Novel accessory designed to facilitate complex endoscopic mucosal resection
Eric M Pauli MD, Joshua S Winder MD, Vamsi V Alli MD
Penn State College of Medicine, Penn State Hershey Medical Center, Hershey, PA.
The GripTract-GI endoscopic tissue manipulator (Figure 1) is a novel cap-based endoscopic accessory designed to facilitate complex endoscopic mucosal resection. The goal of this study is to evaluate the efficacy of the manipulator during en bloc removal of simulated colorectal mucosal lesions in benchtop and preclinical studies.
The primary goals of the platform include; facilitating safe endoscopic submucosal dissection (ESD) methods, broadening application of ESD for clinicians with less extensive training, and improving ESD outcomes. This approach may enable organ sparing surgery in colorectal lesions traditionally deemed endoscopically unresectable. The manipulation of external “fingers” by the clinician using a simple proximal handpiece attached to the endoscope control body enables dynamic traction and countertraction of tissues facilitating electrosurgical knife use during ESD. The technology is compatible with standard colonoscopes and can be attached and removed without altering the colonoscope.
Functional prototypes utilizing this technology were developed and studied as an adjunct in removal of mucosal tissue through ESD. Wet laboratory ESD studies were first performed on porcine stomach tissue by physicians to gain familiarity with the GripTract-GI system and controls. While working with the device, physicians also discovered several unanticipated maneuvers to perform dynamic tissue retraction and to increase the degrees-of-freedom of the electrosurgery tools. These techniques were employed during preclinical porcine studies (n=10 of 14 at time of abstract), where each animal underwent one standard cap-assisted ESD and one GripTract-assisted ESD for comparison. En bloc mucosal resections of up to 6.5 cm2 were performed. Preliminary data shows that with comparable resection areas between standard and GripTract (1.98 ± 0.61 cm2 vs. 2.46 ± 0.80 cm2, p=0.65), resection speeds were also similar (5.33 ± 1.89 mm2/min. standard vs. 5.70 ± 1.55 mm2/min. GripTract, p=0.88). However, the average relative resection speed (GripTract to standard) increased over repeated procedures for each physician, and the perforation rate for GripTract was 50% of that when using standard technique.
In this first preclinical evaluation of the GripTract-GI endoscopic tissue manipulator there was specific utility of this technology to facilitate large mucosal resections. The increase in resection speed with GripTract relative to standard technique over several procedures provides preliminary evidence for a faster learning curve and possible expansion of the pool of clinicians capable of offering ESD – though more studies are warranted before final conclusions are made. Although initially intended for colorectal lesions, this platform has future potential for upper gastrointestinal endoscopy interventions, such as in esophageal or gastric ESD.