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1

A 66-year-old woman complains of stiffness and weakness climbing stairs. She has a history of hypertension and diet-controlled type 2 diabetes. On examination, there is mild upper arm weakness, hip flexion is 4−/5 bilaterally, with bilateral wasting and flickers of fasciculations in the right quadriceps. Knee extension is 4/5.

Dorsiflexion and plantar flexion are strong. Brisk knee and ankle reflexes are
elicited, as well as a positive Hoffman’s and Babinski’s sign. Sensory examination and cranial nerves are normal. Her BM is 8.9, her pulse is regular and her blood pressure is 178/97. What is the most likely diagnosis?


A. Myasthenia gravis
B. Diabetic neuropathy
C. Myositis
D. Motor neurone disease
E. Multiple sclerosis (MS)

D

  • Woman presents with upper (brisk reflexes, upgoing plantar) and lower (fasciculations) motor neurone signs
  • Motor neurone disease presents with mixed upper and lower motor neurone signs and importantly no sensory involvement 
  • In this case there is involvement of two regions (arms and legs) 
  • Bulbar signs such as tongue wasting and fasciculation often help make the diagnosis
  • Myositis affects the muscle resulting in:
    • tenderness
    • wasting
    • fasciculation 
    • But no upper motor neurone signs
  • Although patient is diabetic - neuropathies only result in lower motor neurone signs 
  • There may be motor and/or sensory.
  • Typically, diabetes results in peripheral neuropathy - most commonly sensory 
  • Proximal distribution of weakness would be in keeping with myasthenia but not the UMN signs
  • No mention of fatigability, which is a key feature 
  • MS in this age group is less common and an inflammatory disorder of the CNS would not result in LMN signs 

2

A 23-year-old man is stabbed in the neck. Once stabilized, his MRI shows a right
hemisection of the cord at C6. What is the expected result of this injury?


A. Paralysed diaphragm
B. Absent sensation to temperature in the left hand
C. Paralysis of the left hand
D. Absent sensation to light touch in the left hand
E. Brisk right biceps reflex

B

  • Hemisection of the cord ⇒ Brown-Sequard syndrome 
    • Results in ipsilatral paralysis and loss of light touch and vibration sensation and contralateral loss in pain and temperature below the point of the lesion 
  • Spinothalamic tracts cross at the level of the cord so sensation to pain and temperature would be lost in the contralateral limbs 
  • C3, C4 and C5 keep the diaphgram alive, so breathing should be preserved.
  • Right corticospinal tract has been severed ⇒ right, ipsilateral hand would be paralysed as well as the right leg 
  • Left dorsal columns carry light touch fibers from the left limb 
  • They have been unaffected by the injury 
    • C6 is responsible for the biceps reflex and would be lost
    • Reflexes distal to the lesion would be brisk 

3

A 23-year-old woman complains that her right leg has become progressively stiff and clumsy over the last couple of weeks. She is worried as she has not been able to go to work for the last 4 days. On examination, tone is increased and there is a catch at the knee. She has six beats of clonus and an upgoing plantar. Power is reduced to 3-4/5 in the right leg flexors. There is no sensory involvement and the rest of the neurological exam is normal other than a pale disc on opthalmoscopy. On further questioning, she admits that she has had two episodes of blurred vision in her right eye in the last two years. Each lasted a couple of weeks from which she fully recovered. What is the most appropriate initial treatment?


A. A non-steroidal anti-inflammatory drug (NSAID)
B. Interferon-beta
C. Bed rest
D. Methotrexate
E. A course of oral steroids

E

  • Subacute onset of upper motor neurone signs on a background of episodes of optic neuritis in a young woman makes relapsing-remitting MS the most likely diagnosis
  • The diagnosis of MS hinges on the presence of multiple CNS lesions separated by time and space 
  • These manifest in either signs/symptoms or as enhancing white matter lesions on gadolinium-enhanced MRI
    • There is no specific role for NSAIDs in MS
  • Even if patient complained of pain it would be important to ensure its origin 
  • NSAIDs would not be appropriate for neuropathic pain 
  • Patient ⇒ eligible for disease-modifying drugs such as interferon beta or glatiramer acetate as she has a relapsing-remitting course and recent symptoms ==> this would not be the immediate treatment 
    • These drugs reduce the number of relapses experienced by one third over two years and are expensive 
  • Long term effects on morbidity remain unclear 
  • Bed rest alone is inappropriate as this patient would benefit from a course of steroids as she has disabling symptoms 
  • Oral steroids have been shown to be as effective as IV steroids although patients tend to admitted for IV treatment
  • They reduce the length of relapse so the patient would recover quicker, but have no effect on number of relapses or accumulation of disability
  • There is no evidence for methotrexate in relapsing-remitting MS

4

A 78 year old right-handed male collapses and is brought into accident and
emergency. He seems to follow clear one-step commands but he gets very frustrated as he cannot answer questions. He is unable to lift his right hand or leg. He has an irregularly irregular pulse and his blood pressure is 149/87. He takes only aspirin and frusemide. What is the most likely diagnosis?


