Neurobio physio Flashcards
1
Q
Which gene is mutated in Sturge-Weber syndrome?
A
GNAQ
2
Q
Define STURGE of Sturge-Weber
A
Sporadic, Tram track calcifications, Unilateral port-wine stain on V1/V2 region of face, Retardation (intellectual disability), Glaucoma and GNAQ gene, Epilepsy
3
Q
Describe the HAMARTOMAS mnemonic in Tuberous Sclerosis
A
Hamartomas in CNS and skin Angiofibromas Mitral regurgitation Ash-leaf spots Rhamdomyomas Tuberous Sclerosis Autosomal D(O)minant Mental retardation renal Angiomyolipoma Seizures, Shagreen patches
4
Q
Neurofibromatosis I is inherited as
A
Autosomal Dominant
5
Q
Individuals with Tuberous Sclerosis have an increased incidence of which neural tumor?
A
Subependymal astrocytomas
6
Q
What is the function of NF1?
A
tumor suppressor gene that negatively regulates RAS
7
Q
Sturge Weber sx and Neurofibromas are both derived from which progenitors?
A
Neural crest cells
8
Q
Von Hippel Lindau disease causes which three tumors?
A
Hemangioblastomas, bilateral renal cell carcinomas, and pheochromocytomas
9
Q
Describe the histology of glioblastoma multiforme
A
“Pseudopalisading” pleomorphic tumor cells bordering areas of necrosis. Stain for GFAP
10
Q
Is glioblastoma multiforme benign or malignant?
A
malignant
11
Q
Which cells do meningiomas typically arise from?
A
Arachnoid cells
12
Q
How can hemangioblastoma lead to polycythemia?
A
Tumor produces erythropoetin
13
Q
Which disease is affiliated with hemangioblastomas?
A
Von Hippel Lindau
14
Q
Where do you usually find hemangioblastomas?
A
Cerebellum (expect ipsilateral sx with balance, coordination, ataxia, etc)
15
Q
Where do you typically find Schwanomas?
A
Cerebellopontine angle
16
Q
Which nerve do Schwannomas typically localize to?
A
CN VIII (expect hearing loss)
17
Q
Bilateral vestibular schwannomas can be attributed to which condition?
A
NF-2
18
Q
Where do oligodendrogliomas typically localize to?
A
Frontal lobes
19
Q
Describe the histology of oligodendrogliomas
A
“Chicken wire” capillary pattern with “fried egg” cells
20
Q
Which part of the brain do you typically find glioblastoma multiforme in?
A
Cerebral cortex
21
Q
In children, where do you typically find astrocytomas
A
posterior fossa (cerebellum)
22
Q
What is the prognosis for medulloblastoma in a child?
A
It is highly malignant, poor prognosis; can form noncommunicating hydrocephalus by compressing 4th ventricle
23
Q
What is the prognosis of ependymal tumors in a child?
A
Poor, can cause hydrocephalus
24
Q
Describe the histology of ependymomas
A
perivascular rosettes
25
Where is a craniopharyngioma typically found
supratentorial region; derived from remnants of Rathke pouch
26
Describe histopathology of craniopharyngioma
"Motor oil" like cholesterol cysts found within tumor
27
What is Parinaud syndrome?
Vertical gaze palsy, typically due to pinealoma
28
What is the germ cell origin of Pinealomas
Germinomas
29
What is the most common pinealoma
Prolactinoma
30
Which structure can a subfalcine herniation compress?
Anterior cerebral artery
31
What are the complications of a downward transtentorial herniation?
Downward displacement of brainstem, rupture of paramedian basilar artery branches, hemorrhages, death
32
What are the complications of an uncal herniation?
CN III palsy (mydriasis and down and out eye); ipsilateral PCA compression (contralateral homonymous hemianopia with macular sparing)
33
What is the complication of a cerebellar tonsillar herniation into the foramen magnum
Coma and death when compressing brainstem
34
Which electrolyte imbalances can promote seizures?
Hypogmagnesemia and hypocalcemia
35
Segmental axonal demyelination is seen in which condition
Guillan-Barre
36
Lambert-Eatoon Syndrome is associated with which malignancy?
Lung cancer
37
Perifascicular muscle inflammation is seen with which disease?
Dermatomyositis
38
Which compound is deficient in CSF for pts with narcolepsy?
Hypocretin-1 (Orexin A) and Hypocretin-2 (Orexin-B)
39
Define cataplexy
Conscious, brief episodes of sudden bilateral muscle tone loss triggered by emotions like laughter or joking
40
Where are hypocretin 1 and 2 secreted?
