Children’s Hospital in Argentina Finally Gets 3D Printed Presurgical Models

For the first time, a presurgical technique using 3D printing was used on four children suffering from congenital heart disease (CHD), holding promise for future developments. The idea was proposed by Ignacio Berra, a pediatric cardiovascular surgeon at Garrahan Hospital, in Buenos Aires, Argentina, who worked with 3D printed aortic valves of the patients and a 3D printed device of his own creation to carry out tests prior to aortic valve repair surgery. 3D printed medical models are being developed to assist professionals while preparing for complex surgery all over the world. So far they have been quite successful since doctors get to manipulate the model, just like they would do in the actual surgery. Using medical imaging to recreate anatomical models of a patient with any of the different materials available today, leads to accurate and customized models. It’s not the same going into surgery after looking at a 2D formatted image of a child’s heart than actually being able to grasp an exact replica. Berra has been attempting to implement pre-operative planning at the hospital where he works for a few years and just last month he was able to do so, partly thanks to his 3D printing startup, LEW, which developed the four aortic valve reconstructed models for free. In a country where public hospitals have no research institutions associated with them, this is a big step.

Ignacio Berra at Garrahan Hospital

Berra operates on an average of 15 children every week. One-third of complex children heart diseases in the country are resolved at Garrahan Hospital; also children from Bolivia, Chile, Uruguay, Paraguay, and even the southern cities of Brazil travel there just to get surgical procedures. Berra has worked at Garrahan since 2006, except when he won a scholarship to train together with other researchers at Boston Children’s Hospital and Harvard School of Medicine four years ago. When he returned, he was eager to use 3D printing for medical devices and so started working on developing presurgical models of the aortic and pulmonary valves in children with severe aortic insufficiency, as well as applying his 3D printed intraoperative test device for aortic valve repair (which he developed during his time in Boston).

The idea–which could also be performed in adults–would benefit 50 children with aortic valve failure every year. According to the specialist, if the aortic valve does not work properly, it can interfere with blood flow and force the heart to work harder to carry blood to the rest of the body, which causes difficulty breathing, fatigue, chest pain, loss of consciousness, arrhythmia and can lead to sudden death from heart attack. Moreover, in an interview, Berra suggested to 3DPrint.com that performing cardiac surgery in a child is far more complex than adults because the anatomy is not always the same. Actually, he says that the anatomical configuration of the aorta changes a lot. So this is why he insists on preparing prior to the surgery by training on a 3D printed aortic valve model that is completely customized. 

“To get the full picture of what I would encounter during the surgery, I had to first print a replica of each of the four children’s aorta from a CT scan, using Matlab. Once the model was done, I then stitched a pericardium valve (pig pericardium is quite common at this stage because it assimilates the human one) to actually simulate the child’s valve. Finally, using a device I designed in 3D to evaluate the repair of the aortic valve, I pressurized the model with a solution to simulate the diastolic pressure the patient will have, and used an endocamera to evaluate the valve and test whether it closes well and would be able to withstand the blood flow post surgery. After the test in the lab was complete, I moved ahead with the actual surgery,” explained Berra.

The 3D printed aortic valve model without the pericardium (left) and with stitched pericardium (right) for testing prior to surgery (after a while, the pericardium dries up)

The customized models help generate personalized medicine and successful surgeries. That was exactly what happened during Berra’s four surgeries, with children achieving complete recovery and going home quicker than they would have otherwise. During surgery, he uses part of the pericardium (the membrane that covers the heart) of the patient to rebuild the valve that is malfunctioning, so it adapts perfectly to the anatomy. So far, other techniques used to reconstruct children’s valves include the Ross procedure (using a diseased aortic valve) or a mechanical prosthesis.

