Neurology Final Flashcards
(61 cards)
What are is the mx of brain abscess? [3]
surgery
* a craniotomy is performed and the abscess cavity debrided
* the abscess may reform because the head is closed following abscess drainage.
IV antibiotics: IV 3rd-generation
* cephalosporin + metronidazole
intracranial pressure management:
* dexamethasone
Describe how you manage NPH [2+]
Shunt Surgery
- Ventriculoperitoneal shunting is the most common surgical intervention, with adjustable valve systems preferred due to their ability to regulate cerebrospinal fluid flow based on individual patient needs.
- First-line treatment in the acute setting is usually insertion of an external ventricular drain
- Regular monitoring post-surgery is important to detect complications such as infection, overdrainage, underdrainage, and mechanical shunt failure.
Non-Surgical Management
* While shunting is the primary treatment modality, non-surgical options may include lifestyle modifications such as avoiding medications that can exacerbate symptoms (e.g., sedatives, anticholinergics).
* Physiotherapy may be beneficial in managing gait disturbances.
What investigations do you conduct for MG [4]
Ztf:
.1. Antibody testing:
- AChR antibodies (around 85%)
- MuSK antibodies (less than 10%)
- LRP4 antibodies (less than 5%)
.2. A CT or MRI of the thymus gland is used to look for a thymoma.
.3. Edrophonium test:
- Patients are given intravenous edrophonium chloride
- Normally, cholinesterase enzymes in the neuromuscular junction break down acetylcholine. Edrophonium blocks these enzymes, reducing the breakdown of acetylcholine
- As a result, the level of acetylcholine at the neuromuscular junction rises, temporarily relieving the weakness.
- A positive result suggests a diagnosis of myasthenia gravis.
PM:
Repetitive nerve stimulation (RNS):
- repetitive electrical stimulation of a peripheral nerve while recording the compound muscle action potentials (CMAPs) from a target muscle.
- A decline in the amplitude of CMAPs after repetitive nerve stimulation, known as decrement, supports the diagnosis of MG.
Single-fiber electromyography (SFEMG):
- This is the most sensitive test for MG, which measures the variability in the time it takes for individual muscle fibres to respond to nerve stimulation (jitter) and the failure of some fibres to respond at all (blocking).
- Abnormal jitter and blocking are indicative of impaired neuromuscular transmission in MG.
NB:
- due to the potential side effects and limited specificity, edrophonium test has been largely replaced by more specific and sensitive diagnostic tests.
Describe 4 treatment options for MG [4]
Pyridostigmine is a cholinesterase inhibitor that prolongs the action of acetylcholine and improves symptoms. First-line
Immunosuppression (e.g., prednisolone or azathioprine) suppresses the production of antibodies
Thymectomy can improve symptoms, even in patients without a thymoma
Rituximab (a monoclonal antibody against B cells) is considered where other treatments fail
Intravenous immunoglobulin (IVIg) or plasma exchange may be considered in severe cases or during myasthenic crisis.
How do you investigate for LES? [1]
EMG
- incremental response to repetitive electrical stimulation
How do you differentiate LES vs MG? [3]
Clinically, LES typically presents with proximal muscle weakness that improves with repeated use (unlike MG where symptoms worsen with use).
Autonomic symptoms such as dry mouth or impotence are common in LES but rare in MG.
Ophthalmoplegia and bulbar symptoms are less common in LES compared to MG.
Management of Myasthenic Crisis? [2]
In a myasthenic crisis, immediate hospitalisation is required.
Intensive respiratory support may be necessary, including intubation and mechanical ventilation if there is impending respiratory failure.
Rapid short-term symptom control can be achieved by plasma exchange or IVIg.
In MG Resp. crisis - what investigation would you do and how would this inform your mx plan? [2]
Assessment: BEDSIDE SPIROMETRY - FVC (not peak flow/FEV1):
- >20ml/kg (1.5-2.0L) – on repeated measures – ABG and Rapid response/anaesthetic review – consideration of HDU/ITU
- >15ml/kg (1L) – urgent Rapid response/anaesthetic review and ITU transfer
With Horners, anhydrosis determines the site of the lesion. The causes can be remembered as the 4 Ss, 4 Ts and 4 Cs.