A. Left cortical infarct
B. Right internal capsule infarct
C. Left cortical haemorrhage
D. Left internal capsule haemorrhage
E. Brainstem haemorrhage

A

  • Most likely suffered a left cortical infarct ⇒  probably as a result of an embolus secondary to atrial fibrillation 
  • Treatment with warfarin wouldhave reduced his annual risk of stroke from roughly 5 to 1 percent.
    • A left sided infarct because of the contralateral (right) hemiparesis and dysphasia (involvement of the dominant cortex 
  • It is not a capsular or brainstem event as the patient has an expressive dysphasia which implies involvement of Broca's area which is cortical 
  • It is more likely to be ischaemic than haemorrhagic 
    • Roughly 80% of strokes are infarcts, 20% are haemorrhagic and in this case there is a plausible embolic explanation coupled with only mild hypertension 
  • Haemorrhagic strokes tend to occur in younger patients with severe hypertension and a family history (pointing to an anatomical anomaly) 
  • However, the differentiation requires a CT scan

5

A 19-year-old woman collapses at a concert and is witnessed to have a tonic-clonic seizure lasting 2 minutes. When the paramedics arrive and ask her questions, she mumbles but no-one can understand what she is saying. Only when the paramedic applies pressure to her nailbed does she open her eyes and reach out with her other hand to rub her nail and then push him away. What is her Glasgow Coma Scale (GCS)?


A. 12
B. 11
C. 10
D. 9
E. 8

D

The GCS is frequently used to assess level of consciousness. The lowest
score is 3, the highest 15. A score of 8 or below is classified as coma. GCS
is assessed by evaluating eye (1–4), verbal (1–5) and motor (1–6) response.
Clinically, it is best to assess for the highest possible score and work down.
So, if a patient is not opening their eyes spontaneously, assess whether
they respond to verbal command and only then to pain. In this case, E = 2
(responds to pain), V = 2 (incomprehensible sounds), M = 5 (localizes to
pain), giving this patient a GCS of 9/15. It is important to carefully monitor
her GCS, like most measurements a trend is more useful than a one-off
assessment.

6

A 79-year-old man is admitted with left hemiparesis. CT reveals a middle cerebral artery infarct. What is his most significant risk factor for stroke?


A. Hypertension
B. Smoking
C. Family history
D. Diabetes
E. Cholesterol

A

The three most important risk factors for stroke are hypertension, hypertension
and hypertension (A)! INTERSTROKE, a recent large case–control study evaluating risk factors for stroke, has shown that ten risk factors are associated with 90 per cent of the risk of stroke and that of these modifiable risk factors, hypertension is the most important for all stroke subtypes and is a particularly dangerous risk factor for intracerebral haemorrhage.

Other risk factors include smoking (B), lipids (E) and diabetes (D) which promote atherosclerosis. Poor diet, lack of regular activity and increased waist–hip ratio are as significant risk factors as smoking.

Unmodifiable risk factors include increasing age (by far the most significant), male sex, family history (C) and ethnicity (higher in Blacks and Asians). Patients in atrial fibrillation have an annual stroke risk of 5 per cent. This can be lowered to 1 per cent by anticoagulating with warfarin, aiming for an international normalized ratio (INR) of
between 2 and 3 (avoid confusion with aspirin which is an antiplatelet).


Stroke is the third most common cause of death in England (after heart
disease and cancer) and is more often disabling than fatal, so primary and
secondary prevention are crucial.

7

A 42-year-old woman presents with ataxia. Gadolinium-enhanced MRI reveals
multiple subcortical white matter lesions as well as enhancing lesions in the
cerrebellum and spinal cord. She is diagnosed with MS. Two months later she
develops optic neuritis. What feature is associated with a milder disease course?


A. Her age of 42
B. Her initial presentation of ataxia
C. Her female gender
D. The interval between the two episodes of two months
E. Her MRI scan appearance

C

In this woman’s case, all of the features except her gender (C) point to a
more aggressive disease course. Although it is close to impossible to
predict an individual patient's outcome, features of a better prognosis
include onset under 25 years (A), optic neuritis or sensory, rather than
cerebellar symptoms on initial presentation (B), a long interval (>1 year)
between relapses (D) and few lesions on MRI (E). Full recovery from
relapses is also a positive feature. Progressive MS carries a poorer prognosis
compared to relapsing–remitting MS.

8

A 71-year-old man with atrial fibrillation is seen in clinic following an episode of
syncope. He describes getting a poor night’s sleep and, as he got out of bed in the morning, feeling dizzy for a couple of seconds before the lights dimmed around him. He was woken a couple of seconds later by his wife who had witnessed the event. She says he went pale and fell to the floor and his arms and legs jerked. After waking, he was shaken but was ‘back to normal’ a few minutes after the event. His medication includes aspirin, atenolol and frusemide. What is the most likely diagnosis?


