Advanced endoscopic technologies

A Precessing-Coin-like Rotary Actuator for Distal Endoscope Scanners: Proof-of-Concept Study

This paper presents, for the first time, a rotary actuator functionalized by an inclined disc rotor that serves as a distal optical scanner for endoscopic probes, enabling side-viewing endoscopy in luminal organs using different imaging/analytic modalities such as optical coherence tomography and Raman spectroscopy. This scanner uses a magnetic rotor designed to have a mirror surface on its backside, being electromagnetically driven to roll around the cone-shaped hollow base to create a motion just like a precessing coin. An optical probing beam directed from the probe's optic fiber is passed through the hollow cone to be incident and bent on the back mirror of the rotating inclined rotor, circulating the probing beam around the scanner for full 360° sideway imaging. This new scanner architecture removes the need for a separate prism mirror and holding mechanics to drastically simplify the scanner design and thus, potentially enhancing device miniaturization and reliability. The first proof-of-concept is developed using 3D printing and experimentally analyzed to reveal the ability of both angular stepping at 45° and high-speed rotation up to 1500 rpm within the biologically safe temperature range, a key function for multimodal imaging. Preliminary optical testing demonstrates continuous circumferential scanning of the laser beam with no blind spot caused by power leads to the actuator. The results indicate the fundamental feasibility of the developed actuator as an endoscopic distal scanner, a significant step to further development toward advancing optical endoscope technology.

Frontiers in Endoscopic Treatment for Gastroesophageal Reflux Disease

BACKGROUND

The 3rd edition of the evidence-based clinical practice guidelines for gastroesophageal reflux disease (GERD) 2021 from the Japanese Society of Gastroenterology states that the treatment strategy for potassium-competitive acid blocker (PCAB)-refractory GERD remains unclear. Furthermore, even if GERD improves with the administration of an acid secretion inhibitor, it is feared that GERD may flare up after discontinuation of the drug, resulting in some cases in which patients are forced to take vonoprazan semipermanently (the so-called PCAB-dependent cases). From a global perspective, PCAB is not yet used in all countries and regions, and measures that can be taken now for cases in which a conventional proton pump inhibitor (PPI) is inadequately effective need to be devised.

SUMMARY

Endoscopic treatment for GERD may be effective in cases where conventional proton pump inhibitors are ineffective; however, there are insufficient long-term studies to corroborate this, and its cost effectiveness is unknown. Other treatment options for PCAB or PPI-refractory GERD include surgical procedures (Nissen and Toupet operations), which have a longer history than endoscopic treatment for GERD. However, their long-term results are not as good as those of acid secretion inhibitors, and they are not cost effective. Endoscopic treatment for GERD may fill gaps in inadequate surgical treatment. In April 2022, endoscopic anti-reflux mucosal resections (ARMS [anti-reflux mucosectomy] and ESD-G [endoscopic submucosal dissection for GERD]) were approved for reimbursement, making endoscopic treatment of GERD possible throughout Japan.

KEY MESSAGES

It is important to identify the background factors in cases in which endoscopic treatments are effective.

Recent developments in wireless capsule endoscopy imaging: Compression and summarization techniques

Wireless capsule endoscopy (WCE) can be viewed as an innovative technology introduced in the medical domain to directly visualize the digestive system using a battery-powered electronic capsule. It is considered a desirable substitute for conventional digestive tract diagnostic methods for a comfortable and painless inspection. Despite many benefits, WCE results in poor video quality due to low frame resolution and diagnostic accuracy. Many research groups have presented diversified, low-complexity compression techniques to economize battery power consumed in the radio-frequency transmission of the captured video, which allows for capturing the images at high resolution. Many vision-based computational methods have been developed to improve the diagnostic yield. These methods include approaches for automatically detecting abnormalities and reducing the amount of time needed for video analysis. Though various research works have been put forth in the WCE imaging field, there is still a wide gap between the existing techniques and the current needs. Hence, this article systematically reviews recent WCE video compression and summarization techniques. The review's objectives are as follows: First, to provide the details of the requirement, challenges and design percepts for the low complexity WCE video compressor. Second, to discuss the most recent compression methods, emphasizing simple distributed video coding methods. Next, to review the most recent summarization techniques and the significance of using deep neural networks. Further, this review aims to provide a quantitative analysis of the state-of-the-art methods along with their advantages and drawbacks. At last, to discuss existing problems and possible future directions for building a robust WCE imaging framework.

Minimally invasive endoscopic repair of rectovaginal fistula

BACKGROUND

Surgical techniques for repair of rectovaginal fistula (RVF) have been continually developed, but the ideal procedure remains unclear. Endoscopic repair is a novel and minimally invasive technique for RVF repair with increasing reporting.

AIM

To review the current applications and preliminary outcomes of this technique for RVF repair, aiming to give surgeons an alternative in clinical practice.

METHODS

Available articles were searched according to the search strategy. And the sample size, fistula etiology, fistula type, endoscopic repair approaches, operative time and hospital stay, follow-up period, complication and life quality assessment were selected for recording and further analysis.

