Salt + Water + Fibers = Synthetic Human Body

Models used for testing medical devices range from the gold standard – a live human – to inadequate models that design engineers assemble themselves. Some even resort to using twisted up pieces of rubber tubing to simulate vessels for design validation testing. Obviously, this approach misguided, not just for medical devices but for any product requiring testing. Engineers relying on data from a poorly conceived test environment may move a design in the wrong direction, leading to increased development costs or a product never reaching its final stage.

Enter Dr. Christopher Sakezles, president and chief technology officer for SynDaver Labs, Tampa, FL, and a life-like synthetic human body that looks, and reacts, like the real thing.

“The basic idea behind the SynDaver Synthetic Human was born in my garage in 2004,” Sakezles states. “The company name has changed a few times since then, but we still make synthetic tissues and body parts for medical device companies, hospitals, medical schools, and the actual end users of medical devices – such as surgeons, nurses, EMTs, etc.”

Ideas, Development
Sakezles’ previous career was as a medical device designer, and in 2004, he left his last industry job to work as a contract engineer offering medical device development services – naming his company PPI (Princeton Product Innovation). One interesting idea he began marketing at that time was a synthetic tissue technology he had been toying with since graduate school.

“I was working alone at PPI and it was very tough going – as it turns out, no one was terribly interested in hiring me. Eventually, I realized that my prospective clients were much more interested in my synthetic tissue technology than they were in my engineering skills,” Sakezles explains. “And at that point I decided to stop selling services and focus on selling models, changing the name to Animal Replacement Technologies, roughly around 2005.”

Moving forward with this plan, Sakezles began a series of elaborate live tissue studies to collect the data on which his organ an tissue models would be based. In the beginning, sales to medical device companies comprised more than 95% of his business. However, around 2009, the name of the company changed again, this time to SynDaver Labs, and the list of clients and types of users of the products expanded as well.

Today, SynDaver Labs not only sells to medical device developers, but to the consumer products and pharmaceutical industries, U.S. and allied militaries, and veterinary students as well.
 

SynDaver Labs offers three distinct product lines: SynTissue Research Products for medical device design verification and validation testing; the SynDaver Synthetic Human product line for surgical simulation and clinical task training; and SynAtomy Anatomical Models and tissue trainers for basic medical skills development.

Tissue and Bones
“We now make a wide range of products – everything from simple veins and arteries – to complete bodies, head to toe,” Sakezles explains. “We have a standard product line but we customize all of it and can build pretty much anything.”

One might wonder about the materials which make up the synthetic body; surprisingly, it is water and fiber. On average the SynDaver body is 85% water, combined with a wide variety of fibers, and the addition of different salts and other compounds to modify optical, thermal, and dielectric properties.

“The secret to creating a high fidelity model is not to squirt silicone into an organ mold. That accomplishes nothing unless you are looking for a paperweight or a pretty display, but a great many companies produce these kinds of models in spite of the fact that they are not very useful.

“We go down to the individual tissue level, putting together organs, muscles, veins, and arteries, all from individual synthetic tissues that mimic the different layers of the organ tissue,” Sakezles states. “In addition, we make these components with materials we have developed specifically for this function, not from another industry and adapted to our needs.”

SynDaver models actually employ more than 100 different tissues and have a complete muscular and skeletal system. The bones – which include cortical, cancellous, and marrow structures as in real bone – have a much lower water content, with the primary component of the bones being composite materials.

These bones offer the same realistic feel to the design engineer, the student, the surgeon, or end users in training.

Sakezles notes that, “In addition to SynDaver bones, we also use plastic bones and real human bones in our models. It really depends on what the client wants. If the model is being used to test a medical device that will be used in soft tissue, then there is no need to employ a model with composite or human bones, as that will just add functionality that our client will not need.”
 

Those that Benefit
Enthusiastically, Sakezles is quick to note that, “The return to the user depends on the industry using the model. We have different SynDaver products for different industries, but they all gain in the same way from the investment. One such customer could be the medical student using a suture pad, sold in campus bookstores for developing the basic motor skills necessary to manipulate tissue. The benefit to this customer is, with the SynDaver product, they are working with something that is more realistic than silicone, but still pretty close to the same price-point as the butcher shop remnants they formerly used to hone their techniques. Students have traditionally used pig’s feet, bologna, oranges – pretty much anything to help develop skills – but with SynDaver they have a venipuncture pad that is almost exactly like live human tissue.”

