Carla Rolanda

Transvesical thoracoscopy: A natural orifice translumenal endoscopic approach for thoracic surgery

BackgroundRecently there has been an increasing enthusiasm for using natural orifices translumenal endoscopic surgery (NOTES) to perform scarless abdominal procedures. We have previously reported the feasibility and safety of the transvesical endoscopic peritoneoscopy in a long-term survival porcine model as useful for those purposes. Herein, we report our successful experience performing transvesical and transdiaphragmatic endoscopic approach to the thoracic cavity in a long-term survival study in a porcine model.MethodsTransvesical and transdiaphragmatic endoscopic thoracoscopy was performed in six anesthetized female pigs. A 5 mm transvesical port was created on the bladder wall and an ureteroscope was advanced into the peritoneal cavity. After diaphragm inspection, we introduced through the left diaphragmatic dome a ureteroscope into the left thoracic cavity. In all animals, we performed thoracoscopy as well as peripheral lung biopsy. Animals were sacrificed by day 15 postoperatively.ResultsWe easily introduced a 9.8 Fr ureteroscope into the thoracic cavity that allowed us to visualize the pleural cavity and to perform simple surgical procedures such as lung biopsies without complications. There were neither respiratory distress episodes nor surgical complications to report. Postmortem examination revealed complete healing of vesical and diaphragmatic holes, whereas no signs of infection or adhesions were observed in the peritoneal or thoracic cavities.ConclusionThis study demonstrates the feasibility of transvesical thoracoscopy in porcine model. However, although this study extends the potential applications of NOTES to the thoracic cavity, new instruments and further work are needed to provide evidence that this could be translated to humans and with advantages for patients.

Endoscopic Closure of Transmural Bladder Wall Perforations

BACKGROUND Traditionally, intraperitoneal bladder perforations caused by trauma or iatrogenic interventions have been treated by open or laparoscopic surgery. Additionally, transvesical access to the peritoneal cavity has been reported to be feasible and useful for natural orifice translumenal endoscopic surgery (NOTES) but would be enhanced by a reliable method of closing the vesicotomy. OBJECTIVE To assess the feasibility and safety of an endoscopic closure method for vesical perforations using a flexible, small-diameter endoscopic suturing kit in a survival porcine model. DESIGN, SETTING, AND PARTICIPANTS This pilot study was performed at the University of Minho, Braga, Portugal, using six anesthetized female pigs. INTERVENTIONS Closure of a full-thickness longitudinal incision in the bladder dome (up to 10 mm in four animals and up to 20 mm in two animals) with the endoscopic suturing kit using one to three absorbable stitches. MEASUREMENTS The acute quality of sealing was immediately tested by distending the bladder with methylene-blue dye under laparoscopic control (in two animals). Without a bladder catheter, the animals were monitored daily for 2 wk, and a necropsy examination was performed to check for the signs of peritonitis, wound dehiscence, and quality of healing. RESULTS AND LIMITATIONS Endoscopic closure of bladder perforation was carried out easily and quickly in all animals. The laparoscopic view revealed no acute leak of methylene-blue dye after distension of the bladder. After recovery from anaesthesia, the pigs began to void normally, and no adverse event occurred. Postmortem examination revealed complete healing of vesical incision with no signs of infection or adhesions in the peritoneal cavity. No limitations have yet been studied clinically. CONCLUSIONS This study demonstrates the feasibility and the safety of endoscopic closure of vesical perforations with an endoscopic suturing kit in a survival porcine model. This study provides support for further studies using endoscopic closure of the bladder which may lead to a new era in management of bladder rupture and adoption of the transvesical port in NOTES procedures.

Increased hepatic expression of TLR2 and TLR4 in the hepatic inflammation-fibrosis-carcinoma sequence:

We evaluated expression of TLR2, TLR4 and proinflammatory genes [NF-κB, TNF-α, cyclooxygenase-2 (COX-2)] in liver samples of patients in different stages of liver disease. Fifteen patients with unexplained transaminases elevation (reference group), 22 with viral chronic hepatitis (hepatitis group), 14 with virus-induced severe fibrosis/cirrhosis (cirrhosis group) and 10 with hepatocarcinoma (hepatocarcinoma group) were consecutively included in the study. Quantification of TLR2, TLR4, NF-κB, TNF-α and COX-2 mRNA was done by real-time RT-PCR and TLR2 and TLR4 protein expression was evaluated by immunohistochemistry. Compared with reference, TLR2 and TLR4 mRNA was increased in hepatitis (TLR2: 2.66 ± 0.69; TLR4: 3.11 ± 0.79; P < 0.05) and cirrhosis (TLR2: 2.14 ± 0.5; TLR4: 1.74 ± 0.27; P < 0.05) and decreased in hepatocarcinoma (TLR2: 0.48 ± 0.15; TLR4: 0.54 ± 0.10; P < 0.05). This associated with increased TNF-α and COX-2 mRNA in hepatitis (TNF-α: 3.24 ± 0.79; COX-2: 2.47 ± 0.36; P < 0.05) and cirrhosis (TNF-α: 1.73 ± 0.28; COX-2: 1.8 ± 0.35, P < 0.05), whereas NF-κB mRNA was increased in hepatitis (2.42 ± 0.31; P < 0.05) and unchanged in cirrhosis (1.34 ± 0.17; P = 0.3). Hepatocarcinoma presented increased COX-2 mRNA (1.63 ± 0.15; P < 0.05) and maintained (at decreased levels) mRNA of NF-κB (0.52 ± 0.12) and TNF-α (0.52 ± 0.12; P < 0.05, all genes). Immunohistochemistry confirmed increased expression of TLR2 and TLR4 in hepatitis and cirrhosis and maintained expression in hepatocarcinoma. Upregulation of TLR2, TLR4 and their proinflammatory mediators is associated with virus-induced hepatic IFC sequence.

