Neuro CC Questions Flashcards
How does a migraine typically present?
- A moderately severe, unilateral, throbbing headache
- Often associated with nausea, vomiting, and photophobia and
- May be preceded by (< an hour) an aura — transient neurological symptoms - visual, sensory, or motor.
Subarachnoid haemorrhage, carotid or vertebral dissection features
- Sudden abrupt (may be precipitated by cough, coitus, exertion).
- Very severe
- Particularly associated with collapse, confusion, neurological signs, vomiting, or neck stiffness.
Subdural haematoma features
- Hours, days, or weeks after head trauma (particularly if LOC).
- Gradually worse
- Nausea, vomiting, confusion, decreased level of consciousness.
- An extradural haematoma has similar symptoms with much more rapid progression over hours. Life threatening.
Meningitis, encephalitis features
- Fairly rapid with systemic illness.
- Progressively worse, severe, steady/throbbing.
- Fever, nausea, vomiting, rash, drowsiness, neck stiffness.
Increased intracranial pressure features (Possible space occupying lesion or benign intracranial hypertension)
- Gradual.
- Worse on morning waking and improving
during the day. - Nausea, vomiting, can be worse with coughing or sudden head movements.
Temporal arteritis features
- Gradual or rapid
- Adults >50yrs
- Fever, tender temporal arteries and scalp, myalgia, weight loss, jaw claudication, raised ESR, sudden visual loss.
Benign intracranial hypertension features
- Gradual
- Young patient with progressive headache
- Nausea, vomiting, papilloedema. Tetracyclines (Rx for acne), obesity.
What triad of symptoms suggests Meniere’s Disease?
- Episodic vertigo
- Tinnitus
- Progressive sensineural deafness
What is the difference between dysphasia, dysarthria and dysphonia?
- Dysphasia – dominant higher centre disorder in the use of symbols for communication – language
- Dysarthria – difficulty with articulation
- Dysphonia – altered quality of the voice – result of vocal cord disease
Why do we ask the patient to fixate on a distant object when testing the light reflex?
This is to avoid the accommodation reflex (where the eyes pupils will usually constrict and the eyes converge) when focusing on a near object.
Why should pungent substances such as ammonia be avoided when testing the olfactory nerve (CN I)?
Pungent substances such as ammonia should not be used, first because they upset the patient and second because noxious stimuli of this sort are detected by sensory fibres of the fifth (trigeminal) nerve.
What is the normal pupillary response when assessing RAPD (relative afferent pupillary defect) and what is an abnormal response? What does this abnormal response indicate?
Normally you would expect both the pupils to constrict to a similar degree when the torch is shone in either eye (the direct and consensual reflex) and dilate slightly during the “swing” phase when the torch is not shining directly in either eye.
If an eye has optic atrophy or reduced visual acuity from another cause, the affected pupil will dilate paradoxically after a short time when the torch is moved from the normal eye to the abnormal eye. This is called a relative afferent pupillary
defect (RAPD or the Marcus Gunn pupillary sign). It occurs because an eye with even mildly reduced acuity has reduced afferent impulses so that the light reflex is decreased. When the light is shone from the normal eye to the abnormal one the pupil dilates, as reflex pupillary constriction in the abnormal eye is so reduced that relaxation after the consensual response dominates.
The Clinical Practice Handbook 2019 also lists as possible causes:
- Optic Neuritis
- Ischaemic optic neuropathy
- Nerve compression by orbital tumour or at a sight pre- chiasma
- Asymmetric glaucoma.
What ocular muscles does CN III (Oculomotor) innervate and what would you expect to see clinically, if a patient had an CN III palsy?
- CN III innervates:
- Superior Rectus
- Inferior Rectus
- Medial Rectus
- Inferior Oblique
- CN III Palsy: Ptosis, Eye turned down and out, dilated non-reactive pupil, unreactive to accommodation, opposite pupil reacts normally
What ocular muscles does CN IV (Trochlear) innervate and what would you expect to see clinically, if a patient had an CN IV palsy?
