Endoluminal Sphincter Augmentation with the MUSE™ System and GERDX™ System in the Treatment of Gastroesophageal Reflux Disease: A New Impact?

To bridge the gap between the long-term intake of proton pump inhibitors (PPIs) and the potential risks of laparoscopic fundoplication, a number of endoscopic procedures for the treatment of gastro-esophageal reflux disease (GERD) have been developed over the past 30 years. Because of the minimally invasive approach, short operative time, and efficacy in selected patients, endoluminal sphincter augmentation appears to be highly attractive. However, most early devices have proven to be unsafe or failed to provide long-term symptom relief. Accordingly, products for endoluminal sphincter augmentation have undergone several modifications to achieve an increased lower esophageal sphincter (LES) baseline pressure to re-establish the LES as an efficacious anti-reflux barrier. This paper reviews and discusses the two latest products for endoluminal sphincter augmentation, the MUSE™ device (Medigus, Ltd., Omer, Israel) and the GERDX™ system (G-SURG GmbH, Seeon-Seebruck, Germany). While the currently available literature has proven their effectiveness in principle, long-term results are lacking. Further studies and developments are necessary to determine whether these two new devices will truly impact GERD therapy.

Endoscopic rendez-vous reconstruction of complete biliary obstruction

BACKGROUND AND STUDY AIMS

Complete biliary strictures normally require surgical intervention. We describe an alternative, minimally invasive endoscopic/percutaneous rendez-vous technique for the reconstruction of complete benign biliary strictures.

PATIENTS AND METHODS

Complete biliary strictures were reconstructed in four patients using a rendez-vous percutaneous-endoscopic or percutaneous-percutaneous route guided by fluoroscopic and visual (transillumination) control.

RESULTS

All four patients were treated successfully and safely with the rendez-vous technique. Complications were caused by the preliminary creation, dilatation and maturation of the percutaneous tract.

CONCLUSION

This technique may offer a good alternative to surgical bilio-enteric anastomosis in experienced hands. The long term course of the patients treated remains to be seen.

An evaluation of a surgical telepresence system for an intrahospital local area network

summary

We evaluated a digital telepresence system in an operating theatre (OR) environment which enabled a consultant to join the surgical team from a remote site by audiovisual communication. The system is based on video transmission using a streaming technique, with a server and a client connected via a local area network (LAN). Two cameras can be remotely controlled: one camera is built into the OR lamp and a second, laparoscopic camera is mounted on a robotic arm. Another feature of the system is teledemonstration, which permits the remote consultant to demonstrate points of particular interest. We evaluated the system clinically in 237 cases. In 28 cases (12%), telepresence could not be established for various reasons, mainly human failure. In 42 cases (18%), the full potential of telepresence was used. Technical evaluation showed that a data rate of 2 Mbit/s provides sufficient audio and video quality, as well as reliable teledemonstration. The data transmission delay was acceptable for clinical purposes (video 0.92 s, audio 0.6s from OR to client, audio 0.7s from client to OR). The study showed that telepresence is a promising means of providing highly specialized expertise within the OR.

Esophageal bougination: a novel ex vivo endoscopic training model correlated with clinical data

BACKGROUND

Esophageal bougination is a worldwide standard endoscopic procedure. Clinical methods and recommendations are based on clinical experiences only. Mechanical properties have never been described. Aim of the study was to establish a realistic ex vivo training model. Therefore, detailed assessment of relevant mechanical features of esophageal bougination should be evaluated ex vivo and in patient setting and correlated against.

PATIENTS AND METHODS

A three-step concept was used to evaluate mechanical properties at stenosis level. First, insertion forces were evaluated in an ex vivo linear single stenosis model during steady mechanical insertion. Second, adding friction and properties of the pharynx and upper esophagus, the model was integrated in an artificial endoscopic training model (ELITE training model). Third, in vivo measurements were taken to correlate ex vivo data with parameters of a realistic patient setting.

