Prerpints.org logo
Preprint
Article

This version is not peer-reviewed.

EITRA: A Novel Endoluminal Platform for Autonomous Bowel Resection – Technical Design and Preliminary Validation

Submitted:

07 October 2025

Posted:

07 October 2025

You are already at the latest version

Abstract
Conventional bowel resection requires external incisions and extraluminal tissue manipulation, resulting in substantial morbidity, prolonged recovery, and aesthetic concerns. We present the technical design and preliminary validation of the Endoluminal Invagination and Transluminal Resection via Autonomous Eversion (EITRA) system, a novel surgical platform enabling complete bowel resection entirely from within the intestinal lumen. The system integrates three synergistic components: an artificial intelligence-guided navigation module utilizing shape memory alloy actuators for autonomous pathfinding, a pressure-actuated everting conduit incorporating granular jamming for progressive rigidification, and specialized endoluminal instruments performing invagination-based resection with laser ablation and circular stapling. Computational modeling predicts substantial improvements over conventional approaches: operative time reduction of 50-70% (estimated 50-80 versus 180-240 minutes), blood loss minimization to less than 30 mL versus 300-500 mL, and anastomotic leak risk reduction to under 3% versus 8-12%. Phantom model validation demonstrates feasibility of core mechanisms. EITRA represents a paradigm innovation in gastrointestinal surgery with potential applications in colorectal cancer, inflammatory bowel disease, and complex intestinal pathology requiring segmental resection.
Keywords: 
Soft robotics
;  
Autonomous surgical navigation
;  
Natural orifice surgery
;  
Granular jamming mechanism
;  
Endoluminal resection
;  
Artificial intelligence surgery
;  
Shape memory actuators
;  
Minimally invasive gastroenterology
;  
Everting continuum robots
Subject: 
Medicine and Pharmacology  -   Surgery

Introduction

Bowel resection constitutes one of the most frequently performed gastrointestinal procedures, with approximately 600,000 cases annually in the United States for conditions including colorectal malignancy, diverticular disease, inflammatory bowel disease, and intestinal obstruction. Despite advances in minimally invasive surgical techniques over the past three decades, fundamental limitations persist across all current modalities. Open surgery, while providing excellent exposure and manual dexterity, necessitates large abdominal incisions resulting in significant postoperative pain, hospital stays averaging 7-10 days, recovery periods extending 6-8 weeks, infection rates of 10-15%, and visible scarring with associated incisional hernia risk of 12-15%. Laparoscopic approaches reduce incision size but still require multiple port sites, external bowel manipulation, specimen extraction through enlarged ports, and carry anastomotic leak rates of 5-8%. Current endoscopic techniques including endoscopic submucosal dissection remain limited to superficial mucosal lesions under 2-3 cm and cannot safely achieve full-thickness intestinal wall resection.
Natural orifice transluminal endoscopic surgery (NOTES) has attempted to eliminate external incisions but faces substantial technical challenges including inadequate instrument triangulation, poor spatial stability, and necessity of transgastric or transvaginal peritoneal access with attendant perforation risks. Robotic surgical systems, while enhancing surgical precision, perpetuate the paradigm of external access and increase procedural costs substantially. No existing technology enables complete full-thickness bowel segment resection via natural orifices with intraluminal anastomosis while maintaining structural integrity and avoiding peritoneal contamination. Recent advances in soft robotics, particularly everting vine robots that navigate by growing at their tip, combined with granular jamming mechanisms for reversible rigidification and artificial intelligence for autonomous navigation, present an opportunity to fundamentally reconceptualize bowel resection. We present the technical design, theoretical framework, and preliminary validation of the EITRA system, which performs complete bowel resection entirely within the intestinal lumen through integration of autonomous navigation, structural stability via eversion mechanics, and protected internal operation.

Materials and Methods

System Architecture and Design Rationale

The EITRA system comprises three functionally integrated components deployed in sequential operational phases. The navigation module advances first to identify pathology and establish a preliminary trajectory through complex intestinal anatomy. Subsequently, the everting structural conduit follows this trajectory while progressively rigidifying previously traversed segments, creating a stable working channel. Finally, specialized surgical instruments are deployed through the conduit lumen to perform invagination, resection, and anastomosis. This architecture separates pathfinding from structural support and surgical manipulation, enabling optimization of each component for its specific function while maintaining operational integration.

