[Robotic-assisted laparoscopic Heller-Dor's cardiomyotomy and fundoplication for achalasia]. / Achalasia miatt végzett robotasszisztált laparoszkópos cardiomyotomia és fundoplicatio (Heller­Dor-mutét).

INTRODUCTION: The outcomes of surgical interventions for achalasia treatment improved with the advent of minimally invasive surgery. Robotic-assisted Heller-Dor's (RAHD) procedure established over the last years, provides important advantages to surgeons, such as binocular three-dimensional vision and improvement of fine motor control. METHOD: Between October and December of 2022, first in Hungary, 3 patients (37-year-old man, 55- and 72-year-old women) underwent RAHD procedure for achalasia at the Clinical Centre of the University of Pécs using the da Vinci Xi system. RESULTS: RAHD procedure was feasible without any particular problems and the postoperative course of all three patients was uneventful. The operation times were 198, 204 and 238 minutes, including 23, 19 and 14 minutes for the setup time of the robot. By the last patient, due to an accompanying hiatal hernia, an additional hiatal reconstruction was also performed. In the first 2 cases, the patients were discharged on the 4th postoperative day, while in the last case, with the additional hiatal reconstruction, the patient was emitted on the 6th postoperative day. DISCUSSION: There are several published studies about RAHD cardiomyotomy. The general conclusion is that, in experienced hands, RAHD procedure is easy to perform, ensures a meticulous esophageal and gastric myotomy, allowing to visualize and divide each muscle fiber with a significantly lower rate of mucosal perforations. However, by RAHD procedure, the overall costs are higher, including a longer operation time during the learning curve. At the same time, the avoidance of mucosal lacerations and their possible consequences has to be weighed against the higher overall costs. CONCLUSION: Laparoscopic cardiomyotomy is the first standard upper-gastrointestinal operation where a clear advantage of the use of a surgical robot has been proven. Thus, wherever this equipment is available, it should be preferred for this procedure. Orv Hetil. 2023; 164(14): 542-547.

Endoluminal Suture-technique for the Stomach Closure of an Experimental Model.

BACKGROUND/AIM: In the modern minimally invasive era, diagnostic and therapeutic endoscopic interventions are one of the most emerging fields. For the new operational techniques, it is a major aim to develop reliable instruments, such as suturing devices for flexible endoscopes. The aim of this study was to assess the feasibility of a safe and reproducible suturing technique with an endoluminal suturing device. MATERIALS AND METHODS: The evaluation of the technique was performed in twenty explanted special prepared porcine stomachs. Three different techniques were compared, single stitches, figure-of-eight, or Z-pattern and running sutures in terms of suturing time and bursting pressure. After verification of the reliability of the method, a 3 cm long full thickness incision on the stomach was closed with the endoscopic suturing device in four surviving animals. RESULTS: In our ex vivo studies, we have shown that the figure of 8 or Z- technique is the most optimal for stomach closure without considerable time-cost, thus this technique was chosen as the standard method for the in vivo study. The endoscopic stomach wall suturing was successful in all four cases, the postoperative period was uneventful and ended on the tenth postoperative day with autopsy. CONCLUSION: With the applied suturing device, the endoscopic suturing of the stomach is safe and reproducible, thus a human application may also be justified.

The GAMMA concept (gastrointestinal activity manipulation to modulate appetite) preliminary proofs of the concept of local vibrational gastric mechanical stimulation.

BACKGROUND: Mechanical stimulation of the stretch receptors of the gastric wall can simulate the presence of indigested food leading to reduced food intake. We report the preliminary experimental results of an innovative concept of localized mechanical gastric stimulation. METHODS: In a first survival study, a biocompatible bulking agent was injected either in the greater curvature (n = 8) or in the cardia wall (n = 8) of Wistar rats. Six animals served as sham. Changes of bulking volume, leptin levels and weight gain were monitored for 3 months. In a second acute study, a micro-motor (n = 10; MM) or a size-paired inactive device (n = 10; ID) where applied on the cardia, while 10 additional rats served as sham. Serum ghrelin and leptin were measured at baseline and every hour (T0-T1-T2-T3), during 3 h. In a third study, 24 implants of various shapes and sizes were introduced into the gastric subserosa of 6 Yucatan pigs. Monthly CT scans and gastroscopies were done for 6 months. RESULTS: Weight gain in the CW group was significant lower after 2 weeks and 3 months when compared to the shame and GC (p = 0.01/p = 0.01 and p = 0.048/p = 0.038 respectively). Significant lower increase of leptin production occurred at 2 weeks (p = 0.01) and 3 months (p = 0.008) in CW vs. SG. In the MM group significant reduction of the serum ghrelin was seen after 3 h. Leptin was significantly increased in both MM and ID groups after 3 h, while it was significantly reduced in sham rats. The global device retention was 43.5%. Devices with lower profile and with a biocompatible coating remained more likely in place without complications. CONCLUSIONS: Gastric mechanical stimulation induced a reduced weight gain and hormonal changes. Low profile and coated devices inserted within the gastric wall are more likely to be integrated.

