Hello Histonetters,

I am having some problems processing en block intervertebral disk specimens 
(flanked by portions of vertebrae).  I am especially interested in 
examining the nucleus pulposus.  The samples are about 1 cm thick, fixed 
for about 10 days in 10% formalin and then decalcified in 5% formic acid, 
anywhere from 1 to 1.5 weeks.  The processing schedule I am using is 1.5 
hours in each of the dehydrating, clearing, and paraffin stations.  After 
coarse trimming to the area of the nucleus pulposus, I am finding that this 
portion of the paraffin block is soft like is was improperly infiltrated 
and/or processed.  For the most part, the anulus fibrosus is intact except 
at the nucleus pulposus interface.

Is this simply a matter of increasing the processing times or is there 
something else I am neglecting to do?  Any help would be greatly appreciated!

Gratefully yours,
Tracey

Tracey Couse
Laboratory Coordinator/Histologist
Georgia Tech/Emory Center for the
    Engineering of Living Tissues
Georgia Institute of Technology