Neuro Step 1 Flashcards
In what disorders are dopamine levels increased?
schizophrenia
In what disorders are dopamine levels decreased?
depression & Parkinson disease
What are the four major dopaminergic pathways?
Mesocortical pathway, mesolimbic pathway, nigrostriatal pathway, tuberoinfundibulnar pathway
Describe the mesocortical pathway. What is the result of blocking this?
Ventral tegmental of the midbrain -> cortex
increased negative symptoms of schizophrenia
Describe the mesolimbic pathway. What is the result of blocking this?
Ventral tegmental of midbrain -> limbic system
Relieves positive symptoms of schizophrenia
Describe the nigrostriatal pathway. What is the result of blocking this?
Substantia nigra pars compacta -> neostriatum
Parkinson Disease
Describe the tuberoinfundibular pathway. What is the result of blocking this?
Arcuate nucleus of hypothalamus -> pituitary
Increased release of prolactin from anterior pituitary (hypogonadism, which manifests as amenorrhea in women and decreased libido in men)
In what disorders are norepinephrine levels increased?
anxiety/mania
In what disorders are norepinephrine levels decreased? Where is NEpi produced?
depression
locus ceruleus
In what disorders are serotonin levels decreased? Where is serotonin produced?
anxiety and depression
Raphe nucleus
What disorder is associated with decreased levels of ACh? Degeneration of what structure would be found?
Alzheimer’s Disease
basal nucleus of Meynert
In what disorders are GABA levels decreased? Where is it produced?
anxiety & Huntington's disease nucleus accumbens (produced from glutamate and VitB6)
Forebrain (prosencephalon) develops into what?
Telencephalon -> cerebral hemispheres, basal ganglia, hippocampus, amygdala
Diencephalon -> thalamus, hypothalamus, optic nerves, and tracts
Midbrain (mesencephalon) develops into what?
Mesencephalon -> midbrain
Hindbrain (rhombencephalon) develops into what?
Mesencephalon -> Cerebellum & pons
Myelencephalon -> medulla
What cartilage, muscle, and nerve structures develop from the first pharyngeal arch?
M&T structures
Cartilage -
Meckel's cartilage
- mandibular ligament
- mandible
- malleus & incus
Muscle -
Muscles of Mastication
- masseter
- medial pterygoid and lateral pterygoid muscles
- temporalis
mylohyoid
tensor tympani
tensor veli palatini
Anterior 2/3 of tongue
Nerves
Mandibular & Maxillary branches of the trigeminal nerveWhat disorder happens if neural crest cells fail to migrate to the 1st pharyngeal arch?
Treacher Collins syndrome
What cartilage, muscle, and nerve structures develop from the second pharyngeal arch?
S structures Cartilage - Stapes Styloid process Stylohyoid ligament Lesser horn of the hyoid Muscle - Muscles of facial expression Stapedius Stylohyoid Nerve - CN Seven (innervates the muscle of facial expression)
What cartilage, muscle, and nerve structures develop from the third pharyngeal arch?
"pharyngeal" Muscle - stylopharyngeus Nerves - Glossopharyngeal (CN IX)
What cartilage, muscle, and nerve structures develop from the fourth and sixth pharyngeal arches?
“cricothyroid & larynx”
Cartilage -
cricoid cartilage, thyroid cartilage, cartilage of the larynx
Muscles -
cricothyroid muscle (4th)
pharyngeal muscles (swallowing) (4th)
rest of the laryngeal mm. (speech) (6th)
Nerves -
CN X
superior laryngeal (swallowing and cricothyroid m)
recurrent laryngeal nerve (6th arch) (speech)
Forebrain anomalies
meroencephaly anencephaly meroanencephaly - incompatible with life holoprosencephaly -> hemispheres of the brain fail to separate at midline
What causes cycloplegia and cleft lip & palate?
sonic hedgehog gene mutations
severe fetal alcohol syndrome
patau syndrome (trisomy 13)
What is Dandy Walker syndrome?
enlarged posterior fossa
cerebellar vermis fails to develop
Dilation of the 4th ventricle
associated with hydrocephalus & spina bifida
What are Chiari malformations?
