Re: GI biopsy blues

From:Bryan Hewlett

I'll just add the following to the very valid comments of Joyce and Patsy.
It is true that, with some wax formulations, too rapid a cooling can seem to
affect the plasticity of the wax. Which, after storage of the blocks at
warmer temperatures appears to restore itself. It is also true that, trace
amounts of clearing agent in the wax may give a softer consistency to the
block on initial cutting, while after a time in storage evaporation from the
surface removes these traces of clearant and the block will now have a
harder consistency on recutting.
That said, we have seen the artefact on recuts for special stains taken the
next day. We have also seen it on sections taken over a year later for
research purposes.
As I said before, slow recutting cures it!

We have been present during rapid cutting of GI section ribbons, stepped in
for demonstration purposes, and finished the ribbon the tech was cutting.
After mounting and staining sections from the leading and trailing portions
of the ribbon, the leading sections(i.e.rapid cuts) showed chattering, the
trailing sections didn't.
Over the years, we've had our share of  pathologists and techs alike, who
doubt this explanation for the cause of this very frustrating artefact.
The following demonstration has usually stemmed objections. Recut a block
which has shown the artefact, after cutting a ribbon rapidly, mount and
stain two or three sections. Cut a second ribbon very slowly, mount and
stain, compare.

Finally, to Patsy.
I enjoyed the description of your visit to the UK. It brought back many
memories. I was born and trained in Nottingham(Queen's was being built as I
left) and spent many hours walking the peak district.Used to go climbing in
 I must also admit to enjoying a pint or ten at the "Trip".



Bryan R. Hewlett
Technical Specialist
Department of Anatomical Pathology
Hamilton Regional Laboratory Medicine Program.
Ontario, Canada
----- Original Message -----
From: "rueggp" 
To: "Weems, Joyce" 
Cc: "'Bryan Hewlett'" ; ;

Sent: Thursday, April 25, 2002 3:50 PM
Subject: Re: GI biopsy blues

> Joyce is right about polymers hardening with time and heat.  Cold can
> inhibit polymerization, heat can accelerate polymerization, which may
> why putting your block into the heated water bath works better than
> sometimes.
> Patsy
> "Weems, Joyce" wrote:
> > Let me say this about recutting later......I discussed this with Ada
> > of Anatech several years ago. It would seem that the polymers harden
> > with time than with cold, therefore allowing for better sections later.
> > don't have to cut slowly for the recuts - just whack them off and most
> > likely they'll be ok.
> >
> > I have found this to be one of the most frustrating of artifacts ever to
> > deal with!
> >
> > Another thing I found good was putting the block in the warm water bath
> > a few seconds, then cooling and sectioning. The warm water seemed to
> > wonders. The slow...... steady turning of the microtome is essential for
> > first cuts of these creatures, tho.
> >
> > My 2 cents! j:>)
> >
> > Joyce Weems
> > Pathology Manager
> > Saint Joseph's Hospital of Atlanta
> >
> >         -----Original Message-----
> >         From:   Bryan Hewlett []
> >         Sent:   Thursday, April 25, 2002 12:56 PM
> >         To:;
> >         Subject:        Re: GI biopsy blues
> >
> >         Donna,
> >
> >         We process and cut large numbers of GI biopsies daily in three
> > laboratories. Only one lab has a processor dedicated to GI biopsies, the
> > other labs process along with the routine surgicals. All three sites
> > sporadically have some days with microchatter(venetian blinding). All
> > use NBF for fixation, all use the same processing reagents, all cool the
> > blocks on ice trays, no ammonia water.
> >         This cuttting artifact is independent of processing times, it is
> > seen more readily after short(less than 4 hours) fixation times in NBF.
> > After all, the shorter the time in NBF the greater the fixation in
> > processing alcohols!  But the cause is still operator and workload
> > dependant.
> >         The effect is mainly seen on very busy days with technologists
> > are under pressure, either real or imagined, to 'get the work out'. In
> > case, when the block has been re-cut and the same operator instructed to
> > SLOWLY, the microchatters have been absent!!
> >         I would recommend that when any tech in your lab has a
> > episode with a case, carefull, SLOW, re-cuts of the block will solve the
> > problem.
> >
> >         Regards
> >
> >         Bryan
> >
> >         Bryan R. Hewlett
> >         Technical Specialist
> >         Department of Anatomical Pathology
> >         Hamilton Regional Laboratory Medicine Program.
> >         Ontario, Canada
> >
> >                 ----- Original Message -----
> >                 From: 
> >                 To:
> > 
> >                 Sent: Wednesday, April 24, 2002 5:53 PM
> >                 Subject: GI biopsy blues
> >
> >                 Hi Everyone,
> >
> >                 I am faced with some GI microchatter that has occurred
> > recently.  This is a sporadic matter but as of this afternoon, I am
> > currently ensued in a battle with my lab manager over the soaking of
> > in ammonia water. She thinks everything needs to be soaked, I say it is
> > necessary but she is insistent and I want to change her mind. I see no
> > to expose myself to ammonia fumes unecessarily.
> >
> >                 I have one tech that soaks everything in ammonia water
> > there is no difference between her slides and the ones I cut that are
> > and placed onto wet ice. I am literally at wits end regarding this
> > and do not want to submit to "ingesting" ammonia water if at all
> > Are there any articles written on ways to prevent microchatter? One last
> > thing I should mention is that we process our GI biopsies along with our
> > other larger samples (breast, colon, thyroid, etc) and everything else
> > out looking great.  I am not at work at the moment and can't remember
> > processing schedule right of the top of my head but the solutions we are
> > using is as follows: formalin x2, 80% ETOH, 95% ETOH x2, ABS x3, xylene
> > of course infiltrating with paraffin. I will post the exact scheduling
> > temps later as I can't recall those now.
> >
> >                 Any suggestions would be appreciated! Thanks in advance,
> >
> >                 Donna Barlow
> >                 Section Head, Raleigh Community Hospital
> >

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