Neurology Flashcards
What does a negative Romberg test means?
A Romberg test is negative if the patient is able to stay stable during the test and have minimal swaying.
This means that the vestibular or proprioceptive symptoms may not be related to balancing issues.
Thus, is a patient is ataxic with a negative Romberg test, it suggests that the ataxia is cerebellar in nature, not sensory.
How to differentiate cortical strokes (caused by MCA, ARA and PCA)?
Cortical strokes cause focal motor deficits.
Middle cerebral artery (FACE)
- most common cerebral occlusion site
- contralateral hemiplegia
- contralateral hemianasthesia
- dysarthria due to facial weakness
- can cause homonymous hemianopia, but less common than PCA
Anterior cerebral artery (LEG)
- relatively rare
- motor deficits of the contralateral lower limb
- lesser degree paresis of the contralateral arm
- urinary incontinence and altered phychiatric status can also occur
Posterior cerebral artery (VISION)
- homonymous hemianopia (not a complete loss of vision)
Internal carotid artery stroke is the only one that causes complete loss of vision.
How to diagnose subarachnoid haemorrhage?
- CT scan without contrast
- Lumbar puncture (if the CT is negative but the history is suggestive, a LP should be undertaken)
- MRI (can be more sensitive than CT, but only after several days have passed
After the bleeding is confirmed, its origin needs to be determined. The choice then is between cerebral angiography and CT angiography to identify aneurisms.
Subarachnoid heamorrhages can be associated to which conditions?
Hypertension, polycystic kidney disease, Ehler Danlos syndrome, hyponatremia (due to syndrome of inappropriate antidiuretic hormone)
SAH - SIADH
Under which circumstances can epileptic patients drive?
Drivers of cars or motorbikes who suffer from epileptic seizures while awake and lose consciousness can continue to drive provided they have been
- seizure-free for the last year, or
- seizure-free for more than 6 months of anti-epileptic drugs were changed
What is syringomyelia? What are its features? How does it differ from syringobulbia?
Syringomyelia is a rare condition in which there is a fluid-filled tubular cyst (syrinx) within the central (usually cervical), spinal cord.
- upper limb pain exacerbated by exertion or coughing
- sensory loss of pain and temperature senses of upper limbs (may present with burns as the patient doesn’t feel)
- paraparesis (partial paralysis of lower limbs)
- muscle wasting and weakness in hands, forearms and shoulders
- cape-like bilateral loss of pain and temperature sensation along the upper chest and arms
- loss of tendon reflexes
Syringobulbia occurs when the syrinx extends into the brainstem, affecting cranial nerves, which can result in facial palsies and eventually affect the function of the lower brain stem, producing respiratory failure and death
What should be suspected in a patient presenting with dizziness, difficulty walking and slurred speech? Which imaging method should be ordered as initial, and as choice for diagnosing this condition?
Cerebellar infarction, which requires imagem that is capable of accurately visualising the posterior fossa.
Initial - CT head
Choice - MRI head
Which structures are impaired in chronic alcoholic patients, leading to memory loss?
The critical structures that could lead to memory impairment in patients who suffer from Wernicke-Korsakoff syndrome are the mammillary bodies and the thalamic regions. Atrophy of the mammillary bodies can be seen
Which diagnosis to suspect in a patient with difficulty in swallowing and walking?
Motor neuron disease
Which diagnosis to suspect in a patient with rapid onset confusion and hallucinations?
Hyponatraemia
What differentiates Wernicke’s encephalopathy from Korsakoff’s syndrome?
WE
- triad of confusion + ataxia + ophthalmoplegia
- caused by B1 deficiency
- also seen in pregnancy with severe persistent hyperemesis gravidarum
KS = WE + amnesia + confabulation
What are the features of parkinson’s disease?
- above 65 yo
- bradykinesia
- rigidity
- resting tremor
- postural instability
What are the characteristics of CSF in bacterial meningitis, viral meningitis, and tuberculous meningitis?
Bacterial: low glucose, high protein, neutrophils
Viral: normal glucose, normal-high protein, lymphocytes
Tuberculous: low glucose, high protein, neutrophils in early disease and lymphocytes later
What is the most likely gram positive organism to cause meningitis?
Streptococcus pneumoniae, since Neisseria meningitidis is gram negative
What should be suspected in a patient with gait disturbance, urinary incontinence, and cognitive dysfunction in an elderly patient?
Normal pressure hydrocephalus.
It’s different from parkinsons, since NPH presents with less rigidity and tremors, and doesn’t responde to levodopa. And it’s different from Alzheimer’s, since NPH has a much slower progressive memory loss
What should be suspected in a patient with acute onset of double vision, vertigo, paraesthesia of upper limbs, and unsteady gait? How does it differ from cerebellar infarcts?