A. Vasovagal syncope
B. Orthostatic hypotension
C. Cardiogenic syncope
D. Transient ischaemic attack (TIA)
E. Seizure

B

This man most likely experienced an episode of orthostatic or postural
hypotension (B) where syncope occurs as a result of reduced cerebral
perfusion as the patient moves from lying to standing. Symptoms are
similar to vasovagal in that the patient may become pale and describe ‘the
lights or sound dimming’. Perfusion is restored after the patient collapses
and unconsciousness lasts no more than seconds or a couple of minutes
with full recovery. However, vasovagal epsiodes (A) can be brought on by
sleep or food deprivation, hot or emotional environments, Valsalva
manoeuvre (such as straining) and are not as closely related to position.
Syncope while lying down is more suggestive of cardiac syncope or seizure
activity. It is important to rule out cardiac causes of syncope (C) which
may be heralded by chest pain or palpitations. Arrhythmias or aortic
stenosis may be the underlying cause. TIAs (D) are a very rare cause of
syncope. Seizures (E) may be triggered by lack of sleep. They may be
heralded by an aura, typically visual or olfactory. There may be urinary
incontinence, tonic-clonic movements, tongue-biting and cyanosis during the event. However, jerky movements may occur in syncope of any cause.

This alone does not equate to a seizure.

9

A 41-year-old man complains of terrible headache. It started an hour ago, without warning, while stressed at work. It affects the right side of his head. He scores it ‘11/10’ in severity. When asked, he agrees that light does bother him a little. He had a similar episode six months ago, experiencing very similar headaches over 2 weeks which resolved spontaneously. On observation, he looks quite distressed and prefers to pace up and down, unable to sit still. What is the diagnosis?


A. Subarachnoid haemorrhage
B. Tension headache
C. Intracerebral haemorrhage
D. Migraine
E. Cluster headache

E

Cluster headache (E) is more common in men and is classically excruciating,
unilateral headache associated with autonomic features such as miosis,
ptosis, conjunctival injection, tearing, sensation of nasal congestion and
facial flushing.

Timing is important, headaches occur in clusters of multiple
episodes over a couple of weeks, then resolve spontaneously only to
reoccur months to years later.

They are not associated with aura or signs of raised intracranial pressure.

Although the headache is severe and of acute onset in this instance, with possible photophobia, there is nothing in the stem to suggest raised intracranial pressure, such as papilloedema, nausea and vomiting or meningism, such as nuchal rigidity (A).

More importantly, he has had similar episodes in the past. The timing and mautonomic symptoms point to cluster headache.

Tension headache (B) is classically associated with stress, reported as a tight band around the head and is much more benign.

Intracranial haemorrhage (C), depending on location, is likely to cause focal signs or, especially if posterior fossa, signs of raised intracranial pressure and coning. Hypertension is an important risk factor.

Migraine (D) classically is heralded by an aura and is associated with nausea and vomiting with osmo- (smell), phono- (sound) and photophobia. Patients prefer to curl up in a dark, quiet room, whereas patients with cluster headache feel the need to move around.

10

A 49-year-old man complains of sudden onset, painless unilateral visual loss
lasting about a minute. He describes ‘a black curtain coming down’. His blood
pressure is 158/90, heart rate 73 bpm. There is an audible bruit on auscultation of his neck. His past medical history is insignificant other than deep vein thrombosis of his right leg ten years ago. The most likely diagnosis is:


A. Retinal vein thrombosis
B. Retinal artery occlusion
C. Amaurosis fugax
D. Optic neuritis
E. Acute angle glaucoma

C

This man gives a classical description of amaurosis fugax (C), painless,
unilateral visual loss of short duration described as ‘a black curtain
descending’, caused by retinal artery emboli, with a likely cardiac source
as a consequence of atrial fibrillation.


Retinal artery (B) and vein (A) occlusion are also painless and of sudden
onset, but they typically occur in older patients and result in prolonged
visual loss. Amaurosis fugax may herald retinal artery occlusion which is
confirmed on ophthalmoscopy showing oedema and a cherry red macula. It
is also a complication of giant cell (temporal) arteritis.

Retinal haemorrhages and cotton wool spots are typically seen in retinal vein occlusion. Optic neuritis (D) is associated with MS and patients complain of painful, blurred
vision.

Acute angle glaucoma (E), again seen in older patients, presents with
painful, blurred vision. Patients describe ‘seeing haloes around things’.

11

A 77-year-old woman is admitted to hospital with a urinary tract infection. She
receives antibiotics and seems to be responding well. On the fourth day she is eating her lunch when she suddenly drops her fork. She calls for the nurse who notices the left side of her face is drooping. What is the best next course of action?

A. CT head
B. Thrombolysis
C. MRI head
D. Aspirin
E. Place nil by mouth

E

This patient has suffered a stroke. This is a medical emergency. As she is
within the 3-hour window for thrombolysis (B), she must be assessed immediately. However, thrombolysis is only useful in ischaemic stroke and can severely worsen haemorrhagic stroke.

It is impossible to clinically tell the difference with certainty; she therefore warrants urgent imaging.