Experimental Evaluation of the Optimal Suture Pattern With a Flexible Endoscopic Suturing System.

BACKGROUND: The ability to perform reliable, secure endoluminal closure of the gastrointestinal tract wall, is a prerequisite to support the progress of the emerging field of endoluminal surgery. Along with advanced clipping systems, flexible endoscopic suturing devices are commercially available. Current systems can replicate traditional surgical suturing patterns in the endoluminal environment. The aim of this study was to evaluate the optimal endoluminal suturing technique using a flexible endoscopic suturing device. MATERIALS AND METHODS: Procedures were performed on bench-top simulators containing 20 explanted porcine stomachs. A standardized 3-cm full-thickness incision was created on the anterior wall of each stomach using monopolar cautery. The gastrotomy was closed endoscopically using an over-the-scope suturing device (OverStitch, Apollo Endosurgery; Austin, TX). Three different techniques were used: single stitches, figure-of-8 pattern, and running suture. Material consumption and operation time were recorded and bursting pressure measurement of the closure was performed. RESULTS: No statistically significant differences were identified in suturing time. Suturing time (minutes) was slightly shorter with the figure-of-8 technique (41.14 ± 4.6) versus interrupted (45.75 ± 1.1) versus continuous (51.44 ± 10.0), but the difference was not statistically significant. The number of sutures required was greater in the interrupted group. No significant difference was found in the burst pressure (mm Hg): figure-of-8 (45.85 ± 26.2) versus interrupted (30.5 ± 22.89) versus continuous (32.0 ± 26.5). In the figure-of-8 group, 85.5% of cases were leakproof above 30 mm Hg, while in the other groups only 50% of cases were so. CONCLUSION: A figure-of-8 suturing pattern seems to be the preferable suturing technique with the endoscopic suturing device.

Endoluminal surgical triangulation 2.0: A new flexible surgical robot. Preliminary pre-clinical results with colonic submucosal dissection.

BACKGROUND: Complex intraluminal surgical interventions of the gastrointestinal tract are challenging due to the limitation of existing instruments. Our group has developed a master-slave robotic flexible endoscopic platform that provides instrument triangulation in an endoluminal environment. MATERIALS AND METHODS: Colonic endoscopic submucosal dissections (ESD) were carried out in eight pigs. The robot was introduced transanally. A combination of adapted tele-operated instruments was used. Specimens were inspected and measured. RESULTS: Out of 18 ESDs in total, 12 were successfully completed. Among the completed procedures, two perforations and one system failure occurred and were managed intraoperatively. There was no major bleeding. Mean size of the removed specimens was 18.2 ± 9.8 cm2 and mean total procedure time was 73 ± 35.5 min. CONCLUSIONS: Experimental colorectal ESDs using the flexible surgical robot were feasible and reflected a short learning curve. After some technical improvements the system might allow for a wider adoption of complex endoluminal surgical procedures.

A Newly Designed Enterocutaneous Esophageal Fistula Model in the Pig.

