Session 9: Cortical Dysfunction Flashcards
What is Dementia?
- Progressive deterioration of higher cortical function.
- Dementia overall results in neuronal degeneration throughout the cortex which accounts for its wide variety of symptoms and clinical picture.
What is the presentation of dementia generally?
- Memory Deficit: struggle to learn new information, short term memory loss
- Behavioural: altered personality, disinhibition, labile emotions, wandering
- Physical: incontinence, reduced oral intake, difficulty swallowing
- Language disorder: anomic aphasia, difficulty understanding language
- Visuospatial disorder: unable to identify visual and spatial relationships between objects
- Apraxia: difficulty with motor planning resulting in inability to perform learned purposeful movements
What investigations are done for Dementia?
- Full history + MMSE (assess the degree of cognitive impairment and rate of progression of disease)
- Full neurological examination
- Blood Test
- CT/MRI head (rule out other causes such as tumour and check for features of dementia)
- Memory Clinic follow up
What are features of dementia on CT/MRI head?
- Dilatation
- Generalised Atrophy
- Hippocampal Atrophy
What does a CAM Score assess?
- Acute change or fluctuating mental status
- Altered consciousness – hypo (refusing food or drink) /hyperactive (rambling)
- Inattention
- Disorganised thinking
What CAM score describe delirium?
Combination of 1+2 and either 3 or 4 shows Delirium
What are the common non reversible causes of Dementia?
- Alzheimer’s Disease (commonest cause of dementia. Account for 60-80% of cases)
- Dementia with Lewy-Bodies
- Fronto-temporal Dementia
- Vascular Dementia
- Crutzfeldt-Jacob disease
What are the common reversible causes of Dementia?
- Depression
- Trauma
- Vitamin Deficiency
- Alcohol
- Thyroid Disorder
What is the macroscopic pathology of Alzheimer’s disease?
-Loss of cortical and subcortical white matter causing gyri atrophy with narrow gyri and wide sulci along with mark ventricular dilation reflecting loss of white matter
What is the microscopic pathology of Alzheimers disease?
Formation of
- Amyloid-beta plaques (proteolytic break down from amyloid precursor protein)
- Neurofibrillary tangles
Causes degeneration
What is the Clinical picture of Alzheimer’s disease?
- Starts with minor memory loss which may not be initially noticed or impact on their life
- Progression to development of problems with visuospatial awareness and apraxia making it difficult to carry out daily tasks such as getting dressed and cooking.
- In Alzheimer’s disease, there is a slowly linear decline over many years with no recovery, until the patient is incontinent, unable to recognize loved ones and loses a sense of self
What is the microcopid pathology of Dementia with Lewy bodies?
-Lewy Bodies in the cortex and Substantia nigra
What is the clinical picture of Dementia with Lewy bodies?
- Substantial fluctuating decline in cognition over time which may improve for a while and then drop back down.
- Parkinson’s symptoms (Bradykinesia, Tremor, Rigidity, Postural instability resulting in falls, Visual hallucination)
- Unresponsive to dopamine agonist treatment in the same way Parkinson’s disease would be
What is the pathology involved in Vascular Dementia?
- Arteriosclerosis of the blood vessels supplying the brain
- Diffuse small vessel disease vs infarcts (large vessel disease)
What is the clinical picture in Vascular Dementia?
- Abrupt, step wise decline in cognitive function related to vascular episode.
- Following insult, the patient will retain that current level of cognition until another episode occurs.
What is the management of Vascular Dementia?
-Assess cardiovascular risk and treat hypertension/high cholesterol
What are the pathologies associated with Fronto-tempoal dementia?
- Frontotemporal lobar degeneration with tau pathology
- Pick’s disease
- Familial tauopathies
How is Dementia Holistically managed?
- Therapies
- Pets, Babies - Memory aids
- Orientation boards, Remembrance Therapy, Life stories - Social care
- Risk Assessment, Care Needs, Mental Capacity Act
- More important to manage the social implications and concerns of the family.
- Need to make sure the patient is safe and act in their best interest which may require care at home or a permanent nursing home placement - Drugs
- Cholinesterase inhibitors(group of drugs shown to slow progress of disease temporarily in some patients with mild-moderate Alzheimer’s but this is only temporary)
- Memantine
What is a seizure?
-A sudden irregular discharge of electrical activity in the brain causing a physical manifestation such as sensory disturbance, unconsciousness or convulsion.
What is a convulsion?
-Uncontrolled shaking movements of the body due to rapid and repeated contraction and relaxation of muscles
What is an aura?
A perpetual disturbance experienced by some prior to a seizure e.g. strange light, unpleasant smell, confusing thoughts
What is epilepsy?
Neurological disorder marked by sudden recurrent episodes of sensory disturbance, LOC or convulsions, associated with abnormal electrical activity in the brain
What is Status Epilepticus?
- Epileptic seizures occurring continuously without recovery of consciousness in between
- Medical emergency
What are the types of Partial Seizures?
- Simple (same consciousness)
- Complex (consciousness is impaired)
What are the types of Generalised Seizures?
- Absence (daydreaming)
- Myoclonic (brief shock-like muscle jerks)
- Tonic clonic (1st tonic so muscles tense, 2nd clonic convulsions)
- Tonic (increased tone)
- Atonic (without tone so drip attacks occur)
What are common examples of partial seizures?
- Temporal lobe epilepsy – 1st/2nd decade in most following seizure with fever or an early injury to the brain
- Aura e.g. auditory hallucination, rush of memories
- Frontal lobe epilepsy
- Abnormal movement when motor area affected
What are the investigations done in epilepsy?
- Clinical history
- EEG
- MRI (all patients with new-onset seizures)
- ECG (in all adults)
Why is EEG used in Epilepsy?
- Not diagnostic but supports the diagnosis
- Assess risk of seizure recurrence in there first unprovoked seizure
- Standard assessment involves photic stimulation and hyperventilation and patient has to be warned that may induce a seizure
When shouldn’t you use EEG?
- Probably syncope
- Clinical presentation support diagnosis of non-epileptic event
- In isolation to make epilepsy diagnosis
What should you do if EEG is unclear?
- Repeat standard EEGs
- Sleep EEGs
- Long term video or ambulatory EEG
What part of the history before the seizure are you concerned about?
- PMH, FH
- Triggers
- Aura
- First sign/symptom
What part of the history during the seizure are you concerned about?
- Description of Seizure
- Duration
- Abrupt/gradual end
What part of the history after the seizure are you concerned about?
- Post ictal state
- Tongue biting
- Incontinence
- Neurological deficit
What are differential diagnosis for Epilepsy?
- Vascular: Stroke, TIA
- Infection: Abscess, Meningitis
- Trauma: Intracerebral haemorrhage
- Autoimmune: Systemic Lupus Erythematous
- Metabolic: Hypoxia, Electrolyte imbalance, Hypoglycaemia, Thyroid dysfunction
- Iatrogenic: Drugs, Alcohol Withdrawal
- Neoplastic: Intracerebral mass
-Congenital
What is the management of Epilepsy?
- Lorazepam
- Midazolam
What has to be considered with epilepsy and driving?
- If suffers epilepsy when awake, licence is taken away until 1-year seizure-free
- If due to medication change: 6 months seizure-free
- Seizures whilst asleep or don’t affect driving or consciousness – assessment of case by DVLA
- If one-off seizure, then can apply when 6 months seizure-free and assessment by DVLA
