Neuro HARC 2

Question 1

What is ALS?

Answer 1

Amyotrophic lateral sclerosis (ALS) is a group of rare neurological diseases that mainly involve the nerve cells (neurons) responsible for controlling voluntary muscle movement. Voluntary muscles produce movements like chewing, walking, and talking. The disease is progressive, meaning the symptoms get worse over time

Question 2

What tracts are involved in ALS?

Answer 2

It presents as a combination of disease of the lateral corticospinal tracts, corticobulbar tracts, and anterior horn cells

Question 3

Individuals who suffer from ALS often start with weakness in their ___or difficulty with ____and _____

This will progress until they lose the ability to use their limbs, ____, ______, and _____

Answer 3

Individuals who suffer from ALS often start with weakness in their limbs or difficulty with swallowing and phonation.

This will progress until they lose the ability to use their limbs, speak, swallow, and breathe

Question 4

ALS

What are the upper motor neurone signs and why is this the presentation?

Answer 4

Spastic paralysis, no wasting or fasciculations, hyperreflexia, clonus and Babinski reflex present. Loss of voluntary motor control but muscles still receive innervation from extrapyramidal system

Question 5

ALS

What are the lower motor neurone signs and why is this the presentation?

Answer 5

Flaccid paralysis, wasting and fasciculations, areflexia, no clonus and absent Babinski reflex. Loss of both pyramidal and extrapyramidal systems.

Question 6

ALS is described as an idiopathic, what does this mean?

Answer 6

Used to describe a condition or disease which has arisen spontaneously or is of unknown cause

Question 7

Which two cranial nerves do not arise from the brain stem and how are they traditionally classified?

Answer 7

CN 1 and 2; atypical.

Question 8

Which cranial nerves can be found passing through the jugular foramen?

Answer 8

CN IX, X and X1

Question 9

Which part of the brainstem does the trochlear nerve arise from?

Answer 9

Midbrain

Question 10

• Midbrain lesions cause disturbances of ___ ________
• Pontine lesions cause disturbances of _________ _______
• Medullary lesions cause disturbances of ______ and _______

Answer 10

• Midbrain lesions cause disturbances of eye movements
• Pontine lesions cause disturbances of mandibular movement
• Medullary lesions cause disturbances of phonation and swallowing

Question 11

Whilst midbrain lesions typically cause disturbances of eye movements, where else could a lesion cause eye movement disturbance? What cranial nerve would be involved?

Answer 11

Pontine lesion and Abducens nerve – responsible for lateral rectus innervation resulting in issues with abduction (lateral eye movement).

Question 12

Which other cranial nerve passes through the internal acoustic meatus alongside the facial nerve?

Answer 12

Vestibulocochlear nerve (CN VIII)

Question 13

What is the function of the parotid gland and which cranial nerve innervates it?

Answer 13

Main salivary production site and the glossopharyngeal nerve (CN IX)

Question 14

Answer 14

Question 15

What symptoms would you expect an individual to present with if they had compression of the facial nerve in the facial canal?

Answer 15

: Unilateral facial paralysis, Hyperacusis (stapedius muscle compromised), loss of anterior tongue taste sensation and decreased salivation.

Question 16

What is bell’s palsy?

Answer 16

Bell’s palsy is a form of facial paralysis involving the facial nerve which presents as an inability to control the facial muscles on one side of the face

Question 17

Risk factors for Bell’s Palsy?

Answer 17

Risk factors for Bell’s Palsy include diabetes and recent infections, there are also links to the herpes virus.

Question 18

If facial paralysis cannot be identified as relating to a brain tumour, stroke or myasthenia gravis for example, then it is defined as ____ _____

Answer 18

If facial paralysis cannot be identified as relating to a brain tumour, stroke or myasthenia gravis for example, then it is defined as Bell’s palsy.

Question 19

What is the largest cranial nerve

Answer 19

Trigeminal

Question 20

Where does trigeminal nerve original from?

Answer 20

pons from the merging of sensory and motor nuclei into their own distinct roots.

Question 21

three divisions of the trigeminal nerve:

Answer 21

: ophthalmic (V1), maxillary (V2) and mandibular (V3).

Question 22

u, name the 3 divisions of the Trigeminal nerve – how do they exit the skull and what does each division supply?

