Neuro 1 Flashcards
1
Q
What is the most common primary brain malignancy?
A
Glioblastoma (aka grade IV astrocytoma, formerly glioblastoma multiforme)
2
Q
Classic CT/MRI findings in glioblastoma?
A
Butterfly appearance with central necrosis (typical of glioblastoma); heterogenous serpiginous contrast enhancement (typical of high-grade astrocytoma)
3
Q
Patients with brain metastases usually have a duration of symptoms of…?
A
Less than 2 months
4
Q
General site of metastasis in patients with brain mets?
A
Gray-white junction or watershed zones
5
Q
What is the most common cause of spontaneous lobar hemorrhage?
A
Cerebral amyloid angiopathy (especially in adults >60)
6
Q
What causes cerebral amyloid angiopathy?
A
Beta-amyloid deposition in the walls of small- to medium-size cerebral arteries, resulting in vessel wall weakening and predisposition to rupture
7
Q
What is the most common cause of intracranial hemorrhage in children?
A
AV malformation rupture
8
Q
What causes a subdural hematoma and what are some risk factors?
A
Rupture of bridging veins, most commonly from head trauma; advanced age, chronic alcoholism, anticoagulant use
9
Q
How does subdural hematoma appear on non-contrast head CT?
A
Crescent-shaped hyperdensity that crosses suture lines
10
Q
How does ischemic stroke appear on CT scan?
A
Area of hypodensity affecting a vascular distribution
11
Q
What causes an epidural hematoma?
A
Meningeal artery tears, typically due to traumatic head injury
12
Q
How does an epidural hematoma appear on non-contrast head CT?
A
Biconvex hyperdensity that does NOT cross suture lines
13
Q
What causes subarachnoid hemorrhage and how does it present?
A
Ruptured saccular (berry) aneurysms; abrupt onset of severe (thunderclap) headache; focal neuro deficits are uncommon
14
Q
How does subarachnoid hemorrhage appear on CT?
A
Hyperattenuation of the sulci and basal cisterns on head CT
15
Q
Presentation - sudden impairment of consciousness in children age 4-10 without loss of postural tone, occur throughout the day without warning, short (<20 seconds), may be accompanied by simple automatisms (eyelid fluttering, lip smacking, etc.)
A
Absence seizures
16
Q
Absence seizures can usually be provoked by ___.
A
Hyperventilation
17
Q
Dx absence seizures?
A
EEG - 3-Hz spike-wave discharge pattern
18
Q
First-line Rx for absence seizures?
A
Ethosuximide
19
Q
Age of presentation of myasthenia gravis in men and women?
A
Women - 2nd to 3rd decade
Men - 6th to 8th decade
20
Q
Presentation of myasthenia gravis?
A
Fluctuating and fatigable proximal muscle weakness worse later in the day
- Ocular (eg, diplopia, ptosis)
- Bulbar (eg, dysphagia, dysarthria)
- Respiratory muscles
21
Q
List 4 general causes of myasthenia gravis exacerbations.
A
- Medications
- Pregnancy/childbirth
- Surgery (especially thymectomy)
- Infection
22
Q
List 5 classes of medications that can cause myasthenia gravis exacerbations.
A
- ABX (FQs, AGs)
- Anesthetics (neuromuscular blocking agents)
- Cardiac medications (beta blockers, procainamide)
- Other (mag sulfate, pencillamine)
- Tapering immunosuppressive medications
23
Q
What causes MG?
A
Autoantibody-mediated degradation of ACh receptors at the NMJ
24
Q
How does the ice pack test support the diagnosis of MG?
A
Ice pack applied over the eyelids for several minutes leads to improved ptosis; cold temperature improves muscle strength by inhibiting the breakdown of ACh at the NMJ, increasing availability
25
If the ice pack test is positive, what should be done next?
Confirmatory testing with ACh receptor Ab (highly specific)
26
Disruption of the oculosympathetic chain causes ___.
Horner syndrome
27
Presentation of Horner syndrome?
Ipsilateral ptosis, miosis, anhidrosis
28
What causes Lambert-Eaton myasthenic syndrome?
Autoantibodies directed against presynaptic calcium channels in the NMJ, leading to impaired ACh release
29
Presentation of Lambert-Eaton myasthenic syndrome?
Slowly progressive proximal muscle weakness and depressed deep tendon reflexes
30
Presentation of oculomotor nerve palsy?