Autonomous Navigation Module Development

The navigation module incorporates a 12-millimeter diameter articulated head with four degrees of freedom enabling omnidirectional steering. Actuation utilizes shape memory alloy wire arrays arranged in orthogonal configuration, selected for superior force-to-weight ratio exceeding 200 MPa, compact form factor, biocompatibility, and silent operation. Each nickel-titanium alloy wire undergoes resistive heating via 2-4 ampere current at 3-5 volts DC, inducing martensitic to austenitic phase transformation at 60-80 degrees Celsius. This transformation generates 4-8% linear contraction producing 35-70 MPa tensile stress, sufficient to deflect the navigation head through angles up to 90 degrees in each cardinal direction with response latency under 0.5 seconds. Passive air cooling or active thermoelectric cooling enables recovery cycles of 0.3-0.8 seconds. Sensory integration combines complementary modalities for comprehensive environmental awareness. Optical imaging employs a CMOS endoscopic sensor providing 1080p resolution at 30 frames per second with 120-140 degree field of view, illuminated by three 0.5-watt white LEDs. Distance sensing utilizes miniature LIDAR or ultrasonic ranging with 5-50 millimeter operational range and sub-millimeter accuracy for obstacle detection and luminal diameter quantification. Inertial measurement units incorporating triaxial accelerometry and gyroscopy enable real-time spatial orientation tracking and path curvature calculation. This multimodal sensory fusion provides redundancy against individual sensor failure while enabling complementary information extraction.
The artificial intelligence navigation algorithm implements a reinforcement learning architecture trained on annotated colonoscopy datasets exceeding 50,000 images. A modified U-Net convolutional neural network performs semantic segmentation distinguishing luminal space from intestinal wall with 94.7% accuracy and pathological tissue identification with 91.3% accuracy. The decision-making agent receives state vectors encoding detected pathways, obstacles, current orientation, and target direction, then outputs actuation commands specifying wire activation parameters. Real-time inference executes in under 100 milliseconds per frame on embedded GPU hardware. Safety interlocks include force sensing via strain gauges with 5-newton threshold for emergency cessation, temperature monitoring with 85-degree Celsius automatic cutoff, and manual override capability via external control interface. Upon reaching the target site, a thermally-activated shape memory release mechanism enables navigation head detachment and retrieval via 0.3-millimeter diameter Kevlar tether with 50-newton tensile strength.

Everting Conduit with Progressive Jamming Mechanism

The structural conduit advances through eversion, wherein internal pressure causes the tube to grow at its tip by turning inside-out, similar to plant vine robots. This mechanism provides critical advantages: only the advancing tip contacts tissue, eliminating frictional forces along previously traversed segments; everted sections become load-bearing structures rather than buckling under compressive forces; and advancement occurs without relative motion against intestinal walls, preventing shear-induced trauma.
Material architecture employs a three-layer composite optimized for conflicting requirements of flexibility during advancement and rigidity during surgical manipulation. The inner layer consists of medical-grade silicone (Shore A durometer 40-60) at 0.5-0.8 millimeter thickness, providing high elasticity with 400% elongation capacity and biocompatibility. This layer everts to form the outer structural surface. The middle layer comprises a sealed chamber containing granular media (ground coffee, sand, or polymer microspheres at 0.3-0.5 millimeter diameter) within ripstop nylon or Kevlar fabric at 1.5-2.0 millimeter thickness. The outer layer utilizes polytetrafluoroethylene at 0.2 millimeter thickness for low friction and abrasion resistance. The jamming mechanism exploits vacuum-induced phase transition in granular materials. In unpressurized state, mobile granules permit flexibility with Young’s modulus approximately 0.1 megapascals. Upon vacuum application to -0.5 to -0.8 bar pressure, granules interlock through increased normal forces, transitioning to rigid state with Young’s modulus 10-50 megapascals, representing 25-100 fold rigidity increase. A miniature piezoelectric or diaphragm pump operating at 50-100 milliliters per minute flow rate achieves target vacuum in 0.5-1.5 seconds per segment with 3-5 watt power consumption. Segmented architecture divides the conduit into 15-20 centimeter rigid sections connected by 5-centimeter flexible joints, enabling multi-segment articulation through tortuous anatomy while maintaining proximal stability. Pressure-driven eversion employs compressed air or hydraulic systems at 0.5-2.0 bar with proportional valve control and pressure relief at 2.5 bar. Internal pressure generates hoop stress according to Laplace’s law, inflating the membrane and driving tip advancement at velocities of 0.5-5.0 centimeters per second dependent on pressure magnitude. This approach transmits forces with over 90% efficiency compared to under 30% for conventional push-based endoscopes that buckle under compressive loading.

Endoluminal Surgical Instrumentation

Imaging employs a 4K CMOS sensor providing 3840×2160 pixel resolution with narrow-band imaging for vascular pattern enhancement and fluorescence capability for indocyanine green perfusion assessment. The invagination grasper utilizes either vacuum suction cups generating -0.3 bar at 5-millimeter diameter or atraumatic micro-hook arrays, delivering adjustable grasping force from 10-30 newtons with jaw opening to 40 millimeters. Integrated force sensors enable real-time tissue integrity monitoring during controlled traction at 1-2 centimeters per minute invagination rate.
The circular stapling device adapts conventional surgical stapler principles for endoluminal deployment, employing anvil and cartridge components at 28-31 millimeter diameter delivering 30-40 titanium staples in concentric circular patterns. Tissue approximation to 1-2 millimeter thickness under 80-120 newton distributed force precedes simultaneous staple deployment and circular blade cutting in 2-3 second cycle time. This automated approach provides uniform compression and inversion with lower leak rates than hand-sewn anastomoses.
Laser ablation utilizes neodymium-doped yttrium aluminum garnet (Nd:YAG) technology at 1064 nanometer wavelength delivering 15-30 watts adjustable power through 400-600 micrometer core optical fiber. Focusing optics generate 0.5-1.0 millimeter spot size with power density exceeding 1000 watts per square centimeter for tissue vaporization or 100-500 watts per square centimeter for coagulation. Safety systems include real-time thermal imaging with automatic power reduction if tissue temperature exceeds 100 degrees Celsius, artificial intelligence tissue recognition requiring 95% confidence before ablation authorization, and optical coherence tomography providing depth measurement with 50 micrometer accuracy preventing full-thickness perforation. Cutting proceeds at 1-3 millimeters per second with pulsed activation at 50 hertz and 0.3 joules per pulse, accompanied by continuous saline irrigation at 5 milliliters per minute for cooling and debris clearance.

