Single port component separation: endoscopic external oblique release for complex ventral hernia repair.

BACKGROUND: Component separation (CS) is a technique which mobilizes flaps of innervated, vascularized tissue, enabling closure of large ventral hernia defects using autologous tissue. Disadvantages include extensive tissue dissection when creating these myofascial advancement flaps, with potential consequences of significant post-operative skin and wound complications. This study examines the benefit of a novel, ultra-minimally invasive single port anterior CS technique. METHODS: This was a prospective study of 16 external oblique (EO) releases performed in 9 patients and 4 releases performed in 3 fresh frozen cadavers. All patients presented with recurrent complex ventral hernias, and were administered preoperative Botulinum Toxin A to their lateral oblique muscles to facilitate defect closure. At the time of elective laparoscopic repair, patients underwent single port endoscopic EO release using a single 20-mm incision on each side of the abdomen. Measurements were taken using real-time ultrasound. Postoperatively, patients underwent serial examination and abdominal CT assessment. RESULTS: Single port endoscopic EO release achieved a maximum of 50-mm myofascial advancement per side (measured at the umbilicus). No complications involving wound infection, hematoma, or laxity/bulge have been noted. All patients proceeded to laparoscopic or laparoscopic-open-laparoscopic intraperitoneal mesh repair of their hernia, with no hernia recurrences to date. CONCLUSIONS: Single port endoscopic EO release holds potential as an adjunct in the repair of large ventral hernia defects. It is easy to perform, is safe and efficient, and entails minimal disruption of tissue planes and preserves abdominal wall perforating vessels. It requires only one port-sized incision on each side of the abdomen, thus minimizing potential for complications. Further detailed quantification of advancement gains and morbidity from this technique is warranted, both with and without prior administration of Botulinum Toxin A to facilitate closure.

Preoperative Botulinum toxin A enabling defect closure and laparoscopic repair of complex ventral hernia.

INTRODUCTION: Operative management of complex ventral hernia still remains a significant challenge for surgeons. Closure of large defects in the unprepared abdomen has serious pathophysiological consequences due to chronic contraction and retraction of the lateral abdominal wall muscles. We report outcomes of 56 consecutive patients who had preoperative Botulinum toxin A (BTA) abdominal wall relaxation facilitating closure and repair. METHODS: This was a prospective observational study of 56 patients who underwent ultrasound-guided BTA into the lateral abdominal oblique muscles prior to elective ventral hernia repair between November 2012 and January 2017. Serial non-contrast abdominal CT imaging was performed to evaluate changes in lateral oblique muscle length and thickness. All hernias were repaired laparoscopically, or laparoscopic-open-laparoscopic (LOL) using intraperitoneal onlay mesh. RESULTS: 56 patients received BTA injections at predetermined sites to the lateral oblique muscles, which were well tolerated. Mean patient age was 59.7 years, and mean BMI was 30.9 kg/m2 (range 21.8-54.0). Maximum defect size was 24 × 27 cm. A subset of 18 patients underwent preoperative pneumoperitoneum as an adjunct procedure. A comparison of pre-BTA to post-BTA imaging demonstrated an increase in mean lateral abdominal wall length from 16.1 cm to 20.1 cm per side, a mean gain of 4.0 cm/side (range 1.0-11.7 cm/side) (p < 0.0001). This corresponds to an unstretched mean length gain of 8.0 cm of the lateral abdominal wall. Laparoscopic/LOL primary closure was achieved in all cases, with no clinical evidence of raised intra-abdominal pressures. One patient presented with a new fascial defect 26 months post-operative. CONCLUSION: Preoperative BTA to the lateral abdominal wall muscles is a safe and effective technique for the preparation of patients prior to operative management of complex ventral hernias. BTA temporary flaccid paralysis relaxes, elongates and thins the chronically contracted abdominal musculature. This in turn reduces lateral traction forces facilitating laparoscopic repair and fascial closure of large defects under minimal tension.

Preoperative chemical component relaxation using Botulinum toxin A: enabling laparoscopic repair of complex ventral hernia.

