% of individuals have mutations in NOTCH3,
the only gene known to be associated with CADASIL
differential diagnosis of CADASIL includes
multiple sclerosis (MS), sporadic small vessel disease including Binswanger disease, and primary angiitis of the nervous system
CADASIL should also be considered in any young person who has
migraine with aura in conjunction with multiple white matter lesions on MRI
Venous sinus thrombosis is diagnosed by the
hyperdensity in the confluence of sinuses on head CT and by extensive T1-hyperintensity in the sagittal sinus and straight sinus on T1-weighted unenhanced MRI.
Methanol intoxication causes
necrosis of the optic nerves and putamen
Neuronal loss in mammillary bodies is typical of Wernicke Korsakoff disease caused by
thiamine deficiency
Neuronal loss in superior cerebellar vermis relates to
mercury poisoning.
Target fibers, which are best seen with Masson trichrome or NADH stains, are characteristic of
denervation/ reinnervation.
PAS-positive granules are seen in
cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).
Familial amyloidosis usually affects
peripheral nerves
Patients with autosomal dominant cerebral cavernous malformation syndrome may have mutations of the
KRIT1 gene on chromosome 7q.
Hippocampal sclerosis of aging (HS-Aging) is the best diagnosis for this patient with a
late-onset amnestic syndrome, bilateral hippocampal atrophy and massive neuronal loss limited to hippocampus, and with TDP-43 neuronal inclusions in limbic structures including dentate gyrus.
Pick’s disease is a subtype of FTLD-tau and would have
extensive tau pathology with characteristic tau-immunoreactive Pick bodies, including in the dentate gyrus
necrotizing vasculitis with
fibrinoid necrosis of the vessel walls
Takayasu arteritis affects large blood vessels such as
aortic arch, not small intramuscular vessels
Inclusion body myositis is an inflammatory myopathy with
rimmed vacuoles, not a vasculitis.
Hemangioblastoma is a highly vascular tumor that most often arises in the
cerebellar hemisphere, but that may also arise within the spinal cord and rarely in supratentorial locations
Porencephaly is felt to be a milder form of hydranencephaly which is theorized to be
secondary to a vascular insult during gestation.
perivenular inflammatory and demyelinating features illustrated in the images on the Luxol fast blue/periodic acid-Schiff stain for myelin (LFB/PAS in which the LFB is the portion of the stain specific for myelin), are pathognomonic for
acute disseminated encephalomyelitis.
thick-walled spherule containing multiple, small endospores, diagnostic of.
Coccidioides
In multiple system atrophy, glia (especially oligodendroglia) exhibit
cytoplasmic, flame-shaped, silver-positive inclusions that are also immunoreactive for p62, ubiquitin and alpha-synuclein.
severe pontine atrophy and would most likely be seen in the
olivopontocerebellar atrophy (OPCA) form of multiple system atrophy (MSA).
classic histologic feature (shown in the image) is the Negri body, which is a
round or oval eosinophilic inclusion in the cytoplasm of neurons (easiest to find in the Purkinje cells and hippocampal pyramidal cells).
Corticobasal degeneration (CBD) is a
4-repeat tauopathy characterized by tau-immunoreactive lesions, and in particular, numerous tau-positive threads in cerebral white matter and white matter of subcortical nuclei.
Inclusion body myositis has pathologic features of an
inflammatory myopathy, but in addition has features of impaired autophagy, as demonstrated by rimmed vacuoles in muscle cells containing autophagic debris.
Muscular dystrophies in general do not tend to have a significant
inflammatory component.
Steroid myopathy is typified by a
type 2 fiber specific atrophy.
MOA of gabapentin
inhibition of calcium currents via high-voltage-activated channels containing the alpha2delta-1 subunit, leading in turn to reduced neurotransmitter release and attenuation of postsynaptic excitability
VPA increases levels of
gamma-aminobutyric acid and prolongs the recovery of inactivated sodium channels.
teratogenicity due to involvement of male sperm has been observed with ________
teriflunomide
POINT trial (Clopidogrel and Aspirin in Acute Ischemic Stroke and High-Risk TIA) studied secondary stroke prevention in patients with a minor acute ischemic stroke with an NIH stroke scale score of
3 or less or a high-risk TIA with a score of 4 or more on the ABCD2 scale
In this population, the combination of clopidogrel and aspirin for 90 days reduced the rate of major ischemic to
5.0% compared to 6.5% in patients receiving aspirin plus placebo (hazard ratio, 0.75; 95% confidence interval [CI], 0.59 to 0.95; P=0.02), with most events occurring during the first week after the initial event.