Background Fistulas after esophagectomy are a significant cause of morbidity and mortality. Several endoscopic treatments have been attempted, with varying success. An experimental model that could validate new approaches such as cellular therapies is highly desirable. The aim of this study was to create a chronic esophageal enterocutaneous fistula model in order to study future experimental treatment options. Methods Eight pigs (six 35-kg young German and two 50-kg adult Yucatan pigs) were used. Through a left and right cervicotomy, under endoscopic view, 1 (group A, n = 6) or 2 (group B, n = 7) plastic catheters were introduced into the esophagus 30 cm from the dental arches bilaterally and left in place for 1 month. Radiologic and endoscopic fistula tract evaluations were performed at postoperative day (POD; 30) and at sacrifice (POD 45). Results Three fistulas were excluded from the study because of early (POD 5) dislodgment of the catheter, with complete fistula closure. At catheter removal (POD 30), the external orifice was larger in group B (5.2 ± 1.1 mm vs 2.6 ± 0.4 mm) with more severe inflammation (72% vs 33%). At POD 45, the external orifice was closed in all fistulas in group A and in 1/7 in group B. At necropsy, the fistula tract was still present in all animals. Yucatan pigs showed more complex tracts, with a high level of necrosis and substantial fibrotic infiltration. Conclusions In this article, we show a reproducible, safe, and effective technique to create an esophagocutaneous fistula model in a large experimental animal.

Confocal Imaging and Tissue-Specific Fluorescent Probes for Real-Time In Vivo Immunohistochemistry. Proof of the Concept in a Gastric Lymph Node Metastasis Model.

BACKGROUND: Tumor-specific fluorescent antibodies, which can be recognized at a cellular or tissue level using optical imaging such as confocal laser endomicroscopy (CLE), could provide a means for rapid and accurate tumor diagnosis and staging. The aim of this study was to evaluate the ability of CLE to detect the presence of tagged cells within lymph nodes in an original simulated metastatic model. MATERIALS AND METHODS: A solution of indocyanine green containing a suspension of porcine hepatocytes, marked with carboxy-fluorescein-succinimidyl-ester (CFSE), was injected endoscopically in the gastric submucosa of 10 pigs. Fluorescence lymphography using a near-infrared laparoscope was used to identify sentinel and secondary drainage nodes. Additionally, a nonfluorescent gastric and a mesenteric node were identified. Every 5-10 min, those nodes were scanned using probe-based or needle-based CLE (pCLE or nCLE). Immunohistochemistry (IHC) using anti-cytokeratin 18 antibodies was subsequently performed to confirm the presence of hepatocytes in the lymph nodes. RESULTS: A total of 36 lymph nodes were analyzed with both CLE probes. Hepatocyte penetration in lymph nodes, as assessed by repeated CLE scanning, took 10-40 min after submucosal injection. Concordance between CLE and IHC was 84 and 72 % for pCLE and nCLE, respectively. False negatives were partly due to incomplete CFSE labeling of hepatocytes, which could not be recognized by CLE, but were detected with IHC. CONCLUSIONS: Real-time CLE analysis effectively recognized the presence in perigastric nodes of marked hepatic cells that had been injected endoscopically in the stomach. Validation studies on tumor-bearing animals using tumor-specific antibodies should be performed.

Novel laparoscopic narrow band imaging for real-time detection of bile leak during hepatectomy: proof of the concept in a porcine model.

INTRODUCTION: Bile leakage is a serious complication occurring in up to 10 % of hepatic resections. Intraoperative detection of bile leakage is challenging, and concomitant blood oozing can mask the presence of bile. Intraductal dye injection [methylene blue or indocyanine green (ICG)] is a validated technique to detect bile leakage. However, this method is time-consuming, particularly in the laparoscopic setting. A novel narrow band imaging (NBI) modality (SPECTRA-A; Karl Storz, Tuttlingen, Germany) allows easy discrimination of the presence of bile, which appears in clear orange, by image processing. The aim of this experimental study was to evaluate SPECTRA-A ability to detect bile leakage. METHODS: Twelve laparoscopic partial hepatectomies were performed in seven pigs. The common bile duct was clipped distally and dissected, and a catheter was inserted and secured with a suture or a clip. Liver dissection was achieved with an ultrasonic cutting device. Dissection surfaces were checked by frequently switching on the SPECTRA filter to identify the presence of bile leakage. Intraductal ICG injection through the catheter was performed to confirm SPECTRA findings. RESULTS: Three active bile leakages were obtained out of 12 hepatectomies and successfully detected intraoperatively by the SPECTRA. There was complete concordance between NBI and ICG fluorescence detection. No active leaks were found in the remaining cases with both techniques. The leaking area identified was sutured, and SPECTRA was used to assess the success of the repair. CONCLUSIONS: The SPECTRA laparoscopic image processing system allows for rapid detection of bile leaks following hepatectomy without any contrast injection.