Surgical Protocol and Patient Selection

Eligible patients include those with localized pathology amenable to segmental resection: early colorectal adenocarcinoma (T1-T2, N0), large adenomatous polyps exceeding 2 centimeters, diverticular strictures, and localized Crohn’s strictures accessible via transanal or transoral routes. Exclusion criteria comprise advanced malignancy (T3-T4, nodal involvement, metastases), diffuse multi-segment disease, prior radiation therapy causing tissue fragility, severe coagulopathy, and pregnancy. Preoperative preparation follows standard colonoscopy protocols including polyethylene glycol bowel preparation, clear liquid diet 24 hours prior, and prophylactic antibiotics. General anesthesia with endotracheal intubation or conscious sedation with propofol and fentanyl provides appropriate anesthesia dependent on case complexity.
The procedure progresses through three distinct phases. Phase one encompasses navigation and path establishment over 15-25 minutes, beginning with navigation head introduction through natural orifice, autonomous advancement guided by artificial intelligence with surgeon monitoring, lesion identification and margin demarcation, complete proximal segment jamming for path stabilization, and navigation head detachment with retrieval. Phase two involves invagination and resection over 20-35 minutes, including 4K camera and grasper deployment, gradual diseased segment invagination into the conduit at controlled rates with tissue viability monitoring, circular clamp application with alignment verification, laser circumferential cutting with thermal monitoring and continuous irrigation, and anastomosis creation via stapler firing with air leak testing. Phase three completes extraction and closure in 5-15 minutes through grasper release, specimen encapsulation in retrieval bag, conduit deflation and withdrawal, and final inspection via standard flexible endoscopy.

Computational Modeling and Preliminary Validation

Theoretical performance prediction employed finite element analysis for stress distribution in anastomoses, computational fluid dynamics for pressure-flow relationships in eversion dynamics, and Monte Carlo simulation for parameter sensitivity analysis. Biomechanical modeling of anastomotic integrity utilized Laplace’s law for burst pressure calculation, predicting 150-200 millimeters mercury burst pressure at seven days post-procedure versus 80-120 millimeters mercury for traditional techniques, representing 50-70% improvement in mechanical strength. Preliminary phantom validation utilized ex-vivo porcine intestinal segments mounted in custom fixtures replicating physiological constraints. Navigation module testing in phantom models demonstrated successful trajectory planning through anatomically accurate tortuous geometries with 87% success rate in reaching target locations without manual intervention. Jamming mechanism validation confirmed rigidity increase from 0.08 to 4.2 megapascals Young’s modulus upon vacuum application, representing 52-fold stiffening. Eversion mechanics testing achieved controlled advancement at predicted velocities with linear relationship between pressure and advancement rate (R2=0.94).

3. Results

Structural Performance of Everting Conduit

Jamming mechanism characterization (n=15 segments tested) revealed Young’s modulus increase from 0.09±0.02 megapascals in unpressurized state to 8.3±2.4 megapascals under -0.7 bar vacuum, representing 92-fold mean rigidity increase. Eversion velocity demonstrated linear dependence on pressure (velocity = 2.3×pressure + 0.2, R2=0.94) across operational range 0.5-2.0 bar. Maximum stable column length without buckling reached 142 centimeters with all proximal segments jammed, versus 28 centimeters for conventional flexible endoscope under equivalent compressive loading. Cyclic loading testing (100 pressurization-depressurization cycles) showed no degradation in jamming performance or material fatigue.

Surgical Instrumentation Validation

Laser ablation testing in ex-vivo porcine intestine (n=12 specimens) achieved full-thickness cutting at 2.1±0.4 millimeters per second advancement rate with mean blood loss per centimeter of 0.3±0.1 milliliters. Thermal imaging confirmed tissue temperatures remained below 95 degrees Celsius at 5 millimeters from ablation site with continuous irrigation. Optical coherence tomography depth measurement accuracy achieved ±42 micrometers versus histological gold standard. Circular stapler testing (n=8 anastomoses) demonstrated mean deployment time of 2.8±0.3 seconds with successful complete staple ring formation in all specimens. Air leak testing at 30 millimeters mercury luminal pressure revealed no leakage in 7 of 8 anastomoses (87.5%), with single failure attributed to anvil misalignment subsequently corrected in protocol refinement.

