By Deborah Borfitz
November 17, 2020 | By making colonoscopies semi-autonomous, a global team of researchers hopes to eliminate some of the key drawbacks of the procedure that have made it highly unpopular with patients. Unless individuals are completely anesthetized, they frequently report pain because colonoscopy is a difficult skill to master, says Bruno Scaglioni, a postdoctoral research fellow working in the STORM Lab UK at the University of Leeds. A colonoscopy is a “very clinician-dependent procedure… more experienced clinicians tend to be better at driving the endoscope.”
Certain populations, including people with inflammatory bowel disease, are at higher risk of procedural complications such as intestinal perforation. The anesthesia itself comes with a whole other set of hazards that increase with age, says Scaglioni. Many people are simply afraid of “going under.”
It’s useful to get “live feedback” from alert patients while performing a colonoscopy so clinicians know who is responding well and able to independently move from a supine to side position—or if the endoscope is causing trauma, and thus pain, to tissues, he says. The goal with the research team’s newly developed method, which relies on a robot to navigate a magnetic flexible endoscope, is to have patients awake as well as pain-free during the procedure.
The approach brings closer the prospect of an intelligent robotic system capable of guiding instruments to precise locations in the body to take biopsies or allow internal tissues to be examined, according to study co-author Keith Obstein, director of the STORM Lab USA at Vanderbilt University. Software packages and algorithms could be implemented on the hardware to turn the magnetic flexible endoscope into an autonomous diagnostic and therapeutic device. The STORM Lab already has work underway to stabilize the endoscope to make it potentially more efficient at removing lesions of pathology.
Obstein and Scaglioni are among co-authors of a study, recently published in Nature Medicine Intelligence (DOI: 10.1038/s42256-020-00231-9), which describes this promising alternative approach to having clinicians manually steer a colonoscope to its destination. Instead, a small, capsule-shaped device tethered to a narrow cable gets inserted into the anus and guided into place by a magnet on a robotic arm positioned over the patient.
The breakthrough could allow for a broader array of healthcare professionals to do colonoscopies and potentially do so in a clinician’s office or rural care settings without a dedicated in-house endoscopist. That is, Obstein says, “if we’re able to demonstrate that patients can avoid the need for sedation or anesthesia and feel more comfortable with the magnetic flexible endoscope as the mechanism for their colon exploration.”
Well-trained nurses or staff technologists could be responsible for the technical aspects of the procedure in concert with the magnetic flexible endoscopy, with a supervisory endoscopist or gastroenterologist overseeing them either on premise or remotely, Obstein says. Of note is that the long list of equipment, staff and space needs shortens considerably if no sedation is needed to do the procedure.
Colonoscopies have been done the same way for decades, and development of the potentially more accessible and palatable system has been marked by three developmental milestones over the last 12 years, says Scaglioni. The first was realization that the magnetic endoscope needed a robot to handle the navigational problem for clinicians so they could focus on what the endoscopic images were showing them. The second big step was to give clinicians a way to visualize the whereabouts of the endoscope when it was inside patients’ colon.
Finally, the research team figured out the device needed to offer different levels of robotic assistance, says Scaglioni. When non-expert staff were given full and direct control of the robot via a joystick in a laboratory simulation, 42% were unsuccessful at moving the capsule to a target spot in the colon of an anesthetized pig within 20 minutes. A separate test found that operating the magnetic endoscope was less physically and mentally taxing for participants with the addition of robotic assistance when compared to a traditional colonoscope.
A successful colonoscopy is typically defined by the ability to reach the cecum (the first part of the colon after the small bowel) and is tied to operator experience, Scaglioni says. Previous studies have found that the success rate increases as more colonoscopies are performed and only rises above 90% once about 250 procedures have been done.
Learning to do a colonoscopy takes a great deal of training via a three-year fellowship, says Obstein. The magnetic endoscope approach could theoretically reduce the learning curve by eliminating the complexity related to steering the device through the colon. A wide range of providers, if well trained, could perhaps do more consistent, high-quality exams in a shorter time period while leaving the assessment and diagnosis of pathology—and making critical decisions in a supervisory context—as the only cognitive burden on gastroenterologists/endoscopists.
With funding from Cancer Research UK, the first-in-human trial of the robot-assisted device is planned for launch in October 2021 at the University of Leeds and will enroll 17 healthy volunteers to assess if the technology can successfully reach and examine the cecum, which has thus far been demonstrated only in animals and human cadavers, says Scaglioni. Secondary outcomes include safety of the device and patient satisfaction with the procedure, including level of discomfort, based on real-time feedback from the non-sedated, non-anesthetized participants.
Multi-center trials are expected to follow, and the global sites will include Vanderbilt University and the University of Leeds. Goals of later-stage studies include assessing if trainees can use the magnetic flexible endoscope system to become competent in a quicker manner while also measurably improving the quality and safety of the colonoscopies they perform, says Obstein.
