Intro To Pathology Flashcards
What is a disease?
A pathological condition of a body part, an organ or system characterised by an identifiable group of signs or symptoms
What is pathology?
The study of disease and cellular dysfunction
What is the importance of microscopic diagnosis? (2)
Definitive diagnosis
Guides the extent and type of surgery
Why are histopathologists useful when diagnosing a patient?
They can give information which influence decisions on further treatment and management
What is Mohs surgery?
Real time pathology, it is looking at a piece of tissue taken from someone and deciding whether the excision is complete or more needs to be removed. It is done using frozen sections
How can pathology help with treatment determining?
It can be used to suggest the likely efficacy of further treatments
How is the likely efficacy of further treatments calculated using pathology?
Use immuno-histochemisty to determine the presence of receptors specific to specific drugs
(Important because you don’t want to give someone a drug with lots of side effects unless you are confident it will actually do some good)
How do you prevent the issue of autolysis?
Treating tissues with fixatives
What do fixatives do?
Inactivate tissue enzymes and denature proteins
Prevent bacterial growth
Harden tissue (make it easier to cut)
What is used for fixation?
Formalin
How are the right bits of tissues taken from a sample?
Ask a pathologist!
Why do tissue samples need to be small?
- to fit in cassettes
- so they can be infiltrated by chemicals
How and why are the tissue samples hardened?
Paraffin wax
To make it easier to slice thinly
What must be done prior to hardening tissue samples?
Remove the water
How is water removed from tissue samples?
- dehydration using alcohol in vacuum (draws water out of cells)
- replace alcohol with xylene (can mix with wax)
- replace xylene with paraffin wax (molten)