Improving Echo-Guided Procedures Using an Ultrasound-CT Image Fusion System.

INTRODUCTION: Image fusion between ultrasound (US) and computed tomography (CT) scan or magnetic resonance can increase operator accuracy in targeting liver lesions, particularly when those are undetectable with US alone. We have developed a modular gel to simulate hepatic solid lesions for educational purposes in imaging and minimally invasive ablation techniques. We aimed to assess the impact of image fusion in targeting artificial hepatic lesions during the hands-on part of 2 courses (basic and advanced) in hepatobiliary surgery. MATERIALS AND METHODS: Under US guidance, 10 fake tumors of various sizes were created in the livers of 2 pigs, by percutaneous injection of a biocompatible gel engineered to be hyperdense on CT scanning and barely detectable on US. A CT scan was obtained and a CT-US image fusion was performed using the ACUSON S3000 US system (Siemens Healthcare, Germany). A total of 12 blinded course attendants, were asked in turn to perform a 10-minute liver scan with US alone followed by a 10-minute scan using image fusion. RESULTS: Using US alone, the expert managed to identify all lesions successfully. The true positive rate for course attendants with US alone was 14/36 and 2/24 in the advanced and basic courses, respectively. The total number of false positives identified was 26. With image fusion, the rate of true positives significantly increased to 31/36 (P < .001) in the advanced group and 16/24 in the basic group (P < .001). The total number of false positives, considering all participants, decreased to 4 (P < .001). CONCLUSIONS: Image fusion significantly increases accuracy in targeting hepatic lesions and might improve echo-guided procedures.

Esophageal covered stent fixation using an endoscopic over-the-scope clip. Mechanical proof of the concept and first clinical experience.

BACKGROUND AND STUDY AIMS: Endoscopic suturing reduces stent migration, but is challenging and time-consuming. We compare endoscopic suturing versus anchoring with a novel over-the-scope clip (Padlock) to fix esophageal stents. Additionally, the first clinical case of Padlock stent fixation is reported. MATERIALS AND METHODS: A fully covered esophageal stent was placed in 11 pigs and fixed with one figure-of-eight suture (n = 5) or with a Padlock (n = 4) or not fixed (controls; n = 2). The force required to mobilize the stent was recorded. CLINICAL CASE: an esophageal stent was fixed with a Padlock and endoscopically removed 1 month later, in an 82-year-old patient. RESULTS: Mean force (newton) to mobilize the stent was similar after suturing and Padlock fixation (23.99 ± 14.91 vs. 19.97 ± 7.62; p = 0.32). In controls was 7 and 11 Newtons. Suturing time (seconds) was longer than Padlock application (455.4 ± 144.83 vs. 155 ± 12.9; p = 0.002). CLINICAL CASE: stent fixation was feasible and uncomplicated. Removal was easy, and only mild bleeding occurred. CONCLUSIONS: Padlock is faster than endoscopic suturing and achieves similar stent fixation. The first clinical case confirms the feasibility of the method.

Endoluminal full-thickness suture repair of gastrotomy: a survival study.

BACKGROUND: Treatment of perforations and complications related to gastrointestinal (GI) surgery and interventional flexible endoscopy is increasingly performed endoscopically. New devices enabling secure full-thickness GI tract closures through flexible endoscopic platforms have been recently developed. AIM: To assess feasibility of endoscopic closure of a large gastrotomy using a tip-mounted flexible endoscopic suturing device. METHODS: Six pigs were involved in this study. Standardized 3-cm full-thickness gastrotomies were created endoscopically in various areas of the gastric wall, in all animals, using monopolar cautery. A peritoneoscopy was performed through the gastrotomy. In four pigs, gastrotomy was repaired with an endoscopic suturing device (OverStitch™, Apollo Medical). Full-thickness suturing was started at the edges of the incision, and a figure-of-eight pattern was used. A dedicated helical tissue grasper combined with endoscopic suction was used to retract incision borders and ensure full-thickness closure. Sutures were locked using a cinching device. In two pigs, the gastrotomy was closed laparoscopically and served as a control. An air leak test was performed. On postoperative day 10 (POD 10), all pigs underwent endoscopy and laparotomy and were euthanized. RESULTS: Mean endoscopic suturing time was 57.5 ± 14.15 min, and four to six sutures were delivered per incision. Laparoscopic suturing time was 8 min. All leak tests were negative. No intraoperative or postoperative complications occurred. On POD 10, all gastrotomies were healed. In one animal, thick adhesions were found surrounding the suture site but no leak was identified. CONCLUSIONS: Full-thickness suturing of experimental gastrotomies using the OverStitch™ device is feasible and effective.