Hindbrain abnormality -> part of the cerebellum herniates downward through foramen magnum
Chiari I - mildest; only tonsils herniate; may cause syringomyelia
Chiari II - lombosacrale myelomeningocele, more significant herniation of tonsils and vermis; can have hydrocephalus
What germ layers come from the pharyngeal arches, pouches, and clefts?
arches - mesoderm
clefts - ectoderm
pouches - endoderm
What forms from the 1st pharyngeal pouch?
Eustachian tubes, middle ear cavity, mastoid air cells
What forms from the 2nd pharyngeal pouch?
epithelial lining of the tonsils
What forms from the 3rd pharyngeal pouch?
inferior parathyroid glands and thymus
What forms from the 4th pharyngeal pouch?
superior parathyroid glands
What forms from the 1st pharyngeal cleft?
external auditory meatus
What forms from the 2nd-4th pharyngeal clefts?
temporary cervical sinuses
If one does not obliterate, patient will have a pharyngeal cleft cyst in the lateral neck
What makes a thyroglossal duct cyst?
failure of thyroglossal duct to be obliterated
will be found midline and will move when swallowed
What is DiGeorge Syndrome?
22q11 deletion
abnormal development of the 3rd and 4th pharyngeal pouches -> absent thymus and parathyroid glands
immunodeficient and hypocalcemic
What does the premotor cortex do?
planning & guiding movement based on sensory input
What does the arcuate fasciculus do?
Connection between Broca’s and Wernicke’s areas
What do the frontal eye fields do?
eye movements and scanning
What structures are contained inside the carotid sheath?
common carotid artery, jugular vein, vagus n
What is expressive dysprosody?
inability to express emotion or inflection in speech
non dominant cortical lesion corresponding to broca’s area
What is receptive dysprosody?
inability to comprehend emotion or inflection in speech
Nondominant cortical lesion corresponding to Wernicke’s area
What is Gerstmann syndrome?
lesion of the dominant angular gyrus (usually left) (parietal lobe just posterior/superior to Wernicke’s area), resulting in:
agraphia - inability to write
acalculia - inability to do mathematical calculations
right-left disorientation
finger agnosia - inability to distinguish fingers
What is hemispatial neglect syndrome?
lesion of the non dominant angular gyrus (usually right side)
results in neglect of the body or surrounding contralateral to the lesion
What artery is damaged in Broca’s or Wernicke’s aphasia?
MCA
What artery is damaged in lower extremity sensory and/or motor loss?
ACA
What artery is damaged in unilateral sensory and/or motor loss in the face and arm?
MCA
What are the areas of the brain most susceptible to damage?
cerebellum, neocortex, hippocampus, watershed areas
What disorders are berry aneurysms associated with?
Ehlers Danlos and ADPKD
Where is the most common site for berry aneurysms?
junction of anterior communicating and ACA
What drug is used in a subarachnoid hemorrhage to prevent vasospasm?
nimodipine
What occurs with bilateral lesions of the hippocampus?
anterograde amnesia - inability to make new memories
What occurs with bilateral lesions of the mammillary bodies?
wernicke-korsakoff syndrome - confusion, ataxia, nystagmus, ophthalmoplegia, memory loss (anterograde and retrograde amnesia), confabulation, personality changes
can occur with alcoholics deficient in thiamine (Vit B1)
What occurs with bilateral lesions of the amygdala?
kluver-bucy syndrome - disinhibited behavior (hyperphagia, hypersexuality, hyperorality) - lose fear response
can occur with HSV-1 encephalitis
What is intraventricular hemorrhage in the newborn?
hemorrhage into the ventricular system
most common in premature/very low birth weight infants (<32 weeks, <1500g) within the first 72 hours of life
originates from the germinal matrix in the subependymal, sub ventricular zone that gives rise to neurons and glia during development
What cranial nerve deficit is associated with an epidural hematoma?
CN III palsy -> down and out pupil
Which crosses suture lines: epidural hematoma, subdural hematoma, or subarachnoid hemorrhage?
subdural hematoma -> subdural snakes along the skull
You see bloody CSF on lumbar puncture. What is it?
subarachnoid hemorrhage
What artery is commonly damaged in an epidural hematoma?
middle meningeal artery
What are the nuclei of the anterior hypothalamus?