Mydriasis, ptosis, down-and-out deviation of the eye
31
Causes of oculomotor nerve palsy?
Nerve compression (due to posterior communicating artery aneurysm or an uncal herniation)
Microvascular nerve ischemia (due to DM)
32
Cause of Guillain-Barre syndrome?
Immune-mediated demylinating polyneuropathy
Preceding GI (Campylorbacter) or respiratory infection
33
Presentation of GBS?
```
Parasthesia, neuropathic pain
Symmetric, ascending weakness
Decreased/absent DTRs (areflexia)
Autonomic dysfunction
Respiratory compromise
```
34
Dx GBS?
Clinical
Supportive findings:
-CSF: increased protein, normal leukocytes
-Abnormal EMG and nerve conduction
35
Management of GBS?
Monitor autonomic and respiratory function
| IVIG or plasmaphresis
36
Once Guillan Barre Syndrome is suspected in a hemodynamically stable patient, what is the next step in management?
Assess pulmonary function with spirometry
-FVC and negative inspiratory force monitor respiratory muscle strength; serial testing should be performed given the potential for rapid progression
37
What finding on PFTs indicates impending respiratory failure warranting endotracheal intubation? What are other indications for elective or emergency intubation?
Decline in FVC to 20 or less mL/kg; respiratory distress, severe dysautonomia, widened pulse pressure
38
What is the most common neoplasm to metastasize to the brain? List the next 4 most common.
Lung > Breast > Unknown primary > Melanoma > Colon
39
Presentation of brain mets on MRI?
Multiple, well-circumscribed lesions with vasogenic edema at the grey and white matter junction
40
List the 3 cancers that cause primarily solitary brain mets.
Breast
Colon
Renal cell carcinoma
41
List the 2 cancers that cause multiple brain mets.
Lung cancer
| Malignant melanoma
42
List 5 cancers that rarely cause brain mets.
```
Prostate
Esophageal
Oropharyngeal
HCC
Non-melanoma skin cancers
```
43
Lacunar infarctions are most typically seen in patients with ___.
Systemic hypertension
44
List the 4 benign sellar masses.
Pituitary adenoma (most common)
Craniopharyngioma
Meningioma
Ptiucytoma (low-grade glioma)
(May also be malignant - primary or metastatic)
45
Craniopharyngiomas are benign tumors arising from ___ and most commonly occur in what age group?
Rathke's pouch; children. However, nearly 50% occur in those age >20, especially between 55-65
46
2 types of cerebellopontine angle tumors?
Acoustic neuromas; meningiomas
47
Symptoms of cerebellopontine angle tumors?
Headache, hearing loss, vertigo, tinnitus, balance problems; do not usually cause visual disturbances, as they are below the optic pathways
48
Presentation - tunnel vision
Open-angle gluacoma
49
Presentation - acute to subacute painful vision loss with abnormal pupillary response to light in the affected eye
Optic neuritis
50
Presentation - headache, transient visual symptoms, pulsatile tinnitus; papilledema, visual field loss, CN 6 palsy
Pseudotumor cerebri
51
Features suggestive of psychogenic non-epileptic seizure (PNES)?
Forced eye closure, side-to-side head or body movements, memory recall of the event, lack of post-ictal confusion
52
Neurofibromatosis type 1 (NF1) is an autosomal ___ neurocutaneous disorder associated with what findings?
Dominant; cafe-au-lait macules, axillary and inguinal freckling, increased risk of seizures, learning disabilities, optic pathway gliomas, Lisch nodules, neurofibromas, pseudoarthrosis, scoliosis
53
List the 3 major types of headaches.
1. Migraine
2. Cluster
3. Tension
54
Compare the sex predilection among the three major types of headaches.
1. Migraine - F>M
2. Cluster - M>F
3. Tension - F>M
55
Compare the presence of family history among the three major types of headaches.
1. Migraine - often present
2. Cluster - no
3. Tension - no
56
Compare the onset among the three major types of headaches.
1. Migraine - variable
2. Cluster - during sleep
3. Tension - under stress
57
Compare the location of the three major types of headaches.
1. Migraine - often unilateral
2. Cluster - behind one eye
3. Tension - band-like pattern around the head (bilateral)
58
Compare the character of the three major types of headaches.
