MICROTOMY Flashcards
previously processed tissue / tissue block is trimmed and cut into uniformly thin slices or sections
Microtomy
principle of microtomy
a spring balanced teeth or pawl is brought into contact with, and turns a ratchet feed wheel connected to a micrometer screw, which is in turn rotated, moving the tissue block at a predetermined distance towards the knife for cutting sections at uniform thickness
when was rocking (cambridge) microtome invented
1881
who invented the rocking (cambridge) microtome
Paldwell Trefall
- the simplest type of microtome for small and large paraffin-embedded blocks
rocking microtome
thickness of rocking microtome
10-12u
one of its disadvantage is, it will not form serial sections
rocking microtome
part of the rocking microtome that carries the block holder
upper arm
part of the rocking microtome that supports the column
lower arm
commonly used microtome for paraffin-embedded sections
rotary microtome
allows production of excellent serial sections
rotary
heavier and more stable microtome with up and down vertical movement which results to perfectly flat planes
rotary
who invented the rotary m
minot
when was the rotary microtome invented
1885-86
thickness of rotary m
4-6u
2 types of sliding m
- standard sliding
- base-sledge
the thickness of sliding m
4-9u
who invented the sliding m
Adams
when was the sliding m invented?
1789
sliding m that consists of 2 movable pillars holding the adjustment knife clamps for hard tissues and large blocks
base sledge
sliding m that is prone to danger
standard sliding
block remains stationary, the microtome moves in a forward and back motion
standard sliding
for hard and tough tissue blocks in all forms of media
base-sledge
for electrom microscope
ultra thin microtome
thickness of ultra-thin m
0.5u
uses fragments of broken plate glass
ultrathin microtome
who invented the freezing microtome
Queckett
when was the freezing microtome invented
1848
for undehydrated tissues in frozen state
freezing microtome
for rapid diagnosis and for fats and tissue constituents that may be damaged
freezing microtome
thickness of freezing m
10-15u
source of cold temp for freezing microtome
carbon dioxide
sections to be focused under compound microtome
- plane-concave
- plane-wedge
- biconcave