Progressive supranuclear palsy (PSP), corticobasal degeneration (CBD) and frontotemporal dementia with parkinsonism (FTDP) have all been associated with abnormalities in the structures of _____ proteins - either mutations with altered amino acid incorporation or hyperphosphorylation.
tau
Beta-amyloid and presenilin mutations are seen in some of the young-onset familial ______ disease.
Alzheimer
Orexin is depleted, but not modified in.
narcolepsy
Definite AD requires the demonstration of pathologic hallmarks on autopsy:
global neuronal atrophy and loss of synapses, deposition of extracellular amyloid protein (A-beta 1-42), and accumulations of intracellular neurofibrillary tangles (NFT).
Unified Parkinson’s Disease Rating Scale motor subscale
PD
By blocking the interaction of alpha4beta1–integrin with the vascular cell adhesion molecule 1 (VCAM-1) ligand on endothelial cells, natalizumab inhibits ____________, reducing CNS inflammation in MS
adhesion and transmigration of activated T-lymphocytes across the blood-brain barrier,
Restoration of immune function may result in
immune reconstitution inflammatory syndrome (IRIS),
Sodium oxybate, the sodium salt of gamma-hydroxybutyrate (GHB), an endogenous substance in the brain, is an effective medication in the
treatment of daytime sleepiness in narcolepsy
Supraphysiologic concentrations appear necessary in order for GHB to bind to GABAB receptors, which is responsible for
sleep induction and an increase in slow-wave sleep
Benzodiazepines and barbiturates facilitate hyperpolarization by positively modulating a subunit of the ________ receptors.
GABA-A
Meperidine and
methylphenidate can lower the seizure threshold in epilepsy patients resulting in
worsening seizures independent of antiepileptic therapy.
Myotonia congenita is an inherited neuromuscular disorder characterized by the
inability of muscles to quickly relax after a voluntary contraction. muscle chloride channel CLCN1 on chromosome 7q35.
mexiletine, which is able to reduce
myotonia
A number of overlapping inherited nondystrophic myotonia syndromes result from mutations to the gene encoding the
voltage-gated sodium channel type IV alpha subunit (SCN4A).
Transient paralysis indicates
hyperkalemic periodic paralysis, and fluctuating myotonia indicates potassium-aggravating myotonia.
_______ is a competitive inhibitor of alcohol dehydrogenase that prevents the formation of metabolites of ethylene glycol and methanol
Fomepizole (4-methylpyrazole)
_____ is a humanized monoclonal antibody against CD52 that causes a long-lasting depletion of lymphocytes and monocytes.
Alemtuzumab. Immune-mediated hypothyroidism or hyperthyroidism occurs in more than 30% of patients treated with alemtuzumab
Nusinersen has been shown to improve motor function in patients with
spinal muscular atrophy (SMA).
SMA is most commonly associated with mutations in the
survival motor neuron 1 (SMN1) gene.
SMN2 contains a
C-to-T mutation in exon 7 that redirects alternative splicing to exclude exon 7 and leads to an unstable mature protein that cannot substitute for mutant SMN1.
Nusinersen is an antisense oligonucleotide that inhibits the splicing of
exon 7 on the SMN2 gene resulting in increased levels of stable SMN protein.
______ is a monoclonal antibody that binds specifically to the calcitonin gene-related protein receptor
Erenumab. Galcanezumab, eptinezumab, and fremanezumab are other newly-developing monoclonal antibodies that bind to the calcitonin gene-related protein ligand.
Bupropion inhibits norepinephrine and dopamine reuptake through this channel and thus can inhibit uptake of the radiolabeled tracer I-123 Ioflupane.
This causes the DaT scan to appear falsely positive.
Approximately 10% of patients with NMOSD present with
intractable nausea, vomiting, and hiccups.
Aquaporin-4 water channel is highly expressed on astrocytic foot processes in
circumventricular regions of the brainstem (area postrema, subfornical organ (SFO), organum vasculosum lamina terminalis (OVLT), all regions that lack a blood-brain barrier (BBB)
The absence of BBB in these areas may result in preferential entry of aquaporin-4 antibody in patients with NMOSD, producing a
unique variety of symptoms referable to these regions.
