Shijie He1,2,3,4, Dara A Azar1,2,3,4, Farid Nasr Esfahani1,2,3,4, Golara A Azar5, Tarek Shazly6, Nima Saeidi1,2,3,4. 1. Division of Gastrointestinal and Oncologic Surgery, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA. 2. Center for Engineering in Medicine and Surgery, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA. 3. Shriners Hospital for Children, Boston, MA, USA. 4. Harvard Medical School, Boston, MA, USA. 5. Department of Electrical Engineering and Computer Sciences, University of California Los Angeles, Los Angeles, CA, USA. 6. Department of Mechanical Engineering, University of South Carolina, Columbia, SC, USA.
Abstract
BACKGROUND: Gut stiffening caused by fibrosis plays a critical role in the progression of inflammatory bowel disease (IBD) and colon cancer. Previous studies have characterized the biomechanical response of healthy and pathological gut, with most measurements obtained ex vivo. METHODS: Here, we developed a device and accompanying procedure for in vivo quantification of gut stiffness, termed mechanoscopy. Mechanoscopy includes a flexible balloon catheter, pressure sensor, syringe pump, and control system. The control system activates the balloon catheter and performs automated measurements of the gut stress-strain biomechanical response. RESULTS: A gut stiffness index (GSI) is identified based on the slope of the obtained stress-strain response. Using a colitis mouse model, we demonstrated that GSI positively correlates with the extent of gut fibrosis, the severity of mucosal damage, and the infiltration of immune cells. Furthermore, a critical strain value is suggested, and GSI efficiently detects pathological gut fibrotic stiffening when the strain exceeds this value. CONCLUSIONS: Based on these results, we envision that mechanoscopy and GSI will facilitate the clinical diagnosis of IBD.
BACKGROUND: Gut stiffening caused by fibrosis plays a critical role in the progression of inflammatory bowel disease (IBD) and colon cancer. Previous studies have characterized the biomechanical response of healthy and pathological gut, with most measurements obtained ex vivo. METHODS: Here, we developed a device and accompanying procedure for in vivo quantification of gut stiffness, termed mechanoscopy. Mechanoscopy includes a flexible balloon catheter, pressure sensor, syringe pump, and control system. The control system activates the balloon catheter and performs automated measurements of the gut stress-strain biomechanical response. RESULTS: A gut stiffness index (GSI) is identified based on the slope of the obtained stress-strain response. Using a colitis mouse model, we demonstrated that GSI positively correlates with the extent of gut fibrosis, the severity of mucosal damage, and the infiltration of immune cells. Furthermore, a critical strain value is suggested, and GSI efficiently detects pathological gut fibrotic stiffening when the strain exceeds this value. CONCLUSIONS: Based on these results, we envision that mechanoscopy and GSI will facilitate the clinical diagnosis of IBD.
Authors: Vivek Krishna Pulakazhi Venu; Laurie Alston; Mircea C Iftinca; Yi-Cheng Tsai; Matthew Stephens; Vineetha Warriyar; Sonia Rehal; Grace Marie Hudson; Holly Szczepanski; Pierre-Yves von der Weid; Christophe Altier; Simon A Hirota Journal: Am J Physiol Gastrointest Liver Physiol Date: 2021-07-21 Impact factor: 4.052
Authors: Laura A Johnson; Eva S Rodansky; Kay L Sauder; Jeffrey C Horowitz; Justin D Mih; Daniel J Tschumperlin; Peter D Higgins Journal: Inflamm Bowel Dis Date: 2013-04 Impact factor: 5.325