LENGTHENING BOWEL ENDOSCOPICALLY: HYDROGEL-ENABLED ENDOSCOPIC SPRING-MEDIATED DISTRACTION ENTEROGENESIS

21 We evaluated the feasibility to lengthen small bowel endoscopically utilizing a spring
22 device constrained by an engineered, slow biodegrading, hyaluronan and elastin-like protein
23 (HELP) hydrogel as a potential treatment for short bowel syndrome. While we previously
24 demonstrated that the HELP hydrogel could provide device confinement and enable non-invasive
25 device removal, here we demonstrate that the HELP hydrogel can also be designed to be
26 catheter-injectable while still being stiff enough to achieve device confinement.
27 Six pigs underwent endoscopic spring-mediated distraction enterogenesis (ESMDE), the
28 lengthening of existing intestine using axial mechanical force. A compressed spring that was
29 encapsulated in gelatin was placed into pig jejunum via enterotomy. The spring was confined on
30 each end by endoscopic catheter-injection of HELP gel into the intestinal submucosa to cause
31 transient luminal narrowing. The gelatin capsule rapidly biodegrades to deploy the spring, while
32 the HELP gel slowly biodegrades to transiently constrain the device, applying tension to the bowel
33 segment. On postoperative day 7, of the 6 pigs that underwent ESMDE, 4 had successful bowel
34 lengthening, up to 172% of the initial length. None of the animals experienced any complications
35 such as obstruction or perforation, and there were no mortalities.
36 In this proof-of-concept study, we demonstrate that a hydrogel can be designed with the
37 appropriate catheter-injection properties, stiffness, and biodegradation rate to achieve hydrogel
38 enabled, endoscopic spring-mediated distraction enterogenesis, making it a possible future
39 treatment for short bowel syndrome.