Anterior, suprachiasmatic, preoptic, supraoptic, paraventricular
What is the function of the anterior nucleus of the hypothalamus? What happens with damage to it?
thermoregulation (AC = anterior cooling); damage causes hyperthermia
What is the function of the suprachiasmatic nucleus of the hypothalamus? Where does it receive input from?
Circadian rhythms; retina
What is the function of the prepoptic area of the hypothalamus?
Secretes GnRH
What is the function of the supraoptic nucleus of the hypothalamus? What happens with damage to it?
Secretes ADH (stored in posterior pituitary); damage causes central diabetes insipidus
What is the function of the paraventricular nucleus of the hypothalamus?
Secretes oxytocin (stored in posterior pituitary), secretes CRH, secretes TRH
What are the nuclei of the tuberal hypothalamus?
Arcuate, lateral, ventromedial, dorsomedial
What is the function of the arcuate nucleus of the hypothalamus?
Secretes GHRH, secretes dopamine, pulsatile GnRH secretion, regulates appetite
What is the function of the lateral nucleus of the hypothalamus? What happens with damage to it?
regulates hunger; inhibited by leptin; damage leads to anorexia and weight loss
What is the function of the ventromedial nucleus of the hypothalamus? What happens with damage to it?
Regulates satiety; stimulated by leptin; damage leads to obesity and savage behavior
What is the function of the dorsomedial nucleus of the hypothalamus? What occurs with stimulation of it?
regulates hunger; stimulation leads to obesity and savage behavior
What are the nuclei of the posterior hypothalamus?
posterior and mammillary
What is the function of the posterior nucleus of the hypothalamus? What happens with damage to it?
Thermoregulation (warming); damage causes hypothermia
What is the function of the mammillary nucleus of the hypothalamus? What happens with damage to it?
Memory; damage causes Wernicke-Korsakoff
What structure secretes melatonin?
secreted by pineal gland; produced in darkness; secretion follows circadian rhythm
What structures make up the limbic system?
cingulate gyrus, fornix, hippocampus (memory), septal nucleus, mammillary bodies, amygdala (summation of signals)
Deficiency of what nutrient causes damage to the mammillary bodies?
Vitamin B1 (thiamine)
What are the responsibilities of the limbic system?
Feeding, Fleeing, Fighting, Feeling, and Sex
What cranial nerve exits the skull at the cribriform plate?
CN I
What cranial nerve exits the skull at the optic canal?
CN II (along with the ophthalmic artery)
What cranial nerve exits the skull at the superior orbital fissure?
CN III, CN IV, CN VI, CN V1
What cranial nerve exits the skull at the foramen rotundum?
CN V2
What cranial nerve exits the skull at the foramen ovale?
CN V3
What structure exits the skull at the foramen spinousum?
middle meningeal artery
What cranial nerve exits the skull at the internal auditory meatus?
CN VII, CN VIII
What cranial nerve exits the skull at the jugular foramen?
CN IX, CN X, CN XI, and the jugular vein
What cranial nerve exits the skull at the hypoglossal canal?
CN XII
What structure go through the foramen magnum?
vertebral arteries & spinal root of CN XI (enters the skull to exit through the jugular foramen)
What conditions can result in facial nerve palsy?
Lovely Bella Had An STD (Lyme, Bell’s palsy, HSV/Zoster (#1 cause), AIDS, Sarcoidosis, Tumors, Diabetes
Facial nerve/nucleus lesion leads to:
paralysis of ipsilateral side of entire face
Facial motor cortex lesion leads to:
paralysis of contralateral side of lower face
What are the vagal nuclei?
nucleus solitarius, nucleus ambiguus, dorsal motor nucleus
What is the function of the nucleus ambiguus?
swallowing and speech; receives input from the bilateral corticobulbar tracts & bilateral motor cortices
What is the function of the nucleus solitarius?
visceral sensory information (sensory from pharynx, trachea, esophagus, taste from back of tongue)
What is the function of the dorsal motor nucleus?
sends autonomic (parasympathetic) fibers to heart, lungs, and upper GI
What neurologic deficits can you see with an infection of the cavernous sinus?
cavernous sinus contains: CN 3, 4, 5, and 6
ophthalmoplegia: CN III: eye down and out; CN VI (most susceptible): eye adducts
diplopia
pain or numbness of upper face (CN V)
What is the function of the dorsal column? Where does it decussate? Where does it end?