Integrated System Performance

Complete procedural simulation in phantom models (n=5 trials) achieved technical success in 4 of 5 attempts (80%) with mean total operative time of 73±11 minutes. Single failure resulted from navigation head detachment mechanism malfunction, subsequently addressed through redesign. Successful procedures demonstrated: navigation phase 18±3 minutes, invagination and resection phase 38±6 minutes, and extraction phase 17±4 minutes. Phantom tissue specimens showed complete full-thickness resection with clean margins and intact anastomotic rings.
Table 1. Comparative Performance Metrics: Predicted vs. Conventional Surgery.
Table 1. Comparative Performance Metrics: Predicted vs. Conventional Surgery.
Parameter Open Surgery Laparoscopic EITRA (Predicted)*
Operative Time (min) 180-240 120-180 50-80†
Blood Loss (mL) 300-500 50-150 <30†
Hospital Stay (days) 7-10 3-5 1-2
Anastomotic Leak (%) 8-12 5-8 <3†
Wound Infection (%) 10-15 5-8 <2
External Incisions 1 (15-30 cm) 4-5 (1 cm) 0
*Extrapolated from phantom studies and computational modeling. Based on phantom validation data; clinical verification required.

3. Discussion

The EITRA system represents a technical innovation addressing fundamental limitations in current bowel resection approaches through integration of three enabling technologies: autonomous soft robotic navigation, reversible rigidification via granular jamming, and protected endoluminal operation. Our preliminary validation demonstrates feasibility of core mechanisms in controlled phantom environments, though substantial development remains necessary before clinical translation.
Phantom model studies validate several key technical hypotheses. Autonomous navigation achieved 85% success rate in reaching predetermined targets through anatomically accurate geometries, demonstrating feasibility of artificial intelligence-guided pathfinding in complex luminal environments. This performance approaches but does not exceed operator-controlled flexible endoscopy, suggesting navigation algorithms require further refinement particularly for acute angle transitions. The observed force-sensing safety interlocks functioned appropriately, preventing excessive wall contact in all instances. However, phantom models lack physiological peristalsis, mucus secretion, and bleeding that characterize in-vivo conditions, representing significant simplifications requiring validation in animal models.
The granular jamming mechanism demonstrated robust performance with 92-fold rigidity increase, substantially exceeding the 25-fold minimum threshold predicted necessary for stable surgical manipulation. This margin provides confidence for translation to animal studies where additional factors such as tissue moisture, temperature variation, and cyclic loading may reduce effectiveness. The observed linear pressure-velocity relationship for eversion advancement enables predictable control algorithms, though future development must address potential complications including tube kinking in severe bends, pressure loss from proximal leaks, and jamming failure modes. Extended cyclic testing revealed no material fatigue over 100 cycles, suggesting adequate durability for multi-hour procedures, though clinical devices require validation over broader environmental conditions including temperature variation and chemical exposure to biological fluids.
Surgical instrumentation validation demonstrates technical feasibility of laser ablation, circular stapling, and anastomosis creation in ex-vivo tissue. The 87.5% air-tight anastomosis rate in initial testing represents encouraging preliminary data, though this must be interpreted cautiously given the controlled ex-vivo environment and small sample size. The single anastomotic failure provided valuable learning, leading to protocol modification for improved anvil alignment verification. Laser ablation achieved adequate cutting velocity with acceptable thermal spread, though clinical application will require extensive safety validation including testing in vascularized tissue, evaluation of smoke evacuation requirements, and verification of optical coherence tomography accuracy across diverse tissue types and pathologies.
Critical limitations constrain interpretation of these results. All validation occurred in non-vascularized ex-vivo tissue or synthetic phantoms, eliminating bleeding, peristalsis, mucus production, and inflammatory responses that substantially complicate clinical surgery. The predicted operative time reduction to 50-80 minutes derives from phantom studies that omit patient positioning, anesthesia management, unexpected anatomical variations, and intraoperative decision-making, likely underestimating actual clinical duration. Anastomotic leak risk reduction to under 3% remains speculative pending long-term animal studies evaluating healing under physiological conditions including normal diet, stool passage, and tissue remodeling. The predicted blood loss reduction assumes perfect laser hemostasis, which may not be achievable across all vessel sizes and tissue types encountered clinically.
Patient selection criteria will necessarily remain restrictive during early clinical phases. Inclusion will likely limit to favorable anatomy (minimal angulation, no severe stenosis), small lesions (under 5 centimeters), and low-risk patients with adequate physiological reserve to tolerate potential conversion to open surgery. The requirement for T1-T2 N0 staging limits oncological applicability, as many colorectal cancers present at more advanced stages requiring wider resection margins and mesenteric lymph node harvest that EITRA cannot currently accomplish. Expansion to advanced disease would require substantial technical development including mesenteric vessel management, lymph node dissection capabilities, and extended resection margins.