RESULTS

A total of 11 articles were eventually identified, involving 71 patients with RVFs who had undergone endoscopic repair. The principal causes of RVFs were surgery (n = 51, 71.8%), followed by obstetrics (n = 7, 9.8%), inflammatory bowel disease (n = 5, 7.0%), congenital (n = 3, 4.2%), trauma (n = 2, 2.8%), radiation (n = 1, 1.4%), and in two patients, the cause was unclear. Most fistulas were in a mid or low position. Several endoscopic repair methods were included, namely transanal endoscopic microsurgery, endoscopic clipping, and endoscopic stenting. Most patients underwent > 1-year follow-up, and the success rate was 40%-93%, and all cases reported successful closure. Few complications were mentioned, while postoperative quality of life assessment was only mentioned in one study.

CONCLUSION

In conclusion, endoscopic repair of RVF is novel, minimally invasive and promising with acceptable preliminary effectiveness. Given its unique advantages, endoscopic repair can be an alternative technique for surgeons.

Intraoperative Endoscopy as an Adjuvant to Minimally Invasive Surgery in Pediatrics

Background: Minimally invasive surgery has a different visual and tactile perception compared with conventional surgery, which could lead to complications, especially in complex procedures. In these cases, flexible endoscopy can facilitate and prevent complications in minimally invasive procedures in children. The study aimed to clarify the utility of intraoperative endoscopy as an adjuvant to minimally invasive surgery in children. Materials and Methods: This retrospective study reviewed the medical records of pediatric patients who had undergone endoscopy during a minimally invasive surgery to treat an upper digestive pathology between January 2000 and December 2020. Results: The study included 83 patients who underwent a laparoscopic procedure with simultaneous endoscopy. The diagnosis was peptic stenosis in 9 patients, achalasia in 23, congenital embryonic tracheobronchial remnants in 4, re-fundoplication in 42, esophageal duplication in 2, superior mesenteric artery syndrome in 2, and giant gastric hemangioma in 1 patient. With adjuvant endoscopy, 7 digestive perforations were noted, 11 cases of short esophagus were diagnosed, and the permeability of the anastomosis was confirmed in 6 cases. No complications were related with the endoscopy procedures. Discussion: Minimally invasive surgery has a few special and tactile limitations that can lead to complications in certain procedures. Simultaneous digestive endoscopy in the upper gastrointestinal tract facilitates organ identification and dissection. Conclusion: Digestive endoscopy is an excellent adjunct to minimally invasive surgery in children because it facilitates and identifies complications and ensures safer minimally invasive surgeries. Future prospective studies are required to assess this conclusion.

Intraocular endoscopy: A review

Optimal visualization is one of the most challenging aspects of performing vitreoretinal surgery. In situations where conventional microscopic techniques provide poor posterior visualization, the adjunctive skill set of endoscopic visualization may be needed. This allows for by-passing the opaque anterior segment media and getting access to the posterior segment pathology. Endoscopic vitrectomy is a useful and unique adjunct to microincision vitreoretinal surgery. The optical set-up of endoscopy allows for clinical approaches that are impossible with regular microscope viewing systems. These include the ability to observe across optically significant anterior segment opacities and directly visualize the posterior segment of the eye. It also allows for visualizing the difficult-to-access retroirideal, retrolental, and anterior retinal structures. Surgical access to anatomic spaces like the pars plana, pars plicata, ciliary sulcus, ciliary body, and peripheral lens is tedious. This is made simpler by endoscopy. In this review, we summarize and review the usage of the intraocular endoscope as a diagnostic and therapeutic armamentarium across a wide spectrum of ocular pathologies.

easyEndo robotic endoscopy system: Development and usability test in a randomized controlled trial with novices and physicians

BACKGROUND

Some difficulties are common when using endoscopes. Steering is not intuitive, the endoscope weight is a physical burden to physicians and communication problems often occur between operators.

METHOD

To overcome these, we developed a robotic endoscopy system and conducted a usability test to compare conventional and robotic manipulation. Nine novices and eighteen physicians participated with the physicians being divided into intermediate and expert groups. The participants performed endoscope insertion into a simulator (physicians) or lesion marking on a testbed (novices) and simulate biopsies.

RESULT

Novices completed the tasks faster and with a lower workload when using robotic manipulation, whereas the experts showed the opposite trend. Still, the intermediates showed no significant difference as trials proceeded. Nevertheless, the learning curve analysis showed that the learning rate in all groups is greater for robotic manipulation (21.02% on average) than for conventional manipulation (13.75%) and predicted that physicians can reach manual performance.

CONCLUSION

The proposed robotic endoscopy system may allow solo-manipulation using one controller and may be more intuitive and convenient to use than conventional manipulation.