RESULTS

With the presented setup, we were able to assess insertion force and pressure levels in an artificial stricture using different sizes of commercially available standard bougies. In all models, there was a relevant increase in insertion force with higher stricture pressure levels. Insertion force levels in the ELITE model show higher levels compared to the linear stenosis model. Having regard to the maximum forces in patients, there is also a constant increase in mean insertion force according to higher bougie sizes, but lower forces were measured as in the ELITE model.

DISCUSSION

The applied models are suitable to appraise mechanical properties of esophageal bougination in an ex vivo model and patient setting. Forces could be constituted reliable, significant increase was documented according to stenosis level and results were comparable to patient data. This was comparable to patient data. Further clinical evaluation in different kinds of stenosis is necessary.

Wireless live streaming video of surgical operations: an evaluation of communication quality

We evaluated a mobile video system for surgical teleconsultation. A video streaming server in the operating room transmitted video and audio to a hand-held computer (personal digital assistant [PDA]) over a wireless local area network. Two groups of 20 surgeons (each with 12 qualified surgeons and eight surgeons between the 2nd and the 4th year of training) participated in the tests. For voice transmission, correct understanding of numbers was achieved in 100% of the cases ( n = 1000) and 98% of medical terms ( n = 400). The quality of the video displayed on the PDA was assessed by the recognition of different operating room scenarios. Only 62% (SD 17) of the structures were identified clearly on the hand-held device ( n = 400). The accuracy improved to 78% (SD 15) ( n = 400) if the same scenario was observed on a larger (50 cm) video screen ( p < 0.001). Accuracy was significantly better if audio conversation was possible. The quality evaluation by the consultants showed that the PDA display size and quality were sufficient for clinical use.

Pharyngeal pH monitoring in gastrectomy patients - what do we really measure?

AIM

Diagnosis of laryngopharyngeal reflux (LPR) has dramatically increased over the last years. For diagnosis of gastroesophageal reflux, a newly designed pharyngeal probe (Dx-pH) was recently introduced. It is also recommended to guide therapy decision in antireflux surgery. However, diagnostic results are questionable. Therefore, we establish a reliable reference group with asymptomatic patients after total gastrectomy and, thus, complete extinction of gastric acid production.

METHODS

Pharyngeal pH monitoring was performed in 10 consecutive patients with history of total gastrectomy. All patients were off proton pump inhibitor (PPI) therapy and followed a non-acid diet during the complete measurement period.

RESULTS

All procedures were performed without any complication. Six of the 10 asymptomatic gastrectomy patients (60%) had pathological results derived from the validated reference values (Ryan score) in pharyngeal pH monitoring.

CONCLUSION

Pathological pH values assessed by the Dx-pH device, usually interpreted as pathological aerosolized acidic gastroesophageal and/or laryngopharyngeal reflux, are obviously dissociated from gastric acid production. Further studies are required to determine diagnostic value of the new system. Therefore, the pharyngeal pH monitoring system seems currently not to be useful to guide any diagnostic or therapeutic decisions, in particular if surgical therapy is considered.

Endoluminal perforation of a magnetic antireflux device

BACKGROUND

The history of surgical antireflux treatment is coined by the search for better alternatives to Nissen fundoplication. Implantable devices are one option, beginning with the "Angelchik" prosthesis 30 years ago. However, this procedure was left soon because of the high rate of foreign body connected problems (migration, perforation). A modern approach is a magnetic sphincter augmentation device (LINX Reflux Management System, Torax Medical, Shoreview, MN, USA), a magnetic chain which is implanted laparoscopically. Advantages reported are simplicity to apply and good results in reflux control, with up to now only rare complication rates as reported in the literature (Lipham et al. in Dis Esophagus, 2014).

METHODS

We report one case of erosion of the esophagus by a LINX system resulting in severe dysphagia.

RESULTS

A complete endoluminal removal could be achieved by a prototype OTSC-clip remover. Complete remission could be achieved. The technique is presented in detail (video).

CONCLUSIONS

In principle, total endoscopic removal of the LINX device is feasible in case of major erosion.