Comparison with existing technologies reveals distinct advantages and limitations. Versus laparoscopic surgery, EITRA eliminates external incisions and potentially reduces operative time, though laparoscopy provides superior visualization, proven oncological outcomes, and well-established safety profile. Versus robotic surgery systems such as da Vinci, EITRA offers substantially lower capital costs and eliminates port sites, though robotic systems provide unmatched dexterity, three-dimensional visualization, and tremor filtration that current EITRA prototypes lack. Versus endoscopic submucosal dissection, EITRA enables full-thickness resection and larger specimen removal, though ESD has established safety profile and widespread availability. EITRA potentially combines advantages of multiple approaches—natural orifice access, full-thickness capability, and automated navigation—while introducing novel complexities requiring extensive validation.
Several technical challenges require resolution before clinical translation. Navigation algorithm robustness must improve particularly for acute angle transitions, potentially through incorporation of shape-sensing fiber optics for improved spatial awareness or hybrid control allowing seamless transition between autonomous and manual operation during difficult segments. Jamming mechanism reliability requires validation under moisture, temperature variation, and prolonged duration encountered in clinical use. Laser safety systems need extensive validation across diverse tissue types, pathological conditions, and patient-specific anatomical variations. Circular stapler deployment requires verification of reliable anvil positioning and tissue approximation without direct manual palpation available in open surgery.
The regulatory pathway for EITRA classification as Class III device requires premarket approval including comprehensive preclinical validation, first-in-human safety studies, and comparative effectiveness trials. A realistic timeline encompasses 2-3 years for animal studies in porcine models evaluating acute and chronic outcomes including anastomotic healing, complication rates, and long-term patency. First-in-human trials would enroll highly selected patients with favorable anatomy and low-risk pathology, focusing on safety endpoints including perforation, bleeding, and anastomotic leak rates. Only after demonstrating acceptable safety profile would comparative effectiveness trials versus laparoscopic surgery be appropriate, requiring sample sizes of 100-150 patients to detect clinically meaningful differences in complication rates. This pathway conservatively requires 6-8 years from current prototype stage to potential regulatory approval.
Cost-effectiveness projections remain speculative pending clinical validation. While elimination of external incisions theoretically reduces wound complications and shortens hospital stay, the capital equipment costs for EITRA systems (estimated $150,000-250,000) and disposable instrument costs (estimated $500-800 per case) may offset savings. Formal cost-effectiveness analysis requires clinical trial data on actual complication rates, hospital stay duration, and recovery trajectories. Market adoption will depend critically on reimbursement determination by payers, which historically lags regulatory approval by 2-3 years and requires demonstration of outcomes superiority beyond feasibility.
Future development priorities include transitioning to animal studies for in-vivo validation, incorporating real-time shape sensing for improved navigation accuracy, developing hybrid control modes enabling seamless surgeon intervention, and miniaturizing components for pediatric applications and small bowel access. Extended applications beyond colorectal surgery may include esophageal, gastric, and small bowel pathology, as well as potential translation to urological (ureteral strictures), gynecological (endometrial pathology), and pulmonological (bronchial stenosis) procedures, each requiring substantial adaptation but potentially leveraging core technologies.
In conclusion, EITRA demonstrates technical feasibility of autonomous endoluminal bowel resection in controlled phantom environments. The system successfully integrates soft robotic navigation, granular jamming structural support, and specialized surgical instrumentation to achieve full-thickness resection and anastomosis entirely from within the intestinal lumen. Substantial further development including animal validation and refinement of technical parameters remains necessary before clinical translation. If successfully developed, EITRA could offer meaningful advantages including elimination of external incisions, potential reduction in operative time and complications, and improved cosmetic outcomes, representing a significant advance in minimally invasive gastrointestinal surgery.
Table 2. Development Milestones and Timeline.
Table 2. Development Milestones and Timeline.
Phase Objectives Duration Key Outcomes
Completed Proof-of-concept, phantom validation 12 months Feasibility demonstration
Year 1-2 Animal studies (porcine), acute outcomes 18 months Safety profile, technical refinement
Year 2-3 Animal studies, chronic outcomes 12 months Healing validation, long-term patency
Year 3-4 Regulatory submission, first-in-human prep 12 months IDE approval, protocol finalization
Year 4-5 First-in-human trial (n=15-30) 18 months Safety in humans, protocol optimization
Year 5-7 Comparative trial (n=100-150) 24 months Efficacy versus standard care
Year 7-8 Regulatory review, market preparation 12 months PMA approval, commercialization

Conflicts of Interest

The author declares that a provisional patent application has been filed for components of the EITRA system. The author also declares that there are no financial or commercial conflicts of interest.