1. Migraine - pulsatile and throbbing
2. Cluster - excruciating, sharp and steady
3. Dull, tight, and persistent
59
Compare the duration of the three major types of headaches.
1. Migraine - 4-72 hours
2. Cluster - 15-90 minutes
3. Tension - 30 minutes to 7 days
60
Compare the associated symptoms of the three major types of headaches.
1. Migraine - auras, photophobia and phonophobia, and nausea
2. Cluster - sweating, facial flushing, nasal congestion, lacrimation, and pupillary changes
3. Tension - muscle tenderness in the head, neck, or shoulders
61
How should tension-type headaches be managed (intermittent vs. more frequent)?
If intermittent (no more than 1 day/month), can use analgesics +/- caffeine without concern for developing medication overuse headache
If more frequent, longer, or disabling, consider prophylactic medication (eg, amitriptyline) as well as CBT for stress-reduction
62
Presentation - progressive morning headache associated with frequent N/V, +/- seizure or neurological deficits
Brain tumors
63
Presentation - unilateral recurrent periorbital pain that resolves and recurs with associated ipsilateral miosis and ptosis
Cluster headaches
64
Presentation - patients >50, new-onset headaches localized to the temples, may be associated with fever, weight loss, vision changes, and jaw claudication
Giant cell arteritis
65
DDx - neuromuscular weakness - general locations of lesion?
1. UMNs
2. Anterior horn cells
3. Peripheral nerves
4. NMJ
5. Muscle fibers
66
DDx - neuromuscular weakness due to an UMN lesion?
1. Leukodystrophies
2. Vasculitis
3. Brain mass
4. Vitamin B12 deficiency
67
DDx - neuromuscular weakness due to anterior horn cell lesions?
1. Spinal muscular atrophy (flaccid paralysis in infancy)
2. ALS
3. Paraneoplastic syndromes
4. Poliomyelitis
68
DDx - neuromuscular weakness due to peripheral nerve lesions?
1. Hereditary primary motor sensory neuropathy
2. GBS
3. Diabetic neuropathy
4. Amyloid neuropathy (myeloma)
5. Lead poisoning
69
DDx - neuromuscular weakness due to NMJ lesion?
1. MG (weakness worse with use, better with rest)
2. Lambert-Eaton (progressive proximal muscle weakness)
3. Organophosphate poisoning (weakness + multisystem cholinergic symptoms)
4. Botulism (descending paralysis)
70
DDx - neuromuscular weakness due to muscle fiber lesion?
1. Muscular dystrophies
2. Polymyositis and dermatomyositis
3. Hypothyroidism
4. Corticosteroids
5. HIV myopathy
71
What is the pathogenesis of GBS?
Immune-mediated polyneuropathy caused by demyelination of peripheral nerve fibers; most patients have a preceding respiratory or GI infection that triggers an immune response. Antibodies are then redirected toward cross-reacting antigens on myelin or axons (molecular mimicry)
72
Presentation of GBS?
Ascending weakness, often accompanied by paresthesias and neuropathic pain; most severe symptoms include flaccid paralysis with diminished or absent DTRs and respiratory failure. Accompanying autonomic symptoms (BP/HR instability, ileus, etc.) often parallel the severity of motor deficits
73
Rx GBS?
IVIG or plasmapheresis
74
What is autonomic dysreflexia?
Complication of spinal cord injury above T6; in an intact spinal cord, sympathetic activity is modulated by higher-level neurons. SCI results in loss of modulatory activity below the lesion. Noxious stimuli (eg, urinary retention, constipation, pressure ulcers) can cause an unregulated sympathetic response, leading to vasoconstriction and severe hypertension. Above the lesion, a compensatory parasympathetic response causes diaphoresis, flushing, bradycardia, and nasal congestion. Vasodilation occurs but cannot overcome the sympathetic drive to normalize systemic pressure.
75
Complications of autonomic dysreflexia?
Intracranial hemorrhage or progressive bradycardia with cardiac arrest
76
Management of autonomic dysreflexia?
Close monitoring of blood pressure; place the patient in an upright position to encourage orthostatic BP reduction
Search for precipitating events (urinary retention, fecal impaction, pressure sores)
Remove tight-fitting close
Short-duration antihypertensives may be needed
77
What is carotid sinus hypersensitivity and how does it typically present?