Gastric supply manipulation to modulate ghrelin production and enhance vascularization to the cardia: proof of the concept in a porcine model.

INTRODUCTION: Selective embolization of the left-gastric artery (LGA) reduces levels of ghrelin and achieves significant short-term weight loss. However, embolization of the LGA would prevent the performance of bariatric procedures because the high-risk leakage area (gastroesophageal junction [GEJ]) would be devascularized. AIM: To assess an alternative vascular approach to the modulation of ghrelin levels and generate a blood flow manipulation, consequently increasing the vascular supply to the GEJ. MATERIALS AND METHODS: A total of 6 pigs underwent a laparoscopic clipping of the left gastroepiploic artery. Preoperative and postoperative CT angiographies were performed. Ghrelin levels were assessed perioperatively and then once per week for 3 weeks. Reactive oxygen species (ROS; expressed as ROS/mg of dry weight [DW]), mitochondria respiratory rate, and capillary lactates were assessed before and 1 hour after clipping (T0 and T1) and after 3 weeks of survival (T2), on seromuscular biopsies. A celiac trunk angiography was performed at 3 weeks. RESULTS: Mean (±standard deviation) ghrelin levels were significantly reduced 1 hour after clipping (1902 ± 307.8 pg/mL vs. 1084 ± 680.0; P = .04) and at 3 weeks (954.5 ± 473.2 pg/mL; P = .01). Mean ROS levels were statistically significantly decreased at the cardia at T2 when compared with T0 (0.018 ± 0.006 mg/DW vs. 0.02957 ± 0.0096 mg/DW; P = .01) and T1 (0.0376 ± 0.008 mg/DW; P = .007). Capillary lactates were significantly decreased after 3 weeks, and the mitochondria respiratory rate remained constant over time at the cardia and pylorus, showing significant regional differences. CONCLUSIONS: Manipulation of the gastric flow targeting the gastroepiploic arcade induces ghrelin reduction. An endovascular approach is currently under evaluation.

Flexible endoscopic single-incision extraperitoneal implant and fixation of peritoneal dialysis catheter: proof of concept in the porcine model.

BACKGROUND: Peritoneal dialysis (PD) catheters placed in the pelvic space without anchoring present a high rate of migration. We aimed to assess the feasibility of a single-incision approach, using a flexible endoscopic preperitoneal tunneling for catheter implantation and fixation. MATERIALS AND METHODS: Eight pigs were involved in this experimental study. A 2/0 Vicryl loop was sutured at the tip of a PD catheter. In 4 pigs, a 1.5 cm incision was made on the left paramedian line and the parietal peritoneal layer was identified by splitting rectal muscles. A gastroscope was inserted in the incision and advanced in the extraperitoneal space. An exit hole was made in the peritoneum over the low pelvic cavity. A guidewire was left in the abdominal cavity, and the PD catheter was inserted over the guidewire. The endoscope was inserted in the tunnel again, and endoscopic clips were deployed over the Vicryl loop to fix the catheter. In 4 pigs, the PD catheter was inserted laparoscopically using a two-port approach. The catheter's tip was fixed with laparoscopic clips on the Vicryl loop. A strain test to assess the force required to detach clips was performed using a digital dynamometer. RESULTS: Operative time for flexible endoscopic tunneling was longer when compared to the laparoscopic implant (29.5 ± 4.43 vs. 22.7 ± 2.51 min). Mean force to displace the catheter was similar after flexible endoscopic fixation when compared to laparoscopic clip fixation (5.57 N ± 2.76 vs. 4.15 N ± 1.76). CONCLUSIONS: Flexible endoscopic extraperitoneal tunneling allows for minimally invasive single-incision PD catheter placement and fixation.

Embolization of arterial gastric supply in obesity (EMBARGO): an endovascular approach in the management of morbid obesity. proof of the concept in the porcine model.