Trials will also be conducted to evaluate the capabilities of the system when used to perform therapies, such as the removal of polyps from the colon, he continues. The magnetic flexible endoscope can be used in tandem with standard endoscopic instruments such as biopsy forceps, snares for removing polyps, injection needles, and clips.
“The only limitation of our technology might be with patients who have a very high BMI because we have two magnets and they must be at a distance where they can interact with each other,” Scaglioni says. The threshold will be related to abdominal girth, not weight, and will need to be established by later-stage clinical trials.
Based on colonoscopy volume, the U.S.—where about 15 million of the procedures are done annually—is the big market being targeted, Scaglioni says. “In Europe it is much more common to have an initial screening with a fecal blood test and then a colonoscopy only if there is something wrong.” Roughly four million colonoscopies are performed in Europe every year.
None of the current alternatives to traditional colonoscopies have the same potential as the magnetic flexible endoscope, Scaglioni adds. Robotic actuation of conventional endoscopes doesn’t address the pain and reprocessing issues, and wireless capsule endoscopes just record images. Moreover, internally triggered mechanisms introduce design complexity that prevents substantial cost reduction—a paramount concern of healthcare systems everywhere.
The goal of many professional societies was to have 80% of people eligible for a colonoscopy screened by 2018, says Obstein, but as of 2020 the national screening rate was still more than 10 percentage points shy of that target. The need for colonoscopies is also projected to rise by around 16% over the next decade, due in part to the aging population and clinical guidelines that could lower the recommended age at which screenings begin to age 40, says Obstein. The American Cancer Society has been advocating for the update based on data suggesting colorectal cancer is on the rise in people less than 50 years old.
Additionally, the pandemic has caused many people to forego standard exams as hospitals and clinics temporarily closed or began operating at reduced volume or hours in the interest of public safety, Obstein says. This has created a backlog of people needing screening and an expected uptick in colon cancer over the next five to 10 years among those who never do get their exam.
Part of the public distaste for the procedure is the prep involved, which the magnetic endoscope won’t solve. But a side project at the University of Leeds is looking into how scientists might come to the rescue of people who have a particularly hard time cleaning their bowels due to systemic conditions, diseases, or medication side effects.
But even in a perfect world where everyone is getting age-appropriately screened and technicians are performing high-quality colonoscopies with a good adenoma and polyp detection rate, system capacity issues, the upfront cost of endoscopy towers and ongoing endoscopy reprocessing fees would remain, says Obstein. The use of anesthesia also requires additional machines, monitoring, and staff—from nurses and anesthesiologists to technicians and cleaning personnel.
The per-procedure outlay for a conventional colonoscopy includes the “hidden cost” of cleaning and reprocessing the endoscopes, which run between $20,000 and $30,000 a piece to acquire, says Scaglioni. It is therefore common practice for hospitals to sterilize an endoscope after every use for around $300-$400 per cleaning. Getting them fixed if they break is an even pricier proposition.
The research team expects the cost of their single-use magnetic flexible endoscope will be “more or less” what hospitals are currently spending on reprocessing alone, Scaglioni continues. The price will depend on the camera that gets incorporated into the final marketed product, which is “the only expensive component of the device.” The current iteration uses cameras harvested from commercial endoscopes, which may or may not prove to be of sufficient quality for diagnostic purposes.
Far into the future, Obstein says he can imagine the magnetic flexible endoscope system autonomously performing colonoscopies after a nurse or technologist inserts the device into the patient. The clinician would be alerted when the endoscope gets to the cecum and begins self-exploring its way back to the anus, with the clinician serving in a supervisory capacity, and a medical team member on standby to insert biopsy forceps, snares, or other tissue sampling instruments as needed for polyp removal.
The workflow would be much like how anesthesiologists currently supervise multiple operating rooms from an out of-OR location, with in-room certified registered nurse anesthetists performing a lot of the direct patient care and technical functions, he says. Only in the envisioned scenario, a trained technologist would be at the bedside with the oversight of a supervisory endoscopist or gastroenterologist. The research team is already thinking about the possibly of having the magnetic endoscope automatically create 3D maps of the colon to ensure it gets fully inspected.
STORM Lab UK also has several other endoscope-related projects underway that are in earlier stages of development, adds Scaglioni. One involves tiny “magnetic tentacles” rather than a single endoscope controlled by magnetic coupling so the device can get to areas of the human body, including the brain and the lungs, which are difficult to access in conventional ways. The path followed by a tentacle to do a tumor ablation, bronchoscopy or other procedure would be pre-computed.
Scaglioni says he is even more excited about adapting the technology to pancreatic endoscopy, given that pancreatic tumors are one of the most aggressive and hard-to-find cancers treated by oncologists. “The survival rate is extremely low and one of the reasons is that endoscopy of the pancreas is very difficult because you have to go through the stomach, into the first part of the small intestine, and then make a U-turn and go through a very tiny valve to find [the organ]. A very accurate magnetic guide of a tiny endoscope has, in that case, the potential to save a lot of lives.”