Medical anatomical illustration - the history of the study of the human body in the atlases of 5 centuries. Final part

In the previous three posts ( 1 , 2 , 3 ) we talked about how the art of anatomical illustration followed the development of medicine and publishing technologies. Over the course of five centuries, the engraving was supplanted by lithography, and offset printing came to replace it - these, of course, are significant changes, but such progress may seem ridiculous against the background of a real revolution that occurred before our eyes. It became possible to three-dimensional modeling and creation of benefits with any level of detail in which the image can be approximated, rotated in all planes, look into any corner and disassemble into layers. However, so far this can be seen mainly in science fiction films, and specialists are content with low-quality models and old anatomy books. Why - let's try to explain.

Decline in quality against the advent of new technologies

Anatomical illustration played a major role in the development of science, because it made it possible to accumulate and transfer knowledge about the structure of the human body. Now anatomy has already taken place as a science, although the structure of individual parts of the body is still being clarified - for example, there are new ligaments in the knee . Research methods are being improved, from tomography to microscopy. Anatomy supplemented physiology, histology, new surgical and diagnostic manipulations, the study of pathological processes and conditions, so that the need for competent visualization has not disappeared anywhere. On the other hand, it became possible to create three-dimensional models and interactive illustrations. However, as many illustrators point out, truly literate and neat works are very rare. In comparison with vivid examples from the past, modern anatomical illustration often looks less detailed and elaborate.
')




Above: drawings from the atlas of Jean-Baptiste Sarlandera edition of 1837 ( source ). Below: illustrations from the modern atlas of Todd Olson , released in 2008.

We asked two well-known scientific illustrators Chris Rockley and Karl Wesker to talk a little about what the quality of the work of an illustrator depends on and why it is now often inferior to what was created in past centuries.
Chris writes that this field of activity requires serious knowledge directly in the field of science:

“One of the possible reasons for the fact that modern scientific illustration often looks rustic, in the absence of special training and understanding of the scientific specifics of the object of the sketch. I know many scientists who prefer to make images themselves for this reason. I have been teaching science and field design at Newcastle University in Australia and in selected groups since 2008. One of the things that I note in artists is the lack of basic anatomy of knowledge and observation skills. As soon as you inform them that you need to draw what you see, and not what you anticipate, everything becomes clearer, and students begin to see details and tiny things that have eluded before. The same applies to medical illustration. We were very lucky at the university, because we had an anatomical laboratory, which made it possible to use real and plasticized corpses for work. Almost like Leonardo da Vinci. ”

Karl Wesker worked on the illustrations for the Atlas of Prometheus , published by Thieme, and the Winking Skull online tutorial. It indicates, among other things, the desire of publishers to get illustrations as quickly as possible:

“The main source for the anatomical illustrations of Prometheus was the study of sections and dissections of the human body. Plus, I have a good library of old and new anatomical books. Here it is necessary to mention the works of Jean-Marc Bourgeri ( Atlas of Human Anatomy and Surgery, XIX century ), Gustav Brezique , Karl Toldt and Werner Schaltholz .
With the advent of computer illustrations, the quality has fallen. Publishers are interested in simple and cheap vector graphics. We have been working on Prometheus for 14 years. Now, no publishing house wants to invest so much time and money. ”

In previous posts, we have given many examples of how the work on one atlas became the work of the artist’s entire life or anatomist. This applies primarily to the early stages of the development of anatomy, the time of Eustache, Fabricius or Kasseri, when scientists and illustrators worked, focusing on the results of the autopsies, which they themselves carried out. Now it’s not so easy to imagine an artist or a 3D modeler who will cut corpses and create an illustration or model based on his own anatomical preparations. Meanwhile, this approach allowed us to create illustrations of a fundamentally different level.

However, Karl Wesker does not lose optimism and sees a huge potential for anatomical illustration in new computer graphics technologies:

“I think that the quality of illustrations has been falling for a long time, since not all artists could fully master the techniques of drawing on a computer, which was required by publishers.
In principle, now a scientific or medical illustration implies the possession of three things: knowledge of the anatomy or structure of the depicted object, the ability to draw and skills in specialized computer programs.
I am sure that something will happen and change the current state of affairs in our sphere. Anyway, I think that the next technical revolution has already begun with the development of three-dimensional graphics, despite the fact that now we are seeing only rather primitive works. ”

Illustrations from satin Prometheus. ( Source )

The technical side of the issue

Increasingly, printed textbooks are giving way to interactive tutorials, both for working in the browser and in the form of mobile applications. The number of authors and companies developing interactive anatomical aids is growing, both for working in the browser, and in the format of applications for a tablet or phone. It is obvious that in such work fundamentally new possibilities are opened by the use of three-dimensional graphics and visualization. After all, the model can be rotated, scaled and studied, removing or adding individual layers or elements, not to mention the possibility of showing the work of certain organs or systems in motion. However, while the potential of modeling is revealed only a small part.

If we talk about mobile educational applications, then among them noteworthy are: Visible Body , Muscle System Pro , Pocket Anatomy , Essential Anatomy , 3D Brain . In addition to these, there are a great many others, the comparison and comparison of which requires a separate post. For acquaintance it is possible to pass on this and this survey links. However, the quality of graphics and detailed models and structures in modern applications leaves a lot of room for improvement.



Screenshots from Essential Anatomy , Pocket Anatomy and Visible Body applications.

