Skill progress during a dedicated societal robotic surgery training curriculum including several robotic surgery platforms.

BACKGROUND: Robot-assisted procedures are increasingly common, and several systems are available for thoraco-abdominal surgery. Specific structured training is necessary, while access to these systems is still limited. This study aimed to assess surgeons' skill progress during consecutive training days of a curriculum with exposure to different robotic systems. METHODS: This prospective observational study enrolled 47 surgeons with anonymized analysis of SimNow™ simulator performance scores and dedicated questionnaires after written consent. The primary outcome was the overall score, based on economy of motion, time to complete the exercise, and penalty for errors. Course participants in 2022-2023 had chosen 2 full hands-on days on Da Vinci® consoles with either virtual reality (VR) simulation training using the SimNow (n = 21, 44.7%) or digestive surgery procedures with a live animal model (n = 26, 55.3%). In all participants, training on Da Vinci® systems included console functions and principles of docking, camera, and instrument use for console and procedural training. They additionally had access to introductory dry-lab and VR simulator exercises on the Versius, HugoTMRAS, and Dexter systems and to VR exercises on the ROBOTiS simulator. RESULTS: The participants (16F/31M, median age 40 years, range 29-58) from various surgical specialties (general/visceral/vascular) had no (n = 35, 74.5%) or little (n = 12, 25.5%) robotic experience including bedside assistance only and 20 (42.6%) had robotic simulator experience. The demographic variables fully completed by 44/47 participants (93.6%) and choice of module had no significant impact on the primary outcome. The considerable performance improvement from days 1 to 2 was exemplified by a significantly increased economy of motion and decreased amount of excessive force. CONCLUSION: Robotic surgical training is increasingly complex with several systems on the market. Within a dedicated robotic surgery curriculum and based on integrated performance metrics, a significant improvement of skill levels was observed in a relatively short period of time.

Obesity paradox: is a high body mass index positively influencing survival outcomes in gynecological cancers? A systematic review and meta-analysis.

OBJECTIVE: Obesity represents an exponentially growing preventable disease leading to different health complications, particularly when associated with cancer. In recent years, however, an 'obesity paradox' has been hypothesized where obese individuals affected by cancer counterintuitively show better survival rates. The aim of this systematic review and meta-analysis is to assess whether the prognosis in gynecological malignancies is positively influenced by obesity. METHODS: This study adheres to PRISMA guidelines and is registered with PROSPERO. Studies reporting the impact of a body mass index (BMI) of >30 kg/m2 compared with <30 kg/m2 in patients with gynecological cancers listed in PubMed, Google Scholar and ClinicalTrials.gov were included in the analysis. The Quality Assessment of Diagnostic Accuracy Studies 2 tool (QUADAS-2) was used for quality assessment of the selected articles. RESULTS: Twenty-one studies were identified for the meta-analysis, including 14 108 patients with cervical, ovarian, or endometrial cancer. There was no benefit in 5-year overall survival for obese patients compared with non-obese patients (OR 1.2, 95% CI 1.00 to 1.44, p=0.05; I2=71%). When pooling for cancer sub-groups, there were no statistically significant differences in 5-year overall survival in patients with cervical cancer and 5-year overall survival and progression-free survival in patients with ovarian cancer. For obese women diagnosed with endometrial cancer, a significant decrease of 44% in 5-year overall survival (p=0.01) was found, with no significant difference in 5-year disease-free survival (p=0.78). CONCLUSION: According to the results of the present meta-analysis, a BMI of ≥30 kg/m2 does not have a positive prognostic effect on survival compared with a BMI of <30 kg/m2 in women diagnosed with gynecological cancers. The existence of the 'obesity paradox' in other fields, however, suggests the importance of further investigations with prospective studies.

Ultrasound-guided robotic surgical procedures: a systematic review.