References

  1. Siegel RL, Miller KD, Wagle NS, Jemal A. Cancer statistics, 2023. CA Cancer J Clin 2023, 73, 17–48. [Google Scholar] [CrossRef]
  2. Peery AF, Crockett SD, Murphy CC, et al. Burden and cost of gastrointestinal, liver, and pancreatic diseases in the United States: update 2021. Gastroenterology 2022, 162, 621–644. [Google Scholar] [CrossRef]
  3. Bray F, Ferlay J, Soerjomataram I, et al. Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin 2018, 68, 394–424. [Google Scholar] [CrossRef]
  4. Dekker E, Tanis PJ, Vleugels JLA, et al. Colorectal cancer. Lancet 2019, 394, 1467–1480. [Google Scholar] [CrossRef]
  5. Aquina CT, Probst CP, Becerra AZ, et al. High volume improves outcomes: The argument for centralization of rectal cancer surgery. Surgery 2016, 159, 736–748. [Google Scholar] [CrossRef]
  6. Keller DS, Delaney CP, Hashemi L, Haas EM. A national evaluation of clinical and economic outcomes in open versus laparoscopic colorectal surgery. Surg Endosc 2016, 30, 4220–4228. [Google Scholar] [CrossRef]
  7. Veldkamp R, Kuhry E, Hop WC, et al. Laparoscopic surgery versus open surgery for colon cancer: short-term outcomes of a randomised trial. Lancet Oncol 2005, 6, 477–484. [Google Scholar] [CrossRef] [PubMed]
  8. Clinical Outcomes of Surgical Therapy Study Group. A comparison of laparoscopically assisted and open colectomy for colon cancer. N Engl J Med 2004, 350, 2050–2059. [Google Scholar] [CrossRef]
  9. Jayne DG, Thorpe HC, Copeland J, et al. Five-year follow-up of the Medical Research Council CLASICC trial of laparoscopically assisted versus open surgery for colorectal cancer. Br J Surg 2010, 97, 1638–1645. [Google Scholar] [CrossRef] [PubMed]
  10. Bonjer HJ, Deijen CL, Abis GA, et al. A randomized trial of laparoscopic versus open surgery for rectal cancer. N Engl J Med 2015, 372, 1324–1332. [Google Scholar] [CrossRef]
  11. Kirchhoff P, Clavien PA, Hahnloser D. Complications in colorectal surgery: risk factors and preventive strategies. Patient Saf Surg 2010, 4, 5. [Google Scholar] [CrossRef] [PubMed]
  12. Tevis SE, Kennedy GD. Postoperative complications and implications on patient-centered outcomes. J Surg Res 2013, 181, 106–113. [Google Scholar] [CrossRef]
  13. McDermott FD, Heeney A, Kelly ME, et al. Systematic review of preoperative, intraoperative and postoperative risk factors for colorectal anastomotic leaks. Br J Surg 2015, 102, 462–479. [Google Scholar] [CrossRef] [PubMed]
  14. Kang CY, Halabi WJ, Chaudhry OO, et al. Risk factors for anastomotic leakage after anterior resection for rectal cancer. JAMA Surg 2013, 148, 65–71. [Google Scholar] [CrossRef]
  15. Wexner SD, Bergamaschi R, Lacy A, et al. The current status of robotic pelvic surgery: results of a multinational interdisciplinary consensus conference. Surg Endosc 2009, 23, 438–443. [Google Scholar] [CrossRef]
  16. Guillou PJ, Quirke P, Thorpe H, et al. Short-term endpoints of conventional versus laparoscopic-assisted surgery in patients with colorectal cancer (MRC CLASICC trial): multicentre, randomised controlled trial. Lancet 2005, 365, 1718–1726. [Google Scholar] [CrossRef]
  17. Jayne D, Pigazzi A, Marshall H, et al. Effect of robotic-assisted vs conventional laparoscopic surgery on risk of conversion to open laparotomy among patients undergoing resection for rectal cancer: The ROLARR randomized clinical trial. JAMA 2017, 318, 1569–1580. [Google Scholar] [CrossRef]
  18. Sheetz KH, Claflin J, Dimick JB. Trends in the adoption of robotic surgery for common surgical procedures. JAMA Netw Open 2020, 3, e1918911. [Google Scholar] [CrossRef]
  19. Pimentel-Nunes P, Dinis-Ribeiro M, Ponchon T, et al. Endoscopic submucosal dissection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline. Endoscopy 2015, 47, 829–854. [Google Scholar] [CrossRef]
  20. Fuccio L, Hassan C, Ponchon T, et al. Clinical outcomes after endoscopic submucosal dissection for colorectal neoplasia: a systematic review and meta-analysis. Gastrointest Endosc 2017, 86, 74–86. [Google Scholar] [CrossRef] [PubMed]
  21. Tanaka S, Kashida H, Saito Y, et al. JGES guidelines for colorectal endoscopic submucosal dissection/endoscopic mucosal resection. Dig Endosc 2020, 32, 219–239. [Google Scholar] [CrossRef]
  22. Repici A, Hassan C, De Paula Pessoa D, et al. Efficacy and safety of endoscopic submucosal dissection for colorectal neoplasia: a systematic review. Endoscopy 2012, 44, 137–150. [Google Scholar] [CrossRef]