Software modeling of an aortic valve

Berra is currently in talks with Carin van Doorn, Head of Congenital Cardiac Surgery at Leeds Teaching Hospitals, which is part of the UK’s NHS Trust network (the biggest provider of specialist NHS services in England), in the hopes to work together rebuilding valves for children who suffer from a disease that obstructs the right ventricular outflow tract in England. Berra is hoping to first reconstruct the valve using 3D software, before moving to the operating room (OR) where he hopes a prosthesis made with the patient’s own pericardium will last longer (just like he did in Argentina), this significantly reduces the number of times the patient needs to go back into the OR during his lifetime. 

Berra is the first medical specialist in the country to work with 3D printing and encourages others to follow his lead. But it has not been easy. The country is not part of the technological revolution that has evolved quite rapidly in developed nations. With limited financial resources, low levels of learning, limited opportunities for the poor (36% of the population), and chronic conflicts with teachers’ unions, it might take decades to catch up to the rest of the globe.

“To solve problems, the way North America, Europe and Asia are doing, we need education at each and every level, and not just education, technological know-how from the earliest years. That’s one of the things that’s missing and it’s hurting our chances to be a competing force in the region. Every day I struggle to implement 3D printing technology at public hospitals, to help surgeons during procedures, and patients to recover quicker, but it’s no easy task, people are still afraid of change and bureocratic procedures are timely and costly,” he revealed.

The aortic valve model after being printed on Stratasys

Berra’s company LEW produces presurgical models, both for his personal use at Garrahan Hospital and for fellow doctors that are curious about implementing 3D printing technology to their work. Each model made on the company’s Stratasys Objet30 Prime with Stratasys‘ own resins costs around $200, and they are not yet charging fellow doctors and hospitals for them.

At LEW, Berra is currently developing a perfusion system that allows preserving an organ for transplantation in conditions similar to those of the human body and is expected to double the number of interventions in the country, and along with his team, they are developing an artificial heart, also using 3D printing.

The specialist claims his work to help young patients will not stop, no matter how many hurdles he has to tackle in the way. With aspirations to work mainly in Argentina, Berra does not discard moving to the UK or Boston, where his ties with other specialists in the field could help him achieve his goals. Like many in the field, he believes training pediatric surgeons for the future should involve acquiring knowledge on 3D printing technology to aid the work, and with a limited amount of cardiovascular surgeons specializing in children, they can use all the help they can get.

[Images: Ignacio Berra and 3DPrint.com]

The post Children’s Hospital in Argentina Finally Gets 3D Printed Presurgical Models appeared first on 3DPrint.com | The Voice of 3D Printing / Additive Manufacturing.

Pediatric Surgeon 3D Prints a Aortic Valve Repair Testing Device

Nations around the world are taking steps to prevent heart disease, with both advice and legislation to promote healthy eating habits, annual check-ups, and even antismoking laws and regulations. But for some patients, it is not about a change in lifestyle, since heart ailments are part of their daily life. For children born with congenital heart disease (CHD), a birth defect in the heart that can be the cause of serious health complications later on in life, pediatric surgeons around the globe are trying to raise awareness about this most common birth defect. According to estimates, one in 1,000 babies is born with the condition every year. This means an annual 1.3 million CHD births. It usually entails an anomaly in the heart walls, valves or blood vessels, ranging in effect from simple defects to life-threatening conditions. In Argentina, pediatric cardiovascular surgeon Ignacio Berra has been searching for solutions to CHD his entire adult life and last year he designed and perfected an intraoperative test device for aortic valve repair using 3D printing.