INTRODUCTION: Ultrasound has been nicknamed "the surgeon's stethoscope". The advantages of laparoscopic ultrasound beyond a substitute for the sense of touch are considerable, especially for robotic surgery. Being able to see through parenchyma and into vascular structures enables to avoid unnecessary dissection by providing a thorough assessment at every stage without the need for contrast media or ionising radiation. The limitations of restricted angulation and access within the abdominal cavity during laparoscopy can be overcome by robotic handling of miniaturised ultrasound probes and the use of various and specific frequencies will meet tissue- and organ-specific characteristics. The aim of this systematic review was to assess the reported applications of intraoperative ultrasound-guided robotic surgery and to outline future perspectives. METHODS: The study adhered to the PRISMA guidelines. PubMed, Google Scholar, ScienceDirect and ClinicalTrials.gov were searched up to October 2023. Manuscripts reporting data on ultrasound-guided robotic procedures were included in the qualitative analysis. RESULTS: 20 studies met the inclusion criteria. The majority (53%) were related to the field of general surgery during liver, pancreas, spleen, gallbladder/bile duct, vascular and rectal surgery. This was followed by other fields of oncological surgery (42%) including urology, lung surgery, and retroperitoneal lymphadenectomy for metastases. Among the studies, ten (53%) focused on locating tumoral lesions and defining resection margins, four (15%) were designed to test the feasibility of robotic ultrasound-guided surgery, while two (10.5%) aimed to compare robotic and laparoscopic ultrasound probes. Additionally two studies (10.5%) evaluated the robotic drop-in probe one (5%) assessed the hepatic tissue consistency and another one (5%) aimed to visualize the blood flow in the splenic artery. CONCLUSION: The advantages of robotic instrumentation, including ergonomics, dexterity, and precision of movements, are of relevance for robotic intraoperative ultrasound (RIOUS). The present systematic review demonstrates the virtue of RIOUS to support surgeons and potentially reduce minimally invasive procedure times.

Fertility-sparing uterine displacement for pelvic malignancies: surgical options and radiotherapy dosimetry on a human cadaver.

BACKGROUND: Radio(chemo)therapy is often required in pelvic malignancies (cancer of the anus, rectum, cervix). Direct irradiation adversely affects ovarian and endometrial function, compromising the fertility of women. While ovarian transposition is an established method to move the ovaries away from the radiation field, surgical procedures to displace the uterus are investigational. This study demonstrates the surgical options for uterine displacement in relation to the radiation dose received.  METHODS: The uterine displacement techniques were carried out sequentially in a human female cadaver to demonstrate each procedure step by step and assess the uterine positions with dosimetric CT scans in a hybrid operating room. Two treatment plans (anal and rectal cancer) were simulated on each of the four dosimetric scans (1. anatomical position, 2. uterine suspension of the round ligaments to the abdominal wall 3. ventrofixation of the uterine fundus at the umbilical level, 4. uterine transposition). Treatments were planned on Eclipse® System (Varian Medical Systems®,USA) using Volumetric Modulated Arc Therapy. Data about maximum (Dmax) and mean (Dmean) radiation dose received and the volume receiving 14 Gy (V14Gy) were collected. RESULTS: All procedures were completed without technical complications. In the rectal cancer simulation with delivery of 50 Gy to the tumor, Dmax, Dmean and V14Gy to the uterus were respectively 52,8 Gy, 34,3 Gy and 30,5cc (1), 31,8 Gy, 20,2 Gy and 22.0cc (2), 24,4 Gy, 6,8 Gy and 5,5cc (3), 1,8 Gy, 0,6 Gy and 0,0cc (4). For anal cancer, delivering 64 Gy to the tumor respectively 46,7 Gy, 34,8 Gy and 31,3cc (1), 34,3 Gy, 20,0 Gy and 21,5cc (2), 21,8 Gy, 5,9 Gy and 2,6cc (3), 1,4 Gy, 0,7 Gy and 0,0cc (4). CONCLUSIONS: The feasibility of several uterine displacement procedures was safely demonstrated. Increasing distance to the radiation field requires more complex surgical interventions to minimize radiation exposure. Surgical strategy needs to be tailored to the multidisciplinary treatment plan, and uterine transposition is the most technically complex with the least dose received.

The vaginal route for minimally invasive surgery: a practical guide for general surgeons.

