Imaging Alzheimer's Disease Flashcards
What is a big risk factor for Alzheimer’s disease?
Age
What is Dementia?
Umbrella of the symptoms of memory impairment, behavioural aspect
What is the most common form of disease especially over 65?
Alzheimer’s
What happens to people under the age of 65?
The causes of dementia even out between early onset and genetic forms of Alzheimer’s and Frontal Temporal Dementia
What happens as you lose brain?
The ventricles expand to fill the space
What are the early places where typical Alzheimer’s disease is found?
Hippocampus and a lot of structures in the medial temporal lobe
What can imaging give?
A feature of cognitive decline of Dementia
What are the roles for imaging Alzheimer’s Disease?
- Diagnosis
- Differential Diagnosis
- Neuroscience
- Disease progression and modification
What is the diagnosis?
- Structural pathology (e.g. tumour)
- Normal vs pathological (non-specific): atrophy or white matter changes
- Predictive
What is neuroscience?
Understand the onset and evolution of degenerative dementias
What are the disease progression and modification?
- For clinical trials
- memory test
- cognitive test
- how are people functioning?
What did the patient William Utermohlen use?
Self-portraits to document his decline into dementia
He cannot function on a daily basis
What are the 3 large phase of the inexorable progress from a prolonged preclinical phase
- Pre-clinical
- Diagnosis
- Dementia
What is preclinical phase?
Try to identify the underlying pathology for symptoms that are occuring and try to clear that up
What is the diagnosis phase?
that it causes dysfunction and damage in the neurons to cell death – cause people to decline in memory symptoms, behavioural symptoms
What is full blown dementia?
Where people are unable to take care of themselves and global function is really impaired
What happens long before any transition into cognitive impairment?
There is a long slow build-up of amyloid plaque data that is visible on either CSF lumbar punctures or on PET
When is Tau detected?
Only after the amyloid
What does build up of pathology cause?
loss of brain cells and decrease in metabolism – poor functioning brain that continues to go up and that happens very proximal to when people start showing symptoms of mild cognitive impairments
• It doesn’t reach threshold to form diagnostic criteria and full-blown Alzheimer’s disease
What are the clinicopathological correlation stages of AD?
- Trans-entorhinal
- Limbic
- Neocortical
What is Trans-entorhinal?
A small portion of medial temporal lobe and that tends to go first with limbic, hippocampal, amygdala and medial temporal lobe structures
What is medial temporal lobe associated with?
Episodic memory
What can we rule out for the diagnosis of AD?
- Vitamin D deficiency
- Tumour
- Hypertension/vascular
mitigated by lifestyle factors
Why is Diagnosis of AD important?
- For patient and families
- To rule out other causes (space occupying lesion)
- To guide treatment and research