Crystal Shin is an assistant professor of surgery at Baylor College of Medicine, and the lead author of a study that examines a non-pharmacological solution that provides mechanical support to the site of an hernia, while also keeping inflammation in check—without causing damage to other organs. 

That novel solution, Shin suggested, may come courtesy of 3-D printing. 

Shin told Baylor College of Medicine that although hernia mesh implants are mechanically strong and support abdominal tissue, it’s very common that after a few days after the surgery, the implant can cause inflammation. And this inflammation, she says, can affect nearby organs in as little as two to three weeks. 

Dr. Ghanashyam Acharya, an associate professor of surgery at Baylor, explained, “Mesh implants mostly fail because they promote the adhesion of the intestine, liver or other visceral organs to the mesh. As the adhesions grow, the mesh shrinks and hardens, potentially leading to chronic pain, bowel obstruction, bleeding and poor quality of life.”

As a result of the mesh failure, a patient may require additional corrective surgery. 

Dr. Acharya sayid that the problem with anti-inflammatory drugs that are prescribed to control the post-hernia-mesh-surgical-procedure is that these drugs disturb the healing process because they block the migration of immune cells to the injury site.

In addressing these complications, Drs. Shin and Acharya and other researchers designed a novel, 3-D printed mesh that, in addition to providing mechanical support to the injury site, also acts as an inflammation modulating system,” Shin said.

Here’s how the 3-D printed mesh works: At the site of the hernia repair, certain immunity proteins involved in the inflammatory process called cytokines appear. (Cytokines have received attention because of severe COVID-19 reactions, in which cytokine activity is left unchecked, resulting in the body attacking itself.)

The main cytokines that appear at the surgical site have a positive surface charge. Baylor College of Medicine researchers designed the novel mesh to trap the cytokines and thus reduce their inflammatory effect, by implementing a negative surface charge. 

A 3-D-bioprinter was used to fabricate Biomesh. The mesh was composed of a polymer called phosphate crosslinked poly (vinyl alcohol) polymer (X-PVA). 

According to the researchers, the mesh was designed to withstand maximal abdominal pressure repeatedly without any deterioration of its mechanical strength for several months. 

Moreover, the 3-D biomesh did not degrade nor did the elastic properties degrade over time, nor was it deemed toxic to human cells.

The biomesh was tested on rats, and was compared against another type of mesh used extensively for hernia repair. The rats were monitored for four weeks after they were implanted. According to the study results, the 3-D biomesh was able to capture three times as many pro-inflammatory cytokines as other meshes commonly used for hernia surgery. 

And most importantly, says Baylor College of Medicine, the novel mesh caused no damage to visceral tissues. Furthermore, unlike common hernia mesh devices, the newly-designed mesh did not adhere nearly as much to tissues.  

“These results confirmed that the new Biomesh is effective at reducing the effects of the inflammatory response and in preventing visceral adhesions. In addition, the new mesh did not hinder abdominal wall healing after surgical hernia repair in animal models,” the study concluded. 

Over 400,000 hernia repair surgeries are conducted every year in the U.S. As of late last year, there were approximately 15,000 hernia mesh lawsuits. Dr. Shin told Baylor College of Medicine that this new Biomesh can fulfill a major unmet need to develier a multifunctional composite surgical mesh. 

Further preclinical studies are in the process of being conducted. Then, hopefully, these results will be carried over in clinical trials. 

In addition to creating a potentially less problematic hernia mesh, the researchers say that producing the novel biomesh is highly reproducible, scalable and modifiable.

It’s fitting that Baylor College is the scene of this research. In the 1950s, a researcher at the school’s Department of Surgery, Dr. Francis C. Usher,  developed the first polypropylene mesh for hernia repair.