You answered most of your own questions. The bone should be fixed before decalcifying it. After that it could be cut in the cryostat, but why to do that? It will be quite difficult. The best solution is to fix → decalcify → process routine by embedding in paraffin → cut "conventional" sections. The whole idea behind the FS is the speed of the "intraoperative" diagnosis.. Once that is lost (by fixing → decalcifying) I don't think it matter much waiting a little bit more. Hydrochloric acid does not fix (answering to one of your questions). René J.
--- On Sun, 11/29/09, nap...@siscom.net <nap...@siscom.net> wrote: From: nap...@siscom.net <nap...@siscom.net> Subject: [Histonet] bone fixation and decal question To: histonet@lists.utsouthwestern.edu Date: Sunday, November 29, 2009, 1:53 PM Question regarding fresh tissue, in this case bone. Scenario: Mohs surgeon removes layers of skin on a patient's scalp, eventually discovering the basal cell carcinoma extends to the periosteum and so a bit of bone is taken and tested to ensure the margins are free of cancer. The only problem is that since it is bone, in order to cut it is needs to be decalcified. In order to decalcify this tissue in order to cut it either in cryostat or on regular microtome, it of course must be fixed, correct? Reason being is I have heard of Mohs dermatologic surgeons taking bones frags, letting their histotech put the fresh bone in hydrochloric acid solution for decal overnight and then cutting it in the morning on the cryostat. This seems flawed to me as the acid would seem to destroy architecture and critical proteins? Isnt this practice flawed as it doesnt allow fixation? Does the hydrochloric solution have fixative properties? Does decal halt autolysis? Also, is there any real reason why formalin fixed tissues cannot be mounted in OCT and cut frozen? Would it hurt the frozen section for the specimen to be placed into one of the decals i have seen that are both fixative and decal? (Like Surgipath Decal I)It is said to work reasonably quickly and the bone would be thin. Seems like this would be the thourough way of getting quick intraoperative results with a bit of bone on cryo. Any comments? thanks in advance _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet