MICROTOMY

the process by which processed tissue that has been fixated, dehydrated, and cleared is trimmed and cut into uniformly thin slices.

(a)  

instrument that is capable of cutting a section at a predetermined thickness. “Depende sa gusto ni Pathologist.”

(a)  

The part where the tissue is held in position

• Block Holder (chuck)

• Knife Carrier and Knife

• Pawl, Ratchet Feed Wheel and Adjustment screws

It is used for actual cutting of tissue sections.

• Block Holder (chuck)

•  Knife Carrier and Knife

• Pawl, Ratchet Feed Wheel and Adjustment screws

This is to line up the tissue block in proper position with the knife.

• Pawl, Ratchet Feed Wheel and Adjustment screws

• Knife Carrier and Knife

• Block Holder (chuck)

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.

• TRUE

• FALSE

It is used for cutting serial sections of large blocks of paraffinembedded tissues

• Rocking Microtome (Cambridge)

• Rotary Microtome (Minot)

• Freezing Microtome (Cold Knife)

• Sliding Microtome

Invented by Paldwell Trefall in 1881 

It is the simplest and oldest type of microtome.

• . Sliding Microtome

• Freezing Microtome (Cold Knife)

• Rotary Microtome (Minot)

• Rocking Microtome (Cambridge)

In here, the knife is fixed or stationary and it is the block of the tissue that moves through an arc.

• Freezing Microtome (Cold Knife)

• Rocking Microtome (Cambridge)

• Sliding Microtome

Commonly, a section is cut as the tissue passes the knife edge in a slightly curved plane in 10-12 micrometers thickness

• Rotary Microtome (Minot)

• Rocking Microtome (Cambridge)

• Cryostat (Cold Microtome)