The evolution of TIF: transoral incisionless fundoplication

Transoral incisionless fundoplication (TIF) was introduced in 2006 as a concerted effort to produce a natural orifice procedure for reflux. Since that time, the device, as well as the procedure technique, has evolved. Significant research has been published during each stage of the evolution, and this has led to considerable confusion and a co-mingling of outcomes, which obscures the results of the current device and procedure. This report is intended to review the identified stages and literature associated with each stage to date and to review the current state of treatment outcomes.

Endoscopic vitreoretinal surgery: principles, applications and new directions

Purpose

To analyze endoscopic vitreoretinal surgery principles, applications, challenges and potential technological advances.

Background

Microendoscopic imaging permits vitreoretinal surgery for tissues that are not visible using operating microscopy ophthalmoscopy. Evolving instrumentation may overcome some limitations of current endoscopic technology.

Analysis

Transfer of the fine detail in endoscopic vitreoretinal images to extraocular video cameras is constrained currently by the caliber limitations of intraocular probes in ophthalmic surgery. Gradient index and Hopkins rod lenses provide high resolution ophthalmoscopy but restrict surgical manipulation. Fiberoptic coherent image guides offer surgical maneuverability but reduce imaging resolution. Coaxial endoscopic illumination can highlight delicate vitreoretinal structures difficult to image in chandelier or endoilluminator diffuse, side-scattered lighting. Microendoscopy’s ultra-high magnification video monitor images can reveal microscopic tissue details blurred partly by ocular media aberrations in contemporary surgical microscope ophthalmoscopy, thereby providing a lower resolution, invasive alternative to confocal fundus imaging. Endoscopic surgery is particularly useful when ocular media opacities or small pupils restrict or prevent transpupillary ophthalmoscopy. It has a growing spectrum of surgical uses that include the management of proliferative vitreoretinopathy and epiretinal membranes as well as the implantation of posterior chamber intraocular lenses and electrode arrays for intraretinal stimulation in retinitis pigmentosa. Microendoscopy’s range of applications will continue to grow with technological developments that include video microchip sensors, stereoscopic visualization, chromovitrectomy, digital image enhancement and operating room heads-up displays.

Conclusion

Microendoscopy is a robust platform for vitreoretinal surgery. Continuing clinical and technological innovation will help integrate it into the modern ophthalmic operating room of interconnected surgical microscopy, microendoscopy, vitrectomy machine and heads-up display instrumentation.

Are Current Advances of Compression Algorithms for Capsule Endoscopy Enough? A Technical Review

The recent technological advances in capsule endoscopy system have revolutionized the healthcare system by introducing new techniques and functionalities to diagnose gastrointestinal tract. These techniques improve diagnostic accuracy and reduce the risk of hospitalization. Although many benefits of capsule endoscopy are known, there are still limitations including lower battery life, higher bandwidth, poor image quality and lower frame rate, which have restricted its wide use. In order to solve these limitations, the importance of a low-cost compression algorithm, that produces higher frame rate with better image quality and yet consumes lower bandwidth and transmission power, is paramount. While several review papers have been published describing the capability of capsule endoscope in terms of its functionality and emerging features, an extensive review on the compression algorithms from past and for future applications is still of great interest. Hence, in this review, we aim to address the issue by exploring the characteristics of endoscopic images, analyzing the strengths and weaknesses of useful compression techniques, and making suggestions for possible future adaptation.

Feasibility of joystick guided colonoscopy

The flexible endoscope is increasingly used to perform minimal invasive interventions. A novel add-on platform allows single-person control of both endoscope and instrument at the site of intervention. The setup changes the current routine of handling the endoscope. This study aims to determine if the platform allows effective and efficient manipulation to position the endoscope at potential intervention sites throughout the bowel. Five experts in flexible endoscopy first performed three colonoscopies on a computer simulator using the conventional angulation wheels. Next they trained with the joystick interface to achieve their personal level of intubation time with low pain score. 14 PhD students (novices) without hands-on experience performed the same colonoscopy case using either the conventional angulation wheels or joystick interface. Both novice groups trained to gain the average expert level. The cecal intubation time, pain score and visualization performance (% of bowel wall) were recorded. All experts reached their personal intubation time in 6 ± 6 sessions. Three experts completed their learning curve with low pain score in 8 ± 6 sessions. The novices required 11 ± 6 sessions using conventional angulation wheels, and 12 ± 6 sessions using the joystick interface. There was no difference in the visualization performance between the novice and between the expert groups. This study shows that the add-on platform enables endoscope manipulation required to perform colonoscopy. Experts need only a relatively short training period. Novices are as effective and as efficient in endoscope manipulation when comparing the add-on platform with conventional endoscope control.

Transoral incisionless fundoplication for the treatment of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a common and costly chronic medical condition affecting millions of patients. It is associated with substantial morbidity and negatively impacts quality of life. Reflux of gastric contents into the esophagus damages the esophageal mucosa and is associated with conditions including esophagitis and esophageal stricture. While GERD is most commonly seen in Western populations, changes in dietary patterns and the global increase in obesity have led to a pronounced increase in its prevalence worldwide. Medical and surgical GERD therapies are costly and pose considerable side effects, leading many to pursue effective endoscopic treatment options. Transoral incisionless fundoplication is an endoluminal procedure that offers patients a minimally invasive treatment option with the potential to eliminate the need for medical acid suppression with a low risk of side effects.