INTRODUCTION: Vaginal approaches have become routine in the field of gynecologic surgery, whereas in general surgery vaginal wall transection is an infrequent practice typically reserved for extensive tumor resections. Approximately two decades ago, natural orifice transluminal endoscopic surgery (NOTES) revolutionized conventional boundaries by accessing the peritoneal cavity transorally, transrectally, or transvaginally, enabling general surgery without visible scars. Although transvaginal approaches have been successfully used for various abdominal procedures by general surgeons, a gap remains in comprehensive training to fully exploit the potential of this route. MATERIAL AND METHODS: PubMed, Google Scholar, and Scopus databases were searched to retrieve relevant articles illustrating how general surgeons can adeptly manage vaginal approaches. RESULTS: The article presents a practical framework for general surgeons to execute a complete vaginal approach, addressing the management of vaginal specimen extraction and vaginal cuff closure, even in the absence of an experienced gynecologist. CONCLUSION: The evolution of abdominal surgery is moving towards less invasive techniques, emphasizing the importance of understanding the nuances and challenges associated with the vaginal route. This approach is linked to minimal oncological, sexual, and infective complications, and to the absence of pregnancy-related complications. Such knowledge becomes increasingly crucial, particularly with the renewed demand for transvaginal access in robot-assisted NOTES procedures.

Robotically assisted augmented reality system for identification of targeted lymph nodes in laparoscopic gynecological surgery: a first step toward the identification of sentinel node : Augmented reality in gynecological surgery.

BACKGROUND: To prove feasibility of multimodal and temporal fusion of laparoscopic images with preoperative computed tomography scans for a real-time in vivo-targeted lymph node (TLN) detection during minimally invasive pelvic lymphadenectomy and to validate and enable such guidance for safe and accurate sentinel lymph node dissection, including anatomical landmarks in an experimental model. METHODS: A measurement campaign determined the most accurate tracking system (UR5-Cobot versus NDI Polaris). The subsequent interventions on two pigs consisted of an identification of artificial TLN and anatomical landmarks without and with augmented reality (AR) assistance. The AR overlay on target structures was quantitatively evaluated. The clinical relevance of our system was assessed via a questionnaire completed by experienced and trainee surgeons. RESULTS: An AR-based robotic assistance system that performed real-time multimodal and temporal fusion of laparoscopic images with preoperative medical images was developed and tested. It enabled the detection of TLN and their surrounding anatomical structures during pelvic lymphadenectomy. Accuracy of the CT overlay was > 90%, with overflow rates < 6%. When comparing AR to direct vision, we found that scores were significatively higher in AR for all target structures. AR aided both experienced surgeons and trainees, whether it was for TLN, ureter, or vessel identification. CONCLUSION: This computer-assisted system was reliable, safe, and accurate, and the present achievements represent a first step toward a clinical study.

Computer-assisted quantification and visualization of bowel perfusion using fluorescence-based enhanced reality in left-sided colonic resections.

BACKGROUND: Fluorescence-based enhanced reality (FLER) is a computer-based quantification method of fluorescence angiographies to evaluate bowel perfusion. The aim of this prospective trial was to assess the clinical feasibility and to correlate FLER with metabolic markers of perfusion, during colorectal resections. METHODS: FLER analysis and visualization was performed in 22 patients (diverticulitis n = 17; colorectal cancer n = 5) intra- and extra-abdominally during distal and proximal resection, respectively. The fluorescence signal of indocyanine green (0.2 mg/kg) was captured using a near-infrared camera and computed to create a virtual color-coded cartography. This was overlaid onto the bowel (enhanced reality). It helped to identify regions of interest (ROIs) where samples were subsequently obtained. Resections were performed strictly guided according to clinical decision. On the surgical specimen, samplings were made at different ROIs to measure intestinal lactates (mmol/L) and mitochondria efficiency as acceptor control ratio (ACR). RESULTS: The native (unquantified) fluorescent signal diffused to obvious ischemic areas during the distal appreciation. Proximally, a lower diffusion of ICG was observed. Five anastomotic complications occurred. The expected values of local capillary lactates were correlated with the measured values both proximally (3.62 ± 2.48 expected vs. 3.17 ± 2.8 actual; rho 0.89; p = 0.0006) and distally (4.5 ± 3 expected vs. 4 ± 2.5 actual; rho 0.73; p = 0.0021). FLER values correlated with ACR at the proximal site (rho 0.76; p = 0.04) and at the ischemic zone (rho 0.71; p = 0.01). In complicated cases, lactates at the proximal resection site were higher (5.8 ± 4.5) as opposed to uncomplicated cases (2.45 ± 1.5; p = 0.008). ACR was reduced proximally in complicated (1.3 ± 0.18) vs. uncomplicated cases (1.68 ± 0.3; p = 0.023). CONCLUSIONS: FLER allows to image the quantified fluorescence signal in augmented reality and provides a reproducible estimation of bowel perfusion (NCT02626091).