Significant drop in heart rate (pauses) and blood pressure (>50 mm Hg) following carotid massage; lightheadedness or syncope after carotid manipulation in older patients with atherosclerotic disease
78
Presentation - older individual, back/shoulder pain following physical activity, loss of shoulder abduction strength, reduced sensation in the left lateral forearm
C5-C6 nerve root impingement from cervical radiculopathy; may be due to acute cervical disc herniation or cervical spondylosis
79
What are the two clinical syndromes associated with cervical spondylosis?
1. Cervical radiculopathy
| 2. Compressive cervical myelopathy
80
What causes cervical radiculopatyh and how does it present?
Degeneration and osteophyte formation in the zygapophyseal and uncovertebral joints -> intervertebral foramen narrowing and compressive nerve root symptoms (progressive neck, shoulder, and/or arm pain plus weakness in a myotome and sensory loss in a dermatome)
81
What causes compressive cervical myelopathy and how does it present?
Degeneration and thickening of the lateral vertebral bodies and posterior longitudinal ligament lead to spinal canal narrowing and subsequent spinal cord compression; neck pain, LMN signs in the upper extremities, UMN signs in the lower extremities, and bowel/bladder dysfunction
82
First test of choice in the setting of cervical radiculopathy?
MRI of cervical spine
83
Presentation of diabetic neuropathy?
Alterations in sensation, including loss of proprioception; motor findings may be a late manifestation in the most severe cases
84
Why can uncontrolled infection of the skin, sinuses, and orbit spread to the cavernous sinus?
Because the facial/ophthalmic venous system is valveless
85
Presentation of cavernous sinus thrombosis?
Intracranial HTN -> headache, vomiting, papilledema; followed by low-grade and periorbital edema several days later (due to impaired venous flow); CN lesions may include binocular palsies, periorbital edema, hypoesthesia, or hyperesthesia in V1/V2 distribution (unilateral -> bilateral)
86
What are the structures surrounding the cavernous sinus?
Optic chiasm
Internal carotid artery with PCA branch
Pituitary gland
CN III, IV, V (1 and 2), VI
87
Imaging modality of choice to diagnose cavernous sinus thrombosis?
MRI with MR venography
88
Rx cavernous sinus thrombosis?
Broad-spectrum IV ABX, prevention or reversal of cerebral herniation
89
___ should be considered in any patient with fever, headache, and focal findings on neurologic examination.
Brain abscess
90
Inheritance pattern of neurofibromatosis type 1?
Autosomal dominant
91
Clinical features of NF1?
Multipel cafe-au-lait macules, axillary and inguinal freckling, Lisch nodules (iris hamartomas) neurofibromas, learning disability, scoliosis, pseudoarthritis
Increased risk of neurological disorders and intracranial neoplasms (optic pathway glioma)
92
What type of tumor typically develops in patients with neurofibromatosis type 2?
Bilateral acoustic neuromas (aka vestibular schwannomas)
93
Clinical features of tuberous sclerosis?
Benign tumors in multiple organs -> ash leaf spots, angiofibroms, shagreen patches, intracardiac rhabdomyomas
94
Clinical features of fragile X syndrome?
Intellectual disability, large ears, long/narrow face, macroorchidism, seizures
95
Clinical features of Sturge-Weber syndrome?
Port-wine stain on the face
Ocular disease (visual deficits, glaucoma, etc.)
Leptomeningeal capillary-venous malformation (may cause seizures)
96
Presentation - areflexic weakness in the upper extremities and dissociated sensory loss in a cape distribution
Syringomyelia
97
What is syringomyelia and what is the most common cause?
Fluid-filled cavity within the cervical and thoracic spinal cord that is most commonly associated with Arnold Chiari malformation type 1
98
Describe the pathogenesis of syringomyelia.
Lesion disturbs the decussating STTs in the anterior commissure; vibration/proprioception is preserved as the dorsal spinal column is not usually affected (dissociated sensory loss). As the cavity enlarges, there can be interruption of the anterior horn gray matter, resulting in LMN signs in the upper limbs (areflexic weakness)
99
Presentation - sudden flaccid paralysis, loss of pain and temperature below the lesion; intact position, vibration, touch
Anterior cord syndrome
100
Presentation - sub-acute onset of flaccid paralysis and loss of all types of sensation below the level of the lesion
Segmental demyelination/inflammation of the spinal cord (transverse myelitis)