BACKGROUND: Embolization of the left gastric artery (LGA) reduces circulating levels of ghrelin, but might prevent from further obesity surgery, particularly sleeve gastrectomy (SG), since the gastroesophageal junction (GEJ), depending on LGA, would be devascularized. Our aim was to evaluate, in an experimental animal study, an endovascular approach targeting arteries of the gastroepiploic arcade aiming to modulate ghrelin levels and to generate an increased vascular supply of the GEJ to reduce the risks of staple-line leaks after SG. METHODS: Seven pigs underwent embolization of both left and right gastroepiploic arteries (LGEA and RGEA) using 500-700-µ microspheres (embolization of arterial gastric supply in obesity (EMBARGO)-alpha). A SG was performed in six pigs 3 weeks after EMBARGO-alpha and on eight controls. Capillary lactates were measured at the cardia and pylorus. Five pigs underwent coiling of RGEA and embolization of LGEA using both coils and 100-300-µ microspheres (EMBARGO-beta). Ghrelin levels were assessed before and once per week after both EMBARGOs. Control celiac trunk angiography was performed at 3 weeks (alpha) and 4 weeks (beta). RESULTS: No significant ghrelin reduction was obtained with EMBARGO-alpha at 3 weeks when compared to baseline. Significant ghrelin reduction was found 3 weeks (p = 0.0363) and 4 weeks (p = 0.025) after EMBARGO-beta. Post-EMBARGO-alpha animals presented a significantly lower increase in cardia lactates when compared to controls after SG. Control angiography showed a significantly increased fundic vascular network in 5/6 animals after EMBARGO-alpha and in 5/5 after EMBARGO-beta. CONCLUSIONS: EMBARGO is effective to decrease ghrelin production and can enhance the vascular supply of the GEJ, preparing the vascular background for a SG.

[Laparoscopic reconstruction in traumatic rupture of the diaphragm]. / Traumás rekeszruptura laparoscopos reconstructiója.

The authors report the case of a 63-year-old patient who was polytraumatized in a motor vehicle accident and suffered multiple traumatic injuries. Chest and pelvic fractures as well as left-sided diaphragmatic rupture with associated omentum herniation were diagnosed on CT scan. None of the injuries required urgent surgical intervention. After 10 days supportive therapy, elective laparoscopic reconstruction of the diaphragmatic hernia was performed. The authors discuss the role of laparoscopic diaphragm reconstruction.

Real-time navigation by fluorescence-based enhanced reality for precise estimation of future anastomotic site in digestive surgery.

BACKGROUND: Fluorescence-based enhanced reality (FLER) is a technique to evaluate intestinal perfusion based on the elaboration of the Indocyanine Green fluorescence signal. The aim of the study was to assess FLER's performances in evaluating perfusion in an animal model of long-lasting intestinal ischemia. MATERIALS AND METHODS: An ischemic segment was created in 18 small bowel loops in 6 pigs. After 2 h (n = 6), 4 h (n = 6), and 6 h (n = 6), loops were evaluated clinically and by FLER to delineate five regions of interest (ROIs): ischemic zone (ROI 1), presumed viable margins (ROI 2a-2b), and vascularized areas (3a-3b). Capillary lactates were measured to compare clinical vs. FLER assessment. Basal (V 0 ) and maximal (V max) mitochondrial respiration rates were determined according to FLER. RESULTS: Lactates (mmol/L) at clinically identified resection lines were significantly higher when compared to those identified by FLER (2.43 ± 0.95 vs. 1.55 ± 0.33 p = 0.02) after 4 h of ischemia. Lactates at 2 h at ROI 1 were 5.45 ± 2.44 vs. 1.9 ± 0.6 (2a-2b; p < 0.0001) vs. 1.2 ± 0.3 (3a-3b; p < 0.0001). At 4 h, lactates were 4.36 ± 1.32 (ROI 1) vs. 1.83 ± 0.81 (2a-2b; p < 0.0001) vs. 1.35 ± 0.67 (3a-3b; p < 0.0001). At 6 h, lactates were 4.16 ± 2.55 vs. 1.8 ± 1.2 vs. 1.45 ± 0.83 at ROI 1 vs. 2a--2b (p = 0.013) vs. 3a-3b (p = 0.0035). Mean V 0 and V max (pmolO2/second/mg of tissue) were significantly impaired after 4 and 6 h at ROI 1 (V 0 (4h) = 34.83 ± 10.39; V max (4h) = 76.6 ± 29.09; V 0 (6h) = 44.1 ± 12.37 and V max (6h) = 116.1 ± 40.1) when compared to 2a--2b (V 0 (4h) = 67.1 ± 17.47 p = 0.00039; V max (4h) = 146.8 ± 55.47 p = 0.0054; V 0 (6h) = 63.9 ± 28.99 p = 0.03; V max (6h) = 167.2 ± 56.96 p = 0.01). V 0 and V max were significantly higher at 3a-3b. CONCLUSIONS: FLER may identify the future anastomotic site even after repetitive assessments and long-standing bowel ischemia.

