eMRCS Head and Neck Flashcards
Which of the following nerves is responsible for the motor innervation of the sternocleidomastoid muscle?
Ansa cervicalis Accessory nerve Hypoglossal nerve Facial nerve Vagus nerve
Accessory nerve
The motor supply to the sternocleidomastoid is from the accessory nerve. The ansa cervicalis supplies sensory information from the muscle.
A 53 year old man is admitted to the vascular ward for a carotid endarterectomy. His CT head report confirms a left parietal lobe infarct. What type of visual field defect might be noted?
Right inferior quadranopia Right superior quadranopia Right homonymous hemianopia Left superior quadranopia Lower bitemporal hemianopia
Right inferior quadranopia
Superior quadranopia = temporal lesion
Inferior quadranopia = parietal lesion
A motorcyclist is injured in a RTA and is not wearing a helmet. He suffers a severe closed head injury and develops raised intracranial pressure. The first cranial nerve to be affected by this process is likely to be:
Oculomotor Hypoglossal Motor branch of trigeminal Sensory branch of trigeminal Abducens
Abducens nerve
The abducens nerve (CN VI) has a long intracranial course and is thus susceptible to raised ICP.
It also passes over the petrous temporal bone and 6th nerve palsies are also seen in mastoiditis.
Which cranial nerve supplies the motor fibres of styloglossus?
Facial Trigeminal Vagus Hypoglossal Glossopharyngeal
Hypoglossal
The hypoglossal nerve supplies motor innervation to all extrinsic and intrinsic muscles of the tongue.
The only possible exception to this is palatoglossus, which is innervated by the vagus.
Which of these muscles is innervated by the cervical branch of the facial nerve?
Masseter Sternocleidomastoid Platysma Geniohyoid Sternothyroid
Platysma
A 63 year old man is admitted with severe headache, nausea and recent epileptic fit. Fundoscopy shows papilloedema. He is also noted to have diplopia. Which of the cranial nerves listed accounts for the latter?
Abducens Optic Oculomotor Facial Trigeminal
Abducens nere
The long intracranial course of this nerve makes it susceptible to damage early in the course of raised ICP.
A 60 year old female attends the preoperative hernia clinic. She reports some visual difficulty. On examination she is noted to have a homonymous hemianopia. Where is the lesion most likely to be?
Frontal lobe Pituitary gland Parietal lobe Optic chiasm Optic tract
Optic tract
Lesions BEFORE optic chiasm:
Monocular vision loss = optic nerve
Bitemporal hemianopia = optic chiasm
Lesions AFTER optic chiasm:
Homonymous hemianopia = optic tract
Upper quadranopia = temporal lobe
Lower quadranopia = parietal lobe
A 53 year old man presents with unilateral hyperacousia. Which of the following nerves is least likely to be functioning normally?
Vestibulocochlear Glossopharyngeal Facial Trochlear Vagus
Facial nerve
Damage to the nerve in the bony canal may result in impaired innervation to stapedius and therefore sounds are no longer dampened.
Another cause of hyperacusis is increased activity in the tensor tympani muscle, this is innervated by the trigeminal nerve.
What type of visual field defect is most likely to be noted in a patient with a craniopharyngioma?
Lower bitemporal hemianopia Upper bitemporal hemianopia Right superior quadranopia Right homonymous hemianopia Left homonymous hemianopia
Lower bitemporal hemianopia
Lesions at the optic chiasm classically produce a bitemporal hemianopia, however note lesions that spread up from below i.e. pituitary tumours, the defect is worse in the upper fields and if a lesion spreads down from above i.e. craniopharyngiomas, the visual defect is worse in the lower quadrants. Therefore this patient is likely to have a lower bitemporal hemianopia.
A middle aged lady is brought to the clinic by her husband who has noted a change in her appearance. She finds removal of rings difficult, her shoe size has changed and photographs show a marked change in her appearance. Which of the following is most likely to be identified on neurological examination?
Binasal hemianopia Bitemporal hemianopia Inferior quadrantanopia Homonymous hemianopia Unilateral loss of vision
Bitemporal hemianopia
The patient is most likely to have developed acromegaly. Since a pituitary lesion is likely to be present; compression of the optic chiasm may occur.
A 35 year old man is admitted to hospital with vomiting, nausea and severe headaches. An MRI scan reveals a tumour of the cerebellopontine angle. Which one of the following pairs of cranial nerves is most likely to be compressed by this tumour?
Accessory and vagus Facial and vagus Facial and vestibulocochlear Glossopharyngeal and vestibulocochlear Vagus and vestibulocochlear
Facial and vestibulocochlear (CN 7-8)
The cerebellopontine angle is located between the superior and inferior limbs of the angular cerebellopontine fissure formed by the petrosal cerebellar surface folding around the pons and middle cerebellar peduncle.
The cerebellopontine fissure opens medially and has superior and inferior limbs that meet at a lateral apex. The fourth through the eleventh cranial nerves are located near or within the angular space between the two limbs commonly referred to as the cerebellopontine angle.
The commonest lesion to affect this site is an acoustic neuroma. Therefore the vestibulocochlear nerve is commonly compromised. Larger lesions may also affect the facial nerve which lies closest to this site.
What is the most useful test to clinically distinguish between an upper and lower motor neurone lesion of the facial nerve?
Blow cheeks out Loss of chin reflex Close eye Raise eyebrow Open mouth against resistance
Raise eyebrow
UMN lesion = paralysis of lower half of face
LMN = paralysis of entire ipsilateral face
Which cranial nerve provides general sensation to the anterior two thirds of the tongue?
Facial Trigeminal Hypoglossal Vagus Glossopharyngeal
Trigeminal
TASTE to the anterior two thirds of the tongue is supplied by the FACIAL nerve.
The TRIGEMINAL supplies GENERAL sensation, this is mediated by the MANDIBULAR branch of the trigeminal nerve (via the LINGUAL nerve).
The recurrent laryngeal is connected to which of the following nerves?
Trigeminal Accessory Hypoglossal Vagus Glossopharyngeal
Vagus nerve
RLN innervates the intrinsic larynx muscles (excluding cricothyroid)
Following a carotid endarterectomy a man notices that he has a weakness of his tongue. Damage to which of the following nerves is the most likely explanation for this process?
Hypoglossal Accessory Ansa cervicalis Vagus Cervical plexus
Hypoglossal
The hypoglossal nerve innervates the tongue and is one of the structures more commonly at risk in carotid surgery.
