Neurology Flashcards
Posterior communicating artery aneurysm signs
Occulomotor CN III Palsy - Ptosis, Mydriasis (dilated) and ‘Down and Out’ due to unopposed SO an LR muscles.
Cavernous Sinus Syndrome
CN III palsy + absent corneal reflex + proptosis
EACDIT Syringomelia
E: Rare. Incidental finding.
A: Syrinx (fluid-filled cavity with spinal cord).
C:‘Cape like’ loss of pain and temperature (spinothalamic tracts), with preserved light touch, proprioception and vibration (dorsal column).
Due to crossing of tracts in anterior commissure (first affected)
Ix: MRI with contrast to exclude tumour/tethered cord. Brain MRI to exclude chiari malformation.
Tx: Surgical - FMD, shunt if sumptomatic.
Ascending Spinal Cord Tracts and their function/path
Dorsal Column (Fasiculus gracilis & cuneatus)
Anterolateral Spinothalamic
Spinocerebellar
Dorsal Column: Fine touch, vibration & proprioception. Fasiculus gracilis (lower limbs), Fasiculus cuneatus (upper limbs). Ipsilateral.
Anterolateral Spinothalamic: Crude touch (pressure), pain & temperature. Contralateral: decussate early on (1-2 segments before crossing - lissauer).
Spinocerebellar: proprioception to cerebellum.
Descending Spinal Cord Tracts and their function/path
Corticospinal
Lateral Rubrospinal
Medial Reticulospinal
Vestibulospinal
Tectospinal
Corticospinal: voluntary movements of limbs. Contralateral: decussate in midbrain.
Lateral Rubrospinal: Fine motor control
Medial Reticulospinal: facilitates contraction, increases tone
Vestibulospinal: Balanace and posture
Tectospinal: head and vision co-ordination
UMN (Pyramidal Tract) Signs
Hyper-reflexia (loss of inhibitory signals; increased DTRs)
Hypertonia (increased tone)
Spastic Paresis (weakness)
Basbiski +ve
Clasp-knife rigidity
LMN Signs
Hypo-reflexia (absent DTRs)
Hypotonia (reduced tone)
Atrophy (muscle wasting)
Babinski negative
Fasciculations/Fibrillation
Difference in presenation of UMN vs LMN when face is affected
UMN - forehead sparing
LMN - forehead involvement
Due to Cortical nerve tract innervation (facial nerve) supplying forehead
Bell’s Palsy vs Ramsay Hunt and Management
Both present with facial nerve (CN VII) palsy.
Bell’s Palsy - No rash. Usually HSV.
Ramsay Hunt - Vesicular rash present (ears). Usually VZV.
Tx: Antivirals & Steroids (Pred.) within 72hrs (3d) of symptoms. Eyecare - lubricating eye drops to prevent keratitis.
Motor Neuron Disease EACDIT
E: >40 years
A: Unknown cause. 50% causes by Amyotrophic lateral sclerosis (LMN in arms and UMN in legs). Other forms exist.
C: UMN and LMN signs.
Ix: Clinical signs/symptoms
Tx: Riluzole (inhibits glutamate), prolongs life by 3m. Respiratory care: NIV (BIPAP) at night. 50% patients die within 3 years.
Multiple Sclerosis EACDIT
E:
A:
C:
Ix:
Tx:
Types of Focal (Partial) Seizure and their clinical features
Localsied to one hemisphere of the brain
Aware (simple) - alert & remembers (preserved conciousness).
Unaware (complex) - loses awareness, no recollection.
Motor symptoms - twitching, muscle jerking
Non-motor - Senory; auditory, tactile, olfactory. Psychological. Autonomic.
Jacksonian March - motor symptoms which spread.
Automatisms - lip smacking, rubbing hands, chewing, swallowing, unpurposeful walking
Types of Generalised Seizure and their clinical features
Motor - Tonic, Clonic, Tonic-clonic, Atonic, Myoclonic
Non-motor - Absence (staring, ‘spaced-out’).
Tonic-Clonic (Grand Mal): tonic phase; muscle stiffen/rigidity. clonic phase; muscles rapidly contract then relax, convulsions.
Atonic - sudden muscle relaxation ‘drop-attack’, ‘tree-log’
Myoclonic - involuntary muscle jerks confined to limbs/face
Postictal state - confusion, drowsiness, sleepy, amnesia for hours
Todd’s paralysis/paresis - hemiparesis which lasts 15hrs
Status Epilepticus features and management
Definition: prolonged convulsive seizure lasting for 5 minutes or longer, or recurrent seizures one after the other (2 within 5 minute) without recovery in between.
