Yes that's a common problem for cryostat sections.
Different people in my lab has quite diverse response to this.
Some suggested that you can leave the brain in O.C.T before put them in to freezer for 3-6 hours, and the O.C.T will "enter" the brain tissue. Then no "cheese".
Some other people tried the other half of the brain on microtome, to see if this helps. To our surprise, these are no such hollow cavities in microtome-made sections. Thus possibly it's related to O.C.T embedding rather bad dehydration/fixation/post-fixation.
Department of ANATOMY
The UNIVERSITY OF HONG KONG
LI KAI SHING FACULTY OF MEDICINE
21 Sassoon Road, Pok Fu Lam
发件人： Aine Behan
发送时间： 2008-07-14 21:58:34
主题： [Histonet] RE: freezing artefact holes on edge of cortex in mousebrain sections
I was looking for info on troubleshooting what I think is freezing artefact
holes (FA) in our tissue sections. It is quite specific to the edge of the
brain sections predominantly around the most superficial layers of the
cortex and most obvious in the most lateral aspects of the cortex in coronal
Brains were fixed in 4% PFA following cervical dislocation and dissection.
They were fixed in graded sucrose concentrations of 10%, 20% and then 30%
over 3 days followed by rapid freezing in isopentane and dry ice. These
brains are stored at -80 until cryostating coronal sections (10 microns
thick). The deeper brain structures are perfectly intact and free from FA
Has anyone observed this before and do you think this is FA or something
else? I can send on a H&E pic if it proves helpful. It might be a bizarre
question but could there be anything to do with the cryostat that could be
羒ne Behan, PhD
Department of Psychiatry,
Royal College of Surgeons In Ireland,
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