Neurology Flashcards
At what nerves does the parasympathetic nervous system arise?
Cranial nerves 3, 7, 9 and 10
Sacral spinal nerves 2, 3, and 4
Does micturition have sympathetic or parasympathetic innervation?
Parasympathetic
What is the pathological cause of Alzheimer’s disease?
Cortical plaques due to deposition of type A-Beta-amyloid protein and intraneuronal neurofibrillary tangles caused by abnormal aggregation of the tau protein
Lesions in which lobe may cause anosmia?
Frontal lobe
What is anosmia?
The loss of the ability to discern smells
What are the symptoms of damage to the frontal lobe?
- Expressive (Broca’s) aphasia
- Disinhibition
- Perseveration
- Anosmia
- Inability to generate a list
What is disinhibition?
The inability to withhold a prepotent response or suppress an inappropriate or unwanted behaviour. It can also refer to the production of socially inappropriate comments and/or actions.
What is perseveration?
The repetition of a particular response regardless of the absence or cessation of a stimulus
Damage to which lobe causes Broca’s aphasia?
Frontal lobe
Which structures pass through the jugular foramen?
Cranial nerves IX, X and XI
Internal jugular vein
What is Vernet syndrome?
Jugular foramen syndrome which is a group of cranial nerve palsies as a result of compression from a jugular foramen lesion.
What part of the hypothalamus controls satiety?
Ventromedial nucleus
What is hyperphagia?
Abnormal sensation of hunger/desire to eat leading to overeating
What function is carried by the corticospinal tract?
Motor
Where does the corticospinal tract cross the midline?
At the brainstem/medulla
Anatomically, where does the corticospinal tract run in the spinal cord?
Posterolaterally
What function(s) are carried by the spinothalamic tract?
Pain and temperature
Where does the spinothalamic tract cross the midline?
Immediately upon entering the spinal cord
Anatomically, where does the spinothalamic tract run in the spinal cord?
Anterolaterally
What function(s) are carried by the dorsal columns?
Vibration and proprioception
Where do the dorsal columns cross the midline?
At the brainstem/medulla
Anatomically, where do the dorsal columns run in the spinal cord?
Posteriorly
What spinal levels innervate the biceps?
C5/6
What spinal levels innervate the triceps?
C6, 7, 8
What spinal levels innervate the knees?
L3/4
What spinal levels innervate the ankles?
S1/2
What are the six stages of the muscle power scale?
5 = normal power 4 = movement possible against gravity and some resistance 3 = movement possible against gravity 2 = movement possible when gravity excluded 1 = flicker of contraction possible 0 = complete paralysis
What is an AP view of the cervical spine?
Allows you to see the vertebrae
What is a lateral XR of a cervical spine used for?
To check for misalignment
What is an open mouth peg XR used for?
To check the odontoid process (it should be equidistant between the lateral masses of the atlas)
What are the features of an essential tremor?
- Postural tremor that gets worse if the arms are outstretched
- Improved by alcohol and rest
- Most common cause of titubation (head tremor)
- Absence of other neurological signs or symptoms
- Mainly symmetrical
What is the management of essential tremor?
1st line = propranolol or primidone
What is neuropraxia?
A transient (temporary) complete block of neuronal transmission that completely resolves spontaneously.
What causes neuropraxia?
- Blunt injuries
- Compression
- Stretching of nerves following dislocations and fractures
What are the features of neuropraxia?
- The nerve remains intact but electrical conductivity is affected
- Myelin sheath integrity is preserved
- No Wallerian degeneration
- Autonomic function preserved
- Recovers spontaneously
What is Kluver-Bucy syndrome?
A syndrome resulting from bilateral lesions on the medial temporal lobe (including the amygdala)
What are the features of Kluver-Bucy syndrome?
- Hyperorality (putting inappropriate objects in your mouth)
- Hypersexuality
- Hyperphagia
- Visual agnosia (inability to recognise objects and people)
- Docility
What do lesions/damage to the frontal lobe cause?
- Expressive (Broca’s) aphasia
- Disinhibition
- Perseveration
- Anosmia
- Inability to generate a list
Damage to what location causes expressive (Broca’s) aphasia?
Posterior aspect of the frontal lobe, specifically the inferior frontal gyrus
What is a lacunar stroke?
The most common type of ischaemic stroke where small penetrating arteries that supply the deep brain structures are occluded. There is a strong association with hypertension.
What is the presentation of a lacunar stroke?
- Isolated hemiparesis
- Hemisensory loss
- Hemiparesis with limb ataxia
What are the commonly affected areas of the brain in a lacunar stroke?
- Basal ganglia
- Thalamus
- Internal capsule
What is autonomic dysreflexia?
A condition triggered by faecal impaction or urinary retention resulting in sympathetic stimulations and hyperactivity seen as uncontrolled hypertension and bradycardia above the level of a spinal cord lesion
What patients are at risk of autonomic dysreflexia?
- Spinal cord injuries with lesions at or above T6
- Guillain-Barré syndrome
What medication is used for long-term prophylaxis of cluster headaches?
Verapamil
What is the most appropriate diagnostic investigation for bitemporal hemianopia?
MR of pituitary fossa
What is acute dystonic reaction?
Involuntary contractions of muscles of the extremities, face, neck, abdomen, pelvis, or larynx in either sustained or intermittent patterns that lead to abnormal movements or postures
What is the cause of acute dystonic reaction?
Dopaminergic-cholinergic imbalance in the basal ganglia caused by dopamine-receptor blocking agents
What medications commonly cause acute dystonic reaction?
Antipsychotics (particularly typical/1st gen) and antiemetics (particularly metoclopramide and prochlorperazine)
What is Holmes-Adie syndrome?
A rare condition that causes dilated pupils, slow pupil reaction to light as well as absent/reduced tendon reflexes
When the eye is deviated ‘down and out’ what nerve palsy does this indicate?
Occulomotor
What pathological process occurs in motor neuron disease?
Loss of large cholinergic neurones from the spinal cord
What is essential tremor?
Progressive, symmetrical, involuntary tremor of the hands, forearms, voice and head that is usually absent at rent and present during posture and intentional movements
What substances reduces essential tremor?
- Alcohol
- Benzos
- Barbiturates
- Gabapentin
What are the characteristics of Parkinsonian tremor?
- Resting
- Unilateral
When do enhanced physiological tremors appear?
In situations of stress, anxiety or excessive caffeine use i.e. in the absence of neurological disease
What is cervical radiculopathy?
When a nerve in the neck is compressed or irritated where it branches away from the spinal cord
What are the signs and symptoms of cervical radiculopathy?
- Burning/sharp pain in the neck travelling down the arm along the nerve path
- Tingling/pins and needles in fingers and hand
- Weakness in muscles of arm, shoulder or hand
- Exacerbated by neck movements
What are the key diagnostic factors for motor neuron disease?
- Fasciculations
- Mixture of upper and lower motor neuron symptoms
- Wasting of small hand muscles
- No sensory loss
What is myasthenia gravis?
A chronic autoimmune disorder of the post-synaptic membrane at the neuromuscular junction in skeletal muscle
What are the characteristic signs and symptoms of myasthenia gravis?
- Muscle weakness that increases with exercise and improves on rest
- Drooping eyelids
- Double vision
- Oropharyngeal/appendicular weakness
- Dyspnoea
What is a myasthenic crisis?
Exacerbation of symptoms leading mechanical ventilation being required
What is the first-line treatment for myasthenia gravis?
Pyridostigmine (acetylcholinesterase inhibitor)