Describe the causes of these lesions [+]
Central lesions (4 Ss):
* S – Stroke
* S – Multiple Sclerosis
* S – Swelling (tumours)
* S – Syringomyelia (cyst in the spinal cord)
Pre-ganglionic lesions (4 Ts):
* T – Tumour (Pancoast’s tumour)
* T – Trauma
* T – Thyroidectomy
* T – Top rib (a cervical rib growing above the first rib above the clavicle)
Post-ganglionic lesion (4 Cs):
* C – Carotid aneurysm
* C – Carotid artery dissection
* C – Cavernous sinus thrombosis
* C – Cluster headache
Describe a key test / feature of early stage frontotemporal dementia? [1]
Constructional apraxia i.e. failure to draw interlocking pentagons may be a key feature in the early stages
Describe how epilepsy can be classified based on epilepsy syndromes [4]
An epilepsy syndrome is determined by a group of features observed together, such as the type of seizure, age of onset, EEG findings, and often prognosis. E.g:
Childhood Absence Epilepsy (CAE):
- Characterised by typical absence seizures, with onset usually between 4-10 years.
Juvenile Myoclonic Epilepsy (JME):
- Marked by myoclonic jerks, typically shortly after waking.
Dravet Syndrome:
- Severe epilepsy beginning in infancy, initially presenting as prolonged seizures with fever.
Lennox-Gastaut Syndrome:
- Characterised by multiple seizure types, cognitive dysfunction, and a specific EEG pattern.
abscence seizures are associated with which findings on EEG? [1]
3hz spikes on EEG
Describe the notable side effects of:
- Sodium Valproate [4]
- Carbamazepine [3]
Sodium Valproate:
* Teratogenic, so patients need careful advice about contraception
* Liver damage and hepatitis
* Hair loss
* Tremor
Carbamazepine:
* Agranulocytosis
* Aplastic anaemia
* Induces the P450 system so there are many drug interactions
What are notable side effects of:
- Phenytoin [3]
- Ethosuximide [2]
Phenytoin
* Folate and vitamin D deficiency
* Megaloblastic anaemia (folate deficiency)
* Osteomalacia (vitamin D deficiency)
Ethosuximide
* Night terrors
* Rashes
Which of the following can cause secondary angle closure glaucoma
Carbamazepine
Lamotrigine
Levetiracetam
Sodium valproate
Topiramate
Which of the following can cause secondary angle closure glaucoma
Carbamazepine
Lamotrigine
Levetiracetam
Sodium valproate
Topiramate
What are treatment options for IESS? [3]
Steroids
Vigabatrin
+/- ACTH
Describe what is meant by self-limited epilepsy with centrotemporal spikes (SeLECTS)
Describe the presentation
Describe the EEG
Presentation:
- 4-10 years old
- Focal seizures are brief, typically < 2/3 mins, few from sleep, associated with somatosensory symptoms
EEG:
- High amplitude centrotemporal sharp and slow wave complexes
Lecture
What is important to know aboout acute ( < 48 hr metabolic / toxic) ir ( < 7 days stuctural), remote ( > 7days from brain insult) with regards relationship with reoccurence and to epilepsy? [2]
Lecture:
- Behavioural changes are common with which drug? [1]
Levetiracetam
The patient’s presentation of peripheral neuropathy, lymphadenopathy, and bleeding gums suggests that he has been taking which anti-epileptic? [1]
The patient’s presentation of peripheral neuropathy, lymphadenopathy, and bleeding gums suggests that he has been taking phenytoin
It is useful when thinking about the management of epilepsy to consider certain groups of patients.
Which patients are have special considerations and how do you manage these? [3]
patients who drive:
- generally patients cannot drive for 6 months following a seizure.
- For patients with established epilepsy they must be fit free for 12 months before being able to drive
patients taking other medications:
- antiepileptics can induce/inhibit the P450 system resulting in varied metabolism of other medications, for example warfarin
women wishing to get pregnant:
- antiepileptics are generally teratogenic, particularly sodium valproate.
- It is important that women take advice from a neurologist prior to becoming pregnant, to ensure they are on the most suitable antiepileptic medication.
- Breastfeeding is generally considered safe for mothers taking antiepileptics with the possible exception of the barbiturates
women taking contraception:
- both the effect of the contraceptive on the effectiveness of the anti-epileptic medication and the effect of the anti-epileptic on the effectiveness of the contraceptive need to be considered
Describe the clinical features of ataxic telangiectasia [4]
cerebellar ataxia
telangiectasia (spider angiomas)
IgA deficiency resulting in recurrent chest infections
10% risk of developing malignancy, lymphoma or leukaemia, but also non-lymphoid tumours
Describe the differences betwen Freidrich’s ataxia and ataxic telangiectasia? [+]
FA:
- HOCM
- DM
- Onset at 10/15 yrs
- Optic atrophy
- Kyphoscoliosis
AT:
- Telangiectasia
- IgA deficiency –> recurrent chest infections
- Increased risk of leukaemia and lymphoma
- Onset at 1-5
NB: both autosomal recessive; cerebellar ataxia and onset in childhood
