HNNS Supplementary Questions Flashcards
How many pairs of cranial nerves are there?
12
Which of the following statements may be correct regarding human nervous system?
A. Most cranial nerves belong to CNS because they attach to brain
B. Weight of adult brain is one-tenth of body weight
C. Glial cells have short processes called dendrites
D. Smarter people have more neurones
D
B: 1.X kg, ~2% only
Which of the following is true for brainstem?
A. It is a part of PNS
B. Medulla is superior to midbrain
C. Degeneration of neurones in midbrain will lead to Parkinson’s disease
D. Pons is connected to pituitary glands
E. Vagus nerve is originated from midbrain
C
Young driver in car crash. On ventilator. Cannot breathe. Where is respiratory centre?
A. Brainstem
B. Cerebellum
C. Thalamus
D. Amygdala
E. Cerebrum
A
A 32-year-old woman presents to the Emergency Department with progressive weakness of her lower limbs. Her symptoms started two days previously when she noticed her legs felt heavy when rising from a seated position. This weakness has progressed to the point now where she is unable to stand unassisted and has now started to affect some of the muscles of her abdominal wall and lower back. She is otherwise well, apart from suffering a diarrhoeal illness 10 days previously. Neurological examination of the lower limbs identifies generalised weakness, reduced tone and absent reflexes; sensory examination is unremarkable.
Which of the following organisms is most likely to have caused this patient’s diarrhoeal symptoms?
A. Bacillus cereus
B. Campylobacter jejuni
C. Escherichia coli
D. Shigella
E. Staphylococcus aureus
B
Guillain-Barré syndrome (GBS) is classically triggered by Campylobacter jejuni infection
Ascending muscle weakness, no sensory signs
Hyporeflexia, hypotonia: LMN lesion
Preceding diarrhoeal episode
=> GBS (autoimmune-mediated demyelinating disease of PNS)
B. cereus: food poisoning from rice
E. coli: watery stools, abdominal cramps, common among travellers
Shigella: bloody diarrhoea, abdominal pain, vomiting
S. aureus: severe vomiting
An 81-year-old woman is seen in falls clinic after having four falls in the last four months. She has no history of falls previous to this. She also reports experiencing a progressive headache that is worse a night over the last three months.
Upon performing a cranial nerve exam, an inferior homonymous quadrantanopia is elicited although eye movements are preserved. The rest of the cranial nerve examination as well as a full neurological examination is normal.
A lesion located in which area would result in these symptoms?
A. Inferior optic radiation
B. Lateral optic chiasm
C. Optic nerve
D. Superior optic chiasm
E. Superior optic radiation
E
Inferior homonymous quadrantanopias are caused by lesions of the superior optic radiations in the parietal lobe
Complete / Superior optic chiasm lesion:
- bitemporal hemianopia
Lateral optic chiasm lesion
- binasal hemianopia
Roger is a 32-year-old man presenting with diplopia. He is known to have type 1 diabetes and multiple sclerosis. He had been experiencing double vision over the last 3 days. This predominantly happens when he looks to the right.
He denies any associated double vision on vertical vision. He has not noticed any difficulty in moving his eyelids. He has not noticed any increased sensitivity to light and his eye is not red.
On examination, both eyelids display normal strength. With the left eye closed, the right eye displays a full range of movement. With the right eye closed, the left eye fails to adduct when looking towards the right. Nystagmus on the right eye is noted when the patient is asked to look to the right with both eyes. On convergence, both eyes can adduct towards the midline. The pupillary exam is normal with both pupils reacting appropriately to light.
What is the underlying pathology that has caused his diplopia?
A. Extrinsic compression of left oculomotor nerve
B. Intrinsic vascular damage to the left oculomotor nerve
C. Lesion of the left abducens nerve
D. Lesion on the left paramedian area of pons and medulla
E. Lesion on the left paramedian area of the midbrain and pons
E
Medial longitudinal fasciculus:
- on paramedian area of midbrain and pons
Centres of vision:
- mostly midbrain & superior pons
- lower pons & medulla: nuclei of CN V-XII
Internuclear ophthalmoplegia:
- disorder of conjugate gaze
- lesion in MLF => failure of ipsilateral eye to adduct
- younger patients: multiple sclerosis (demyelinating)
- older patients: stroke
- maintained convergence: due to intact CN III and EW n.
Oculomotor nerve palsy:
- ptosis (levator palpebrae superioris)
- lack of pupillary response on ipsilateral side
- failure of adduction on convergence
- surgical 3rd nerve palsy (external compression) causes: aneurysmal compression, malignancy
- medical 3rd nerve palsy (pupil sparing) causes: intrinsic vascular damage, atherosclerotic changes, DM
CN VI lesion:
- failure of abduction rather than adduction
A 45-year-old woman presents with double vision that worsens when reading. She recently had a minor head injury. There is no ptosis or limitation of eye movements. The diplopia disappears when she tilts her head towards the right shoulder.
Which cranial nerve is most likely affected?
A. Abducens nerve
B. Oculomotor nerve
C. Optic nerve
D. Trochlear nerve
E. Vestibulocochlear nerve
D
Vertical diplopia
- Classically noticed when reading a book in downgaze
- Left CN IV palsy => compensatory head tilt to the right
Horizontal diplopia
- CN VI
E.g. Right CN VI palsy => horizontal diplopia when looking to the right
CN III palsy
- ptosis
- pupillary dilation
- eye deviation down and out
CN VIII lesion
- hearing loss
- vertigo
- nystagmus
What is true about palate?
A. Under mucous membrane of palate is palatine tonsil
B. It is in the floor of mouth and connects with tongue
C. Muscle of palate will close to block pharynx when swallowing
D. There is no mucous membrane in palate
C
What are the first teeth that erupt in infants?
A. 1st premolar in upper jaw
B. Canine in upper jaw
C. 1st molar in lower jaw
D. Wisdom teeth in lower jaw
E. Central incisors in lower jaw
E
Which of the following is involved in deglutition?
A. Palatine arches
B. Soft palate
C. Salivary glands
D. Hard palate
E. Tonsils
B
The zygomatic arch encloses which two fossae?
Temporal fossa
Infratemporal fossa
The angle of the mandible is roughened for which muscles to insert?
Outside: masseter
Inside: medial pterygoid
Which two muscles arise from mental spine?
Geniohyoid (inferior genial tubercle)
Genioglossus (superior genial tubercle)
Which two nerves exit through mental foramen?
Mental nerve
Incisive nerve
= terminal branches of inferior alveolar nerve