- CN IV innervates the Superior Oblique.
- CN IV Palsy: Weakness of downward and outward gaze. The patient may walk around with his or her head tilted away from the lesion—that is, to the opposite shoulder (this allows the patient to maintain binocular vision)
What ocular muscles does CN VI (Abducens) innervate and what would you expect to see clinically if a patient had an CN VI palsy?
- CN VI innervates the lateral rectus.
- CN VI Palsy: Weakness of lateral gaze on the affected side (rarely bilateral).
Why is it best to test sensation of the trigeminal nerve on the forehead, maxilla and mandible approximately along an imaginary vertical line drawn through the eyes?
This strategy helps avoid a smaller innervated zone near the maxillary division and the angle of the mandible, which is innervated by the C2 cervical nerve root.
Can you describe how you would test the corneal reflex and which nerves are involved in the afferent and efferent component?
- Using a very fine twist of cotton wool, gently touch the surface of the cornea, while the patient is looking at a focal point across the room.
- You can rest your hand gently on the patient’s cheek to stabilise the approaching stimulus.
- Do not cross the line of sight, touch the sclera or the eyelashes.
- Both eyes should close after the cornea is touched.
- The afferent sensory signal is via CN V, the Trigeminal Nerve, and the efferent motor response is via CN VII, the Facial Nerve (orbicularis oculi muscle).
How do you test the Masseter (Jaw jerk) reflex? What is a normal response? What might an exaggerated response indicate?
- Ask the patient to relax their jaw, with their mouth partly open
- Place your finger on the anterior surface of the chin
- Gently strike your finger with a tendon hammer
- Normally, there is a slight closure of the mouth or no reaction at all. In an upper motor neurone lesion above the pons, the jaw jerk is greatly exaggerated. This is commonly seen in pseudobulbar palsy.
In Bell’s palsy (a lower motor neuron lesion - LMN) there is complete hemiplegia of the face whereas after a CVA (an upper motor neuron lesion - UMN) there is forehead sparing in the presence of facial paralysis. Why?
This is the result of the bicortical representation of the frontalis muscle within the motor homunculus, in the cerebral cortex, combined with bilateral descending innervation to CNVII’s motor nucleus. It is unknown why this exception exists.
Describe the Weber Test and explain possible results and their significance?
- Ring a 256Hz tuning fork and place its base on the patient’s forehead (in the midline)
- Ask the patient which direction the sound/vibration seems to be the loudest
- Make note of result – midline (normal), lateralised (left or right Weber)
- Nerve deafness causes the sound to be heard better in the normal ear. A patient withUpdated June 2019
- conduction deafness finds the sound louder in the abnormal ear.”
- Note that you can mimic the effect of conductive deafness by blocking off an ear with your finger and doing Weber on yourself – the sound will seem to lateralise to the side that you have blocked off. Give it a try in class. It might help you remember!
Describe Rinne’s test and explain possible results and their significance?
- Ring a 256Hz tuning fork and place its base on one mastoid process
- Ask the patient to report to you when they stop hearing the ringing sound
- Immediately turn the tuning fork to bring the end of the forks close to the external auditory meatus
- Ask the patient if they can hear anything
- If the patient can hear the ringing, Air Conduction (AC) in that ear must be greater than
- Bone
- Conduction (BC) – Make note of the result e.g. “AC>BC in Right Ear”
- Repeat on opposite side
- Normally the note is audible at the external meatus. If the patient has nerve deafness, the note is audible at the external meatus, as air and bone conduction are reduced equally, so that air conduction is better (as is normal). This is termed Rinné-positive. If there is a conduction (middle-ear) deafness, no note is audible at the external meatus. This is termed Rinné negative.
In the cranial nerve exam, if you noticed that the uvula was displaced, what nerve might be damaged? Would the uvula be drawn to the side of the damaged nerve or to the “normal” side?
Normally, the posterior edge of the soft palate—the velum —rises symmetrically. If the uvula is drawn to one side this indicates a unilateral tenth nerve palsy. Note that the uvula is drawn towards the normal side.