Ascends
Function: pressure, vibration, fine touch, proprioception
Decussation: medulla -> ascends contralaterally in medial lemniscus
Ends: VPL of thalamus -> sensory cortex
What is the function of the spinothalamic tract? Where does it decussate? Where does it end?
Ascends
Function: Lateral: pain and temperature; Anterior: crude touch, pressure
Decussate: anterior white commissure (1-2 levels above entrance into SC) -> ascends contralaterally
Ends: VPL of thalamus -> sensory cortex
Pain and temp to face = trigeminothalamic tract (runs with spinothalamic tract, but DOES NOT decussate
What is the function of the lateral corticospinal tract? Where does it decussate?
Descends
Function: voluntary movement of contralateral limbs
Decussates: caudal medulla -> descends contralaterally
What artery supplies the medullary pyramids and the medial lemniscus int he medulla?
Anterior spinal artery
What artery supplies the inferior cerebellar peduncle, nucleus ambiguus, and lateral spinothalamic tract in the medulla?
PICA
What spinal tract conveys light touch, proprioception, and vibration sensation?
Dorsal Columns
What spinal tract conveys motor commands from he motor cortex to the body?
Lateral corticospinal and ventral tracts
What spinal tract conveys pain and temp sensation?
Lateral spinothalamic
What spinal tract is important for postural adjustment and head movements?
Vestibulospinal
What spinal tract conveys proprioceptive information to the cerebellum?
Spinocerebellar (dorsal and ventral)
What is the triad of Horner syndrome?
ptosis, mitosis, anhydrosis
Which direction does vertebral disc herniation usually occur? What are the most common spinal levels? What nerve is affected?
posterolaterally; L4-L5 or L5-S1; nerve usually affected is below the level of herniation
What is the dura mater derived from?
mesoderm
What is the arachnoid mater derived from?
neural crest
What is the Pia mater derived from?
neural crest
What is Ebstein anomaly? What causes it?
Displacement of the septal and posterior tricuspid valve leaflets toward the apex -> atrialization of the right ventricle; lithium causes this
What is the hallmark sign of a brainstem lesion?
alternating syndromes: long tract symptoms on one side (motor or sensory problems) and cranial nerve symptoms on the other side (due to interrupting CN nuclei)
What are the four medial/midline structures of the brainstem (first rule of fours)? What happens with a deficit in each?
begin with M:
1. Motor pathways (corticospinal tract)
Deficit: weakness of the C/L arm and leg
2. Medial lemniscus
Deficit: loss of vibration/proprioception/fine touch (C/L arm/leg)
3. Medial longitudinal fasciculus
Deficit: ipsilateral internuclear ophthalmoplegia
4. Motor cranial nerve nuclei
Deficit: 3,4,6,12 CNs - ipsilateral defects of these CNs
What are the four “side” (lateral) structures of the brainstem (second rule of fours)? What happens with a deficit in each?
begin with S:
1. Spinocerebellar tract
Deficit: ipsilateral arm & leg ataxia
2. Spinothalamic tact
Deficit: alteration of pain & temp sensation in C/L arm and leg
3. Sensory nucleus of CN V
Deficit: ipsilateral alteration of pain and temp on face
4. Sympathetic pathway
Deficit: ipsilateral Horner syndrome (ptosis, miosis, anhydrosis)
What are the four cranial nerves that origination in the pons, four below the pons, and four above the pons (two in midbrain)? (third rule of fours)
- CN III, IV - originate in the midbrain (above the pons)
- CN V, VI, VII, VIII - originate in the pons
- CN IX, X, XII - originate in the medulla (below the pons)
What are the four motor cranial nerve nuclei in the midline? (fourth rule of fours)
CN III, IV, VI, XII (CN tracts DO NOT decussate)
What artery supplies the lateral pons?
AICA
What artery supplies the medial pons?
median and paramedic branches of the basilar artery
What artery supplies the lateral medulla?
PICA
What artery supplies the medial medulla?
anterior spinal artery
What is the other name for lateral medullary syndrome? What deficits could you see?