How the device works

Since 2006, Berra has worked at Garrahan Hospital, in Buenos Aires, but in 2015, he won a scholarship to train together with other researchers at Boston Children’s Hospital and Harvard’s School of Medicine, where he began working on the device. The technique was presented at the Aortic Symposium held by the Association for Thoracic Surgery (AATS), and detailed how pediatric surgeons are trying to intraoperatively test and visualize the valve in its diastolic state (part of the cardiac cycle during which the heart refills with blood). The aortic valve pressurization device enables a regurgitant aortic valve to be inspected under typical diastolic conditions at the start of the repair to better understand mechanisms of aortic regurgitation (AR) as well as allowing surgeons to do a postoperatively test the efficacy of repair and the robustness of valve closure.The gadget was printed on a Stratasys Objet30 Prime 3D printer with a super clear biocompatible resin to allow for visual inspection and is described by Berra and fellow researchers as a two-piece cylindrical tube with a length of 26 cm and a working channel with inlet and outlet valves, as well as a pressurization chamber, which has two side ports. On one side they use it to test the pressure, thanks to a sensor, while the other side port can be used to introduce measurement tools, for example, an endoscope to allow visualization of the valve and aortic root.

“One of the key factors when developing this type of innovation is reproducibility. Especially in developing countries, such as Argentina, where we would benefit from generating this type of device, cheaply, for daily use in operations. Our hospitals are solely about care, so they are missing the in-house research facilities that others have in Europe and North America. This means that in order to keep working and improving the device (as well as generating other projects), I had to create my own 3D printing company, called LEW, with a fully equipped operating room for pre-clinical trials, a Stratasys Objet30 Prime, Stratasys own resins, software and industrial engineers and designers who help us develop the ideas,” explained Berra to 3DPrint.com

The aortic valve pressurization device

According to the specialist, in children, surgical repair of the valve is usually preferred over valve replacement. However, aortic valve repair is technically challenging and is currently in transition from surgical improvisation to a reproducible operation and an option for many patients with aortic valve disease. A major challenge for surgeons during aortic valve repair is to intraoperatively assess valve dysfunction before repair and to predict valve competence after repair. Up until now, there has been no similar test in use for the aortic valve, although the concept has been proposed. So the device is ideal for with children with CHD.

“The model was originally designed in the computer and then 3D printed in three parts and used at Boston Children’s Hospital to test the pressure valve. This means that, by pressurizing and using an endoscope, surgeons can see the closed aortic valve during the intraoperative period while the aorta is transacted, and it only takes one minute. To perform the preclinical trials I used pig hearts, but the method has advanced more in the US, since they are soon going to start a clinical study to formally test its validity with the FDA. In Argentina, we are only using it to test a model of the aorta prior to surgery, but we expect to begin using it in children soon,” Berra went on. 

Trying out the technique at the lab

The technique validates, during the surgery, that the operation was successful and ensures that the child will be fit to continue living a normal life. Berra suggested that “without the aortic valve pressurization device it is difficult for a surgeon to intraoperatively predict valve competence after repair solely on the basis of what they see, that is, to know for sure that the valve will not yield, because if it breaks after the surgery, the turbulent blood flow can lead to endocarditis, a serious infection of the valves.”  According to Berra and the researchers behind the device, this new capability could increase the success rate of aortic valve repair, leading to higher repair rates and encouraging less experienced surgeons to attempt it. 

“Although surgeons are heavily trained, surgeries are not all that simple, each case is different, especially in children with CHD. When we have to work with patients that have such complicated pathologies, there is a need to generate new solutions with what we have on hand, and unfortunately in Argentina, availability is not in our dictionary. Doctors fight against an ancient bureaucratic system to translate an idea into a reality with the potential to save lives,” he revealed. 

Berra’s ambition for research and innovation is a family trait. His father is a veterinary and researcher who instilled a desire for knowledge. Both him and his dad are part of LEW, as well as his sister, an immunologist, and brother, an engineer in charge of designing all the devices before they go through the printer. They are also working on perfecting a 3D printed artificial heart which they plan to make commercially available in the country, and which will cost much less than what an imported version costs, usually around $70,000. With this and many more projects in the works, the company could soon become one of the few generating novel ideas in the region.

[Images: Ignacio Berra and 3DPrint.com]

The post Pediatric Surgeon 3D Prints a Aortic Valve Repair Testing Device appeared first on 3DPrint.com | The Voice of 3D Printing / Additive Manufacturing.