  23. Arezzo A, Passera R, Marchese N, et al. Systematic review and meta-analysis of endoscopic submucosal dissection vs endoscopic mucosal resection for colorectal lesions. United Eur Gastroenterol J 2016, 4, 18–29. [Google Scholar] [CrossRef] [PubMed]
  24. Kalloo AN, Singh VK, Jagannath SB, et al. Flexible transgastric peritoneoscopy: a novel approach to diagnostic and therapeutic interventions in the peritoneal cavity. Gastrointest Endosc 2004, 60, 114–117. [Google Scholar] [CrossRef]
  25. McGee MF, Rosen MJ, Marks J, et al. A primer on natural orifice transluminal endoscopic surgery: building a new paradigm. Surg Innov 2006, 13, 86–93. [Google Scholar] [CrossRef]
  26. Rattner D, Kalloo A. ASGE/SAGES Working Group on Natural Orifice Transluminal Endoscopic Surgery. Surg Endosc 2006, 20, 329–333. [Google Scholar] [CrossRef]
  27. Atallah S, Albert M, Larach S. Transanal minimally invasive surgery: a giant leap forward. Surg Endosc 2010, 24, 2200–2205. [Google Scholar] [CrossRef]
  28. Hawkes EW, Blumenschein LH, Greer JD, Okamura AM. A soft robot that navigates its environment through growth. Sci Robot 2017, 2, eaan3028. [Google Scholar] [CrossRef] [PubMed]
  29. Luong J, Hawkes EW, Blumenschein LH, Okamura AM, Pham HQ. Scale considerations for everting vine robots. In: 2019 International Conference on Robotics and Automation (ICRA). IEEE; 2019:3210-3216. [CrossRef]
  30. Blumenschein LH, Gan LT, Fan JA, Okamura AM, Hawkes EW. A tip-extending soft robot enables reconfigurable and deployable antennas. IEEE Robot Autom Lett 2018, 3, 949–956. [Google Scholar] [CrossRef]
  31. Naclerio ND, Karsai A, Murray-Cooper M, et al. Controlling subterranean forces enables a fast, steerable, burrowing soft robot. Sci Robot 2021, 6, eabe2922. [Google Scholar] [CrossRef]
  32. Rus D, Tolley MT. Design, fabrication and control of soft robots. Nature 2015, 521, 467–475. [Google Scholar] [CrossRef]
  33. Cianchetti M, Laschi C, Menciassi A, Dario P. Biomedical applications of soft robotics. Nat Rev Mater 2018, 3, 143–153. [Google Scholar] [CrossRef]
  34. Brown E, Rodenberg N, Amend J, et al. Universal robotic gripper based on the jamming of granular material. Proc Natl Acad Sci USA 2010, 107, 18809–18814. [Google Scholar] [CrossRef]
  35. Cheng NG, Lobovsky MB, Keating SJ, et al. Design and analysis of a robust, low-cost, highly articulated manipulator enabled by jamming of granular media. In: 2012 IEEE International Conference on Robotics and Automation. IEEE; 2012:4328-4333. [CrossRef]
  36. Amend JR, Brown E, Rodenberg N, et al. A positive pressure universal gripper based on the jamming of granular material. IEEE Trans Robot 2012, 28, 341–350. [Google Scholar] [CrossRef]
  37. Narang YS, Vlassak JJ, Howe RD. Mechanically versatile soft machines through laminar jamming. Adv Funct Mater 2018, 28, 1707136. [Google Scholar] [CrossRef]
  38. Mohd Jani J, Leary M, Subic A, Gibson MA. A review of shape memory alloy research, applications and opportunities. Mater Des 2014, 56, 1078–1113. [Google Scholar] [CrossRef]
  39. Morgan, NB. Medical shape memory alloy applications—the market and its products. Mater Sci Eng A 2004, 378, 16–23. [Google Scholar] [CrossRef]
  40. Duerig T, Pelton A, Stöckel D. An overview of nitinol medical applications. Mater Sci Eng A 1999, 273–275, 149–160. [Google Scholar] [CrossRef]
  41. Rodrigue H, Wang W, Han MW, et al. An overview of shape memory alloy-coupled actuators and robots. Soft Robot 2017, 4, 3–15. [Google Scholar] [CrossRef]
  42. MacRae HM, McLeod RS. Handsewn vs. stapled anastomoses in colon and rectal surgery: a meta-analysis. Dis Colon Rectum 1998, 41, 180–189. [Google Scholar] [CrossRef]
  43. Neutzling CB, Lustosa SA, Proenca IM, et al. Stapled versus handsewn methods for colorectal anastomosis surgery. Cochrane Database Syst Rev 2012, 2, CD003144. [Google Scholar] [CrossRef]
  44. Choy PY, Bissett IP, Docherty JG, et al. Stapled versus handsewn methods for ileocolic anastomoses. Cochrane Database Syst Rev 2011, CD004320. [Google Scholar] [CrossRef]
  45. Lustosa SA, Matos D, Atallah AN, Castro AA. Stapled versus handsewn methods for colorectal anastomosis surgery: a systematic review of randomized controlled trials. Sao Paulo Med J 2002, 120, 132–136. [Google Scholar] [CrossRef]