Diagnosis and management of choledocholithiasis in the golden age of imaging, endoscopy and laparoscopy

Biliary lithiasis is an endemic condition in both Western and Eastern countries, in some studies affecting 20% of the general population. In up to 20% of cases, gallbladder stones are associated with common bile duct stones (CBDS), which are asymptomatic in up to one half of cases. Despite the wide variety of examinations and techniques available nowadays, two main open issues remain without a clear answer: how to cost-effectively diagnose CBDS and, when they are finally found, how to deal with them. CBDS diagnosis and management has radically changed over the last 30 years, following the dramatic diffusion of imaging, including endoscopic ultrasound (EUS) and magnetic resonance cholangiography (MRC), endoscopy and laparoscopy. Since accuracy, invasiveness, potential therapeutic use and cost-effectiveness of imaging techniques used to identify CBDS increase together in a parallel way, the concept of "risk of carrying CBDS" has become pivotal to identifying the most appropriate management of a specific patient in order to avoid the risk of "under-studying" by poor diagnostic work up or "over-studying" by excessively invasive examinations. The risk of carrying CBDS is deduced by symptoms, liver/pancreas serology and ultrasound. "Low risk" patients do not require further examination before laparoscopic cholecystectomy. Two main "philosophical approaches" face each other for patients with an "intermediate to high risk" of carrying CBDS: on one hand, the "laparoscopy-first" approach, which mainly relies on intraoperative cholangiography for diagnosis and laparoscopic common bile duct exploration for treatment, and, on the other hand, the "endoscopy-first" attitude, variously referring to MRC, EUS and/or endoscopic retrograde cholangiography for diagnosis and endoscopic sphincterotomy for management. Concerning CBDS diagnosis, intraoperative cholangiography, EUS and MRC are reported to have similar results. Regarding management, the recent literature seems to show better short and long term outcome of surgery in terms of retained stones and need for further procedures. Nevertheless, open surgery is invasive, whereas the laparoscopic common bile duct clearance is time consuming, technically demanding and involves dedicated instruments. Thus, although no consensus has been achieved and CBDS management seems more conditioned by the availability of instrumentation, personnel and skills than cost-effectiveness, endoscopic treatment is largely preferred worldwide.

Minimally invasive surgical instruments with an accessory channel capable of integrating fibre-optic cable for optical biopsy: A review of the state of the art

This review article provides a comprehensive overview and classification of minimally invasive surgical instruments with an accessory channel incorporating fibreoptics or another auxiliary device for various purposes. More specifically, this review was performed with the focus on the newly emerging field of optical biopsy, its objective being to discuss primarily the instruments capable of carrying out the optical biopsy and subsequent tissue resection. Instruments housing the fibreoptics for other uses, as well as instruments with an accessory channel capable of housing the fibreoptics instead of their original auxiliary device after relevant design modifications, supplement the review. The entire Espacenet and Scopus databases were searched, yielding numerous patents and articles on conceptual and existing instruments satisfying the criteria. The instruments were categorised based on the function the fibreoptics or the auxiliary device serves. On the basis of their geometrical placement with respect to the tissue resector or manipulator, the subcategories were further defined. This subdivision was used to identify the feasibility of performing the optical biopsy and the tissue resection in an accurate and successive fashion. In general, the existing concepts or instruments are regarded as limited with regard to such a functionality, either due to the placement of their accessory channel with or without the fibreoptics or due to the operational restrictions of their tissue manipulators. A novel opto-mechanical biopsy harvester, currently under development at Delft University of Technology, is suggested as a promising alternative, ensuring a fast and accurate succession of the optical and the mechanical biopsies of a flat superficial tissue.

Advances in minimally invasive surgery in pediatric patients

Surgery has changed dramatically over the last several decades. The emergence of MIS has allowed pediatric surgeons to manage critically ill neonates, children, and adolescents with improved outcomes in pain, postoperative course, cosmesis, and return to normal activity. Procedures that were once thought to be too difficult to attempt or even contraindicated in pediatric patients in many instances are now the standard of care. New and emerging techniques, such as single-incision laparoscopy, endoscopy-assisted surgery, robotic surgery, and techniques yet to be developed, all hold and reveal the potential for even further advancement in the management of these patients. The future of MIS in pediatrics is exciting; as long as our primary focus remains centered on developing techniques that limit morbidity and maximize positive outcomes for young patients and their families, the possibilities are both promising and infinite.

Robotics in Colonoscopy

Colorectal cancer is the second leading cause of mortality in men and women in the United States. While there is a definite advantage regarding the use of colonoscopies in screening, there is still a lack of widespread acceptance of colonoscopy use in the general public. This is evident by the fact that up to 75% of patients diagnosed with colorectal cancer present with locally advanced disease. In order to make colonoscopy and in turn colorectal cancer screening a patient friendly and a comfortable test some changes in tool are necessary. The conventional colonoscope has not changed much since its development. There are several new advances in colorectal screening practices. One of the most promising new advances is the advent of robotic endoscopic techniques.

