X-Message-Number: 18621 Date: Fri, 22 Feb 2002 05:27:19 -0500 From: Thomas Donaldson <> Subject: CryoNet #18608 - #18620 About freezing or vitrifying brains without skulls: I am not an expert in the details of suspension, but one anatomical fact makes it far harder to freeze a brain alone than to do it inside the skull: the blood supply for our brain comes from outside, it does not come up with arteries inside the brain. This means that the surgery separating a brain from the skull WITHOUT DAMAGE TO ITS BLOOD SUPPLY becomes quite difficult. Since by hypothesis we are doing this BEFORE we put in any protective solution, it becomes even harder ... if we want to lower someone's temperature, we should start doing so as soon as possible, and the best way to do so involves accessing their vascular system. It may someday become possible to do this, but its difficulties have prevented the cryonics societies from any serious attempt that I know of. It's easier to leave the brain in the skull. In terms of the volume of what is frozen, a frozen head takes up far less space than a whole body. Removing the brain from the skull would at best give a small added percentage. Just some thoughts on this issue. Best wishes and long long life, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=18621