Neurology

Question 1

What is ataxia?

Answer 1

impaired coordination of voluntary movements, usually caused in children by cerebellar dysfunction or, less frequently, vestibular or proprioceptive afferent dysfunction.

Question 2

What are the 3 most common causes of acute ataxia?

Answer 2

1) Acute postinfectious cerebellar ataxia
2) Drug ingestion
3) Guillain–Barré syndrome

Question 3

How does gait ataxia present?

Answer 3

wide-based gait with inability to walk without support, especially on tandem gait

Question 4

What kind of injury causes limb ataxia?

Answer 4

Lesions in the cerebellar hemispheres or peduncles are associated with ipsilateral limb ataxia. Appendicular ataxia, caused by lesions in the lateral hemispheres of the cerebellum that leads to ataxic movements in the extremities

Question 5

How can limb ataxia be elicited on physical exam?

Answer 5

rapid alternating movement, finger tapping, and finger-to-nose tests

Question 6

Where is an injury that elicits a positive rhomberg?

Answer 6

Cerebellar afférent or efferent pathways outside the cerebellum

Question 7

Describe acute postinfectious cerebellar ataxia

Answer 7

usually observed in toddlers
prodrome of nonspecific viral illness followed after days or up to 2 to 3 weeks by ataxia
clinical course is usually benign, with full return to baseline within 8 months in 70% of children

Question 8

Describe ADEM

Answer 8

immune-mediated demyelinating condition
often occurs postinfectiously
predominantly in school-age children. usually associated with focal neurologic deficits, often including ataxia and various degrees of encephalopathy, but also cranial nerve abnormalities, pyramidal signs, and speech impairment.
Maximal severity is usually observed within 2 to 5 days from onset of symptoms.
MRI usually shows reversible, ill-defined white matter lesions with frequent involvement of brain (including cortical and subcortical structures such as thalami and basal ganglia) and spinal cord. CSF often shows lymphocytic pleocytosis and increased protein.

Question 9

When is the peak incidence of Guillain barre?

Answer 9

5-6 years

Question 10

How does the miller-fisher variant of GBS usually present?

Answer 10

more severe and more rapid onset than GBS, and classically presents with ataxia, areflexia, and ophthalmoplegia.

Question 11

How does posterior circulation ischemic stroke present? (Due to vertebral artery dissection)

Answer 11

ataxia, headache, vomiting, cranial nerve deficits, and hemiparesis

Question 12

When does varicella encephalitis appear?

Answer 12

2-9 days after onset of rash

Question 13

What part of the brain does herpes encephalitis affect most?

Answer 13

Temporal

Question 14

How long before anoxia causes permanent brain damage?

Answer 14

4-5 mins

Question 15

What is hypertensive encephalopathy?

Answer 15

headache, nausea, vomiting, visual disturbance, ALOC, or coma in the presence of a blood pressure greater than the 95th percentile for age and gender

Question 16

compression of what cranial nerve is responsible for fixed/dilated pupils in uncal herniation?

Answer 16

3

Question 17

What cranial nerves are tested in the dolls eye maneuver?

Answer 17

3, 4, 6 + vestibular branch of 8

Question 18

What is a positive dolls eye reflex?

Answer 18

patient moves their eyes opposite of the rotation of their head, such that their eyes stay looking forward (like a doll’s eyes)

Question 19

Treatment for acute dystonia secondary to meds eg. Maxeran

Answer 19

Benadryl 1mg/kg
Or
Benztropine 1-2mg per dose IM

Continue x 24-48hrs

Question 20

Dose of 3%NS for increased ICP

Answer 20

Bolus 5ml/kg
Infuse 0.1-1ml/kg/hr

Question 21

What test is associated with each of the following tracts?
Spinothalamic
Corticospinal
Dorsal column

Answer 21

Spinothalamic - pain, temperature + touch
(pin-prick)
Corticospinal - voluntary motor control
Dorsal column - proprioception, touch, position, vibration (toe up/down)

Question 22

What is Brown-Sequard syndrome?

Answer 22

hemisection of the spinal cord involving contralateral loss of pain and temperature sensation with ipsilateral motor findings below the lesion

Question 23

What is central cord syndrome?

Answer 23

Injury most severe in the centre of the spinal cord - motor strength more severely depressed in arms than legs

Question 24

What is anterior cord syndrome

Answer 24

loss of neurologic function if areas supplied by anterior spinal artery - motor function lost below level of lesion but touch + proprioception preserved

Question 25

What is posterior cord syndrome?

Answer 25

Loss of proprioception, deep pressure, pain and vibration with preservation of motor and temperature sensation

Question 26

Most common pathogens for VP shunt infection before and after 6 months from insertion

Answer 26

Before - gram positive
- staph aureus
- cons
- other strep species

After - gram negative
- ecoli
- enterococcus
- h. influenzae