Involvement of the area postrema produces intractable nausea, vomiting, and hiccoughs, whereas SFO/OVLT lesions manifest with
hypothalamic dysfunction (e.g. hypersomnolence, narcolepsy, and SIADH).
numerous case reports of the efficacy of deep brain stimulation of the ______ in the treatment of cluster headache.
posterior hypothalamus
_________ appeared effective in a small randomized control trial of the treatment of intractable cluster headache but this has not been FDA-approved.
percutaneous stimulation to the sphenopalatine ganglion
The global loss of sensory nerve conduction responses suggests a _____ instead of a length dependent axonal sensory neuropathy.
neuronopathy
Causes of a sensory neuronopathy include
Sjogren syndrome, paraneoplastic syndrome usually with an anti-HU antibody, pyridoxine intoxication (al least 200 mg per day), a variant of Guillain-Bare syndrome, and with platinum-based chemotherapies
Bupropion can reduce the seizure threshold in 1 out of 1000 patients.
However, in patients with bulimia and anorexia nervosa, the seizure risk may be particularly higher.
narcolepsy
(excessive daytime sleepiness, hypnagogic hallucinations, and cataplexy.
Primary narcolepsy is a
putative autoimmune disorder in which there is loss of hypocretinergic neurons in the lateral and preforniceal hypothalamus.
Hypocretin deficiency results in
loss of centrally mediated motor activation that occurs in response to emotional stimuli, producing cataplexy.
Patients with narcolepsy have
reduced levels of hypocretin in CSF (< 110 pg/ml).
Wilson’s disease is an autosomal recessive disease associated with
mutations of the copper-transporting ATPase gene on chromosome 13q14.3.
Serum total copper is low in many patients and urinary copper excretion is always raised. Definitive investigation is a liver biopsy with measurement of copper concentration
Wilson’s. D-penicillamine with pyridoxine is the gold standard of treatment.
Aberrant hyperactivity of mammalian target of rapamycin (mTOR) is caused by a mutation in one of the two TSC genes, TSC1 and TSC2, which results in cellular proliferation and tumor growth.
The use of mTOR inhibitors, particularly everolimus, has been shown to reduce both SEGA size and seizure frequency.
Surveillance for SEGA by imaging study is therefore recommended. mTOR inhibitors also may be useful in treating
renal angiomyolipomas in patients with TSC.
Dabigatran, an FDA-approved oral anticoagulant, is a
direct thrombin inhibitor
Autoimmune necrotizing myopathy has been discovered in patients using statins.
The autoantibody is directed against HMG CoA reductase enzyme. Electromyographic changes are consistent with active myopathic process and MRI frequently reveals muscle edema
Statin-associated autoimmune necrotizing myopathy typically requires _____ therapy.
immunosuppressive
Andexanet alfa is a specific reversal agent that is designed to neutralize the
anticoagulant effects of both direct and indirect factor Xa inhibitors. Andexanet is a recombinant modified human factor Xa decoy protein that is catalytically inactive but that retains the ability to bind factor Xa inhibitors in the active site with high affinity
Idarucizumab is a humanized monoclonal antibody fragment that has been developed as a specific
reversal agent for dabigatran.
Excessive zinc ingestion is a well-recognized cause of
copper deficiency.
Zinc causes an upregulation of metallothionein production in the enterocytes. Metallothionein is an intracellular ligand, and copper has a higher affinity for metallothionein than zinc.
Copper displaces zinc from metallothionein, binds preferentially to the metallothionein, remains in the enterocytes, and is lost in the feces as the intestinal cells are sloughed.
Subsequent copper deficiency is recognized caused of subacute combined degeneration, similar to that associated with
B12 deficiency.
The use of anticholinergic agents such as trihexyphenidyl in Parkinson disease (PD) is typically reserved for
younger patients (under 60 years old) with tremor-predominant dysfunction. Anticholinergic agents should not be prescribed to older patients and patients with dementia due to their wide adverse side effect profile, including cognitive dysfunction, urinary retention, dry mouth, and gastrointestinal disturbances.
Autoimmune autonomic ganglionopathy (AAG) is characterized by prominent and selective involvement of the peripheral autonomic nervous system.