Intuitive user interfaces increase efficiency in endoscope tip control

BACKGROUND

Flexible endoscopes are increasingly used to perform advanced intraluminal and transluminal interventions. These complex interventions demand accurate and efficient control, however, current endoscopes lack intuitiveness and ergonomic control of the endoscope tip. Alternative handheld controllers can improve intuitiveness and ergonomics, though previous studies are inconclusive concerning their effect on the efficiency of endoscope manipulation. The aim of this study is to determine the efficiency of a robotic system with intuitive user interface in controlling the tip of the flexible endoscope.

METHODS

We compared the efficiency of time and tip trajectory when steering the endoscope tip using the conventional steering wheels and a robotic platform with three different user interfaces: a touchpad in combination with a position control algorithm, a joystick combined with linear rate control, and a joystick combined with non-linear rate control. Fourteen participants, without a medical background, used all four interfaces. They performed both large navigational and fine targeting tasks in a simulated environment which allowed objective cross-subject comparison. Afterward, the participants were asked to select their preferred steering method.

RESULTS

Participants were significantly faster in steering the endoscope tip when using robotic steering compared to using the conventional steering method. Between the robotic interfaces, using the touchpad was significantly faster compared to the joystick with linear rate control. Use of the joystick with non-linear rate control led to a shorter tip trajectory compared to the touchpad. The majority of participants preferred the joystick with non-linear rate control over the other steering methods.

CONCLUSIONS

This work shows that intuitive user interfaces can improve the efficiency of endoscope tip steering.

Natural-orifice translumenal endoscopic surgery (NOTES): minimally invasive evolution or revolution?

Since the first animal experimental laparoscopy in 1902, minimal access techniques have revolutionized surgery. Using the natural orifice dates back to at least the second century when Soranus performed a vaginal hysterectomy. The main difference between traditional endolumenal surgery and the translumenal approach of natural-orifice translumenal endoscopic surgery (NOTES) is the intentional puncture of a healthy organ in NOTES to access a cavity or other organ. The aim of this review was to examine the past, present, and potential future role of NOTES in the context of other developments in minimal access surgery. NOTES is at an early stage in its development and a convincing benefit over laparoscopy has not been demonstrated. Concerns regarding complications, for example of viscerotomy closure, have limited the widespread uptake of pure NOTES. However, it is likely that technological advances for NOTES surgery will enhance conventional laparoscopic and endoscopic techniques.

Experience with endoscopy and endoscopy-assisted management of pediatric surgical problems: results and lessons

Minimally invasive surgical techniques are becoming increasingly popular within the pediatric population. Flexible endoscopy may enhance or replace existing techniques in the future. Many of the reported benefits of laparoscopy and thoracoscopy may apply to endoscopy and endoscopy-assisted procedures; however, no reports exist as to the application, results, and outcomes for these procedures in children. It was hypothesized that endoscopy is a useful and safe adjunct for pediatric surgical patients. Retrospective review of medical records for patients who underwent endoscopy or endoscopy-assisted operations at two children's hospitals over 3 years (August 31, 2007-August 31, 2010) was completed. During this time period, 30 procedures were performed on 28 patients. Indications for procedure, age, operative technique, operative times, surgical outcomes, complications, and length of stay for each patient were reviewed. Patient age ranged from 3 days to 20 years. Indications for operation included esophageal pathology (13), gastroduodenal pathology (14), pancreatic pseudocyst (2), and displaced sigmoid Chait® (Cook, Inc., Bloomington, IN, USA) tube. Although endoscopy was intended only as an adjunct in all cases, the planned procedure was satisfactorily completed with a purely endoscopic approach in six cases. There were no intraoperative complications, and minor postoperative complications including one stricture requiring dilation, postoperative stridor, and esophageal leak, were each successfully managed conservatively. Endoscopy offers a promising adjunct to more traditional minimally invasive techniques in children. In some cases, endoscopy may offer an alternative to more invasive procedures or eliminate the need for tube thoracostomy or post-procedural contrast studies in some esophageal cases.

Capsule endoscopy: from current achievements to open challenges

Wireless capsule endoscopy (WCE) can be considered an example of disruptive technology since it represents an appealing alternative to traditional diagnostic techniques. This technology enables inspection of the digestive system without discomfort or need for sedation, thus preventing the risks of conventional endoscopy, and has the potential of encouraging patients to undergo gastrointestinal (GI) tract examinations. However, currently available clinical products are passive devices whose locomotion is driven by natural peristalsis, with the drawback of failing to capture the images of important GI tract regions, since the doctor is unable to control the capsule's motion and orientation. To address these limitations, many research groups are working to develop active locomotion devices that allow capsule endoscopy to be performed in a totally controlled manner. This would enable the doctor to steer the capsule towards interesting pathological areas and to accomplish medical tasks. This review presents a research update on WCE and describes the state of the art of the basic modules of current swallowable devices, together with a perspective on WCE potential for screening, diagnostic, and therapeutic endoscopic procedures.

