St. Louis Researchers Ask for Stratasys Direct Manufacturing’s Help in Creating Accurate 3D Printed Models for Surgicial Training

Dr. Saleem Abdulrauf

We’ve come a long way from bloodletting and snake oil treatments, but when it comes to the medical profession, the challenges in training medical students as well as experienced surgeons for new procedures have persisted. There’s simply nothing as good as training with the real thing—and humans generally are not down for being operated on unless it’s a necessity. So, throughout the ages, medical professionals striving for excellence—and most importantly, good patient outcomes—have often gotten very creative with their training materials. Today, however, with the advent of 3D printing, we’re seeing a host of improvements in simulation for students and surgeons.

Considered the premier forum for education and training for neurosurgeons, Walter E. Dandy Neurosurgical Society offers the newest practices in training for providing better patient outcomes. There, Dr. Saleem Abdulrauf acts as the president of the society and also works with 100 universities worldwide, along with serving as the professor and chairman of the St. Louis University Department of Neurological Surgery and as Neurosurgeon-in-Chief at St. Louis University Hospital. As the efforts of many have come together, now the Department of Neurological Surgery and the St. Louis School of Engineering are working together to use 3D printing for training in neurosurgery.

The research teams working together are focused on a study that would allow for a surgical procedure on patients suffering from brain aneurysms. Many of us may have family members who have been affected by such a condition, which is extremely alarming, and the risks of surgery must be carefully considered. With this study, the teams are able to consider 3D training in comparison to that of students and surgeons simulating surgeries on human and animal cadavers, foam models, and other artificial items.

“I personally perform a lot of brain aneurysm surgeries,” said Dr. Abdulrauf. “It is a complex operation given the number of anatomical issues that we’re dealing with under the microscope. I knew if there was a way of simulating those complications before the operation using the same tools and under the same microscope we’d have a higher positive impact on the procedure outcome for the patient.”

Because the aneurysm can be unpredictable and varies in individuals, surgeons are left with a delicate task in reaching them without harming existing tissue in the surrounding area.

“Every aneurysm is different in size, contour, and location. We have hundreds of clips sizes and types we can use and we’re typically making the decision on clip size during surgery. If I can make that decision beforehand by practicing on a model using the same tools and clips I plan to use in the final operation it really makes a difference during surgery,” explained Dr. Abdulrauf.

The idea is to have the simulation be as close to the human brain as possible, so obviously the 3D printed models needed to be at 1:1 scale, and with a texture as similar as possible. The patients’ brain scans were converted to 3D CAD models, with each one then made into a 3D print that was completely unique to the patient. The files were sent for printing to Stratasys Direct Manufacturing, and the teams worked together to make sure the critical areas of the aneurysm were produced with precise accuracy and detail.

Headquartered in Valencia, California, Stratasys Direct Manufacturing is known as one of the undeniable leaders in making 3D printed models for training in medicine. They have created simulators for training in everything from obstetrics to dental, heart, bone and organ models. Because of this, Dr. Abdulrauf and his team chose to use their services rather than their own onsite PolyJet 3D printer. At Stratasys Direct Manufacturing, as the teams worked with the St. Louis University Department of Neurological Surgery to create 3D models of the greatest accuracy, they used both PolyJet and urethane casting, resulting in PolyJet Rigid VeroYellow for the skull and an overmolded TangoPlus material with a durometer of Shore 27A for the brain—a multi-functional piece.

“Within the CAD design, the aneurysm was 3D printed according to the aneurysm pattern experienced by the actual patient,” stated Stratasys Direct Manufacturing in their case study results. “Finally, the skull was built with the inner support material that hugged the grooves and depressions of the sulci and gyri likeness of the patient’s brain. This support material served as the pattern for creating the inner brain matter.”

3D printed model from Stratasys Direct Manufacturing

To mimic the texture of the human brain, the inside of the 3D printed model was filled with a gelatinous colloid material meant to feel like spongey sulci and gyri. So far, the results have been extremely positive:

“I’ve done a lot of aneurysm operations in my career and I can confidently say that having the 3D printed model here has a very positive impact on the procedure results,” says Dr. Abdulrauf. “The model has helped to identify and overcome surgical challenges, like optimum access to the aneurysm or the depth and angle of the approach, before surgery begins.”

As they continue their research with blind studies, Abdulrauf hopes to see a ‘two-arm study’ with half of the residents receiving a 3D printed model of a cadaver’s brain before surgery—and the other half preparing without a model.

“From this study, Dr. Abdulrauf hopes to quantify the use of 3D printed models in pre-surgical planning,” stated Stratasys Direct Manufacturing.

Another study will compare patients who received the traditional gold standard of care during surgery with those who also were operated on by surgeons who used 3D printed models to train with before their procedures. Post-recovery comfort and overall outcomes will be studied as Dr. Abdulrauf continues to measure the success of using the 3D printed models for training.

“The future of medicine is all based on measuring outcomes. The most important thing is quantifying what’s better for patients, and improving the lives of patients. To do that, we must know the absolute best measures we can take using the tools we have to improve their lives,” said Dr. Abdulrauf. “We cannot thank Stratasys Direct Manufacturing enough for the work you’ve done. Having a heart in this kind of work always produces better results.”

Obviously, this is a great beginning in seeing 3D printing being used further in medical training, with so many of the benefits in use from customization offering patient-specific care to speed and versatility in production and more. However, one benefit that Stratasys Direct Manufacturing indicates is not currently being seen in this project is the affordability factor due to the specialization involved in each patient-specific model. Production is and most likely would remain cost-prohibitive for use in many institutions due to the low, highly customized volume involved. Discuss in the Stratasys Direct Manufacturing Surgical Models forum at 3DPB.com.