Lateral hypothalamus
41
What is the function of hypocretin (orexin)?
Wakefulness and inhibition of REM sleep-related phenomena
42
Low CSF levels of 5-hydroxyindole-acetic acid is associated with
impulsive, destructive behaviors (aggression, suicide, violence)
43
CSF elevation of 14-3-3 protein is diagnostic of
Cretuzfeldt-Jakob disaese
44
Melatonin levels in CSF are associated with
Progression of Alzheimer's disease
45
Four major symptoms of cavernous sinus thrombosis
Headache, fever, diplopia (ptosis) and ocular muscle paralysis
46
Which cranial nerves traverse the cavernous sinus?
III, IV, VI, V1 and V2
47
What can cause cavernous sinus thrombosis?
Infections from medial third of face, sinuses or teeth (S aureus, strep, Mucor/Rhizopus)
48
Findings of jugular foramen lesions (Vernet syndrome)
Dysphagia, hoarseness, loss of gag reflex on ipsilateral side (CNs IX, X, XI defects)
49
Which neurotoxins inhibit Na+ channels and depolarization?
Tetrodotoxin (puffer fish)
| Saxitoxin (dinoflagellates in red tide)
50
Which toxins bind Na+ channel and cause persistent depolarzation?
Ciguatoxin (exotic fish, Moray eel)
| Batrachotoxin (South American frogs)
51
Symptoms of tetrodotoxin poisoning
rapid onset dizziness, weakness, loss of reflexes, parasthesias of face, nausea, vomiting, diarrhea
52
What is the pyriform recess?
small cavities that lie on either side of laryngeal orifice; foreign bodies (fish bones) can become lodged here
53
Which nerve has the potential to get injured in the pyriform recess
Internal laryngeal nerve (CN X)
54
Symptoms of a internal nerve injury
Loss of cough reflex (sensory and autonomic fibers are lost)
55
Which nerves mediate the gag reflex?
CN IX (afferent) and CN X (efferent)
56
Afferent and efferent nerves in carotid sinus reflex
IX (afferent) and X (efferent)
57
Afferent and efferent fibers in Vestibulo-ocular reflex (eye movements with head movement)
VIII (afferent), III, IV, VI (efferent)
58
Jaw jerk reflex nerves
V3 (afferent and efferent)
59
Corneal reflex nerves
V1 (afferent) VII (efferent)
60
Which nerve mediates salivation?
CN IX parasympathetic fibers (synapse in otic ganglion)
61
What is the auriculotemporal nerve a branch of and what does it do?
CN IX, innervate parotid gland for salivation
62
What is believed to cause the "on--off" phenomenon of drug responses in Parkinson's Disease?
Progressive nigrostriatal neurodegeneration, making drug responses unpredictable
63
How does M3 stimulation in vascular smooth muscle induce relaxation/dilation?
NO synthesis, which diffuses in to vascular smooth muscle and activates cGMP, which activates myosin light chain phosphatase
64
M3 activation via ACh in all other target organs besides peripheral vasculature leads to
smooth muscle contraction (increase IC calcium)
65
How does M2 stimulation on cardiomyocytes lead to decreased inotropy and chronotropy?
bind Gs, decrase cAMP and open K+ channels
66
What is Cushing triad
hypertension, bradycardia, respiratory depression
67
Where is the red nucleus located
midbrain tegmentum, pons
68
Which lesion causes decerebrate (extensor) posturing
Damage at or below red nucleus (pons)
69
Which lesion causes decorticate (flexor) posturing?
Neural structures above red nucleus (cerebral hemispheres, internal capsue) due to loss of inhibition of red nucleus and hyperactivity of limb fleexors
70
What is the purpose of the Romberg test?
Proprioception test that distinguishes sensory from cerebellar ataxia.
71
What does a positive Romberg sign (eyes closed) indicate?
Sensory ataxia (defects in posterior column or peripheral nerves)
72
What are two common causes of posterior column degeneration?
Tabes dorsalis (syphillis) and B12 deficiency
73
How is cerebellar function/motor coordination examined
rapid alternating movements, finger-to-nose, heel-to-shin
74
How is the parietal association cortex tested
Draw a clock or bisect a horizontal line
75
What is the common location of a cluster headache?