The "Iceberg Phenomenon": As Soon as One Technological Problem in NOTES Is Solved, the Next One Appears!

PURPOSE

Though already proclaimed about 7 years ago, natural orifice transluminal endoscopic surgery (NOTES) is still in its early stages. A multidisciplinary working team tried to analyze the technical obstacles and identify potential solutions.

METHODS

After a comprehensive review of the literature, a group of 3 surgeons, 1 gastroenterologist, 10 engineers, and 1 representative of biomedical industry defined the most important deficiencies within the system and then compiled as well as evaluated innovative technologies that could be used to help overcome these problems. These technologies were classified with regard to the time needed for their implementation and associated hindrances, where priority is based on the level of impact and significance that it would make.

RESULTS

Both visualization and actuation require significant improvement. Advanced illumination, mist elimination, image stabilization, view extension, 3-dimensional stereoscopy, and augmented reality are feasible options and could optimize visual information. Advanced mechatronic platforms with miniaturized, powerful actuators, and intuitive human-machine interfaces could optimize dexterity, as long as enabling technologies are used. The latter include depth maps in real time, precise navigation, fast pattern recognition, partial autonomy, and cognition systems.

CONCLUSION

The majority of functional deficiencies that still exist in NOTES platforms could be overcome by a broad range of already existing or emerging enabling technologies. To combine them in an optimal manner, a permanent dialogue between researchers and clinicians is mandatory.

Developments in flexible endoscopic surgery: a review

Flexible endoscopy is increasingly developing into a therapeutic instead of a purely diagnostic discipline. Improved visualization makes early lesions easily detectable and allows us to decide ad hoc on the required treatment. Deep enteroscopy allows the exploration of even the small bowel - for long a "white spot" for gastrointestinal endoscopy - and to perform direct treatment. Endoscopic submucosal dissection is a considerable step forward in oncologically correct endoscopic treatment of (early) malignant lesions. Though still technically challenging, it is increasingly facilitated by new manipulation techniques and tools that are being steadily optimized. Closure of wall defects and hemostasis could be improved significantly. Even the anatomy beyond the gastrointestinal wall is being explored by the therapeutic use of endoluminal ultrasound. Endosonographic-guided surgery is not only a suitable fallback solution if conventional endoscopic retrograde cholangiopancreatography fails, but even makes necrosectomy procedures, abscess drainage, and neurolysis feasible for the endoscopist. Newly developed endoscopic approaches aim at formerly distinctive surgical domains like gastroesophageal reflux disease, appendicitis, and cholecystitis. Combined endoscopic/laparoscopic interventional techniques could become the harbingers of natural orifice transluminal endoscopic surgery, whereas pure natural orifice transluminal endoscopic surgery is currently still in its beginnings.

What Do We Really Need? Visions of an Ideal Human-Machine Interface for NOTES Mechatronic Support Systems From the View of Surgeons, Gastroenterologists, and Medical Engineers

PURPOSE

To investigate why natural orifice translumenal endoscopic surgery (NOTES) has not yet become widely accepted and to prove whether the main reason is still the lack of appropriate platforms due to the deficiency of applicable interfaces.

METHODS

To assess expectations of a suitable interface design, we performed a survey on human-machine interfaces for NOTES mechatronic support systems among surgeons, gastroenterologists, and medical engineers. Of 120 distributed questionnaires, each consisting of 14 distinct questions, 100 (83%) were eligible for analysis.

RESULTS

A mechatronic platform for NOTES was considered "important" by 71% of surgeons, 83% of gastroenterologist,s and 56% of medical engineers. "Intuitivity" and "simple to use" were the most favored aspects (33% to 51%). Haptic feedback was considered "important" by 70% of participants. In all, 53% of surgeons, 50% of gastroenterologists, and 33% of medical engineers already had experience with NOTES platforms or other surgical robots; however, current interfaces only met expectations in just more than 50%. Whereas surgeons did not favor a certain working posture, gastroenterologists and medical engineers preferred a sitting position. Three-dimensional visualization was generally considered "nice to have" (67% to 72%); however, for 26% of surgeons, 17% of gastroenterologists, and 7% of medical engineers it did not matter (P = 0.018).

