Date:          Thu, 25 Feb 1999 14:05:01 -0600
From:          Robert.Lott@bhsala.com
Subject:       Retic stain(s)
To:            histonet@pathology.swmed.edu


Dear M.
Retic.stains are not difficult and the Gomori method is a great technique...
but you "MUST" remember one important factor.  Inconsistent results are
caused by the way the "ammoniacal silver solution" is made.  The sensitivity
of staining is controlled by the balance between ammonia and silver nitrate in
this solution and you "MUST" be careful not to add too much ammonia when
clearing the solution. Stop short of a clear solution and err on the side of
"dirty" if you know what I mean.  This is the biggest mistake histotechs make
when making ammoniacal silver.  Filter the "dirty" solution and proceed.
Livermakes the best control for retic stains.

I have assumed that your oxidizer, sensitizer and reducing solution are all
fresh!

Robert Lott, HTL(ASCP)
Baptist Health System
Birmingham, AL

Dear all,
I agree whole heartedly with Robert that Gomori Reticulin technique
is great, but the ammonia:silver ratio is critical and the staining
results previously described are definitely due to the "quality" of
the ammoniacal silver solution.  If you have someone in your lab who
consistently makes it correctly NEVER let them go.  My mentor a PhD
in histochemistry always said the time to stop dissolving the
precipitate was when there were approx. 20 grains left in the bottom.
Then invert the stoppered measuring cylinder 20 times before adding
any more ammonia (if required).  There is always a little excess
ammonia on the sides of the container and this most often completes
the process.
Too much ammonia can also be the cause of sections floating away
during the final steps in the Gomori procedure.

Good luck
All the best in Histotechnology
Bill Sinai
Department Manager
Tissue Pathology
ICPMR Westmead Hospital
WESTMEAD NSW AUSTRALIA
Phone 61+2+9845 7774  Fax 61+2+9687 2330