BACKGROUND: Repair of complex ventral hernia can be very challenging for surgeons. Closure of large defects can have serious pathophysiological consequences. Botulinum toxin A (BTA) has recently been described to provide flaccid paralysis to abdominal muscles prior to surgery, facilitating closure and repair. METHODS: This was a prospective observational study of 32 patients who underwent ultrasound-guided injections of BTA to the lateral abdominal wall muscles prior to elective repair of complex ventral hernia between January 2013 and December 2015. Serial non-contrast abdominal CT imaging was performed to measure changes in fascial defect size, abdominal wall muscle length and thickness. All hernias were repaired laparoscopically or laparoscopic-assisted with placement of intra-peritoneal mesh. RESULTS: Thirty-two patients received BTA injections which were well tolerated with no complications. A comparison of baseline (preBTA) CT imaging with postBTA imaging demonstrated an increase in mean baseline abdominal wall length from 16.4 to 20.4 cm per side (p < 0.0001), which translates to a gain in mean transverse length of the unstretched anterolateral abdominal wall muscles of 4.0 cm/side (range 0-11.7 cm/side). Fascial closure was achieved in all cases, with no instances of raised intra-abdominal pressures or its sequelae, and there have been no hernia recurrences to date. CONCLUSIONS: Preoperative BTA injection to the muscles of the anterolateral abdominal wall is a safe and effective technique for the preoperative preparation of patients prior to laparoscopic mesh repair of complex ventral hernia. This technique elongates and thins the contracted and retracted musculature, enabling closure of large defects.

Expression of S100A2 calcium-binding protein predicts response to pancreatectomy for pancreatic cancer.

BACKGROUND & AIMS: Current methods of preoperative staging and predicting outcome following pancreatectomy for pancreatic cancer (PC) are inadequate. We evaluated the utility of multiple biomarkers from distinct biologic pathways as potential predictive markers of response to pancreatectomy and patient survival. METHODS: We assessed the relationship of candidate biomarkers known, or suspected, to be aberrantly expressed in PC, with disease-specific survival and response to therapy in a cohort of 601 patients. RESULTS: Of the 17 candidate biomarkers examined, only elevated expression of S100A2 was an independent predictor of survival in both the training (n = 162) and validation sets (n = 439; hazard ratio [HR], 2.19; 95% confidence interval [CI]: 1.48-3.25; P < .0001) when assessed in a multivariate model with clinical variables. Patients with high S100A2 expressing tumors had no survival benefit with pancreatectomy compared with those with locally advanced disease, whereas those without high S100A2 expression had a survival advantage of 10.6 months (19.4 vs 8.8 months, respectively) and a HR of 3.23 (95% CI: 2.39-4.33; P < .0001). Of significance, patients with S100A2-negative tumors had a significant survival benefit from pancreatectomy even in the presence of involved surgical margins (median, 15.7 months; P = .0007) or lymph node metastases (median, 17.4 months; P = .0002). CONCLUSIONS: S100A2 expression is a good predictor of response to pancreatectomy for PC and suggests that high S100A2 expression may be a marker of a metastatic phenotype. Prospective measurement of S100A2 expression in diagnostic biopsy samples has potential clinical utility as a predictive marker of response to pancreatectomy and other therapies that target locoregional disease.

Real time intraoperative confocal laser microscopy-guided surgery.

OBJECTIVE: To assess the potential utility of in vivo histologic surface and subsurface imaging in real-time using the Optiscan confocal laser microscope to detect diseased tissue at the time of surgery. SUMMARY BACKGROUND DATA: The goal of surgical treatment of diseases such as cancer is complete microscopic resection of diseased tissue; however, current methods for the assessment of extent of disease at the time of surgery are inadequate. METHODS: We assessed the potential of the Optiscan confocal laser microscope, a new device developed for real-time in vivo histologic surface and subsurface imaging during surgery. RESULTS: Intravenous Fluorescein Sodium contrast enabled visualization of cellular and architectural morphology of intra-abdominal organs with magnification equivalent to light microscopy and enabled differentiation between normal organs and disease. CONCLUSIONS: Real time intraoperative confocal microscopy has significant potential application in detecting disease, and influencing decision-making at the time of surgery.

Synoptic reporting improves histopathological assessment of pancreatic resection specimens.

AIM: We examined whether introduction of a standardised pancreatic cancer minimum data set improved the reporting of key pathological features across multiple institutions. METHODS: From seven different pathology departments that are members of the New South Wales Pancreatic Cancer Network, 109 free text reports and 68 synoptic reports were compared. RESULTS: AJCC stage could not be inferred from 44% of free text reports, whereas stage was reported in all 68 synoptic reports. In the free text reports 28 different names were used to designate margins. All margins were reported in only 12 (11%) of the free text reports compared with 64 (94%) of the synoptic reports (p = 0.0011). The presence or absence of lymphovascular or perineural invasion was reported in 72 (66%) and 92 (84%) of free text reports, respectively. In contrast, lymphovascular space and perineural invasion were reported in all synoptic reports (p = 0.0011 and p = 0.0058). CONCLUSION: We conclude that synoptic reporting of pancreatic resections without any other intervention increases the information contained within histopathology reports. Therefore, the introduction of minimal data set synoptic reports is a simple and feasible mechanism to immediately improve reporting for pancreatectomy specimens.

A systematic review of skills transfer after surgical simulation training.