CONCLUSION

Requests and expectations of human-machine interfaces for NOTES seem to be generally similar for surgeons, gastroenterologist, and medical engineers. Consensus exists on the importance of developing interfaces that should be both intuitive and simple to use, are similar to preexisting familiar instruments, and exceed current available systems.

Design of a test system for the development of advanced video chips and software algorithms

BACKGROUND

Visual deterioration is a crucial point in minimally invasive surgery impeding surgical performance. Modern image processing technologies appear to be promising approaches for further image optimization by digital elimination of disturbing particles. To make them mature for clinical application, an experimental test environment for evaluation of possible image interferences would be most helpful.

METHODS

After a comprehensive review of the literature (MEDLINE, IEEE, Google Scholar), a test bed for generation of artificial surgical smoke and mist was evolved. Smoke was generated by a fog machine and mist produced by a nebulizer. The size of resulting droplets was measured microscopically and compared with biological smoke (electrocautery) and mist (ultrasound dissection) emerging during minimally invasive surgical procedures.

RESULTS

The particles resulting from artificial generation are in the range of the size of biological droplets. For surgical smoke, the droplet dimension produced by the fog machine was 4.19 µm compared with 4.65 µm generated by electrocautery during a surgical procedure. The size of artificial mist produced by the nebulizer ranged between 45.38 and 48.04 µm compared with the range between 30.80 and 56.27 µm that was generated during minimally invasive ultrasonic dissection.

CONCLUSION

A suitable test bed for artificial smoke and mist generation was developed revealing almost identical droplet characteristics as produced during minimally invasive surgical procedures. The possibility to generate image interferences comparable to those occurring during laparoscopy (electrocautery and ultrasound dissection) provides a basis for the future development of image processing technologies for clinical applications.

A probe-based electromagnetic navigation system to integrate computed tomography during upper gastrointestinal endoscopy

BACKGROUND AND STUDY AIMS

For preoperative work-up, an examination tool that visualizes separately compiled diagnostics in augmented reality would be desirable. We developed a probe-based electromagnetic navigation system, which can be passed through the working channel of an endoscope, to integrate computed tomography (CT) information during upper gastrointestinal endoscopy.

PATIENTS AND METHODS

The target registration error (TRE) of the system was evaluated experimentally and clinically. A total of 24 study patients with upper gastrointestinal cancer were included in the study. The cancerous lesion was endoscopically located (mean duration 8.4 minutes, range 7.1 - 23.2) and the TRE (coronal, transverse, sagittal layer) was measured by comparing the distance between the navigation probe (at the tip of the endoscope) and the target lesion shown on the corresponding CT cross section.

RESULTS

Experimental evaluations showed an accuracy in line with the system's inherent failure rate, with a median TRE of 2.8 mm (IQR 1.8 - 4.3), 2.2 mm (0.4 - 3.7), and 2.8 mm (1.1 - 5.9) in the coronal, transverse, and sagittal planes, respectively. Clinical evaluation revealed a median TRE of 4.8 mm (1.9 - 10.1), 3.9 mm (0.7 - 7.1), and 4.2 mm (0.9 - 8.9), respectively. No complications occurred during navigated endoscopy.

CONCLUSIONS

The probe-based electromagnetic navigation system revealed high accuracy (TRE < 5 mm), facilitating improved interpretation of endoluminal imaging.

[Further technical and digital development in minimally invasive and conventional surgery]

Technological innovations have initiated a fundamental change in invasive therapeutic approaches which has led to a welcome reduction of surgical trauma but was also associated with a declining role of conventional surgery. Active utilization of future technological developments is decisive to promote new therapeutic strategies and to avoid a further loss of importance of surgery. This includes individualized preoperative therapy planning as well as intraoperative diagnostic work-up and navigation and the use of new functional intelligent implants. The working environment "surgical operating room" has to be refurbished into an integrated cooperating functional system. The impact of new technological developments is particularly obvious in minimally invasive surgery. There is a clear tendency towards further reduction in trauma in the surgical access. The incision will become smaller and the number of ports will be further reduced, with the aim of ultimately having just one port (monoport surgery) or even via natural access routes (scarless surgery). Among others, improved visualization including, e.g. autostereoscopy, digital image processing and intelligent support systems, which are able to assist in a cooperative way, will enable these goals to be achieved.

