Histopatholgy and Cytopatholgy Flashcards
what is the use of Biopsies?
check for normality
inflammation
cancer and type
what is the turnaround for biopsy?
2-3 days
what is the use of resection specimens?
check for metastases
what is the turnaround for resection specimens (not emergency, use for study)?
5-7 days
what is the use of frozen sections?
done by histopathologist
done rapidly during surgery for quick diagnosis for
example:cancer incision surgery
what is the turnaround of frozen sections?
20-30 minutes
what is the difference between a hospital post-mortem and a coroner’s post mortem?
family give permission
state ordered with no family permission required
how are sections obtained and used?
o Obtaining – fixed in formalin and embedded in paraffin wax – thin slices can then be cut.
o Use – we can STAIN them, identify specific ANTIGENS (using antibodies) and carry out molecular tests.
what work is done in cytopathology?
done on cells
o Smears – such as cervical screening.
o Fine-needle aspirations (FNA).
cytopathology
diagnosis made on cells (therefore less invasive)
- specimens
- sputum
- body fluids
- cervical smears
- fine needle aspirates
what must be used to “fix” specimens for histopathology ?
formalin
stabilises protein bonds to prevent autolysis
when will large specimens reach the clinician?
2-3 days
take into account fixation (longer for large or fatty)
when will small specimens reach the clinician?
24 hours
when is a specimen needing rapid diagnosis returned to the clinician?
4-5 hours to rapid process
when is a frozen section used?
for very rapid processing e.g. mid-surgery
- no fixative added
- small sample selected and frozen rapidly
- fixed rapidly and stained with haemotoxylin and eosin
- response in 20 minutes
what colour do haemotoxylin and eosin colour components of the cells?
haemotoxylin stain the nuclei blue
eosin stains the cytoplasm pink
what must be done to tissue before impregnating them with paraffin?
dehydrate with alcohols
what can be identified with nitrate solution?
- melanin pigment
- fungi
- calcium deposits
- fibres
which bacteria can be identified with Ziehl-Nielsen method?
tuberculosis bacilli
what are cervical smears stained with?
Papanicolaou
permanently preserved