Endoscopic full-thickness resection of submucosal gastric tumors

BACKGROUND AND AIMS

Endoscopic full-thickness resection (EFTR) is a minimally invasive method for en bloc resection of gastrointestinal lesions, such as early cancer or submucosal tumor. The aim of this pilot study was to evaluate a novel EFTR prototype device for full-thickness resection of the gastric wall containing artificial submucosal lesions.

METHODS

Six artificial submucosal tumors were surgically created in the gastric submucosa by implanting 8-mm cork beads in anesthetized pigs. EFTR of the lesions was attempted using a prototype device which consists of a large transparent plastic cap, loaded onto the tip of the endoscope, into which the submucosal lesion and the surrounding gastrointestinal wall can be pulled by using suction, a grasping forceps, or a dedicated anchoring device. An over-the-scope clip (OTSC) can be deployed underneath the submucosal lesion and a pre-loaded snare is used for EFTR above the OTSC.

RESULTS

The median procedure time was 15 min (interquartile range 11-22). Successful resection of the artificial submucosal lesion was achieved in 4/6 (67%) cases. Successful EFTR of the gastric wall was achieved in 3/6 (50%) cases. In all cases, the OTSC closed the EFTR site completely.

CONCLUSIONS

Gastric EFTR using the novel EFTR prototype device is feasible in a live animal model. The technique can achieve a full-thickness gastric wall and submucosal tumor resection with reliable closure of the gastric wall, but further refinements of the technique and device are necessary in order to reliably resect submucosal lesions, especially larger ones.

Long-Term Results of Radiofrequency Energy Delivery for the Treatment of GERD: Results of a Prospective 48-Month Study

Since 2000, radiofrequency (RF) energy treatment has been increasingly offered as an alternative option to invasive surgical procedures for selected patients with gastroesophageal reflux disease (GERD). Out of 69 patients treated since June 2002 to December 2007 with the Stretta procedure, 56 of them reached by the end of 2010 a 48-month followup. RF treatment significantly improved heartburn scores, GERD-specific quality of life scores, and general quality of life scores at 24 and 48 months in 52 out of 56 patients (92,8%). At each control time both mean heartburn and GERD HRQL scores decreased (P = 0.001 and P = 0.003, resp.) and both mental SF-36 and physical SF-36 ameliorated (P = 0.001 and 0.05, resp.). At 48 months, 41 out of 56 patients (72,3%) were completely off PPIs. Morbidity was minimal, with only one relevant but transient complication. According to other literature data, this study shows that RF delivery to LES is safe and durably improves symptoms and quality of life in well-selected GERD patients.

Clinical and pH-metric outcomes of transoral esophagogastric fundoplication for the treatment of gastroesophageal reflux disease

BACKGROUND

Transoral treatment of gastroesophageal reflux disease (GERD) using the EsophyX device enables creation of an esophagogastric fundoplication with potential for better control of reflux than gastrogastric techniques. Efficacy and safety of a rotational/longitudinal esophagogastric transoral incisionless fundoplication (TIF) was evaluated retrospectively using subjective and objective outcomes.

METHODS

Thirty-seven consecutive patients on antisecretory medication and with proven gastroesophageal reflux and limited hiatal hernia underwent TIF for persistent GERD symptoms. Five patients were reoperations for failed laparoscopic fundoplication.

RESULTS

Of the 37 treated patients, 57% were female. The median age was 58 (range=20-81) years and BMI was 25.5 (range=15.9-36.1) kg/m2. Sixty-eight percent indicated GERD-associated cough, asthma, or aspiration as a primary complaint and 32% complained of heartburn or regurgitation. The TIF procedures created tight wraps of 230°-330° extending 3-4 cm above the Z-line. Two complications occurred: one mediastinal abscess treated laparoscopically and one postoperative bleeding requiring transfusion. At 6 (range=3-14) months median follow-up TIF resulted in a significant improvement of both atypical and typical symptoms in 64% and 70-80% of patients, respectively, as indicated by the corresponding GERD health-related quality of life (HRQL) and reflux symptom index (RSI) score reduction by 50% or more compared to baseline on proton pump inhibitors (PPIs). No patient reported problems with dysphagia, bloating, or excess flatulence, and 82% were not taking any PPIs. Reflux characteristics were significantly improved and normalized in 61, 89, and 56% of patients in terms of acid exposure, number of refluxates, and DeMeester scores, respectively. TIF was effective in treating GERD in 75% of patients among whom 54% were in a complete "remission" and 21% were "improved." The remaining 25% were considered failures, and five (13.5%) patients underwent revision.

CONCLUSION

Rotational/longitudinal esophagogastric fundoplication using the EsophyX device significantly improved symptomatic and objective outcomes in over 70% of patients at median 6-month follow-up. Post-fundoplication side effects were not reported after TIF.