Behind one eye and around nostril
76
How long does a cluster headache usually last
15-90 minutes
77
Who is more prone to getting cluster headaches
males > females
78
Nasal congestion and tearing are common associated symptoms for which type of headache
Cluster
79
Auras, photophobia, nausea are associated with which headache
Migraine
80
What is the location of migraines
Unilateral
81
Pulsatile and throbbing pain is characteristic of which headache
Migraine
82
Excruciating, sharp and constant pain is characteristic of which headache
Cluster
83
Dull, tight and persistent pain is characteristic of which headache
Tension
84
Females are more likely to get which type of headaches?
Migraine and tension
85
Family history is associated with which headache?
Migraine
86
Stress can lead to which bilateral headache?
Tension
87
Phenylalanine hydroxylase is mutated in which condition?
PKU
88
Presentation of PKU
Severe developmental and intellectual disabilities, seizures, abnormal pallor of chatecholaminergic brain nuclei (locus ceruleus, substantia nigra, vagal nucleus dorsalis)
89
Which NTs cannot be made in PKU?
Tyrosine, Dopamine, NE/E
90
What causes the musty odor in PKU?
Accumulation of abnormal phenylalanine metabolites
91
What causes hypopigmentation of skin, hair, eyes and brain in PKU?
Phenylalanine inhibitory effect on melanin
92
Presentation of dopamine hydroxylase deficiency
ptosis, orthostatic hypotension, hypoglycemia and hypothermia
93
How does normal pressure hydrocephalus present?
Enlarged ventricles in setting of normal ICP
94
What is hydrocephalus ex vacuo
Normal ICP and increased dilatation of ventricles secondary to cortical atrophy (elderly patients with dementia)
95
What is pseudotumor cerebri
elevated ICP in young overweight women
96
Which structures traverse the optic canal
Opthalmic artery, central retinal vein and CN II
97
Which structures traverse the superior orbital fissure?
CN III, IV, V1, VI, opthalmic vein and sympathetic fibers
98
Which structure traverses the foramen rotundum?
CN V2
99
Which structure traverses through foramen ovale?
CN V3
100
Which structures traverse through foramen spinosum?
middle meningeal artery and vein
101
The Internal Acoustic meatus contains which CNs
CN VII VIII
102
CN IX, X, XI, and jugular vein cross through which foramen?
Jugular foramen
103
The hypoglossal canal carrie which nerve
CN XII
104
The foramen magnum carry which nerves
CN XI, brainstem and vertebral arteries
105
Where is the optimal site for a femoral nerve block?
Inguinal crease at lateral border of femoral artery
106
List 4 UMN signs
Spastic paralysis, clasp-knife rigiditiy, hyperreflexia, Babinski sign
107
4 signs of LMN
Flaccid paralysis, hypotonia, hyporeflexia, muscle atrophy and fasciculations (spasms)
108
Pupillary light reflex pathway
1) CN II (optic nerve) receives input--> 2) Synapses onto 2* axon at Edinger-Westphal--> 3) Bilateral synapse onto pretectal nucleus (both eyes receive input)--> 4) Bilateral efferent output via CN III (pupillary constriction)
109
Corneal reflex afferent and efferent
Afferent: CN V1; Efferent: CN VII
110
Where are the lesions in conus medularis syndrome
L2
111
Flaccid paralysis of bladder and rectum, impotence and saddle (S3-S5) anesthesia suggest
Conus Medullaris syndrome
112
Low back pain radiating to one or both legs, saddle anesthesia, loss of anal sphincter reflex, bowel and bladder dysfunction and loss of ankle-jerk reflex with plantar flexion weakness suggest
Cauda equina syndrome
113
Evagination of roof of developing mouth in buccopharyngeal membrane that gives rise to anterior pituitary; cysts and remnants cause craniopharyngiomas
Rathke pouch
114
Why can glucose therapy without thiamine (such as in a homeless alcoholic) worsen Wernicke encephalopathy?
Thiamine is a cofactor needed for glucose metabolism. In thiamine deficiency, providing glucose exacerbates the deficiency worsening symptoms of confusion, disorientation, encephalopathy
115
Tumors of this gland in the brain cause Parinaud syndrome (vertical gaze palsy, absent light reflex, impaired convergence)
Pineal gland (Pinealomas)
116
Why do Pinealomas result in headache, nausea and vomiting?
Noncommunicative hydrocephalus (interrupts cerebral aqueduct)
117
Which cancers stain positively for GFAP
Astrocytomas, ependymomas, oligodendrogliomas
118
Which cancers stain positively for synaptophysin?
Neurons, neuroendocrine and neuroectodermal cells