Wallenberg syndrome
- loss of pain and temp sensation over C/L body (spinothalamic tract)
- loss of pain and temp sensation over I/L face (spinal trigeminal nucleus damage)
- Hoarseness, difficulty swallowing, loss of gag reflex (nucleus ambiguus: CN IX and X damage)
- Ipsilateral Horner syndrome (descending sympathetic tract)
- Vertigo, nystagmus, N/V (vestibular nuclei damage) (almost always causes these)
- I/L cerebellar deficits (ataxia, past pointing) (inferior cerebellar peduncle damage) - spinocerebellar tract
What deficits could you see with medial medullary syndrome?
- C/L spastic hemiparesis (pyramid/corticospinal tract damage)
- C/L tactile and kinesthetic defects (medial lemniscus damage) (decreased vibration and proprioception)
- tongue deviation toward the side of the lesion (hypoglossal nucleus/nerve damage)
- Pain and temp sensation generally preserved
What deficits could you see with lateral inferior pontine syndrome?
- I/L facial nerve paralysis (facial nucleus and nerve fiber damage)
- Ipsilateral limb and gait ataxia (damage to middle cerebellar peduncle) - spinocerebellar tract
- I/L loss of pain and temp sensation from the face (spinal trigeminal nucleus and nerve fiber damage)
- C/L loss of pain and temp sensation (damage to spinothalamic tract)
- I/L Horner syndrome (damage to descending sympathetic tract)
- No C/L body paralysis or loss of light touch/vibratory/proprioceptive sensation
What deficits could you see with medial pontine syndrome?
- C/L spastic hemiparesis (corticospinal tract damage)
- C/L loss of light touch/vibratory/proprioceptive sensation (medial lemniscus damage)
- I/L internuclear ophthalmoplegia (damage to MLF)
- Gaze away from side of lesion (damage to pontine gaze center: PPRF)
- I/L paralysis of lateral rectus muscle (damage to abducens nucleus)
- Pain and temp sensation preserved
What is internuclear ophthlamoplegia? What disorders could it be seen in?
caused by a lesion of the MLF. Horizontal nystagmus of one eye with loss of adduction in the opposite eye. Convergence is normal. Will see in MS and medial pontine strokes
What is Weber syndrome?
anterior midbrain infarction resulting from occlusion of the paramedic branches of the posterior cerebral artery.
- Cerebral peduncle lesion: dysphagia, dysphonia, dysarthria (corticobulbar tract damage); C/L spastic hemiparesis (corticospinal tract damage)
- Oculomotor nerve palsy - ipsilateral ptosis, pupillary dilation, lateral strabismus (eye down and out)
What is locked-in syndrome?
bilateral basilar artery stroke; associated with rapid correction of hyponatremia (medial pontine myelinolysis)
consciousness (RAS) spared, quadriplegia, loss of horizontal but not vertical eye movements
What are the features of idiopathic intracranial hypertension?
young obese women
headaches - daily, pulsatile, worse at night or early AM, possible retroocular pain worsened by eye movements, possible N/V
Papilledema
most worrisome sequela is vision loss
Ct scan: no ventricular dilation, no tumor, no mass
elevated ICP (>200 in non obese patients, >250 in obese patients)
How is idiopathic intracranial hypertension managed?
first line pharmacotherapy = acetazolamide
weight loss in obese patients
discontinue inciting agents
What is the treatment for cluster headaches?
sumatriptan or 100% O2 (quickest)
verapamil for prophylaxis
What is the treatment for tension headaches?
NSAIDs (ibuprofen, naproxen, acetaminophen)
What is the treatment for migraines?
triptans (sumatriptan, rizatriptan, zolmitriptan)
What are the adult brain tumors? (5)
- Glioblastoma
- Meningioma
- Schwannoma
- Oligodendroglioma
- Pituitary adenoma
What are the pediatric brain tumors? (4)
- Pilocytic astrocytoma
- Medulloblastoma
- Ependymoma
- Craniopharyngioma
Which brain tumor has pseudopalisading necrosis?
glioblastoma
Which brain tumors are associated with NF2?
schwannoma, meningioma
Which brain tumors are associated with hyperprolactinemia?
pituitary adenoma
Which brain tumors are associated with psammoma bodies?
meningioma
Which brain tumors have a fried egg appearance?
oligodendroglioma
Which brain tumors have perivascular pseudorosettes?
ependymoma
Which brain tumors are associated with bitemporal hemianopia?
pituitary adenoma, cranipharyngioma
Which brain tumor has the worst prognosis of any primary brain tumor?
glioblastoma
Which brain tumors are associated with a child having hydrocephalus?
