Hi,
    Embedding is one of my pet peeves. If a piece of tissue is embedded
horizontally or vertically there will inevitably be compression. Horizontally
because the knife is hitting the tissue all at once. Kind of like a diver landing
spread eagle into the water. Vertically because the tissue will compress into
itself rather than being supported by the paraffin. when the tissue is embedded
at an angle (45 degrees optimally) the blade eases into the tissue a little at a
time while being supported by the paraffin.
    When you cut into a steak you will probably notice that you lift the knife
some to start the cut. The same is true of sectioning. In the case of a grosser
that stuffs too much into the cassette, my best advise is to kick them, hard (the
shin will do just fine but creativity is encouraged).
just my rant ... sorry
Amos Brooks

Connie McManus wrote:

> Gee, John, you go through a lot to embed.  I don't worry so much about what
> angle to place the tissue  on the horizontal plane.  As a general rule, I
> embed cut side down, tubes show the entire lumen, tissue with layers (like
> gut) are embedded on edge so that all layers are visible in the stained
> section.  Skin is oriented the way you mentioned so the hair doesn't rip
> the tissue. Also, my pathologists tend to cram a lot of tissue into the
> cassette when they trim in the tissues. If it's too much to cut and
> maintain my sanity, I split the tissue to make more blocks.
>
> Well that's my $0.02 worth.
>
> Connie McManus
> Veterinary Diagnostics Lab
> Utah State University
> Logan, UT
> USA
>
> At 03:01 PM 05/08/2000 -0400, Mackinnon, John wrote:
> >I know that there was some discussion recently about proper embedding
> >techniques but what I am looking for is comments from people out there and
> >how they do things.
> >
> >I know that I was taught to line my skins up horizontally (can be slightly
> >angled) with the dermal layer to the top and being the last part the knife
> >cuts through.  Things like uterus slightly angled to make cutting easier and
> >tubular multiple tubular structures lined up horizontally etc.  I was also
> >told that you should place your larger rectangular blocks horizontally since
> >this gives you the shortest distance through the wax and less compression
> >and less chance for wrinkles in tissue sections.  Well that is my two cents
> >worth now lets hear yours.  (especially those doing a lot of derm path)
> >
> >Thanks in advance,
> >
> >John MacKinnon MLT, ART
> >Senior Technologist, Pathology
> >Lakeridge Health Oshawa
> >Ontario, Canada
> >
> >
> >