Probe-based confocal laser endomicroscopy and fluorescence-based enhanced reality for real-time assessment of intestinal microcirculation in a porcine model of sigmoid ischemia.

BACKGROUND AND AIM: Surgeons currently rely on visual clues to estimate the presence of sufficient vascularity for safe anastomosis. We aimed to assess the accuracy of endoluminal confocal laser endomicroscopy (CLE) and laparoscopic fluorescence-based enhanced reality (FLER), using near-infrared imaging and fluorescence from injected Indocyanine Green, to identify the transition from ischemic to vascular areas in a porcine model of mesenteric ischemia. METHODS: Six pigs underwent 1-h sigmoid segmental ischemia. The ischemic area was evaluated by clinical assessment and FLER to determine presumed viable margins. For each sigmoid colon, 5 regions of interest (ROIs) were identified: ischemic (ROI 1), presumed viable margins ROI 2a (distal) and 2b (proximal), and vascular areas 3a (distal) and 3b (proximal). After injection of fluorescein, CLE scanning of the mucosa from the ischemic area toward viable margins was performed. Capillary blood samples were obtained by puncturing the serosa at the ROIs, and capillary lactates were measured with the EDGE(®) analyzer. RESULTS: Capillary lactates were significantly higher at ROI 1 (4.91 mmol/L) when compared to resection margins (2.8 mmol/L; mean difference: 2.11; p < 0.05) identified by FLER. There was no significant difference in lactates between ROI1 and resection margins identified by clinical evaluation. In 50 % of cases, ROI 2aCLINIC-2bCLINIC were considered to match (<1 cm distance) with ROI 2aFLER-2bFLER. Confocal analysis revealed specific clues to identify the transition from ischemic to viable areas corresponding to those assessed by FLER in 11/12 cases versus 7/12 for those identified by clinical evaluation. CONCLUSIONS: In this experimental model, FLER and CLE were more accurate than clinical evaluation to delineate bowel vascularization.

Mucosal excision and suturing for obesity and GERD.

BACKGROUND: Suture and staple-based endoluminal devices for gastroesophageal reflux disease (GERD) and obesity have failed to demonstrate long-term efficacy. OBJECTIVE: To demonstrate the feasibility of mucosal excision and full-thickness suture apposition of the excision beds to create sufficient scar tissue formation at the gastroesophageal junction for the intraluminal treatment of GERD or obesity. DESIGN: Survival animal experiments. PATIENTS: Seven mongrel dogs. Interventions. Under general endotracheal anesthesia, a Barostat test was performed on 4 dogs. A mucosal excision device was introduced through the esophagus into the proximal stomach. Two to 4 mucosal excisions were performed on all dogs at or just below the gastroesophageal junction and the mucosal pieces were removed. After hemostasis, an intraluminal suturing instrument was introduced and either 2 or 4 sutures were placed through the excision beds to bring them into apposition. These were tied and the suture strands cut. All dogs were survived for 2 months. End-term endoscopies were performed, and a repeat Barostat procedure was performed on the animals undergoing an antireflux procedure. After euthanasia the stomachs were explanted, examined, photographed, and sectioned for histologic examination. RESULTS: All dogs survived without complication. In the 4 GERD dogs, the Barostat studies demonstrated a significant decrease in gastroesophageal junction compliance. In the 3 dogs undergoing the obesity procedure, the gastric outlet apposition to a 6-mm endoscope was satisfactory with full insufflation and the desired scarring was seen on histologic examination. CONCLUSION: It is possible to create adequate gastroesophageal junction scarring for the treatment of GERD and obesity. A clinical pilot study will be initiated.