As you move up the chain of SynDaver users, Sakezles says that EMTs, nurses, and surgeons benefit by utilizing a training platform that is more realistic. Another reason the SynDaver is finding more use in the training environment is that currently, according to Sakezles, the models available to the end users are both not very realistic and too expensive, meaning that training is either inadequate, not performed often enough, or both. SynDaver Labs’ offering are essentially making good models affordable to the end user needs.

“Right now, I think there is a lot of negative training transfer that goes on because of the poor quality of models that are used. Essentially, that just means that people are learning to do things the wrong way because the models are pushing them that way. This is essentially the same effect as what occurs in the medical device development side – where use of a bad model drives design in the wrong direction,” Sakezles states.
 

Drawbacks?
If you compare two things, you can find drawbacks for both.

“For example, if I had to play devil’s advocate, the drawback of simulation is that it is just simulation and it costs money. However, you cannot really make an argument against training, and on the device side development testing is mandated by regulatory bodies – it has to be done,” Sakezles notes. “Our products are designed at the most basic level to perform like live tissue – with all of the frailty that entails. Our product are also 85% water so they will not be as robust as a model made from metal, plastic, and rubber.”

Sakezles explains that their models will essentially last forever, as long as they are cared for. SynDaver Labs’ products cannot be left out on the desk 24/7 – they require storage in the cases that SynDaver provides, but this is minimal effort to have lifelike tissue and components with which to train and develop.
 

Motion and Beyond
The original idea behind the SynDaver body was training, testing, and tissue-based studies. Today, however, Sakezles makes note that research and development has moved into the robotic arena. Although the SynDaver model he refers to is not really a robot in the sense one typically conjures up when hearing that word, it does incorporate technologies beyond water and fibers.

“Today we offer a SynDaver model that incorporates actuators and controls which allow different parts of the body to move. In addition, we are working on the incorporation of additional controls and sensors to facilitate control and feedback from a wide range of body systems. All of these items, such as the sensors, are sourced from various companies, as we only produce the soft tissue in our facility.”

1. SynDaver Labs manufactures the world’s most sophisticated synthetic human tissues and body parts. 2. The focus of SynDaver engineers has been the development of synthetic human tissues for use in medical device verification and validation tests. However, they are now in the process of simultaneously increasing the number of tissues in their library, expanding the body of live tissue data, which is the basis of these materials, and reducing the overall cost of the technology. 3. Comprised of water, fibers, and salts, SynDaver Labs’ synthetic tissues are validated for mechanical, chemical, thermal, and dielectric properties against the relevant living tissue.

The ultimate goal, Sakezles notes, is a SynDaver model that they can manipulate on a finer level – one where they can control respiration, pulse rate, body temperature, and blood pressure in different areas of the body. Sakezles mentions that they have the basic systems in place for this now, but it is not available for sale yet.

“Right now the current product we sell would be comparable to an animated cadaver – a synthetic soft-tissue body with actuators that impart motion,” Sakezles says. “We can hook it up to our heart pump and make blood flow through the arteriovenous system, hook it up to our ventilator and make it breathe.”

From here, Sakezles explains, they are working on additional functionality to control specific parts of the body. For example, they want the cardiovascular system to function automatically, with the ability to control pressure and flow in discrete regions of the body – essentially an untethered version of what they currently have with the external heart and lung drivers attached.

“Our ultimate goal is a SynDaver body governed by an open-sourced, internal autonomic nervous system. This will tell the heart to beat, the blood vessels to constrict or open, control respiration, and enable the body temperature to change. It is just a matter of working on the controls of the system at this time.”

Sakezles could talk for hours about the SynDaver, and notes that what SynDaver Labs offers to the medical device industry is unprecedented, and what is available on the education side is a tremendous leap ahead.

“Pretty much any model that is available in industry today, we will be making an analog of it, one that that has 10 times the fidelity at half the cost. We are working to continually answer demand,” Sakezles concludes.
 
 

SynDaver Labs
Tampa FL
www.syndaver.com