OBJECTIVE: To determine whether skills acquired by simulation-based training transfer to the operative setting. SUMMARY BACKGROUND DATA: The fundamental assumption of simulation-based training is that skills acquired in simulated settings are directly transferable to the operating room, yet little evidence has focused on correlating simulated performance with actual surgical performance. METHODS: A systematic search strategy was used to retrieve relevant studies. Inclusion of articles was determined using a predetermined protocol, independent assessment by 2 reviewers, and a final consensus decision. Only studies that reported on the use of simulation-based training for surgical skills training, and the transferability of these skills to the operative setting, were included. RESULTS: Ten randomized controlled trials and 1 nonrandomized comparative study were included in this review. In most cases, simulation-based training was in addition to normal training programs. Only 1 study compared simulation-based training with patient-based training. For laparoscopic cholecystectomy and colonoscopy/sigmoidoscopy, participants who received simulation-based training before undergoing patient-based assessment performed better than their counterparts who did not receive previous simulation training, but improvement was not demonstrated for all measured parameters. CONCLUSIONS: Skills acquired by simulation-based training seem to be transferable to the operative setting. The studies included in this review were of variable quality and did not use comparable simulation-based training methodologies, which limited the strength of the conclusions. More studies are required to strengthen the evidence base and to provide the evidence needed to determine the extent to which simulation should become a part of surgical training programs.

Pancreatitis from intra-gastric balloon insertion: Case report and literature review.

INTRODUCTION: Intra-Gastric Balloon (IGB) is increasingly used as a non-operative management strategy in bariatric patients. However, as IGB use has become more prevalent, new potentially life-threatening adverse effects have emerged. We report a case of IGB-related acute pancreatitis from a tertiary referral hospital. A literature review of electronic databases was conducted to identify other cases PRESENTATION OF CASE: A 20-year-old female presented to the emergency department with acute onset of epigastric pain on day-1 post-insertion of an IGB (Orbera®). The diagnosis of acute pancreatitis was made on the basis of the clinical picture, with radiological and serological confirmation. Complete resolution of symptoms promptly followed endoscopic removal of the balloon. DISCUSSION: We examine all prior reported cases of IGB associated pancreatitis in the literature, as well as the impact of the particular balloon subtypes. Mass effect of the device on the pancreas or dislodgement of the rigid catheter into the second part of the duodenum appear to be the underlying cause in all cases. While there were no deaths reported, major sequelae have been noted, including presence of mucosal ischemia and failure to retrieve the balloon endoscopically, necessitating laparotomy. CONCLUSION: Although the incidence of IGB-induced pancreatitis is still rare, this complication which must be highlighted as a potentially serious adverse outcome.

Characterisation of a novel light activated adhesive scaffold: Potential for device attachment.

The most common methods for attaching a device to the internal tissues of the human body are via sutures, clips or staples. These attachment techniques require penetration and manipulation of the tissue. Tears and leaks can often be a complication post-attachment, and scarring usually occurs around the attachment sites. To resolve these issues, it is proposed to develop a soft tissue scaffold impregnated with Rose Bengal/Chitosan solution (RBC-scaffold, 0.01% w/v Rose Bengal, 1.7% w/v Medium Molecular Weight Chitosan). This scaffold will initially attach to the tissue via a light activation method. The light activates the dye in the scaffold which causes cross-links to form between the scaffold and tissue, thus adhering them together. This is done without mechanically manipulating the surrounding tissue, thus avoiding the issues associated with current techniques. Eventually, the scaffold will be resorbed and tissue will integrate for long-term attachment. A variety of tests were performed to characterise the RBC-scaffold. Porosity, interconnectivity, and mechanical strength were measured. Light activation was performed with a broad spectrum (380-780nm) 10W LED lamp exposed to various time lengths (2-15min, Fluence range 0.4-3J/cm(2) ). Adhesive strength of the light-activated bond was measured with lap-shear tests performed on porcine stomach tissue. Cell culture viability was also assessed to confirm tissue integration potential. These properties were compared to Variotis™, an aliphatic polyester soft tissue scaffold which has proven to be viable for soft tissue regeneration. The RBC-scaffolds were found to have high porosity (86.46±2.95%) and connectivity, showing rapid fluid movement. The elastic modulus of the RBC-scaffolds (3.55±1.28MPa) was found to be significantly higher than the controls (0.15±0.058MPa, p<0.01) and approached reported values for human gastrointestinal tissue (2.3MPa). The maximum adhesion strength achieved of the RBC-scaffolds was 8.61±2.81kPa after 15min of light activation, this is comparable to the adhesion strength of fibrin glue on scaffolds. Cell attachment was seen to be similar to the controls, but cells appeared to have better cell survivability. In conclusion, the RBC-scaffolds show promise for use as a novel light activated attachment device with potential applications in attaching an anti-reflux valve in the lower oesophagus and also in wound healing applications for stomach ulcers.