Haemorrhages are much easier to detect on CT (A) as blood shows up white (hyperdense), plus there is easier access to CT unlike MRI (C) which is not always available. If thrombolysis is contraindicated, 300 mg of aspirin (D) is given in the case of ischaemic stroke.

Option (E), however, is the most appropriate next step as removing her lunch is a quick, simple intervention that may prevent the complication of aspiration pneumonia.

The nurse can then call the doctors or put out a thrombolysis call.

12

A 71-year-old right-handed male is brought in by ambulance at 17:50 having
suffered a collapse. His wife came home to find him on the floor unable to move his right arm or leg and unable to speak. Her call to the ambulance was logged at 17:30. He has a past medical history of well-controlled hypertension, ischaemic heart disease and atrial fibrillation for which he is on warfarin. He had a hernia repair three months ago and his brother had a ‘bleed in the brain’ at the age of 67. What is the absolute contraindication to thrombolysis in this male?


A. Family history of haemorrhagic stroke
B. History of recent surgery
C. Time of onset
D. Current haemorrhagic stroke
E. Warfarin treatment

C

This man presents with a stroke. It is clinically impossible to tell with
certainty whether it is ischaemic or haemorrhagic (D) which is why he needs
a CT to differentiate between the two.

However, the time of onset is unclear and therefore it is not possible to determine whether he is outside the 3-hour time window for thrombolysis (C).

Neither warfarin treatment (E) nor family history of haemorrhagic stroke (A) are absolute contraindications although they would be taken into consideration. INR should be <1.7.

The absolute contraindications for thrombolysis are: onset of symptoms more than 3
hours ago, seizures at presentation, uncontrolled blood pressure (over
180/110), previous intracranial bleed, lumbar puncture in the last week,
ischaemic stroke or head injury in the last three months, active bleeding (not
menstruation), surgery (B) or major trauma (including CPR) within the last
2 weeks or non-compressible arterial puncture within the last week.

13

A 69-year-old man presents to clinic with a six-month history of progressive lower back pain which radiates down to his buttock. He found the pain was exacerbated while taking his daily morning walk and noticed that it eased going uphill but worsened downhill. He stopped his daily walks as a result and he now walks only slowly to the shops when he needs to, taking breaks to sit down and ease the pain. He has a history of hypertension, diabetes and prostatic hyperplasia. What is the diagnosis?


A. Peripheral vascular disease
B. Osteoporotic fracture
C. Spinal stenosis
D. Sciatica
E. Metastatic bone disease

C

  • Good history of spinal claudication evidenced in this patient history ==> lower back pain and sciatica on walking 
    • Pain worsens when the spine is extended (walking, especially downhill and improves when flexed going uphill or sitting)
    • Caused by narrowing of the spinal canal as a result of spondylosis (degenerative disease)
    • Intermittent claudication from peripheral vascular disease can be similar in timing, worse on walking and relieved by rest but the pain comes from ischaemic muscles, typically calf or buttock and has no relation to the incline 
    • There is nothing to suggest osteoporotic fracture and in addition his sex iss protective for osteoperosis 
    • Sciatica presents as sharp pain shooting down the posterior leg and occur as a result of impingement of the nerve root forming the sciatic nerve 
      • It is a symptom rather than a diagnosis
    • Metastatic bone disease could result in spinal stenosis or sciatica but in itself does not explain the patient's exact symptoms and there is nothing to suggest malignancy in the stem such as constitutional symptoms or a nodular prostate 

14

A 31-year-old woman presents to accident and emergency with progressive
difficulty walking associated with lower back pain. A few days ago she was tripping over things, now she has difficulty climbing stairs. She describes tingling and numbness in both hands which moved up to her elbows, she is unable to write. On examination, cranial nerves are intact but there is absent sensation to vibration and pin prick in her upper limbs to the elbow and lower limbs to the hip. Power is 3/5 in the ankles and 4−/5 at the hip with absent reflexes and mute plantars. Her blood pressure is 124/85, pulse 68 and sats 98 per cent on air. She has a past medical history of type I diabetes and recently recovered from an episode of food poisoning a month or two ago. What is the diagnosis?


A. MS
B. Guillain–Barré syndrome (GBS)
C. Myasthenia gravis
D. Diabetic neuropathy
E. Infective neuropathy

B

This woman presents with an ascending polyneuropathy. Her symptoms start distally and progress proximally, giving a glove and stocking distribution. Both sensory and motor neurones are involved. This is consistent with Guillain–Barré (B), an inflammatory disorder of the peripheral nerves often preceded by an infection such as campylobacter gastreoenteritis.

Multiple sclerosis (A) is an inflammatory disorder of the central nervous system resulting in upper motor neurone signs – this patient’s reflexes are absent.

Myasthenia gravis (C) is a disorder of the neuromuscular junction and although it results in lower motor neurone signs, there is no sensory involvement and the weakness is greater in proximal muscles and commonly involves the cranial nerves resulting in droopy eyelids, difficulty speaking and swallowing.

