Making Minimally Invasive Surgery Even Less Invasive

Some people in the medical-device field believe that surgical science is now on the cusp of a new wave of advancement.

The past 20 years have been a revolutionary period for surgical technology and, hence, for surgical methods. The liberal use of the scalpel has given way to endoscopy, ushering in the current age of minimally invasive surgery.

To enable endoscopic surgery, visionary entrepreneurs have developed a new generation of surgical tools in response to technological advancement. Some people in the medical-device field believe that surgical science is now on the cusp of a new wave of advancement — a wave that centers on the same goals as minimally invasive surgery as we know it today: shorter patient stays and reduced complications and morbidity, but with the added goal of eliminating scars.

This new frontier is known by the acronym NOTES: Natural Orifice Transluminal Endoscopic Surgery. As the acronym indicates, the method uses natural body orifices to gain endoscopic access to organs, thus reducing the use of the scalpel even further. Routes for surgical access being considered are per-oral transgastric, transvaginal, transrectal, transcystic (urinary bladder), and transesophageal.

As pioneering surgeons have recently achieved some operating-room firsts, some medical-device developers are working on new equipment designed to make NOTES possible, easier or less prone to complications.

Among those whose attention has been drawn to this embryonic field is Stephen Van Lue, DVM, a board-surgeon and medical-device inventor with extensive clinical and industry experience. Van Lue is the General Manager, CA and Senior Director of Surgical Research and Innovation with LyChron, LLC, a preclinical research organization in Mountain View, CA. Before joining Lychron, in July 2007, Van Lue was associate professor of surgery at the University of Copenhagen, and prior to that, worked in R&D for leading surgical device companies.

Freelance writer Richard Bierck recently interviewed Van Lue for MDNG New Media, exploring his informed view of the nascent present and promising future of NOTES, and its implications for the development of a new breed of surgical technology.

What’s a good example of a successful surgery employing NOTES methodologies?

In April of 2007 at the University Hospital of Strasbourg, professor Jacques Marescaux, along with Dr. Arnaud Wattiez and additional surgical team members successfully removed a woman’s gall bladder through her vagina using a flexible endoscope… This was a human first — and testimony to the extensive research that has been performed since the NOTES approach was first described by Dr. A. Kalloo in an animal model in 2004.. Additional procedures that are thought to be plausible are appendectomy and tubal ligation – some of which are known to have been performed in humans but are not yet reported in the peer reviewed literature as of this date.

This demonstrates the feasibility of NOTES, for suitable surgical situations and appropriate candidates, using even existing surgical technology.

With some clinical cases now on the books, are NOTES methodologies under review and programmatic development at universities or other medical research institutions?

Yes, most definitely. There’s a newly formed group at the University Hospital of Strasbourg — the European Institute for Transluminal Surgery (EITS) – and they have surgeons engaged in intellectual commerce on the subject with the surgical community. Because NOTES procedures cross the typical disciplinary boundaries of surgical practice, there is a great deal of discussion and early research regarding training, as well as just who should perform such procedures, and, where should they be performed.

The Natural Orifice Surgery Consortium for Assessment and Research (NOSCAR) is a joint effort of the American Society for Gastrointestinal Endoscopy (ASGE) and the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES). NOSCAR’s panel of cross- disciplinary expertise is charged with addressing the introduction of this new technology. And more alliances will be seen, in my opinion, as advanced NOTES procedures are currently being performed using swine models for kidney removal, major intestinal surgery, and gynecologic procedures.

And how is this upwelling interest in NOTES spurring technological development? What’s going on there?

Well, there is emerging industry buy-in in this area. For one thing, Ethicon EndoSurgery [a subsidiary of Johnson & Johnson] is investing substantially, already pledging $1,000,000. in research funds along these lines… On the imaging side, there’s been the development of some robotic flexible endoscopes. A company out of San Jose, CA called NeoGuide Systems is notable for its commitment to a NOTES-enabling imaging systems. They’ve developed a robotic endoscope that they have adapted to NOTES technology. (This robotic technology was originally developed for use in colonoscopies, but developers have shifted it away from this toward NOTES.)

These endoscopes can robotically rise up like a cobra -- automatically, and can serve as a weight-bearing platform from which to deploy other needed instruments. So, from an instrumentation standpoint, this is a good illustration on how there’s emerging industry buy in to developing/adapting new technology.

What’s your estimation of how the evolution of NOTES will develop in terms of the obstacles that surgeons must deal with to advance its procedures and techniques?

For one thing, I don’t think surgery is just going to turn off laparoscopy and turn on NOTES. There are presently signs that a hybrid period is emerging. In some instances, surgeons are using traditional endoscopy along with aspects of NOTES to gain access with less invasiveness than could be afforded merely by older laparoscopic methodologies.

And there are other variations. For example, instead of placing ports through the abdominal wall as we now do in laparoscopic surgery, there are groups working on putting a single port through the umbilicus to accommodate multiple instruments simultaneously. This is being called Natural Orifice Trans Umbilical Surgery, or NOTUS. An example of key, enabling innovation in this area is an access port by SurgiQuest, Inc. where the typical valves found in access ports have been removed and instead utilizes an “Air-Seal” technology to seal the device, no matter how many instruments are inserted through it.

Also, regarding the traversing some of the anatomical boundaries proposed for NOTES procedures, punctures in some of these areas (for example, the stomach wall) are currently considered to be potential high morbidity complications of routine laparoscopy…

You see, the act of passing an instrument from inside the rectum, or stomach, which are not sterile areas, into the abdominal cavity (a sterile area) carries with it some inherent risks - transmitting the bacteria to sterile areas and causing what could become a life-threatening complication. Further, reliable closure of these access areas must be possible, and herein lies another area where medical device developers are working fervently.

Atop that, there is also emphasis on finding ways to move non-target organs and tissues out of the way, without using incisions through which to pass instruments. To this end, I have been exploring the use of magnetic forces — placing magnetically permeable elements inside hollow organs or in the abdominal cavity and on the exterior body wall as a means of retracting tissues without any of the retractor-device components being present in the abdominal cavity proper. Other groups are also exploring the use of magnetism in similar ways.

What if NOTES never really gets off the ground? Would all the efforts be in vain?

Well, one way to look at it is: In many ways, minimally invasive surgery is not so minimally invasive. But even if NOTES doesn’t ever gain the traction that many of us now envision, then at some of the techniques that we’ve learned during the developmental phase of NOTES could be incorporated into routine laparoscopy, thus making the term minimally invasive less oxymoronic.