Virtual reality simulators: current status in acquisition and assessment of surgical skills.

Medical technology is currently evolving so rapidly that its impact cannot be analysed. Robotics and telesurgery loom on the horizon, and the technology used to drive these advances has serendipitous side-effects for the education and training arena. The graphical and haptic interfaces used to provide remote feedback to the operator--by passing control to a computer--may be used to generate simulations of the operative environment that are useful for training candidates in surgical procedures. One additional advantage is that the metrics calculated inherently in the controlling software in order to run the simulation may be used to provide performance feedback to individual trainees and mentors. New interfaces will be required to undergo evaluation of the simulation fidelity before being deemed acceptable. The potential benefits fall into one of two general categories: those benefits related to skill acquisition, and those related to skill assessment. The educational value of the simulation will require assessment, and comparison to currently available methods of training in any given procedure. It is also necessary to determine--by repeated trials--whether a given simulation actually measures the performance parameters it purports to measure. This trains the spotlight on what constitutes good surgical skill, and how it is to be objectively measured. Early results suggest that virtual reality simulators have an important role to play in this aspect of surgical training.

The production of audiovisual teaching tools in minimally invasive surgery.

OBJECTIVES: Audiovisual learning resources have become valuable adjuncts to formal teaching in surgical training. This report discusses the process and challenges of preparing an audiovisual teaching tool for laparoscopic cholecystectomy. The relative value in surgical education and training, for both the creator and viewer are addressed. DESIGN/SETTING: This audiovisual teaching resource was prepared as part of the Master of Surgery program at the University of Sydney, Australia. The different methods of video production used to create operative teaching tools are discussed. RESULTS: Collating and editing material for an audiovisual teaching resource can be a time-consuming and technically challenging process. However, quality learning resources can now be produced even with limited prior video editing experience. With minimal cost and suitable guidance to ensure clinically relevant content, most surgeons should be able to produce short, high-quality education videos of both open and minimally invasive surgery. CONCLUSIONS: Despite the challenges faced during production of audiovisual teaching tools, these resources are now relatively easy to produce using readily available software. These resources are particularly attractive to surgical trainees when real time operative footage is used. They serve as valuable adjuncts to formal teaching, particularly in the setting of minimally invasive surgery.

Margin clearance and outcome in resected pancreatic cancer.

PURPOSE: Current adjuvant therapies for pancreatic cancer (PC) are inconsistently used and only modestly effective. Because a high proportion of patients who undergo resection for PC likely harbor occult metastatic disease, any adjuvant trials assessing therapies such as radiotherapy directed at locoregional disease are significantly underpowered. Stratification based on the probability (and volume) of residual locoregional disease could play an important role in the design of future clinical trials assessing adjuvant radiotherapy. PATIENTS AND METHODS: We assessed the relationships between margin involvement, the proximity to operative resection margins and outcome in a cohort of 365 patients who underwent operative resection for PC. RESULTS: Microscopic involvement of a resection margin by tumor was associated with a poor prognosis. Stratifying the minimum clearance of resection margins by 0.5-mm increments demonstrated that although median survival was no different to clear margins based on these definitions, it was not until the resection margin was clear by more than 1.5 mm that optimal long-term survival was achieved. CONCLUSION: These data demonstrate that a margin clearance of more than 1.5 mm is important for long-term survival in a subgroup of patients. More aggressive therapeutic approaches that target locoregional disease such as radiotherapy may be beneficial in patients with close surgical margins. Stratification of patients for entry onto future clinical trials based on this criterion may identify those patients who benefit from adjuvant radiotherapy.

A novel approach to high definition, high-contrast video capture in abdominal surgery.

OBJECTIVE: The aim of this study was to define the best available option for video capture of surgical procedures for educational and archival purposes, with a view to identifying methods of capturing high-quality footage and identifying common pitfalls. SUMMARY BACKGROUND DATA: Several options exist for those who wish to record operative surgical techniques on video. While high-end equipment is an unnecessary expense for most surgical units, several techniques are readily available that do not require industrial-grade audiovisual recording facilities, but not all are suited to every surgical application. METHODS: We surveyed and evaluated the available technology for video capture in surgery. Our evaluation included analyses of video resolution, depth of field, contrast, exposure, image stability, and frame composition, as well as considerations of cost, accessibility, utility, feasibility, and economies of scale. RESULTS: Several video capture options were identified, and the strengths and shortcomings of each were catalogued. None of the commercially available options was deemed suitable for high-quality video capture of abdominal surgical procedures. A novel application of off-the-shelf technology was devised to address these issues. CONCLUSIONS: Excellent quality video capture of surgical procedures within deep body cavities is feasible using commonly available equipment and technology, with minimal technical difficulty.