Robotics in flexible endoscopy: current status and future prospects.

PURPOSE OF REVIEW: Advanced endoscopy procedures are technically challenging and require extensive training. Recent technological advances made in computer science and robotics have the potential to enhance the performance of complex intraluminal and transluminal interventions and potentially optimize precision and safety. This review covers the different technologies used for robot-assisted interventions in the gastrointestinal tract, organized according to their clinical availability, and focusing on flexible endoscopy-based systems. RECENT FINDINGS: In the curvilinear gastrointestinal anatomy, robotic technology can enhance flexible endoscopes to augment effectiveness, safety, and therapeutic capabilities, particularly for complex intraluminal and transluminal interventions. Increased visual angles, increased degrees of freedom of instrumentation, optimized navigation, and locomotion, which may lead to a reduced physician learning curve and workload, are promising achievements with the promise to ultimately replace conventional endoscopy techniques for screening and therapeutic endoscopy. SUMMARY: The majority of these devices are not commercially available yet. The best clinical applications are also currently being researched. Nonetheless, robotic assistance may encourage surgeons to use flexible endoscopes to administer surgical therapies and increase interest among gastroenterologists in advanced therapies. Robotics may be a means to overcome the technical obstacles of incisionless natural orifice procedures and favor an increased adoption of complex endoscopic procedures such as third-space therapies.

Fluorescence-enabled assessment of adrenal gland localization and perfusion in posterior retroperitoneoscopic adrenal surgery in a preclinical model.

BACKGROUND: The posterior retroperitoneoscopic adrenal access represents a challenge in orientation and working space creation. The aim of this experimental acute study was to evaluate the impact of computer-assisted quantitative fluorescence imaging on adrenal gland identification and assessment of intraoperative remnant perfusion for adrenal resection in the posterior retroperitoneoscopic approach. METHODS: Six pigs underwent simultaneous (n = 5) or sequential (n = 1) bilateral posterior retroperitoneoscopic adrenalectomy (n = 12). Fluorescence imaging was obtained via intravenous administration of 3 mL of Indocyanine Green (ICG) and by switching the camera systems to near-infrared mode (D-LIGHT P, KARL STORZ; Germany). Fluorescence-based visualization of adrenal glands before vascular division (n = 4), after the main vascular pedicle ligation (negative control, n = 1) or after adrenal resection (n = 7), was followed by completion adrenalectomy. The fluorescence signal intensity dynamics were recorded and analyzed using proprietary software. For each pixel, the slope of fluorescence signal intensity evolution over time was translated into a color-coded perfusion cartography, which was superimposed onto real-time images obtained with the corresponding left and right camera systems. Quantitative fluorescence signal analysis in the regions of interest (ROIs) served to assess adrenal remnant perfusion in divided adrenal glands. RESULTS: In the retroperitoneum, the vascular anatomy was illuminated in fluorescence imaging first. The adrenal glands were promptly highlighted after primary intravenous ICG administration (n = 9) or showed a fluorescence signal intensity increase upon reinjection (n = 3). Quantitative fluorescence analysis showed a statistically significant difference between perfused and ischemic segments in divided glands (p = 0.0156). CONCLUSIONS: Fluorescence imaging provides real-time guidance during minimally invasive adrenal surgery. Prior to dissection, it allows to easily discriminate the adrenal gland from surrounding retroperitoneal structures. After adrenal gland division, ICG injection associated with a computer-assisted quantitative analysis helps to distinguish between well-perfused and ischemic segments. Further studies are underway to establish the correlation between remnant perfusion and viability.

HYPerspectral Enhanced Reality (HYPER): a physiology-based surgical guidance tool.