A key feature isfatigability as the stores of acetylcholine are used up. Although this
woman is diabetic and has a polyneuropathy, her symptoms progress too
quickly.

Diabetic neuropathy (D) takes time to develop and, although there are different types, most commonly results in a distal sensory neuropathy of the feet.

Vibration and pain are most affected which is why they may have a stomping gait and develop ulcers. Infective neuropathies (E) include Lyme disease from ticks and leprosy which is uncommon in developed countries and she has no history of travel.

15

A left-handed 79-year-old man presents with a troublesome resting tremor of his left hand. The tremor is evident in his writing. He has also noticed his writing is smaller than it used to be. He complains he has difficulty turning in bed to get comfortable and his wife complains that he sometimes kicks her in the middle of the night. When he gets out of bed in the morning he feels a little woozy, but this resolves after a while. On examination, he blinks about three times a minute and his face does not show much emotion. Glabelar tap is positive. He has a slow, shuffling gait. He has difficulty stopping, starting and turning. He holds his feet slightly apart to steady himself. When you pull him backwards, he is unable to right himself and stumbles back. Which of the signs and symptoms is not commonly associated with parkinsonism?


A. Postural instability
B. Rapid eye movement (REM) sleep disturbance
C. Hypomimia
D. Broad-based gait
E. Autonomic instability

D

This man presents with many symptoms of parkinsonism. However, the parkinsonian gait is typically narrow-based, not broad (D).

Parkinson’s is a disease of dopaminergic neurone loss in the nigrostriatal pathways and
results in the triad of bradykinesia, rigidity and tremor. A fourth sign to look out for is postural instability (A).

This can be elicited by asking the patient to steady himself and pulling him backwards. During REM sleep (B), the brain is active but muscles are paralysed (thus associated with dreaming).

In Parkinson’s disease (PD), muscles may be active allowing patients to act out their dreams, resulting in kicking, yelling, etc. Hypomimia (C) is the technical term for mask-like facies or reduced facial expression.

Symptoms of autonomic dysfunction (E) are common and include constipation, postural hypotension and sexual dysfunction. Very prominent autonomic symptoms may suggest Shy–Drager’s, a type of multiple system atrophy (which in turn is one of the Parkinson’s plus syndroms.)

16

A 33-year-old woman attends her six-month follow-up appointment for headache. They are migrainous in nature but whereas she used to have them every few months, over the last three months she has experienced a chronic daily headache which varies in location and can be anywhere from 3–7/10 severity. Her last migraine with aura was two months ago. She takes co-codamol qds and ibuprofen tds. What is the best medical management?


A. Stop all medication
B. Start paracetamol
C. Start sumatriptan
D. Start propranolol
E. Continue current medication

A

  • This woman has developed analgesia (rebound) headache as result of over-using co-codamol and ibuprofen. 
  • Starting paracetamol would result in overdose as it is already contained in co-codamol. 
  • The treatment is to withdraw analgesics which initially will worsen the headache - patient should be prepared for this) but in the long run will alleviate it.
  • It is not advisable for headache patients to take simple analgesia more than 2 days a week
  • Once she is off the analgesia, it will be easier to discern the effect of her migraines
  • She may require abortive sumatriptan to be taken as soon as the headache starts or prophylactic beta blockers taken daily
  • Continuing her current medication will not improve matters

17

A 17-year-old girl is brought into accident and emergency with generalized tonicclonic seizure. Her mother had found her fitting in her bedroom about 20 minutes ago. The ambulance crew handover state that her sats are 96 per cent on 15 L of oxygen and they have given her two doses of rectal diazepam but she has not stopped fitting. What is the most appropriate management?


A. Lorazepam
B. Phenobarbital
C. Intubation
D. Call ITU
E. Phenytoin loading

E

Status epilepticus is a serious condition of continuous seizure activity lasting more than 30 minutes. The mortality rate is one in five. This girl has been fitting for at least 20 minutes despite two doses of diazepam so must urgently be loaded with phenytoin (E) and monitored closely. ITU (D) should be alerted in case phenytoin does not stop the seizure in which case phenobarbital (B) can be considered, but the phenytoin should be given first.

Ultimately, general anaesthetic and intubation (C) may be required. There is increasing evidence that lorazepam (A) is more effective than diazepam, but in this case the patient has already had two doses of benzodiazipine so the next step is phenytoin infusion.

18

A 72-year-old man with known epilepsy and hypertension is admitted with
pneumonia. His drug history includes aspirin, phenytoin, bendroflumethiazide and amlodipine. His heart rate is 67, blood pressure 170/93, sats 96 per cent on 2 L of oxygen. Neurological examination is normal. His doctor requests blood tests including phenytoin level. What is the correct indication for this test?


A. Routine check
B. Ensure levels are not toxic
C. Confirm patient compliance
D. Ensure therapeutic level reached
E. Reassure the patient

C

Routine measurement of phenytoin levels (A) is not good practice, they should be ordered with a question in mind.

They can be helpful either for adjustment of phenytoin dose or looking for toxicity or patient compliance.