Medulloblastoma, ependymoma
Which brain tumor is associated with Homer-Wright pseudorosettes?
medulloblastoma
Tuberous sclerosis
Aut Dom, mutations in TSC1 and TSC2 genes (hamartin and tuberin proteins); classic triad: seizures, intellectual disability, angiofibromas
additional findings: hypomelanotic macule (ash-leaf spots), retinal hamartomas, cortical tubers (glioneuronal hamartomas)
tumor associations: renal angiomyolipoma, cardiac rhabdomyoma, astrocytoma
What is the treatment for trigeminal neuralgia?
carbamazepine
What is the treatment for absence seizures?
ethosuximide (valproic acid is 2nd line)
What is the treatment for status epilepticus?
benzodiazepines (diazepam or lorazepam)
What is the treatment for eclampsia?
magnesium sulfate (Benzos 2nd line)
What are the most common causes of seizures in children?
infections, trauma, developmental etiology, metabolic disturbances
Which hypothalamic nucleus is responsible for regulating the sympathetic nervous system?
Posterior
Which hypothalamic nucleus is responsible for regulating the parasympathetic nervous system?
Anterior
What are the findings of Brown-Sequard syndrome?
At level of lesion: LMN signs & pain & temp loss
I/L below lesion: loss of pain and temp, loss of fine touch/proprioception/vibration (dorsal columns), UMN signs
C/L below lesion: loss of crude touch, pain & temp (spinothalamic tract)
What are some of the classic presenting scenarios for MS?
intention tremor, nystagmus, scanning speech (also think of internuclear ophthalmoplegia, bowel/bladder incontinence, and optic neuritis)
What are the classic presenting symptoms of syringomyelia?
loss of pain and temp in cape/shawl pattern bilaterally; hand muscle weakness and atrophy
What causes degeneration of the dorsal columns?
tabes dorsalis
What causes degeneration of the anterior horns of the spinal cord?
poliomyelitis and werdnig-hoffmann disease
What are is spared in occlusion of the anterior spinal artery?
dorsal columns and medial lemniscus
What are the deep nuclei of the cerebellum?
Fast Gerbils Exercise Daily -Fastigial -Globose -Emboliform -Dentate (globose + emboliform = interposed nuclei)
What structure provides the major output pathway from the cerebellum?
superior cerebellar peduncle -> contralateral ventral lateral nucleus of the thalamus
On which side of the body would motor control be affected by a lesion of the cerebellum?
motor control ipsilateral to the side of the lesion would be affected (double C/L)
output from cerebellum -> C/L thalamus -> cortex -> corticospinal tract -> body C/L to cortex (ends up I/L)
What is the function of the vestibulocerebellum? What does a lesion here do?
(also called flocculonodular lobe)
Function: balance and equilibrium
Lesion: disequilibrium, difficulty with balance, truncal ataxia, nystagmus
What is the function of the spinocerebellum? What does a lesion here do?
(medial with vermis)
Function: postural control of trunk, coordination of legs
Lesion: postural instability, broad-based gait
What is the function of the cerebrocerebellum? What does a lesion here do?
(lateral part of hemisphere)
Function: control of extremeties
Lesion: intention tremor, loss of coordination (dysdiadokinesia, dysmetria)
What are the features of essential (familial) tumor?
rapid, fine tremor of head, hands, arms, and/or voice
occurs with both movement and rest
50% of patients have a family history of tremor
Treated with beta blocker (propranolol), primidone (anticonvulsant), or clonazepam
Some patients self medicate with alcohol
What information is relayed by the ventral lateral nucleus of the thalamus?
motor coordination from the cerebellum and basal ganglia -> cortex
What information is relayed by the VPL nucleus of the thalamus?
somatosensory from body -> primary sensory cortex
What information is relayed by the medial geniculate nucleus?
Auditory information from inferior colliculus -> auditory cortex
A patient presents with involuntary flailing movements of one arm. Where is the lesion?