NOTES in Europe: summary of the working group reports of the 2012 EURO-NOTES meeting

The sixth EURO-NOTES workshop (4 - 6 October 2012, Prague, Czech Republic) focused on enabling intensive scientific dialogue and interaction between surgeons, gastroenterologists, and engineers/industry representatives and discussion of the state of the practice and development of natural orifice transluminal endoscopic surgery (NOTES) in Europe. In accordance with previous meetings, five working groups were formed. In 2012, emphasis was put on specific indications for NOTES and interventional endoscopy. Each group was assigned an important indication related to ongoing research in NOTES and interventional endoscopy: cholecystectomy and appendectomy, therapy of colorectal diseases, therapy of adenocarcinoma and neoplasia in the upper gastrointestinal tract, treating obesity, and new therapeutic approaches for achalasia. This review summarizes consensus statements of the working groups.

Solo-surgical laparoscopic cholecystectomy with a joystick-guided camera device: a case-control study

BACKGROUND

This study aimed to evaluate the implementation of a joystick-controlled camera holder (Soloassist; Actormed, Barbing, Germany) in laparoscopic cholecystectomy as so-called solo-surgery compared with the standard operation.

METHODS

Of the 123 patients included in this study, 63 underwent laparoscopic cholecystectomy using the Soloassist system and were compared with 60 patients who underwent laparoscopic cholecystectomy with human assistance. The two groups did not differ significantly in terms of age, sex, body mass index, or American Society of Anesthesiology classification. The surgeons were divided into those highly experienced and those experienced with the new camera holder. The operation times were measured, including setup and dismantling of the system. The assessment also included complications, postoperative hospital stay, measurement of human resources in terms of personnel/minutes/operation, and subjective evaluation of the camera-guiding device by the surgeons.

RESULTS

The hospital stay and operation-related complications were not enhanced in the Soloassist group. The differences in core operation time (p = 0.008) and total operating time (p = 0.001) significantly favored the human assistant. Whereas the absolute duration of surgery was longer, the relative operating time (in personnel/minutes/operation) was significantly shorter (p < 0.001). In 4.8 % of the cases, the operation could not be performed completely with the camera-holding device. Clinically relevant postoperative complications did not occur. The experience of the surgeons did not differ significantly. The subjective evaluation regarding handling, image quality, effort, and satisfaction demonstrated high acceptance of the Soloassist system.

CONCLUSIONS

The camera-guiding device can be implemented without increased complications. The Soloassist system is safe and can be operated even by colleagues without system experience. All the surgeons rated their satisfaction with the system as very good to excellent. Although the operating times were longer than with the standard camera guidance, the absolute overall staff time was reduced.

Real-time instrument detection in minimally invasive surgery using radiofrequency identification technology

BACKGROUND

A key part of surgical workflow recording is recognition of the instrument in use. We present a radiofrequency identification (RFID)-based approach for real-time tracking of laparoscopic instruments.

METHODS

The system consists of RFID-tagged instruments and an antenna unit positioned on the Mayo stand. For reliability analysis, RFID tracking data were compared with the assessment of the perioperative video data of instrument changes (the reference standard for instrument application detection) in 10 laparoscopic cholecystectomies. When the tagged instrument was on the Mayo stand, it was referred to as "not in use." Once it was handed to the surgeon, it was considered to be "in use." Temporal miscounts (incorrect number of instruments "in use") were analyzed. The surgeons and scrub nurses completed a questionnaire after each operation for individual system evaluation.