Brain stem should be an important differential in a patient with acute vertigo with neurological symptoms.
The hallmark of brain stem strokes are symptoms of vertigo, ataxia and diplopia.
Brainstem strokes cause gross, global motor weakness. A lesion that affects both the ipsilateral and contralateral side of the body, as well as the entire side of the body, think of brainstem strokes.
They differ from cerebellar infarcts (that also present with acute vertigo) because those never have limb paresthesia or diplopia. Those can also present with nystagmus and dysarthria
Both of those differ from cortical lesions, which affect the contralateral side alone, and affect either the upper limb or lower limb.
What are the definitions for Horner’s syndrome and Pancoast tumor? What is the most likely underlying mechanism for the syndrome?
Pancoast tumours are located in the apex of the lung, causing compression of the ipsilateral sympathetic chain, which result in symptoms of Horner’s syndrome (unilateral ptosis, anhidrosis and miosis)
Which medications can be used for migraine prophylaxis?
Topiramate, propranolol and amitriptyline
What should be suspected in a patient who had flu-like symptoms that follow with rapid deterioration like fever, neck stiffness, and confusion?
Encephalitis
What should be suspected in a patient with confusion and hyponatraemia followed by infusion of 5% dextrose in NaCl 0.45% IV?
Cerebral oedema.
Causes of hyponatraemia: high blood sugar and iatrogenic administration of hypotonic solution
Hyponatraemia = diluted blood = water shifts into the brain
On the other side, osmotic shrinkage and even cerebral demyelination would occur after iatrogenic rapid correction of low blood sodium levels.
“From low to high, pons will die. From high to low, your brain will blow”
What should be suspected in a patient with proximal weakness at the pelvic or shoulder girdle, which improves with exercise, as well as reflexes that improve with exercises, in addition to dysphagia, dysarthria, ptosis or diplopia? Which disease is it associated to? And how to differentiate it from miastenia gravis?
Suspect of Lambert-Eaton syndrome is an autoimmune/ paraneoplastic disorder associated with small cell lung cancer.
It differs from myastenia gravis because the patient has increased strength on repetition of power.
Which are of CNS would cause symptoms of diabetes insipidus when damaged?
Diencephalon, which consists of the thalamus, the hypothalamus (including the posterior pituitary), the epithalamus and subthalamus.
Diencephalon for DI
What is the suspected diagnosis and treatment for a patient with sharp shooting unilateral pain?
Trigeminal neuralgia, which is typically confined to the area supplied by the second and third divisions of the trigeminal nerve.
Anticonvulsants like carbamazepine has been shown to dramatically relief the pain.
What should be suspected in a patient with intermittent diplopia and droopy eyelid after working in the computer for several hours?
Myasthenia Gravis, which is a neuromuscular junction disorder that can lead to fatiguability of the limbs, ocular, speech and swallowing muscles.
It often presents with diplopia and ptosis.
Mnemonic to remember clinica features:
- diplopia
- drooping eyelids
- dysphagia
- dysarthria
- dysphonia
Which medications should be avoided when dealing with a patient who has Parkinson’s disease and is having a delirium episode?
It’s important not to prescribe medications that can worsen the symptoms, meaning medications that block dopamine receptors or that mimic the symptoms of PD.
Medications to avoid: haloperidol, olanzapine, chlorpromazine, risperidone, metoclopramide, cinnarazine, prochlorperazine
Medications of choice: lorazepam, clonazepam, ondansetron, cyclizine
What is the treatment for Alzheimer’s disease?
People with Alzheimer’s have low levels of Ach and these medications work to increase the level of Ach available for neurotransmission by inhibiting the enzyme that breaks it down. These drugs also reduce heart rate and can induce bradycardia; once of the potential contraindications of AchEI is left bundle branch block.
1st line - acetylcholinesterase inhibitors
- donepezil
- galantamine
- rivastigmine
2nd line and severe cases
- memantine - not an AchEI, it blocks the effects of excess glutamate in the brain
How to differentiate extradural (epidural) and subdural haematomas in CT imaging?
Epidural - expanding lemon
Subdural - selfish banana
What should be suspected in a patient with unexplained unilateral leg weakness and a positive Hoover’s sign?
Functional weakness
Where should a patient with suspected epilepsy be referred to?
First-fit clinic, where a neurology team will se the patient in a few days to take a full history and provide a management plan
What to suspect if an elderly or alcoholic patient deteriorates after a minor head trauma followed by a lucid interval?
Subdural haematoma, which may develop soon afte a moderate head injury and features such as ipsilateral pupillary dilatation, and raised intracranial pressure may eventually manifest if the haematoma expands and enlarges.
What are the differences and similarities between Ramsay Hunt syndrome and Bell’s palsy?