The problem of three-dimensional graphics is that you cannot use very detailed anatomical 3D-models, because working with them requires significant computational resources, not only when you create, but, more importantly, when viewed. In this regard, application developers and widgets have to make compromises. If you make a scalable rotating model, you have to significantly sacrifice quality, as can be seen from the example of the Zygote Body project: despite the fact that Zygote is the author and developer of one of the most high-quality and accurate 3D human body models available on the market, the result presented in the widget, it looks pretty rough:



In addition, the technology of the presentation of the model involves uploading 3D data to the user's computer, which carries with it certain risks of further retrieval and unauthorized use of the author's model.

All these circumstances lead to the fact that so far there has not been a breakthrough in detail and quality, which, it would seem, promise modern technology.



At the left: an illustration from the atlas of K.-L. Bonami, P. Broca, and E. Bo (1844). On the right is a screenshot of graphics from the “ Human Bones of a 3D ” mobile application. We suggest that the reader himself go, for example, to Google play and look through the illustrations from the applications on request “ anatomy textbook for medical institutes ”, comparing them with examples from our previous posts.

We are faced with similar problems in the development of anatomical widgets, so we will tell you more about the difficulties encountered and possible ways to resolve them using our own example.
In the discussion of one of our previous posts about virus modeling, we already said that visualization of one frame at the quality level adopted by us, such as the human brain model, on a modern graphics station (dual Intel xeon 2687w) takes a few minutes, while for smooth Rotation of the model by the user must produce at least 15 frames per second.



Slightly better things with the expectation on professional graphics cards, and not on the CPU. But all these solutions are worth thousands of dollars, which are not on the user's side. Moreover, even they will not cope with the task in full. A number of models of maximum complexity, such as, for example, models of HIV or the Ebola virus, in principle, cannot be visualized on the user's side due to the large number of high poly objects in their composition. There are also solutions in the form of specialized environments like Unity, which allow you to create interactive content for online presentation, but they require the user to install the plugin, and as a result are less universal. Although, in fairness they can be eliminated by the criterion of quality.

For these reasons, we chose the option of pre-calculating and sending the finished graphics to the user without delay. There are, of course, disadvantages - the restriction of the freedom of rotation of models, a large amount of traffic to transfer images at high resolutions. But if the interaction logic and user scenario are well thought out, then the first “minus” can be almost leveled by adding, say, changes in transparency, appearances of necessary signatures, slices into the visualization itself, which is great to saturate the final product with information and will solve the problem optimally.

Anyway, the creation of anatomical three-dimensional models is not only extremely interesting, but also very laborious, since it involves many stages from finding the correct references to developing widgets and plug-ins that organize work with the model for the end user. Recently, we have completed work on a new system for creating educational web applications. One of our widgets allows you to view a model of a human skull from different sides, find individual bones in a model, click on their name or find out the name of a bone in one of five languages, click on a model, and also contain a description of all the elements.



Screenshot widget.

In this case, our initiative in this area, like our colleagues, is to create free high-quality educational interactive tools for the new generation, in which the possibilities of modern technologies would be used and the drawbacks mentioned by Karl Wesker and Chris Rokley would not exist. We will definitely tell about this in more detail in one of the following posts.

Three-dimensional modeling in anatomy and medicine: where to go next?

Three-dimensional modeling can help non-invasive methods of studying the structure of the body and individual organs, such as tomography or 3D-X-ray .
In still not so old times it was not possible to find out how this or that internal organ looks like by cutting the body. Modern technologies allow you to do this, and then use the result to create models, including those printed on a 3D printer. Such commercially available models makes the company Zygote, which has already been mentioned. One of these projects is called Solid 3D Male Body . The authors write that when creating models they used computed tomography data and tried to observe the parameters as close as possible to the parameters of the human body. Such models can be not only useful for educational purposes, but also useful, for example, to designers who design shoes, clothes, and orthopedic devices or interfaces that directly interact with parts of the human body. We use tomograms data when solving local problems, as references of native relative position, sizes and shapes with high-quality highly-detailed modeling.

However, while the technologies of reconstruction and visualization of the results of tomography are far from ideal and do not immediately provide a clear and understandable picture for a non-specialist. There is no doubt that the need for professional 3D-modelers to create educational three-dimensional anatomical graphics will always be.



Image with three-dimensional reconstruction of the CT of the skull with a fracture along Le Fora. ( Wikipedia ) You can compare the details and accessibility for understanding with this video .

On the other hand, three-dimensional modeling based on medical studies of specific patients can directly be useful in the treatment of certain diseases. The models of vertebrae and even fragments of the skull printed on 3D printers are already used in transplantology. This is very convenient because it allows you to easily make an implant of the most suitable shape. Most likely, these technologies will actively develop, and, apparently, in the direction of truly amazing stories like printing scaffolds , on which whole cloned organs like the liver, kidneys or the heart can grow.
Another possible application is the creation and printing of models of human embryos in the early stages of development. It sounds ambiguous, but such a procedure, for example, can help blind parents get an idea of ​​what their baby looks like in the womb .

Another advantage of modeling compared to a static image is that it makes it easier to create animated snippets and videos. From an educational point of view, this is another level up, since animated images describe the physiological processes, medical manipulations or injuries and fractures much better. Even using a static model of camera movement, audio and signatures can give a lot of information and correctly place accents. However, the conversation about anatomical animation also clearly deserves a separate post.