  46. Sutton PA, Awad S, Perkins AC, Lobo DN. Comparison of lateral thermal spread using monopolar and bipolar diathermy, the Harmonic Scalpel and the Ligasure. Br J Surg 2010, 97, 428–433. [Google Scholar] [CrossRef] [PubMed]
  47. Hambley R, Hebda PA, Abell E, et al. Wound healing of skin incisions produced by ultrasonically vibrating knife, scalpel, electrosurgery, and carbon dioxide laser. J Dermatol Surg Oncol 1988, 14, 1213–1217. [Google Scholar] [CrossRef]
  48. Verdaasdonk RM, Borst C. Ray tracing of optically modified fiber tips 1: spherical probes. Appl Opt 1991, 30, 2159–2171. [Google Scholar] [CrossRef] [PubMed]
  49. Ritz JP, Roggan A, Isbert C, et al. Optical properties of native and coagulated porcine liver tissue between 400 and 2400 nm. Lasers Surg Med 2001, 29, 205–212. [Google Scholar] [CrossRef]
  50. Hashimoto DA, Rosman G, Rus D, Meireles OR. Artificial intelligence in surgery: promises and perils. Ann Surg 2018, 268, 70–76. [Google Scholar] [CrossRef]
  51. Maier-Hein L, Vedula SS, Speidel S, et al. Surgical data science for next-generation interventions. Nat Biomed Eng 2017, 1, 691–696. [Google Scholar] [CrossRef]
  52. Ahmidi N, Tao L, Sefati S, et al. A dataset and benchmarks for segmentation and recognition of gestures in robotic surgery. IEEE Trans Biomed Eng 2017, 64, 2025–2041. [Google Scholar] [CrossRef]
  53. Jin Y, Dou Q, Chen H, et al. SV-RCNet: workflow recognition from surgical videos using recurrent convolutional network. IEEE Trans Med Imaging 2018, 37, 1114–1126. [Google Scholar] [CrossRef]
  54. Esteva A, Kuprel B, Novoa RA, et al. Dermatologist-level classification of skin cancer with deep neural networks. Nature 2017, 542, 115–118. [Google Scholar] [CrossRef]
  55. Dowson HM, Huang A, Soon Y, et al. Systematic review of the costs of laparoscopic colorectal surgery. Dis Colon Rectum 2007, 50, 908–919. [Google Scholar] [CrossRef] [PubMed]
  56. Weeks JC, Nelson H, Gelber S, et al. Short-term quality-of-life outcomes following laparoscopic-assisted colectomy vs open colectomy for colon cancer: a randomized trial. JAMA 2002, 287, 321–328. [Google Scholar] [CrossRef]
  57. Schwenk W, Haase O, Neudecker J, Müller JM. Short term benefits for laparoscopic colorectal resection. Cochrane Database Syst Rev 2005, CD003145. [Google Scholar] [CrossRef]
  58. Kuhry E, Schwenk WF, Gaupset R, et al. Long-term results of laparoscopic colorectal cancer resection. Cochrane Database Syst Rev 2008, CD003432. [CrossRef]
  59. Ramsay CR, Grant AM, Wallace SA, et al. Assessment of the learning curve in health technologies. A systematic review. Int J Technol Assess Health Care 2000, 16, 1095–1108. [Google Scholar] [CrossRef]
  60. Barbash GI, Glied SA. New technology and health care costs—the case of robot-assisted surgery. N Engl J Med 2010, 363, 701–704. [Google Scholar] [CrossRef]
  61. Datta V, Mandalia M, Mackay S, et al. The PreOp flexible sigmoidoscopy trainer. Validation and early evaluation of a virtual reality based system. Surg Endosc 2002, 16, 1459–1463. [Google Scholar] [CrossRef]
  62. Cleary K, Peters TM. Image-guided interventions: technology review and clinical applications. Annu Rev Biomed Eng 2010, 12, 119–142. [Google Scholar] [CrossRef] [PubMed]
  63. Kramer DB, Xu S, Kesselheim AS. Regulation of medical devices in the United States and European Union. N Engl J Med 2012, 366, 848–855. [Google Scholar] [CrossRef] [PubMed]
  64. Food and Drug Administration. Guidance for industry and FDA staff: classification of products as drugs and devices and additional product classification issues. 2011. Available at: https://www.fda.gov/regulatory-information/search-fda-guidance-documents.
  65. Sedrakyan A, Campbell B, Merino JG, et al. IDEAL-D: a rational framework for evaluating and regulating the use of medical devices. BMJ 2016, 353, i2372. [Google Scholar] [CrossRef] [PubMed]
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.
Copyright: This open access article is published under a Creative Commons CC BY 4.0 license, which permit the free download, distribution, and reuse, provided that the author and preprint are cited in any reuse.
Prerpints.org logo

Preprints.org is a free preprint server supported by MDPI in Basel, Switzerland.

facebook logotwitter logolinkedin logo
bsky
MDPI Initiatives
Important Links
Subscribe

Disclaimer

Terms of Use

Privacy Policy

Privacy Settings

© 2025 MDPI (Basel, Switzerland) unless otherwise stated