Ramsay Hunt syndrome (herpes zoster oticus)
- reactivation of varicella zoster virus
- facial paralysis + pain
- painful vesicular rashes around the ear
- tt: ativirals 72h from rash onset, could be prescribed up to a week from rash onset + combined with prednisolone
Bell’s palsy
- well patient presenting with only ipsilateral facial paralysis
- tt: prednisolone 72h from symptoms onset
How to differentiate frontotemporal dementia, Alzheimer’s, vascular dementia, and Lewy body disease?
Frontotemporal dementia - patient struggling with word choice (temporal lobe) and disinhibition (frontal lobe)
Alzheimer’s - presents with memory loss before changes in personality
Vascular dementia - ‘step-wise’ progression + previous cardiac/vascular event
Lewy body disease - parkinsonian symptoms
How to manage stroke or TIA in the long term?
These medications should be used everyday
- Statins (usually atorvastatin 80mg)
- Antiplatelet or anticoagulation treatment (if AFib, prescribe warfarin or DOAC; if sinus rhythm, prescribe clopidogrel)
- Antihypertensives - as needed, to keep target BP 130/80
- age > or = 55, start CCB
- age < 55, start ACEI or ARA
For acute treatment of ischaemic stroke, give aspirin 300mg por 2 weeks
What should be suspected in a patient with focal weakness, numbness, tingling, limb ataxia, sudden loss or blurring of vision in one eye (optic neuritis), and how to diagnose it?
Multiple sclerosis.
Diagnosis: MRI spinal cord and brain
Treatment
- acute: IV or oral methylprednisolone
- Interferon-beta
What should be suspected in a patient with back pain radiating to legs, motor weakness with knee extension and foot dorsiflexion, and perineal sensory loss? How to treat it?
Causa equina syndrome: damage to the cauda equina causes loss of function of the nerve roots of the spinal canal below the termination of the spinal cord.
This is a neurological emergency that requires immediate referral and intervention, for surgical decompression
What are the names of the cranial nerves?
I olfactory (“one nose”)
II optic (“two eyes”)
III oculomotor (“moving three fingers in front of the face”)
IV trochlear (“quatro - troqueal”)
V trigeminal (“five fingers - mom + dad + triplets”)
VI abducens (“seis - abduCENte”)
VII facial (“sete = letra F = facial”)
VIII vestibulocochlear (“score 8 for the vestibular”)
IX glossopharyngeal (“nine is like the letter G”)
X vagus (“zero is a vague number”)
XI spinal accessory (“11 looks like an wardrobe accessory”)
XII hypoglossal (“12 = children = hypoglos”)
Alzheimer’s/Dementias and DLVA
Notify upon diagnosis.
Can keep driving until concerns arise, then patient should be advised to stop driving until a decision is made by the DVLA.
TIA and DVLA
Stop driving for 1 month after the incident.
Patients don’t need to inform DVA if they had an TIA and have recovered.
Stroke and DVLA
Stop driving for 1 month and resume driving if there is satisfactory clinical recovery.
DVLA only needs to be informed if there are residual neurological deficits 1 month after the episode.
DVT/PE and DVLA
Patient doesn’t need to inform DVLA.
There are no restrictions to driving as long as the patient didn’t lose counciousness and can move their legs freely.
When is the physician responsible for informing the DVLA?
When a patient was supposed to inform, but didn’t.
When a patient was supposed to stop driving, but didn’t.
How to distinguish between Alzheimer’s and NPH’s MRI?
Imaging that shows enlarged ventricles with obvious cortical atrophy - lean towards Alzheimer’s disease
Imaging that shows enlarged ventricles without obvious cortical atrophy - lean towards normal pressure hydrocephalus
clinical features agains NPH: absence of gait disturbance and sphincter comprimise
NPH = “wet, wobbly, wacky grandpa” (incontinence + gait disturbances + cognitive changes)
Name 5 diseases of autosomal recessive inheritance, 5 diseases of autosomal dominant inheritance, 2 diseases of X-linked dominant inheritance, and 5 diseases of X-linked recessive inheritance.
Autosomal recessive
1. cystic fibrosis
2. sickle cell anaemia
3. thalassemia
4. congenital adrenal hyperplasia
5. haemochromatosis
Autosomal dominant
1. huntingon
2. neurofibromatosis
3. PCKD
4. osteogenesis imperfecta
5. VWD
X-linked dominant
1. fragile X syndrome
2. alport’s syndrome
X-linked recessive
1. haemophilia
2. duchenne muscular atrophy
3. becker’s disease
4. G6PD deficiency
5. red-green colorblindness
What is the INR range target for most cases?
INR range 2-3
- prophylaxis or treatment of VTE
- reduction of the risk of systemic embolism for people with Afib and valvular heart disease
Only patients who underwent mechanical heart valve replacement with metallic valves require lifelong anticoagulation with target INR of 2.5 - 3.5