Patients typically develop generalized autonomic failure including orthostatic hypotension, anhidrosis, and parasympathetic dysfunction.
Purkinje cells, which are the _____ cells for the cerebellum. The MRI scan of the brain may be normal.
output
Anti-Yo is the anti-Purkinje cell antibody and reacts only with Purkinje cells.
Patients with anti-Yo have a gynecological cancer, ovarian or breast 90% of the time.
Anti-Hu reacts with nearly all neurons and is commonly associated with
sensory neuropathy and encephalomyeloneuropathy.
The half-life of apixaban is 12 hours, requiring at least
48-hour discontinuance for safe administration of rtPA in this setting.
Dalfampridine is a potassium-channel blocker that improves nerve conduction along centrally demyelinated axons and has been demonstrated to
improve ambulation speed in approximately one-third of patients with multiple sclerosis
Dalfampridine risk
The drug carries a 0.2% risk of seizures, which is usually associated with toxic blood levels
Lewy body dementia, Parkinson disease, and multiple system atrophy are all associated with ______, which may present up to decades prior to the onset of the neurodegenerative illness.
REM behavior disorder. Disorders are all characterized by abnormal deposition of alpha-synuclein in the cytoplasm of neurons and glial cells and are grouped histopathologically as synucleinopathies.
The treatment of choice for REM behavior disorder is ______
clonazepam
Topamax has been known to cause a potentially serious condition known as
metabolic acidosis (an increase of acid in the blood).
_______ syndrome is a sleep disorder predominant in adolescent males with bouts of excessive sleeping up to 18 hours per day in episodes lasting 7-14 days and associated with hypersexual behavior, either anorexia or hyperphagia, feeling of depersonalization and cognitive issues
Kleine-Levin. Hypocretin and orexin levels are reduced during episodes. Treatment is with either lamotrigine or lithium.
Cold temperatures cause slowing of conduction of the action potential.
This results in slowing of conduction velocity, prolongation of distal motor latency, and increase in size of CMAP and SNAP, due to reduction in phase cancellation amongst the axons in the nerve.
REM sleep behavior disorder (RBD).
RBD is characterized by abnormal motor activity, often associated with frightening and violent dreams and occur during REM sleep.
small fiber axonal neuropathy secondary to diabetes may have
normal nerve conduction studies/EMG but autonomic testing may be abnormal.
For absence seizures, _______ is still the best activation procedure for bringing out abnormalities on the EEG.
hyperventilation
Patients with myotonia congenita have normal muscle strength and bulk with myotonia as the prominent symptom and sign. This is a ______ channelopathy.
chloride
Lesions proximal to dorsal root ganglia, like radiculopathy, have
normal sensory nerve action potentials.
abductor pollicis brevis muscle is innervated by the _____ nerve with radicular derivation from C8 and T1.
median
first dorsal interosseous muscles are innervated by the
ulnar nerve and is supplied by radicular contributions from C8 and T1.
extensor indicis proprius muscles are innervated by the radial nerve and is supplied by
radicular contributions from C8
innervation of the short head of the biceps femoris and anterior tibialis muscles both come from the _____ division of the sciatic nerve.
peroneal
Somatosensory evoked potentials record activity in the
dorsal column/medial lemniscal sensory pathways
The ventral spinocerebellar tract ascends to the midbrain then enters through the
superior cerebellar peduncle.
An occipital lesion may cause an asymmetric response to eye opening
Bancaud phenomenon
lesion of the peroneal division of the sciatic nerve, the short head of the biceps femoris muscle will show evidence of denervation in addition to the
tibialis anterior and peroneus longus muscles.
Sparing of gluteus medius argues against ____ radiculopathy
L5
saw-tooth waves are seen in ____ sleep
REM
Generalized delta is seen in ____ while positive occipital sharp transients of sleep are a benign variant of non-REM sleep.
Stage 3
Sensory responses are affected in lesions distal to the dorsal root ganglion (i.e. plexopathies) while they are spared in lesions
proximal to the dorsal root ganglion (i.e. radiculopathies).
Pompe disease, infantile acid maltase deficiency, is an autosomal recessive glycogen storage disorder that causes
generalized hypotonia, cardiomyopathy, hepatomegaly and macroglossia. Needle EMG shows myopathic features and electrical myotonia without evidence of clinical myotonia.