Phenytoin levels are useful when adjusting the dose to avoid toxicity as phenytoin has zero-order kinetics (once elimination reaches saturation rates, it cannot be cleared any faster so a small change in the dose may result in high blood levels), but there is no reason to change this patient’s dose.

There is no reason to suspect phenytoin toxicity either (B) as there are no signs or symptoms such as nystagmus, diplopia, dizziness, ataxia, confusion.

However, his high blood pressure may be caused by noncompliance with his medication (C).

Although target levels exist (D), they are imprecise and not applicable to all patients. Seizures may be well controlled with low levels, thus phenytoin should be adjusted according to the clinical picture and not levels. Levels are not helpful in reassuring the
patient in this situation (E), although they often inappropriately reassure
the doctor who requests them.

19

A 23-year-old woman is seen in clinic for recurrent funny turns. She is not aware of them, but her family and friends have noticed them. They say she looks around blankly, then starts picking at her clothes and sometimes yawns, then she comes back after a minute. She can get drowsy after these episodes. What seizure type does this patient describe?


A. Absence
B. Tonic clonic
C. Simple partial
D. Complex partial
E. Generalized

D

  • This woman has complex partial seizures which start focally in the brain (classically temporal lobe) and by definition result in reduced awareness.
  • Patients do not remember the seizure, unlike simple partial seizures where consciousness is maintained 
  • Automatisms typically characterise complex partial seizures where patients carry out repetitive and seemingly purposeless actions such as:
    • chewing
    • lip smacking
    • picking 
    • fumbling 
  • Absence seizures occur in children typically lasting seconds 
    • Children are reported to be staring blankly 
  • Seizures can be difficult to detect as they can be subtle, short lived and the child is unaware of them 
  • Tonic-clonic are classic seizures where patients fall to the ground unconscious and then go through a tonic (tensing) and then clonic (jerking) phase lasting seconds to minutes, typically associated with tongue-biting and incontinence and post-ictal drowsiness 
  • Complex partial seizures may subsequently generalise but this has not been reported by this patient
    • Carbamazepine, lamotrigine and valporate are first line monotherapy

20

You are asked to perform a lower limb peripheral neurological examination on
a 45-year-old diabetic male. The patient has normal tone, 5/5 power, normal
plantars and proprioception. However, you notice that the patient does not respond to any sensory stimulus on the medial side of the right lower leg. Which dermatome is affected?


A. L1
B. L2
C. L3
D. L4
E. L5

D

The dermatomes of the lower leg are important to know when performing
a lower limb neurological examination. If the upper leg is divided into
three equal thirds from the greater trochanter to the knee L1 (A), L2 (B)
and L3 (C) correspond to these dermatome areas. If the lower leg is split
into two sides down to the ankle, the medial side of the leg corresponds to
dermatome L4 (D), while L5 (E) extends from the lateral side of the lower
leg down to the dorsum of the great toe.

21

On examination, a patient has 5/5 power in all muscle groups of his upper limbs,
0/5 power in all the muscle groups of his lower limbs. Cranial nerves are intact.
Where is the lesion?


A. Muscle
B. Neuromuscular junction
C. Peripheral nerves
D. Spinal cord
E. Brain

D

From these limited options, spinal cord (D) is most likely. There is a stark
difference between power in upper and lower limbs making generalized
processes affecting muscle, neuromuscular junction and peripheral nerves less likely.

Muscle (A) or neuromuscular junction (B) lesions tend to have a proximal distribution, while a peripheral neuropathy (C) would have a distal predilection.

For a brain lesion (E) to affect both legs, the lesion would have to be in the midline of the frontal cortex (think back to the homunculus), thus sparing the upper limbs. This is much rarer than a lesion transecting the cord (either thoracic or lumber in this case) to result in paraplegia.

22

On examination, a patient has 5/5 power in his upper limbs, 0/5 power in his lower limbs. Further examination reveals a sensory level at the umbilicus. Cranial nerves are intact. Where is the lesion?


A. C4
B. T4
C. T10
D. L1
E. L3

C

Like the previous question, this patient is paraplegic. The lesion can be
in the thoracic or lumbar cord. A sensory level helps further identify
the location of the lesion. Dermatomes overlap and are not always
consistent. You do not need to be able to delineate every dermatome but it
is useful to have a general idea of certain levels such as: C4 shoulders (A),
T4 nipples (B), T10 umbilicus (C), L1 pockets (D), L3 knee (E) (see
Figure 8.1).

23

A patient is unable to move his right arm or leg. When asked to smile, the left side of his mouth droops. Where is the lesion?


A. Left motor cortex
B. Right motor cortex
C. Left brainstem
D. Right brainstem
E. Cervical spine

C

It is useful to divide the body into the areas such as: face/arms/legs, left/ right, proximal/distal. This allows a rapid diagnosis of where the lesion might be. This patient shows crossed signs.

The left side of the face is affected but so is the right side of his body. Therefore, if the lesion were cortical, there would have to be two lesions to explain this (A and B). As his face is involved, there has to be a lesion above the spinal cord (E).