Advances in transoral fundoplication for oesophageal reflux

BACKGROUND

The purpose of this review was to evaluate transoral fundoplication devices for gastro-oesophageal reflux disease that have been commercially available within the last 5 years.

METHODS

Literature databases including Medline and Pubmed were searched from January 2005 to November 2010. Both blinded and unblinded randomized studies were evaluated.

RESULTS

We reviewed the literature for evaluations of primary transoral endoluminal fundoplication devices which included EndoCinch, NDO Plicator, Esophyx, and Stretta. Reviews of all studies with greater than 20 patients were evaluated to assess the efficacy and safety of transoral fundoplication devices. These endoluminal devices were primary matched against sham procedures. The EndoCinch and Stretta procedures were the only devices compared to laparoscopic fundoplication, the current standard for surgical management of gastro-oesophageal reflux disease.

CONCLUSION

The field of endoluminal treatment of gastro-oesophageal reflux disease has gained popularity over the last several years. Endoluminal treatment of gastro-oesophageal reflux disease has been shown to be safe and effective in recent studies. We still believe more randomized prospective studies need to be carried out to determine if endoluminal therapies will be a durable option for patients with gastro-oesophageal reflux disease. Continuing research will further the advancement of endoluminal gastro-oesophageal reflux disease procedures in the future.

Rectal laterally spreading tumors successfully treated in two steps by endoscopic submucosal dissection and endoscopic mucosal resection

BACKGROUND

Endoscopic submucosal dissection (ESD) is an advanced technique of therapeutic endoscopy alternative to endoscopic mucosal resection (EMR) for superficial gastrointestinal neoplasms >2 cm. ESD allows for the direct dissection of the submucosa and large lesions can be resected en bloc. ESD is not limited by resection size, increases histologically complete resection rates and may reduce the local recurrence. Nevertheless, the technique is time-consuming, technically demanding and associated with a high complication rate. To reduce the risk of complications, different devices and technical advances have been proposed with conflicting results and, still, ESD en bloc resections of huge lesions are associated with increased complications.

CASE PRESENTATION

We successfully used a combined ESD/EMR technique for huge rectal laterally spreading tumors (LSTs). ESD was used for circumferential resection of 2/3 of the lesion followed by piecemeal resection (2-3 pieces) of the central part of the tumour. In all three patients we obtained the complete dissection of the polyp and the complete histological evaluation in absence of complications and recurrence at 6 months' follow up.

CONCLUSIONS

In the treatment of rectal LSTs, the combined treatment - ESD/EMR resection may be considered a suitable therapeutic option, indicated in selected cases as an alternative to surgery, in which the two techniques are neither reliable nor safe separately. However, to confirm our results, larger trials with longer follow up are required together with improvement of the technique and of the technical devices.

Wireless steering mechanism with magnetic actuation for an endoscopic capsule

This paper illustrates the design, development and testing of a miniature mechanism to be integrated in endoscopic capsules for precise steering capabilities (Magnetic Internal Mechanism, MIM). The mechanism consists of an electromagnetic motor connected to a couple of small permanent magnets and immersed in a static magnetic field produced by an external permanent magnet or a by an electromagnetic coil. The overall steering capsule, integrating the magnetic steering mechanism and the vision system is 15.6 mm in diameter, 48 mm in length, 14.4 g in weight and can be oriented with an accuracy of 0.01 degrees . As regards system scalability, the capsule size could be reduced down to 11 mm in diameter by optimizing some mechanical components. On the other hand, the magnets size cannot be reduced because the magnetic link between internal and external magnets at typical operation distances (about 15 mm) would be weak.

Endoluminal fundoplication (ELF) for GERD using EsophyX: a 12-month follow-up in a single-center experience

BACKGROUND

Several endoscopic antireflux therapies have been proposed to reduce the need for chronic medical therapy or laparoscopic fundoplication for gastroesophageal reflux disease (GERD). Aim of this study was to evaluate the short- and mid-term clinical results of endoluminal fundoplication (ELF) with EsophyX.

PATIENTS AND METHODS

From June 2006 to April 2008, 20 patients were enrolled in the study. All the ELFs were performed under general anesthesia.

RESULTS

The mean duration of the procedure was 63 min (range 38-105). A median of 14 fasteners was placed. There were no major intraoperative complications. Two patients developed early complications and were treated conservatively. Four patients underwent, within the first year post-ELF, a laparoscopic fundoplication because of persistence of symptoms. One patient was lost to follow-up between 6 and 12 months. Among the other 15 patients who completed 12 months follow-up, the GERD health-related quality of life score decreased from a median of 40 to a median of 10 (p < 0.05), and seven patients were still off proton pump inhibitor. An improvement in esophageal acid exposure was recorded in 16.6% of patients, while in 66.7%, it worsened.

CONCLUSIONS

ELF induced improvement of GERD symptoms and patients quality of life in a subgroup of patients with a reduced need for medication. However, it did not significantly change esophageal acid exposure in these patients. The need for revisional standard laparoscopic fundoplication was high.