BACKGROUND: HSI is an optical technology allowing for a real-time, contrast-free snapshot of physiological tissue properties, including oxygenation. Hyperspectral imaging (HSI) has the potential to quantify the gastrointestinal perfusion intraoperatively. This experimental study evaluates the accuracy of HSI, in order to quantify bowel perfusion, and to obtain a superposition of the hyperspectral information onto real-time images. METHODS: In 6 pigs, 4 ischemic bowel loops were created (A, B, C, D) and imaged at set time points (from 5 to 360 min). A commercially available HSI system provided pseudo-color maps of the perfusion status (StO2, Near-InfraRed perfusion) and the tissue water index. An ad hoc software was developed to superimpose HSI information onto the live video, creating the HYPerspectral-based Enhanced Reality (HYPER). Seven regions of interest (ROIs) were identified in each bowel loop according to StO2 ranges, i.e., vascular (VASC proximal and distal), marginal vascular (MV proximal and distal), marginal ischemic (MI proximal and distal), and ischemic (ISCH). Local capillary lactates (LCL), reactive oxygen species (ROS), and histopathology were measured at the ROIs. A machine-learning-based prediction algorithm of LCL, based on the HSI-StO2%, was trained in the 6 pigs and tested on 5 additional animals. RESULTS: HSI parameters (StO2 and NIR) were congruent with LCL levels, ROS production, and histopathology damage scores at the ROIs discriminated by HYPER. The global mean error of LCL prediction was 1.18 ± 1.35 mmol/L. For StO2 values > 30%, the mean error was 0.3 ± 0.33. CONCLUSIONS: HYPER imaging could precisely quantify the overtime perfusion changes in this bowel ischemia model.

Simultaneous computer-assisted assessment of mucosal and serosal perfusion in a model of segmental colonic ischemia.

BACKGROUND: Fluorescence-based enhanced reality (FLER) enables the quantification of fluorescence signal dynamics, which can be superimposed onto real-time laparoscopic images by using a virtual perfusion cartogram. The current practice of perfusion assessment relies on visualizing the bowel serosa. The aim of this experimental study was to quantify potential differences in mucosal and serosal perfusion levels in an ischemic colon segment. METHODS: An ischemic colon segment was created in 12 pigs. Simultaneous quantitative mucosal and serosal fluorescence imaging was obtained via intravenous indocyanine green injection (0.2 mg/kg), using two near-infrared camera systems, and computer-assisted FLER analysis. Lactate levels were measured in capillary blood of the colonic wall at seven regions of interest (ROIs) as determined with FLER perfusion cartography: the ischemic zone (I), the proximal and distal vascularized areas (PV, DV), and the 50% perfusion threshold proximally and distally at the mucosal and serosal side (P50M, P50S, D50M, D50S). RESULTS: The mean ischemic zone as measured (mm) for the mucosal side was significantly larger than the serosal one (56.3 ± 21.3 vs. 40.8 ± 14.9, p = 0.001) with significantly lower lactate values at the mucosal ROIs. There was a significant weak inverse correlation between lactate and slope values for the defined ROIs (r = - 0.2452, p = 0.0246). CONCLUSIONS: Mucosal ischemic zones were larger than serosal zones. These results suggest that an assessment of bowel perfusion from the serosal side only can underestimate the extent of ischemia. Further studies are required to predict the optimal resection margin and anastomotic site.

Hybrid fluorescent magnetic gastrojejunostomy: an experimental feasibility study in the porcine model and human cadaver.

BACKGROUND: Laparoscopic gastrojejunostomies are time consuming and require a specific training. Alternatively, sutureless anastomosis can be achieved using endoscopically delivered magnetic rings. Our aim was to assess the feasibility and reproducibility of an endo-laparoscopic gastrojejunostomy technique, using a pair of magnets coated with a near-infrared fluorescent biocompatible polymeric material. METHODS: Five pigs (3 acute and 2 survival models) and one human anatomical specimen were included. In the survival models, the distal ring was inserted into the duodenum endoscopically, and it was fixed to a thread clipped to the gastric mucosa. Twenty-four hours later, a two-port laparoscopy was performed using a near-infrared (NIR) laparoscope. The magnet position in the jejunum was detected with the transluminal fluorescence of the dye. Magnetic interaction with the metallic tip of the laparoscopic grasper allowed to capture the ring and bring the bowel loop to the future anastomotic site on the gastric wall. The proximal magnet was inserted into the stomach endoscopically and released when magnetic interaction started, allowing for a precise connection with the distal ring. The animals were followed up for 12 days and underwent control endoscopies and radiograms. In the acute animals, the anastomotic procedure was repeated 24 times. Finally, the procedure was performed in the human anatomical specimen. RESULTS: There were no technical problems, and magnetic connection could be precisely directed at both the anterior and posterior gastric walls. No complications occurred during the survival period and the anastomoses were patent on day 5. Transluminal fluorescence enabled a rapid detection of the magnet. CONCLUSIONS: Hybrid-reduced port magnetic gastrojejunostomy using a pair of fluorescently coated magnetic rings was feasible, reproducible, and easy to perform in both porcine and cadaver models.