Myotonia congenita is an autosomal dominant disorder associated with
muscle hypertrophy and myotonic discharges on needle EMG.
Congenital myotonic dystrophy presents with severe hypotonia, facial diplegia, and dysphagia, but
myotonia is not seen at birth
Nemaline myopathy causes proximal weakness with cardiomyopathy, but
myotonic discharges are not seen on needle EMG.
Spindles are generated within the thalamus in the
reticular neurons.
Ethosuximide, used to treat absence seizures, binds to _____ in the thalamus.
calcium channels
______ assess the entire length of the motor axon and can be used as a good internal control for other nerve conduction abnormalities.
F waves. They may have their greatest usefulness in identifying early polyradiculopathy such as seen in Guillain-Barre syndrome (GBS).
During auditory evoked potential recording, wave I represents the
distal action potential of cranial nerve VIII.
Electrocerebral inactivity (ECI) is defined as
“no EEG activity over 2 microvolts.”
_______ is the most sensitive diagnostic test for myasthenia gravis
Single fiber EMG (SFEMG). In generalized disease, SFEMG examination of a weak muscle demonstrates increased jitter in more than 90% of cases.
As the number of muscle fibers per motor unit increases, MUAPs become prolonged in duration, with a high amplitude, and polyphasic.
nearly always imply chronic neuropathic disease (ie, disorders of the anterior horn cell, nerve root, or peripheral nerve).
Long duration, high amplitude, polyphasic MUAPs are never seen in ____ conditions.
acute
_____ are a benign phenomenon in the EEG and are seen over posterior and temporal head regions during drowsiness and light sleep.
14- and 6-per-second positive spikes
Nerve conduction studies with temporal dispersion, conduction block, and slow conduction are seen in _________
chronic inflammatory demyelinating polyneuropathy
In hereditary motor and sensory neuropathy (Charcot-Marie-Tooth disease), there are slow latencies and nerve conduction velocities, but no
temporal dispersion or block
In amyotrophic lateral sclerosis, nerve conduction studies may be normal or with
decreased compound muscle action potential amplitudes.
_____ are normal in facioscapulohumeral dystrophy and myasthenia gravis.
Nerve conduction studies
EEG findings in Creutzfeldt-Jakob disease would be
repetitive, generalized 1 Hz sharp waves.
presence of periodic lateralized sharp wave discharges in a patient with a recent febrile illness and onset of seizures would strongly suggest
herpes simplex encephalitis
has juvenile myoclonic epilepsy EEG demonstrates
4-6Hz spike wave discharges, polyspikes and a normal background.
Breach rhythm is seen on EEG with a skull defect. It appears as
accentuation or increased amplitude of rhythms, especially theta, alpha, and beta, underlying the breach in the skull
Positive occipital sharp transients of sleep (POSTS) are seen as a
sharp positive discharge maximal in the occipital regions.
Congenital myasthenic syndromes have presynaptic defects of
ACH packaging and release, deficiency of endplate acetylcholinesterase, and postsynaptic defects of the ion channel or the number of ACH receptors.
combination of a history of cataplexy with a short mean latency on a multiple sleep latency test (MSLT) is sufficient to make a diagnosis of narcolepsy, even in the absence of
sleep-onset REM on an MSLT. Cataplexy may present up to one year before the onset of Sleep-onset REM periods (SOREM) on MSLT.
Alpha (8-11Hz) patterns can be seen in comatose patients and in 3 different types of conditions
In anoxic encephalopathy usually secondary to cardio respiratory arrest alpha patterns are diffusely seen with a frontal predominance. In toxic encephalopathies this pattern is superimposed with beta frequencies.In locked-in states the alpha pattern is posteriorly dominant, reactive to sensory input and photic driving may be seen.
involvement of the femoral innervated muscles with sparing of obturator innervated muscles points to a _____ as the most likely diagnosis.
femoral mononeuropathy
A marked increase in CMAP amplitude (typically greater than 100%) follows
10 seconds of intense isometric exercise.
clinical features of LEMS include
proximal muscle weakness (often more significant in the lower extremities) with decreased deep tendon reflexes
right femoral nerve innervates
quadriceps muscle and mediates the sensory and motor portions of the knee reflex
Subacute sclerosing panencephalitis has an EEG consistent with high amplitude repetitive sharp-slow wave complexes with high amplitudes recurring between
4-15 seconds
