For about the last 30 years, anytime a patient has colorectal surgery, either for cancer or for inflammatory diseases like ulcerative colitis, they have to worry about certain risks associated with the post-operative healing process due to the use of surgical staples, which can crush and puncture tissue. Leakage, inflammation, infection, and bleeding are the primary concerns with this method of bowel closure.

But a new staple-free closure device recently launched in the U.S. for colorectal surgery could introduce colorectal surgeons to a way of joining two segments of bowel that is very different from what's been done for the last three decades. According to NiTi Surgical Solutions (Netanya, Israel/Chesterfield, Missouri), the ColonRing is designed to help the patient's body heal naturally after this type of surgery.

NiTi says the FDA-cleared, CE-marked ColonRing represents the first major advancement in this area in more than 30 years and could address the major drawbacks of staples.

NiTi CEO Itay Itzhaky told Medical Device Daily that for the past three decades two device companies have controlled the colorectal closure space – US Surgical (now Covidien; Mansfield, Massachusetts) and Ethicon Endo-Surgery (Cincinnati), a business of Johnson & Johnson (New Brunswick, New Jersey). In fact, he said more than 95% of staplers used worldwide have been sold by one of those two companies.

There are two types of staplers, Itzhaky noted, circular staplers which are commonly used for colon and esophageal surgery, and linear staplers which are more commonly used in the small bowel and gastric applications. The major problem with using staples for bowel operations is leakage which Itzhaky said can be quite dangerous – even life threatening – because spillover from the bowel can lead to infection. He said the leakage rate can be up to 25% depending on what part of the bowel has been operated on. Of course there is also the risk of bleeding, he said, which occurs between 4% and 8% of the time, depending on what part of the bowel it is – the bleeding rate is much higher when staples are used in the small bowel, he noted.

"What we are trying to use in our product is actually BioDynamix technology relying on compression," Itzhaky told MDD.

Because NiTi's colon ring is staple-free, there are no bowel wall punctures, no risk of staple line bleeding, and no permanent foreign bodies in the bowel as can happen with surgical staples, Itzhaky said. In the ColonRing, the Nitinol leaf springs stretch to open the ring for placement in the bowel, and then gradually return to their original closed position, adapting to variations in tissue thickness, and accommodating compressed tissue, the company said. The Nitinol leaf springs continuously apply force range of pressure around the full circumference of the anastomosis (the surgical connection of two parts of a hollow organ). As the compression progresses over several days, the tissue trapped within the ring becomes necrotic, while healthy tissue is generated along the ring's outer perimeter, according to NiTi. Itzhaky said the device is expelled out of the body between 7 and 14 days.

NiTi said the ColonRing is designed for anastomoses throughout the alimentary tract for the creation of end-to-end, and end-to-side anastomoses in both open and laparoscopic surgeries. The device is a sterile, single-patient, single-use device, the company noted.

According to the company, more than 500,000 surgeries involving GI tract resection are performed in the U.S. each year.

The ColonRing is comprised of a material called Nitinol, a metal alloy that contains nickel and titanium. Nitinol exhibits "shape memory" the company said. The ColonRing is placed in cold water prior to surgery – and once implanted, the patient's body heat causes the Nitinol to return to its original shape, which is what encourages the natural surgical connection of the two parts of the bowel.

Itzhaky said NiTi is taking advantage of one special quality of Nitinol – its ability to force enhancement on tissue and the ability to be able to control the exact force you need to help the body to heal itself naturally. That makes the healing process safer and reduces the leakage rates and other risks that occur with the stapling method.

Itzhaky told MDD that since the ColonRing has been available in the U.S., the vast majority of doctors who perform colorectal surgeries have been willing to try the device because the concept of compression of anastomosis is something they were already familiar with; they just didn't have the tool to do it until now.

NiTi also has another product in its pipeline, the Hand Compression Anastomosis Clip (CAC) 30 for side-to-side and end-to-side anastomeoses. The Hand CAC 30, a palm-sized applier instrument, is designed for colorectal, gastric and upper GI surgeries, NiTi said. The design and "excellent maneuvering capability" advances open and hand-assisted laparoscopic surgery (HALS) techniques, according to the company. Like the ColonRing, the Hand CAC 30 is also a sterile, single-patient, single-use device, and is also FDA-cleared and CE-marked.