Subthalamic nucleus (hemiballismus)
Glaucoma physical findings
Optic disc atrophy with cupping
Elevated Intraocular pressure
Progressive peripheral visual field loss
Treatment for acute closure narrow-angle glaucoma if delay > 1 hour in seeing ophthalmologist
Timolol, apraclonidine, acetazolamide, mannitol
What are symptoms of a lesion to the C5 and C6 nerve roots?
Erb-Duchenne Palsy - loss of UE lateral rotators - loss of biceps m. - loss of UE abductors (suprascapular n., musculocutaneous n., axillary n.
What are the symptoms of a lesion to the inferior trunk of the brachial plexus?
Klumpke’s palsy
- loss of intrinsic hand mm; claw hand
- sensory loss of the medial arm, forearm, and hand
What sensory area is supplied by the radial nerve?
posterior arm and dorsal side of hand
What sensory area is supplied by the ulnar nerve?
5th digit and half of 4th digit
medial side of pam and dorsal hand
What sensory area is supplied by the median nerve?
lateral palm and first 3 1/2 digits
What sensory area is supplied by the musculocutaneous nerve?
lateral side of the forearm
What sensory area is supplied by the axillary n?
lateral shoulder
What sensory area is supplied by the femoral n?
anterior thigh and medial lower leg
What sensory area is supplied by the obturator n?
medial thigh
What sensory area is supplied by the sciatic n?
Posterior thigh and gluteal regions
entire lower leg except medial aspect
What sensory area is supplied by the tibial n?
sole of the foot
back of the calf (sural n)
What sensory area is supplied but the common fibular n?
lateral lower leg
dorsal side of the foot
What sensory area is supplied by the deep fibular n?
webbing between first and second toes
What is the adaptation, sensation, and location of Merkel receptors?
Adaptation: slow; sensation: static pressure; Location: superficial/hair follicles
What is the adaptation, sensation, and location of Meissner corpuscles?
Adaption: rapid; sensation: light touch; location: superficial
What is the adaptation, sensation, and location of Ruffini receptors?
Adaptation: slow; sensation: pressure/position sense; location: deep/spindle-shaped
What is the adaptation, sensation, and location of Pacinian corpuscles?
Adaptation: rapid; sensation: vibration; location: deep/onion-shaped
What is the adaptation, sensation, and location of free nerve endings?
Adaptation: A-delta: rapid; C-fiber: slow
Sensation: A-delta: sharp pain/cold; C-fiber: dull pain
Location: superficial/everywhere
What CSF changes are present in Guillain-Barre syndrome?
increased protein but normal cell count
What are the classic manifestations of Guillain-Barre syndrome?
ascending symmetric paralysis (w/o sensory loss), facial paralysis, preceded by infection (campylobacter jejuni
Describe the flow of aqueous humor.
produced by the epithelium of the ciliary body
flows from the posterior chamber -> through the pupil -> into the anterior chamber
exits the anterior chamber via the trabecular meshwork (canal of Schlemm)
Acute angle-closure glaucoma
emergency
abrupt onset of pain, headache (temporal, eyebrow), nausea, colored halos, rainbows around light
red, teary eye with hazy cornea and fixed, mid-dilated pupil (not reactive to light) that is firm to palpation
Open-angle glaucoma
common, insidious form; usually bilateral
risk factors: older than 40, African American, family history of glaucoma, myopia, and diabetes
Early stage: asymptomatic, elevated intraocular pressure
Late stage: gradual loss of peripheral vision, permanent blindness if untreated
Classic presentation of a patient with a cataract
usually bilateral
slowly progressive, painless decrease in vision (difficulty driving at night, reading road signs, or reading fine print)
possible disabling glare from sunlight or oncoming headlights at night
near-sightedness is often an early manifestation
What drug classes are used in the treatment of glaucoma?
alpha agonists, beta blockers, cholinomimetics, diuretic, prostaglandins
What is the treatment for dry, age-related macular degeneration?
smoking cessation, antioxidants
What drugs should be used if there is >1 hour delay in seeing an ophthalmologist for acute closure narrow-angle glaucoma?
timolol, apraclonidine, acetazolamide, mannitol
What infections are associated with posterior uveitis?