Crossed signs tend to suggest brainstem involvement (if only one lesion is responsible). In this case a left brainstem lesion (C) would affect cranial nerves exiting on that side (LMN left-sided droop) and the cortical spinal tracts as they descend which then go on to cross at the medulla (UMN right arm and leg weakness).

A right brainstem (D) lesion would cause the opposite. Please note that this is a general rule of thumb and lesions do not always result in textbook deficits.

24

A light is shone into a patient’s right eye and it constricts. When moved to the left eye, the left eye constricts. When moved back to the right eye, the right eye dilates. What is the diagnosis?


A. Afferent lesion
B. Efferent lesion
C. Relative afferent lesion
D. Relative efferent lesion
E. Normal

C

This is the swinging torch test. To recap the pathways, CN II (optic nerve) is the afferent limb that detects light, CN III (occulomotor nerve) is the efferent limb which results in pupillary constriction. Light enters the right eye, is picked up by the right CN II and triggers off both right (direct) and left (consensual) CN III responses. By eliciting the direct light response as described in the vignette, this shows that the afferent and efferent pathways of the right and left eye are grossly intact. Subtleties can be picked up by comparing the two against each other. This is done by moving the light
(stimulus) from one eye to the other.

If the right optic nerve is damaged but still functioning (for example in optic neuritis), the direct and consensual response will appear normal. However, moving the light from the intact left optic nerve to the damaged right optic nerve will result in reduced detection
of the stimulus, thus causing the right eye to abnormally dilate in response
to light.

This is not a normal response (E). This is called a relative afferent pupillary defect (RAPD) (C). It is relative to the other eye, and afferent because CN II (the optic nerve) is the afferent limb (A) of the reflex. The efferent limb (B and D) is CN III which is intact

25

A 55-year-old woman complains of double vision. She finds that she is more tired than usual and has difficulty climbing stairs, especially when they are very long. She has difficulty getting items off high shelves at work and lately even brushing her hair is a problem. During the consultation, her voice fades away during  conversation. Reflexes are present and equal throughout. Which sign or symptom is most indicative of myasthenia gravis?


A. Proximal weakness
B. Normal reflexes
C. Diplopia
D. Fatigability
E. Bulbar symptoms

D

Disease of the muscle and neuromuscular junction can be similar. Both
generally tend to affect proximal muscles (A). Cranially, this may result in
ptosis and ophthalmoplegia (C) as well as bulbar symptoms (E) such as dysphagia and hypophonia.

In both cases, reflexes (B) and muscle bulk tend to be preserved or, if severe and longstanding, reduced. A key clinical feature that differentiates myopathies and MG is fatigability (D).

As patients with myasthenia use their muscles, they exhaust the supply of acetylcholine, resulting in increasing weakness. This can be elicited by asking the patient to repeatedly abduct and adduct one arm and compare it to the other arm that has remained at rest.

Alternatively, you can ask the patient to count to 100 and their voice will fatigue, or ask them to do squats or test neck flexion.

26

A 55-year-old woman complains of double vision. She finds that she is tired all the time and has difficulty climbing stairs. She has difficulty getting items off high shelves at work. Reflexes are absent but elicited after exercise. Shoulder abduction is initially 4−5 but on repeated testing is 4 +/5. What pathology is associated with this female’s diagnosis?


A. Thyrotoxicosis
B. Peptic ulcer
C. Diabetes
D. Stroke
E. Lung cancer

E

In contrast to MG, patients with Lambert–Eaton myasthenic syndrome (LEMS) experience increased strength upon repetition. LEMS is a rare disease caused by autoantibodies against the voltage-gated calcium channels on the presynaptic motor nerve terminal.

It is a paraneoplastic disorder, most often associated with small-cell lung cancer (E), although a variety of underlying malignancies may be the culprit. LEMS may be difficult to differentiate from MG clinically, an EMG is key for diagnosis as well as testing for autoantibodies and searching for underlying malignancy.

MG is associated with other autoimmune disease such as thyrotoxicosis (A), haemolytic and pernicious anaemia, connective tissue disease, as well as thymomas, which is why a thymectomy is often performed. Neither MG nor LEMS are directly associated with petic ulcer, diabetes or stroke (B, C, D).

27

On observation, a patient has a left facial droop. On closer examination his
nasolabial fold is flattened. When asked to smile, the left corner of his mouth
droops. He is unable to keep his cheeks puffed out. Eye closure is only slightly weaker compared to the right and his forehead wrinkles when he is asked to look up high. What is the diagnosis?


A. Right middle cerebral artery stroke
B. Parotid gland tumour
C. Left internal capsule stroke
D. Bell’s palsy
E. Cerebellar pontine angle tumour

A

The patient presents with a CN VII (facial) palsy. The key feature here is forehead sparing which implies an upper motor neuron lesion. This excludes Bell’s palsy (D) and parotid gland (B) or cerebellar pontine angle (CPA) tumours (E) as these would affect the lower motor neuron. In the case of CPA tumours, there is likely to be cerebellar, CN V and CN VIII involvement too.