Acute abdomen in patients with SARS-CoV-2 infection or co-infection.

PURPOSE: Patients with an acute abdomen require emergency surgery. SARS-CoV-2 infection can affect multiple organ systems, including the digestive tract. Little is known about the consequences of COVID-19 infection in emergency surgical patients. METHODS: Perioperative data for COVID-19 patients undergoing emergency surgery from March 1, 2020, to May 23, 2020 were collected prospectively (NCT04323644). RESULTS: During this period, 215 patients underwent surgery, including 127 patients in an emergency setting, of whom 13 (10.2%) had COVID-19. Two scenarios were identified: (a) patients who were admitted to a hospital for an acute surgical condition with a concomitant diagnosis of COVID-19, and (b) patients with severe COVID-19 developing acute abdominal pathologies during their hospital stay. When compared with those in group B, patients in group A globally recovered better, with a lower mortality rate (14.3% vs. 33.3%), lower ARDS rate (28.5% vs. 50.0%), less rates of preoperative invasive ventilation (14.3% vs. 50.0%) and postoperative invasive ventilation (28.5% vs. 100.0%), and a shorter duration of invasive ventilation. No causality between SARS-CoV-2 infection and gastrointestinal affliction was found. CONCLUSION: Our observations underline that mild co-infection with COVID-19 did not result in more complications for emergency abdominal surgery. Howe, an acute abdomen during severe COVID-19 infection was part of an unfavorable prognosis.

Development of an ontology for laparoscopic transabdominal adrenalectomy via a comprehensive modified Delphi survey and its validation on a multicentric pilot data set for surgical training and future video analysis with machine learning algorithms.

Surgical technique is essential to ensure safe minimally invasive adrenalectomy. Due to the relative rarity of adrenal surgery, it is challenging to ensure adequate exposure in surgical training. Surgical video analysis supports auto-evaluation, expert assessment and could be a target for automatization. The developed ontology was validated by a European expert consensus and is applicable across the surgical techniques encountered in all participating centres, with an exemplary demonstration in bi-centric recordings. Standardization of adrenalectomy video analysis may foster surgical training and enable machine learning training for automated safety alerts.

Enabling single-site laparoscopy: the SPORT platform.

BACKGROUND: The Single Port Orifice Robotic Technology (SPORT) Surgical System by Titan Medical Inc. is designed to overcome the inherent challenges of minimally invasive single-access procedures. The aim of this preclinical study was to evaluate the feasibility of various digestive surgery procedures using this novel surgical robotic platform. METHODS: A total of 12 minimally invasive procedures were performed on six pigs (5 cholecystectomies, 3 Nissen fundoplications, 1 splenectomy and 1 hepatic pedicle dissection) and on one human cadaver (1 cholecystectomy and 1 Nissen fundoplication), by four laparoscopic surgeons. The usability of the device was assessed by means of the modified objective structured assessment of technical skills (OSATS) score that was calculated and analyzed by two independent observers on the recorded videos. Surgeon feedback and recommendations were systematically recorded. RESULTS: All procedures were successfully completed with the SPORT system. In general, surgeons reported to appreciate the intuitive interface and controls, the high-resolution 3D imaging, the dexterity of the end-effectors, and the ergonomic open control platform. Some features requiring optimization were also identified. The modified OSATS score demonstrated a learning curve effect for all device-related tasks. CONCLUSIONS: A variety of abdominal procedures could be safely completed with the current SPORT prototype, in the preclinical setting. This preliminary feasibility experience is promising and encourages further development of single-port robotically assisted surgery.

Discrimination between arterial and venous bowel ischemia by computer-assisted analysis of the fluorescent signal.

