One micrometer sections (was; microm microtome)

<< Previous Message | Next Message >>
From:Tim Morken <> (by way of histonet)
To:histonet <>
Content-Type:text/plain; charset="us-ascii"

It is possible to cut sections with the microtome set at the one
micrometer setting, but it's hard to prove that they are actually one
micrometer in thickness.

At the last lab I worked at we did 1um sections on kidney biopsies and
used Paraplast Plus paraffin to infiltrate and Surgipath paraffin to
embed. The block was faced, iced and then sectioned. The block was not
taken off the chuck when sections started wrinkling. Instead ice wrapped
in guaze was put on the block face and held there with rubberbands for a
few minutes. This way you didn't have to re-face the block at all. We
had 7 technologists who did this using a Zeiss 1512 microtome with
disposable blades. Some we more adept at getting sectins than others,
but all were able to do it.

I felt it was a waste of time and effort considering that EM was also
done (as is usual in renal cases) and the sectons obtained there would
give much higher quality information than the paraffin sections. The
renal pathologist, however, insisted he needed those thin sections from

In another lab I worked at we cut 3 um sections in paraffin and also did
EM. The renal pathologist there felt that was just fine.

Having started in EM I always felt that the whole kidney biopsy should
be done in EM resin. I have the work of Theresa Flores in Louisiana to
thank for helping me convince my pathologist to give it a try, using her

Tim Morken, B.A., EMT(MSA), HTL(ASCP)
Infectious Disease Pathology
Centers for Disease Control
1600 Clifton Rd.
Atlanta, GA 30333


FAX:  (404)639-3043

----Original Message Follows----
Date: Tue, 02 Mar 1999 22:33:47 -0500
From: (Evanne Maher)
Subject: Re: Microm Microtome
To: 'Histonet' <>,
 "Brody;Juanita X" <>

     There is no way you will get 1 micron sections off of a paraffin
     block.  That's why people use plastic embedding for thin sections.
     The microtome will advance 1 micron but the paraffin is too soft to
     hold up to this small advance.  It is also just about impossible to
     cut 1 micron frozen sections and they are much harder.  If you want
     cut at that setting, you need to embed in plastic, and this
     will perform well.

______________________________ Reply Separator
Subject: Microm Microtome
Author:  "Brody;Juanita X" <> at Internet
Date:    2/26/99 2:34 PM

We purchased a motorized microtome, Zeiss HM355, to cut 1 micron thick
paraffin sections of renal biopsies.   We use low profile blades and
been unable to cut thin sections as required by the pathologist.   Does
one have experience cutting thin sections on this microtome?

Get Your Private, Free Email at

<< Previous Message | Next Message >>