RESULTS

A total of 110 distinct instrument applications ("in use" versus "not in use") were eligible for analysis. No RFID tag failure occurred. The RFID detection rates were consistent with the period of effective instrument application. The delay in instrument detection was 4.2 ± 1.7 s. The highest percentage of temporal miscounts occurred during phases with continuous application of coagulation current. Surgeons generally rated the system better than the scrub nurses (P = 0.54).

CONCLUSIONS

The feasibility of RFID-based real-time instrument detection was successfully proved in our study, with reliable detection results during laparoscopic cholecystectomy. Thus, RFID technology has the potential to be a valuable additional tool for surgical workflow recognition that could enable a situation dependent assistance of the surgeon in the future.

EndoResect study: endoscopic full-thickness resection of gastric subepithelial tumors

BACKGROUND AND STUDY AIMS

Endoscopic resection of gastric subepithelial tumors (SETs) carries a high risk of perforation. New techniques such as use of the over-the-scope clip (OTSC) may enable secure endoscopic closure of perforations. We aimed to evaluate the feasibility of endoscopic resection of small gastric SETs using a grasp-and-snare technique followed by OTSC closure of the gastric wall if necessary.

PATIENTS AND METHODS

In this prospective study 20 consecutive patients who presented with gastric SETs ≤ 3 cm were enrolled. Endoscopic resection was performed using a double-channel endoscope, a tissue anchor and a monofilament snare. If perforation occurred, the aim was to achieve complete closure with a tissue twin grasper and the OTSC. Procedures were performed under laparoscopic control using a 5-mm optic, which was introduced via a single 5-mm trocar through the umbilicus. All patients were followed up for 3 months after the procedure.

RESULTS

In 6 /20 patients a pure endoscopic approach was impossible and a switch to laparoscopic wedge resection was necessary (large tumor size in 2 /6 patients; mainly extraluminal growth in 4 /6 patients). Solely endoscopic resection was successfully performed in the remaining 14 patients. Amongst these, laparoscopic control was impossible in two cases. Perforation occurred in 6 /14 patients but gastric closure with the OTSC was performed successfully in all these cases. No complications occurred and follow-up was unremarkable.

CONCLUSION

Endoscopic snare resection enables safe treatment of small gastric SETs (diameter ≤ 3 cm) and seems faster and easier to perform than other endoscopic resection techniques, such as endoscopic submucosal dissection (ESD) or submucosal tunneling. Perforations occurring after full-thickness resection can be adequately managed by OTSC closure. Solely endoscopic resection without laparoscopic control seems possible in selected patients with tumors known to have purely intraluminal growth.

Endoscopic horizon stabilization in natural orifice translumenal endoscopic surgery: a randomized controlled trial

BACKGROUND

Spatial orientation in natural orifice translumenal endoscopic surgery (NOTES) has been identified as a potential barrier to clinical application. We aim to evaluate a triaxial inertial sensor and software that automatically corrects any movements on the roll axis of the flexible endoscope, allowing for stabilization of the image horizon during NOTES operations in a randomized controlled trial.

METHODS

A total of 18 participants (11 surgeons/7 gastroenterologists) performed a transgastric task in the ELITE simulator, which included navigation to the appendix and gallbladder, diathermy of the appendix base and gallbladder fossa, and clipping of the cystic duct using a single-channel gastroscope. Each participant performed the task twice with randomization to horizon stabilization occurring at the second attempt. The primary end point was change in overall performance (time taken and errors made) between the first and second attempt, and secondary end points were absolute performances in the second attempt and subjective evaluation.

RESULTS

Without horizon stabilization, there was a median improvement of 42.4% in time taken and 38% in number of errors made from the first to the second attempt; however, with the software turned on, there was a statistically significant deterioration of 4.9% (P = .038) in time taken and an increase in errors made of 183% (P = ns).

CONCLUSIONS

Although the software corrects the view to that preferred during surgery, the endoscopic control mechanism as well as the exit point of the instrument are altered in this process, leading to a deterioration of overall performance. Potential solutions include deploying intermittent horizon stabilization or using a robotic interface to achieve fully aligned perceptual-motor control.