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Plastination

Anatomy Lesson

"Bodies... the exhibition" shows a fascinating and painstaking spectacle of the human anatomy

REPRODUCTION: BODIES... THE EXHIBITIONOrigin of movement: the four layers of muscles that cover bones, blood vessels and nervesREPRODUCTION: BODIES... THE EXHIBITION

What do we have there? The body visible in its complete materiality, layer after layer, and perceptible in its adaptations to movement, in its many functions, one after the other, until its fantastic functionality is understood.  The body insistently reiterated, entire, afterwards dissected in parts, in slices, bones, muscles, nerves, vessels and viscera. In a stunning multiplicity, it offers itself to the eye of the layman in this exhibition that has been thought out in each detail to illuminate a fascinating, startling, perhaps, and painstaking spectacle of the human anatomy.

We are looking at Bodies… the exhibition, in a space of 3- thousand square meters in South Sea Port, in Manhattan, New York. But we could equally be in Miami, Seattle, Las Vegas, London, Berlin, Amsterdam or Tokyo, and the exhibition could be called Body worlds, Body exploration, The Universe within or Bodies revealed and it would make no difference. In all these exhibitions, popularized in recent years to the point of now having attracted tens of millions of visitors since the pioneering one of them – Body worlds, of 1996 -, what makes it possible to put on stage this hyper-real human body is a technique called plastination, or plastinization, created by the German anatomist Gunther von Hagens in 1975, patented in 1977, and refined until being in a condition for being used in 1990.

He himself was the organizer of the first exhibition, which added to plastination a rare virtuosity in dissection, capable of disclosing, without damage to the integrity of what one wants to display, everything that is hidden beneath the skin. Hagens would say that he had recovered dissection techniques from China and from other Asian countries. Right away at in the pioneer display, the potential of these exhibitions for arousing polemics, particularly ethical ones, became patent. There were questionings about the origin of the cadavers and the existence or not of prior authority for their use, although Hagens had always averred that the bodies were given him voluntarily, according to the terms of a strict contract that governs the donations. It was argued that the exhibition offended human dignity and the ethics of doing science. But, anchored on the growing interest of the public, the exhibitions multiplied, little by little constituting an excellent business, with undeniable educational value. Simultaneously, the use of plastination was disseminated amongst anatomy laboratories all over the world, confirming the excellence of the method for training medical and nursing students, amongst others, both in the anatomical details of the human body and in its integrated whole.

The dissemination of plastination in scientific circles began before the exhibitions, and at the beginning of the 1990s reached Latin America in the hands of Professor Aldo Junqueira, from the Faculty of Medicine of the University of São Paulo (USP), who in that year did an internship of four months with Hagens at University of Heidelberg, in Germany. “At a congress in Rio de Janeiro in 1988, I got to know Gunther’s work and I realized the importance that it had for updating anatomy studies”, Junqueira says. Including cross-sectional anatomy, fundamental for the interpretation of the images obtained by tomography, magnetic resonance and other visual techniques that slice the body. “It has to be noted”, he goes on, “that only 5% of human beings have total spatial capacity, the ability to intuit with clarity how the elements are distributed in space and form volumes, from images in two dimensions or of isolated parts”. This percentage is also valid for medical students. “Look, to try to perceive anatomy without spatiality is something sterile, the closer we put medical students to this real spatialized anatomy, the better we train them”, he says.

Brazilian experience
It was with this perception that Junqueira began a transoceanic dialog with Hagens, talking with him “once a week”, until the internship in Heidelberg – before the anatomist was severed from the university, amongst other things, for carrying out the public dissection of a cadaver, and charging entrance fees for the spectacle. As full professor of Surgical Anatomy in Medicine at USP, in 1994 Junqueira presented FAPESP with a first request for financing for experiments with plastination, under the Research Infrastructure Support Program, which at that moment the Foundation was starting. Another financing was to follow, making up a total of R$ 187 thousand. The result is measurable today, not only in plastinated bodies for exhibitions (although a few pieces are at Science Station, in São Paulo), but in some 2 thousand resin boards with extremely thin slices of the human body, useful for anatomy lessons. “The record is one piece only 1 millimeter thick, very difficult to achieve. The bread and butter are pieces of from 2.5 to 3 millimeters thick” Junqueira comments.

With impeccable didactic concision, by the way, he explains the steps for getting these boards and Hagens’ method for plastination. “The method rests on two fundamental questions for the preservation of the body after death: dehydration and the creation of an adequate medium for preventing the proliferation of funguses and bacteria and hence to ensure the maintenance of the tissues and other anatomical structures”, he says. Known since ancient Egypt, dehydration is achieved by immersion in different alcohols, and afterwards in acetone. “In two or three baths of acetone, by steam pressure, you manage to put acetone where there was water before. If this replacement reaches close to 99%, we consider the body to be dehydrated.” Having done this, as the steam pressure of the acetone is low, that is, it evaporates at between 18 and 22 degrees Celsius, the substance tends to leave the “specimen”, to use the language of the anatomists, naturally, and the vacuum remains.

Before proceeding with the plastination, it is worth observing that another enemy of the preservation of the cadaver is fat. That is why in general goes about removing it after dehydration. How? By means of baths in trichloromethane, a substance that has to be manipulated with care, because it can affect the spine marrow and the nerves of those who deal with it.

With the pieces dehydrated and degreased, the touchstone of Hagens’ method is reached: the empty spaces will be filled by silicone or epoxy resins in monomer form, in a more meticulous work than its linear description may make one believe.

With regard to the boards with which he works in the anatomy lessons, and for the preparation of which he has trained technicians and students, Junqueira explains that the thin slices are made with a circular saw on the frozen body. “Without this, syntopy could not be maintained, which is the correct contiguity between one organ and another”, he says. Next, the whole process of dehydration and plastination has to be followed, in this case with the lamina placed between glass boards, where more epoxy resin will be put. And with the additional care of taking out of the piece, with little sticks, any bubbles of air. At the end, the assemblage goes to an oven at 57 or 58 degrees Celsius for 24 to 36 hours, for the epoxy resin monomer to polymerize. What is startling in the technique, whether for scientific or educational purposes or for good business, is how much the human body, alive or dead, can be a total object and fascinatingly objectified.

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