Answer 22

Ophthalmic (Superior Orbital Fissure),

Maxillary (Foramen Rotundum)

Mandibular (Foramen Ovale)

Question 23

What is Trigeminal neuralgia

Answer 23

er neuropathic disorder with an unknown cause that can cause intense facial pain

Question 24

Is trigeminal neuralgia affecting the sensory or motor component of the trigeminal nerve? Explain your answer

Answer 24

Sensory component – This carries the sensations of pressure, temperature, and pain. Confusion arises with this condition due to the trigeminal neuralgia causing sudden contraction of facial musculature, the nerve acting here is CN VII and is not due to damage but is a standard reflex action to pain sensation around the face.

Question 25

How would you test the motor and sensory components of the trigeminal nerve separately?

Answer 25

Sensory component: Ask the patient to close their eyes and touch their face using cotton wool wisps to test sensory competence. If sensation felt in the three areas of sensory innervation, then sensory component is intact.

Motor component: Ask the patient to clench their teeth and palpate above and below zygomatic arch to test for temporalis and masseter function, respectively. Following this ask the patient to move their mandible from side to side to test pterygoid function

Question 26

How would a lesion of the facial nerve affect the corneal reflex?

Answer 26

The eye would be unable to blink as the orbicularis oculi muscle responsible for this movement would have lost its innervation therefore leaving the eye open to damage.

Question 27

Can you think of any way in which human beings manually override their corneal reflex?

Answer 27

Putting in contact lenses dampens the reflex which can leave the eyes prone to drying out in windy conditions

Question 28

What is Pupillary light reflex?

Answer 28

This reflex is where a light is shone into one eye causes both pupils to contract. This reflex is a crude test of brain stem function because it does not involve cortical activity and can be performed on an unconscious patient

Question 29

Which structures are involved in the pupillary light reflex?

Answer 29

Optic nerve, optic chiasma, optic tract, midbrain and oculomotor nerve (parasympathetic component), ciliary ganglion and iris muscle

Question 30

pupillary light reflex is known as a commissural reflex, what does this mean?

Answer 30

It communicates across both hemispheres of the brain and hence the reason both pupils contract

Question 31

What is Accommodation reflex?

Answer 31

This reflex is when focusing on a near object and then looking away results in changes in the size of the pupil (near: constricted and far: dilated).

Question 32

Which extraocular muscle is particularly important in the convergence phase of the accommodation reflex?

Answer 32

The medial rectus as it draws the eyes medially towards each other which makes it easier to see objects that are closer to you.

Question 33

What is Argyll Robertson pupil?

Answer 33

In AR pupil, which is rare in the developed world, there is no reaction to the light, and it is associated with diabetic neuropathies and neurosyphilis

Question 34

What is saccades?

Answer 34

Saccades in the eyes are rapid and simultaneous movement of the eyes from a fixed position to another fixed position in the same plane of movement

Question 35

Which part of the midbrain controls saccadic eye movements?

Answer 35

The Superior colliculi

Question 36

What is Smooth pursuit

Answer 36

This is a type of a gaze shifting that occurs when you are tracking a moving object, essentially following a movement

Question 37

What is Nystagmus

Answer 37

When rotating eyes about an axis in one direction, the eyes will rotate in the opposite direction to sustain distal images and help in conveying angular momentum to the semicircular canals of the vestibular apparatus to maintain balance.

Question 38

There are 2 types of nystagmus. What are they?

Answer 38

Pathologic nystagmus

Physiological nystagmus

Question 39

Which cranial nerves will be involved in producing saccades and nystagmus?

Answer 39

Cranial nerves associated with eye movements so CN III, IV and VI as well as VIII which takes positional information from the inner ear to the brain

Question 40

What is Pathologic nystagmus

Answer 40

bnormal response induced by damaged to vestibular apparatus, vertigo, lesions of midbrain/cerebellum.

o Central nystagmus – lesions not associated with vestibular apparatus

o Peripheral nystagmus – lesions associated with vestibular apparatus

Question 41

What is Physiological nystagmus

Answer 41

normal reflex action when the vision is subjected to rotational movements of the head (post-rotary nystagmus) or watching an object being continuously rotated (optokinetic nystagmus).