Management:
- ABC - airway adjunct, oxygen and check glucose
- Buccal midazolam as first-line treatment in the community.
- Rectal diazepam if preferred, or if buccal midazolam is not available.
- Intravenous lorazepam if intravenous access is already established and resuscitation facilities are available. Can be repeated once after 10-20 minutes.
- If ongoing (or ‘established’) status it is appropriate to start a second-line agent such as phenytoin or phenobarbital infusion
- If no response (‘refractory status’) within 45 minutes from onset, then the best way to achieve rapid control of seizure activity is induction of general anaesthesia.
Note that midazolam oromucosal solution is not licensed for children under 3 months or adults over 18 years of age (for infants between 3–6 months of age treatment should be in a hospital setting); and some preparations of rectal diazepam are not licensed for children under 1 year of age.
Call an ambulance for urgent hospital admission if seizures do not respond promptly to treatment.
Call an ambulance for urgent hospital admission if seizures do respond to treatment but:
- Seizures were prolonged or recurrent before treatment was given, particularly if seizures had developed into status epilepticus.
- There is a high risk of recurrence, such as a history of repeated seizures or status epilepticus.
- There are difficulties monitoring the person’s condition.
- This is their first seizure.
Seizure Definition
- Transient occurrence of signs or symptoms due to abnormal excessive or synchronous neuronal activity in the brain [Fisher et al, 2017]. Seizures can manifest as a disturbance of consciousness, behaviour, cognition, emotion, motor function, or sensation [Krishnamurthy, 2016; Fisher et al, 2017].
- An isolated seizure can be caused by toxic, metabolic, structural, and infectious factors and should not be confused with epilepsy [Krishnamurthy, 2016].
Epilepsy Definition
Epilepsy is a neurological disorder in which a person experiences recurring seizures [NICE, 2012]. The International League Against Epilepsy describes epilepsy as a disease of the brain defined by any of the following conditions [Fisher et al, 2014]:
- At least two unprovoked seizures occurring more than 24 hours apart.
- One unprovoked seizure and a probability of further seizures similar to the general recurrence risk (at least 60%) after two unprovoked seizures, occurring over the next 10 years.
- Diagnosis of an epilepsy syndrome.
Childhood Epilepsy Syndromes
Infantile Spasms (West’s Syndrome) - first few months; ‘Salaam’ attacks, mental handicap, poor prognosis.
Lennox-Gastaut Syndrome - 1-5 years, moderate-severe mental handicap
Benign Rolandic Epilepsy - parasthesia of face on waking
Juvenile Myoclonic Epilepsy - Teenage girls; infrequent generalised seizures in the morning
The following is a mnemonic for Lennox-Gastaut Syndrome:
L: Little kids (age of onset 1-5 years old)
G:Grades diminishing (intellectual disability/ developmental delay after first seizure)
S: Slow Spike wave EEG formation
Febrile Seizure EACDIT
E: A febrile seizure is generally accepted to be a seizure accompanied by fever (temperature more than 38°C by any method), without central nervous system infection, which occurs in infants and children aged 6 months to 6 years. Commonest form of childhood seizure up to the age of 2 years.
A: Secondary to fever. Identifying red flag symptoms and signs suggesting a serious or life-threatening cause such as meningitis/meningococcal disease or encephalitis, and managing this appropriately.
C: Simple; tonic-clonic <15 minutes, complete recovery within 1hr. Complex: partial (focal) seizure (movement limited to one side of the body or one limb); > 15 minutes; recurrence within 24 hrs or within the same febrile illness; or incomplete recovery within 1 hour.
Ix: Identifying red flag symptoms/underlying cause of fever, where possible. Asking about fever onset, peak temperature, duration, and relationship to the seizure. Asking about the seizure and any post-ictal drowsiness. Asking about previous seizure episodes and any family history of febrile seizures or epilepsy. Assessing the child’s temperature, consciousness level, any focal neurological deficit, fluid status, and signs of an alternative cause of seizure.
Tx:
If tonic-clonic movements last for more than 5 minutes:
- Call an emergency ambulance, or
- Give emergency benzodiazepine rescue medication if this has been advised by a specialist for a child with recurrent febrile seizures.
- Options are buccal midazolam or rectal diazepam (both drugs may be repeated once after 10 minutes if the seizure has not stopped).
Call an emergency ambulance if, 10 minutes after the first dose of rescue medication:
- The seizure has not stopped.
- The child has ongoing twitching (although the larger jerking movements may have stopped).
- Another seizure has begun before the child regains consciousness.
General management of Seizures
- sodium valproate is used first-line for patients with generalised seizures
- carbamazepine is used first-line for patients with focal seizures