BACKGROUND: Arterial blood supply deficiency and venous congestion both play a role in anastomotic complications. Our aim was to evaluate a software-based analysis of the fluorescence signal to recognize the patterns of bowel ischemia. METHODS: In 18 pigs, two clips were applied on the inferior mesenteric artery (group A: n = 6) or vein (group V: n = 6) or on both (group A-V: n = 6). Three regions of interest (ROIs) were identified on the sigmoid: P = proximal to the first clip; C = central, between the two clips; and D = distal to the second clip. Indocyanine Green was injected intravenously. The fluorescence signal was captured by means of a near-infrared laparoscope. The time-to-peak (seconds) and the maximum fluorescence intensity were recorded using software. A normalized fluorescence intensity unit (NFIU: 0-to-1) was attributed, using a reference card. The NFIU's over-time variations were computed every 10 min for 50 min. Capillary lactates were measured on the sigmoid at the 3 ROIs. Various machine learning algorithms were applied for ischemia patterns recognition. RESULTS: The time-to-peak at the ischemic ROI C was significantly longer in group A versus V (20.1 ± 13 vs. 8.43 ± 3.7; p = 0.04) and in group A-V versus V (20.71 ± 11.6 vs. 8.43 ± 3.7; p = 0.03). The maximal NIFU at ROI C, was higher in the V group (1.01 ± 0.21) when compared to A (0.61 ± 0.11; p = 0.002) and A-V (0.41 ± 0.2; p = 0.0005). Capillary lactates at ROI C were lower in V (1.3 ± 0.6) than in A (1.9 ± 0.5; p = 0.0071), and A-V (2.6 ± 1.5; p = 0.034). The K nearest neighbor and the Linear SVM algorithms provided both an accuracy of 75% in discriminating between A versus V and 85% in discriminating A versus A-V. The accuracy dropped to 70% when the ML had to identify the ROI and the type of ischemia simultaneously. CONCLUSIONS: The computer-assisted dynamic analysis of the fluorescence signal enables the discrimination between different bowel ischemia models.

Correction to: Discrimination between arterial and venous bowel ischemia by computer-assisted analysis of the fluorescent signal.

In the original version, Ines Gockel was omitted as a coauthor. The complete author listing is corrected here.

New intraoperative imaging technologies: Innovating the surgeon's eye toward surgical precision.

Imaging is one of the pillars for the ongoing evolution of surgical oncology toward a precision paradigm. In the present overview, some established or emerging intraoperative imaging technologies are described in light of the vision and experience of our group in image-guided surgery, focusing on digestive surgical oncology.

Transcutaneous laryngeal ultrasonography (TLUS) as an alternative to direct flexible laryngoscopy (DFL) in the perioperative evaluation of the vocal cord mobility in thyroid surgery.

PURPOSE: Direct flexible laryngoscopy (DFL) is the golden standard to evaluate the vocal cord (VC) function in thyroid and parathyroid surgery pre- and postoperatively. Transcutaneous laryngeal ultrasonography (TLUS) could represent an alternative to the DFL and has been evaluated in the present study comparing the results of both methods performed at two referral centers for endocrine pathologies. METHODS: In the setting of a retrospective study, 668 patients (560 female, 118 male; mean age 50.3 ± 14.2) were included from two tertiary referral centers of endocrine surgery. In all patients, TLUS was performed pre- and postoperatively prior to transnasal DFL, which served as a golden standard. TLUS was performed by B-scan (probe 5-13 MHz, aperture 40 mm). RESULTS: Preoperative visualization of the vocal cords by TLUS was possible in 526 patients (78.7%). Due to the frequent thyroid cartilage calcification (TCC) in male patients, a significant difference in the visualization rate was found between female and male (88.7% vs. 26.8%) [p < 0.0001]. Additionally, the visualization rate was inversely related to the patient's age [p < 0.001]. The sensitivity of preoperative TLUS was found to be 66.7%, the specificity 100%. DFL confirmed a postoperative palsy in 34 out of 40 patients with supposed abnormal vocal cord mobility at TLUS and demonstrated a palsy in four more cases with supposed regular mobility at TLUS. Therefore, the sensitivity of postoperative TLUS was 86%, the specificity of 99.1%, positive predictive value 89.4%, negative predictive value 98.7%. CONCLUSIONS: TLUS could represent an alternative for the evaluation of vocal cords mobility. This method has the potential to replace the DFL in the majority of cases, especially in female patients. Nevertheless, DFL is still necessary in about 20% of the patients with failed visualization at TLUS.