Robotic magnetic steering and locomotion of capsule endoscope for diagnostic and surgical endoluminal procedures

This paper describes a novel approach to capsular endoscopy that takes advantage of active magnetic locomotion in the gastrointestinal tract guided by an anthropomorphic robotic arm. Simulations were performed to select the design parameters allowing an effective and reliable magnetic link between the robot end-effector (endowed with a permanent magnet) and the capsular device (endowed with small permanent magnets). In order to actively monitor the robotic endoluminal system and to efficiently perform diagnostic and surgical medical procedures, a feedback control based on inertial sensing was also implemented. The proposed platform demonstrated to be a reliable solution to move and steer a capsular device in a slightly insufflated gastrointestinal lumen.

Role of endoscopic ultrasound in pancreatic cancer

Pancreatic cancer (PC) is the fourth most common cause of cancer deaths in Western societies. It is an aggressive tumor with an overall 5-year survival rate of less than 5%. Surgical resection offers the only possibility of cure and long-term survival for patients suffering from PC; however, unfortunately, fewer than 20% of patients suffering from PC have disease that is amendable to surgical resection. Therefore, it is important to accurately diagnose and stage these patients to enable optimal treatment of their disease. The imaging modalities involved in the diagnosis and staging of PC include multidetector CT scanning, endoscopic ultrasound (EUS), endoscopic retrograde cholangiopancreaticography and MRI. The roles and relative importance of these imaging modalities have changed over the last few decades and continue to change owing to the rapid technological advances in medical imaging, but these investigations continue to be complementary. EUS was first introduced in the mid-1980s in Japan and Germany and has quickly gained acceptance. Its widespread use in the last decade has revolutionized the management of pancreatic disease as it simultaneously provides primary diagnostic and staging information, as well as enabling tissue biopsy. This article discusses the potential benefits and drawbacks of EUS in the primary diagnosis, staging and assessment of resectability, and EUS-guided fine-needle aspiration in PC. Difficult diagnostic scenarios and pitfalls are also discussed. A suggested management algorithm for patients with suspected PC is also presented.

Navigation systems and platforms in natural orifice translumenal endoscopic surgery (NOTES)

INTRODUCTION

The latest evolution in minimally invasive surgery is to avoid skin incisions by using natural orifices, called natural orifice translumenal endoscopic surgery (NOTES). However, to safely and efficiently perform NOTES, the requirements of the operating platform used need to be modified from the conventional endoscope. The aim of this paper is to systematically review specialised operating platforms used or in development for NOTES procedures.

METHODS

A review of the literature was conducted using Ovid EMBASE, Ovid MEDLINE, ISI Current Contents Connect and PubMed, a search tool of the National Library of Medicine and the national institute of Health, until the 1st of December 2008. Data was extracted to specifically characterise the available platforms, their availability, advantageous characteristics and potential disadvantages.

RESULTS

There were 9 studies included in this review describing 6 different navigation platforms and 3 robotic systems for NOTES. Based on this analysis, it is our opinion that although the described surgical systems and navigation platforms possess some attractive characteristics, such as maneuverability, stability, enhanced optics, and the ability to provide triangulation and insufflation with proper suction/irrigation maintenance, there does not appear to be one platform which is clearly superior to others.

CONCLUSION

Current instruments are not suited for effective surgery in a NOTES environment. There are several important requirements for NOTES platform: 1) to provide safe access to the peritoneal cavity; 2) to provide a stable channel for instrumentation passageway and safe navigation, 3) to provide good visualization and illumination, thereby decreasing disorientation, 4) to maintain proper insufflation and suction/irrigation, and 5) to provide maneuverability and triangulation of the instruments. Effective collaborations between clinicians, engineering departments and industry are essential to maximise and expedite the innovative process in producing an optimal NOTES platform.

Natural orifice translumenal surgery: from scales to symphonies

PURPOSE OF REVIEW

Natural orifice transluminal endoscopic surgery is a new therapeutic procedure that combines surgical and endoscopic skills. Although not currently widely used, it is gaining momentum both in the animal laboratory and in human case reports.

RECENT FINDINGS

To date, 15 procedures have been successfully performed on humans worldwide. These included appendectomies (eight), liver biopsies (three), tubal ligation (one), and cholecystectomies (three). Numerous other procedures, using hybrid techniques that combine natural orifice transluminal endoscopic surgery technology with alternative conventional laparoscopic techniques, have been described in human clinical trials. In this review, we will discuss the potential benefits of this procedure over conventional surgical interventions, briefly review the major challenges to the technique (access, spatial orientation, anastomosis, and closure), and point out the technological limitations that severely handicap its potential.

SUMMARY

Despite the widespread interest in this technology, there are a lot of shortcomings: limitations in equipment, lack of clinical outcome data, and absence of randomized trials that compare it with alternative conventional surgical interventions. Nevertheless, it is crucial to remember that we have just started the evaluation process for this new exiting technology, and that, clearly, the best is yet to come.