The most common cause of a lower motor neuron CN VII palsy is Bell’s palsy which is idiopathic and a diagnosis of exclusion. It is treated conservatively with lubricating eye drops and taping down the eye at night to avoid corneal ulcers. Medically, steroids should be given within 48 hours of onset along with acyclovir. Most patients will recover, although around 10 per cent may be left with permanent deficits. An upper motor neuron facial palsy is most commonly due to stroke. In this case, the leftsided symptoms point to a right hemisphere lesion (A, and not C).

28

A female presents with diplopia. On closer examination, when asked to look right, her left eye stays in the midline but her right eye moves right and starts jerking. What is the diagnosis?


A. Myasthenia gravis (MG)
B. Vertigo
C. Cerebellar syndrome
D. MS
E. Peripheral neuropathy

D

This patient has an intranuclear opthalmoplegia (INO). This means that
there is a problem in the communication between CN VI (abducens) of the
right eye and CN III (occulomotor) of the left eye.

Normally these nuclei communicate via the medial longitudinal fasciculus in order to maintain conjugate gaze.

This keeps the eyes aligned on the same spot. If they are not aligned, double vision occurs.

In this patient’s case, there is a lesion in the medial longitudinal fasciculus (MLF). To look right, she abducts her right eye, but as the MLF is affected, she is unable to direct the left eye to adduct to maintain conjugate gaze.

This results in diplopia. The right eye which has abducted fully develops compensatory nystagmus as the left eye has failed to adduct.

Note that the problem is not in the oculomotor nerve or medial rectus. The vestibulo-occular reflex would be intact, i.e. if the patient were to keep her eyes fixed on a target and move her head left, her left eye would adduct normally. Multiple sclerosis (D) is a common cause of INO.

MG (A) often results in ophthalmoplegia (paralysis of one or more extraocular
muscle), but this affects the neuromuscular junction, not the MLF. Cerebellar syndromes (C) would result in nystagmus but not ophthalmoplegia. Peripheral neuropathies (E) are not directly associated with opthalmoplegia or nystagmus. Vertigo (B) is a symptom, not a diagnosis. It is the illusion of movement (i.e. a subjective sensation of movement where there is none).

It is best elicited by asking the patient if they see the room moving. This clearly differentiates it from the vague report of ‘dizziness’ 

29

A neurologist is examining a patient. She takes the patient's middle finger and flicks the distal phalanx, her thumb contracts in response. What sign has been elicited?


A. Chvostek’s
B. Glabellar
C. Hoffman’s
D. Tinel’s
E. Babinksi’s

C

  • The neurologist has elicited a positive Hoffman's reflex suggestie of upper motor neurone disease.
    • It would have been negative if the thumb had not contracted in response to flicking the patient's distal phalanx 
  • Chvostek's sign
    • Contraction of the face on stimulation of the facial nerve on the masseter
      • Seen in hypocalcemia 
  • The glabellar tap is an insensitive test for parkinsonism where the doctor taps above the bridge of the nose and the patient continues to blink 
  • A normal response is to desensitize to the stimulus and stop blinking 
  • Tinel's sign can be elicited by tapping a nerve such as ulnar nerve at the elbow, resulting in a tingling sensation in the distribution of the nerve. 
    • This is a sign of nerve compression. 
    • It is also useful in carpal tunnel syndrome by tapping over the median nerve at the wrist 
    • Babinski's reflex is extension and outward fanning of the toes in response to a firm stimulus of the outer soles
      • Suggestive of upper motor neurone disease

30

A 69-year-old man is taken to his GP by his concerned wife. She complains that he has not been himself for the last year. He has slowly become withdrawn and stopped working on his hobbies. Now she is concerned that he often forgets to brush his teeth. She has noticed he sometimes struggles to find the right word and this has gradually become more noticeable over the last couple of months. She presented today because she was surprised to come home to find him naked and urinating in the living room last week. He has a history of hypertension and is an ex-smoker. The most likely diagnosis is:


A. Depression
B. Frontotemporal dementia
C. Alzheimer’s disease
D. Vascular dementia
E. Lewy Body disease

B

The patient has developed a change in their behaviour. They are initially negative symptoms: withdrawal and disinterest in hobbies (as opposed to positive symptoms such as hallucinations). This would be compatible with depression (A) were it not for the development of word finding difficulties and disinhibition. These localize the problem to the temporal and frontal lobes, respectively (B). Although he is hypertensive, the progression has been gradual as opposed to the classically step-wise progression of
vascular dementia (D), often these patients have had vascular events.

There are no extra-pyramidal (parkinsonian) features to suggest Lewy Body disease (E). Alzheimer’s disease (C) tends to affect memory and language before personality. There may be a family history, especially in someone this age, but becomes increasingly common with age. It is important to note that dementias are definitively diagnosed on biopsy/ autopsy, but this is rarely done.

Differentiating between the dementias on clinical grounds can be difficult. Brain imaging may help visualizing subcortical infarcts and cortical atrophy.