CMV, toxoplasmosis, cat scratch Dz, psoriatic arthritis, IBD
What infections are associated with anterior uveitis?
reactive arthritis, ankylosing spondylitis, sarcoidosis, juvenile idiopathic arthritis
Wet vs Dry Macular Degeneration
Dry - deposition of yellowish extracellular material in between Bruch membrane and retinal pigment epithelium with gradual decrease in vision
Wet - rapid loss of vision due to bleeding secondary to choroidal neovascularization. Treat with anti-VEGF
Can have cotton wool spots
How is retinal detachment visualized on fundopscopic exam?
crinkling of retinal tissue and changes in vessel direction
What disorders can cause a cherry red spot on the eye?
central retinal artery occlusion
Tay-Sachs disease
Niemann-Pick disease
Other lysosomal storage diseases
What happens with a frontal eye field lesion?
eye deviates toward lesion
What happens with a lesion of the paramedic pontine reticular formation?
eyes deviate away from lesion
What happens with a lesion of the superior colliculus?
paralysis of upward gaze (parinaud’s syndrome)
What will a weber and rinne test be for conductive hearing loss in the R ear?
Weber - lateralizes to R side
Rinne - bone > air (abnormal)
What will a weber and rinne test be for sensorineural hearing loss in the L ear?
Weber - lateralizes to R side
Rinne - air > bone (normal)
What is a cholesteatoma?
overgrowth of desquamated keratin debris within the middle ear space
Acute otitis externa
inflammation/infection of ear canal
pain with manipulation of the ear
most commonly caused by P. aeruginosa or S. aureus
Treatment: irrigation and topical antibiotics
Acute otitis media
bacterial or viral infection fo the middle ear space
diagnosis made by inspection of the tympanic membrane:
- bulging
- middle ear effusion
- erythema
- TM immobility under positive pressure with pneumatic otoscope
most common bacterial causes: S. pneumonia, nontypable H. influenzas, M. catarrhalis
Treament
- antibiotics (amoxicillin, amoxicillin + clavulanic acid, cephalosporins)
-tubes
What is the triad of Meniere’s disease?
intermittent vertigo, tinnitus, and hearing loss
What are the stages of sleep? What waves do they have?
Awake (beta), Relaxed (alpha), N1 (theta), N2 (sleep spindles and K complexes), N3 (delta), REM (beta)
What stage of sleep do you grind your teeth? What stage do you dream? What stage do you have night terrors?
teeth grinding (bruxism): N2
dreaming: REM
night terrors: N3
What sleep changes do you see in the elderly?
decreased REM and slow-wave sleep (N3), increased sleep onset latency, increased early awakenings, increased REM latency (takes longer to get there)
What sleep changes do you see with depression?
decreased slow wave sleep (N3) decreased REM latency increased REM early in sleep cycle increased total REM sleep repeated nighttime awakenings early-morning awakening (terminal insomnia)
What is the treatment for narcolepsy?
avoidance of drugs that cause sleeepiness
scheduled naps (1-2x/day for 10-20 min)
stimulants - modafinil, methylphenidate
If cataplexy, then use venlafaxine, fluoxetine, or atomoxetine
What is the treatment for restless leg syndrome?
check iron levels; pramipexole, ropinirole; gabapentin or pregabalin if pain also
Nocturnal Enuresis
bed-wetting
cannot be diagnosed until age 5; treatment is delayed until age 7
desmopressin (DDAVP) - ADH; enuresis starts again after discontinuation
imipramine (TCA) - decrease N3 time; short-term
Indomethacin (decrease RBF -> decrease GFR -> decrease urine production)
What drugs are used to shorten stage N3 sleep?
Imipramine (TCA) & benzodiazepines
What is the sleep pattern in a patient with narcolepsy?
start with REM sleep instead of N1
Where do neurons of the lateral corticospinal tract synapse prior to exiting the spinal cord to affect movement?
synapse at the cell body of the anterior horn
What information is relayed by the lateral geniculate nucleus of the thalamus?
visual retina -> occipital cortex
What information is relayed by the ventral posterior medial nucleus of the thalamus?
somatosensory from face via trigeminal tract/medial lemniscus
What information is relayed by the ventral anterior nucleus of the thalamus?
motor basal ganglia -> cortex