Natural orifice transluminal endoscopy surgery: A review

Minimally invasive surgery started spreading worldwide in 1987, when the first laparoscopic cholecystectomy was performed. Meanwhile, improvement of endoscopic equipment and instruments allowed gastroenterologists to attempt more aggressive endoluminal interventions, even beyond the wall barrier. The first transgastric peritoneoscopy, in 2004, brought to light the concept of natural orifice transluminal endoscopic surgery (NOTES). The idea of incisionless surgery is attractive and has become a new goal for both surgeons and other people interested in this field of investigation. The authors present a review of all developments concerning NOTES, including animal studies and human experience.

In vivo assessment of gastrotomy closure with over-the-scope clips in an experimental model for varicocelectomy (with video)

BACKGROUND Gastrotomy closure remains the major limiting factor for human translation of transgastric surgery; the over-the-scope clip (OTSC) system was proposed as a possibility for this purpose. Transgastric access is good for a pelvic approach, making varicocelectomy a possible indication for natural orifice transluminal endoscopic surgery (NOTES). OBJECTIVE To evaluate the reliability of the OTSC system in vivo after transgastric testicular vessel ligation (varicocelectomy model). DESIGN There were 3 experimental groups (5 animals in each): groups 1 and 3, gastrotomy dilation up to 18 mm, surgery was performed with a double-channel endoscope; group 2, gastrotomy dilation up to 13 mm, surgery was performed with a single-channel endoscope. SETTING Surgical Sciences Research Domain, Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal. INTERVENTIONS Bilateral testicular vessel ligation by transgastric access. Gastrotomy closed with the largest version of OTSC system (12 mm): a single clip in groups 1 and 2, and 2 clips in group 3. Animals were monitored for 2 weeks, killed, and submitted for necropsy. MAIN OUTCOME MEASUREMENTS Adequacy of closure and healing after the use of the OTSC system. Statistical analysis. RESULTS Vessel ligation was easily achieved in all groups. Although differences in the complication rate did not reach statistical significance (P = .099), there was a clear tendency for a better prognosis in groups 2 and 3 than group 1. In fact, only 2 animals from group 1 had complications related to incomplete gastrotomy closure. LIMITATIONS Small number of animals per group; nonrandomized study. CONCLUSIONS The OTSC system was shown to be easy and efficient for gastrotomy closure in a survival experimental model of varicocelectomy, when correctly matching the gastrotomy size with the clip size and/or number.

NOTES performed using multiple ports of entry: Current experience and potential implications for urologic applications.

An isolated transgastric port raises serious limitations in performing natural orifice translumenal endoscopic surgery (NOTES) complex procedures in the urology field. In an attempt to overcome these limitations, several solutions has been advanced, such as the hybrid approach (adding a single abdominal port access) or the pure NOTES combined approach (joining multiple natural orifice ports). To review the current state of experimental and clinical results of multiple ports in NOTES, a literature search of PubMed was performed, seeking publications from January 2002 to 2008 on NOTES. In addition, we looked at pertinent abstracts of annual meetings of the American Urological Association, the European Association of Urology, and the World Congress of Endourology from 2007. Multiple ports of entry seem to be necessary, mainly for moderately complex procedures. Thus, we could find studies using the hybrid approach (combination of transgastric or transvaginal access with a single transabdominal port), or using the pure NOTES combined approach (transgastric and transvesical, transvaginal and transcolonic, or transgastric and transvaginal). There is still limited experience in humans using these approaches, and no comparative studies exist to date. It is predictable that for moderately complex procedures, we will need multiple ports, so the transvaginal-transabdominal (hybrid) approach is the most appealing, whereas in a pure NOTES perspective, the transgastric-transvesical approach seems to be the preferred approach. We are waiting for new equipment and instruments that are more appropriate for these novel techniques.

Peroral esophageal segmentectomy and anastomosis with single transthoracic trocar: a step forward in thoracic NOTES.

BACKGROUND AND STUDY AIMS A transesophageal natural orifice transluminal endoscopic surgery (NOTES) approach has been proposed for thoracic and mediastinal access. Similarly to transgastric surgery, serious limitations remain related to creating an esophagotomy and its safe closure. A hybrid approach in thoracic NOTES could work as an intermediate step before pure transesophageal NOTES. We assessed the benefit of hybrid thoracic NOTES for peroral segmental esophagectomy and subsequent complete esophageal anastomosis with a single transthoracic port. METHODS Two protocols were used to attempt esophago-esophageal anastomosis: ex vivo using a phantom model (n = 5), and in vivo after esophageal mobilization, and segmental esophagectomy achieved using either a gastroscope (flexible) (n = 5) or thoracoscope (rigid) instruments (n = 5). A forward-viewing double-channel endoscope and a transthoracic operative thoracoscope with a working channel were coordinated in order to create a complete single-layer, end-to-end esophageal anastomosis ex vivo as well as in vivo. Feasibility and anastomosis quality were evaluated by inside and outside assessment of: patency, the incorporation of mucosa in all stitches, and a leak test. RESULTS Anastomosis was achieved in all ex vivo experiments and thoracoscopically-led in vivo procedures. All anastomoses were patent, allowing distal passage of the endoscope, with mucosa incorporation. In in vivo experiments, a leak was detected in three animals and corrected with additional stitching. CONCLUSIONS Peroral esophageal anastomosis with a single transthoracic trocar is feasible, which may represent a step forward in thoracic NOTES.

Isotretinoin and inflammatory bowel disease

TO THE EDITOR: We have read the article by Su et al. with great interest (1). In our opinion, there is room for argument in the method and result of their study to reach their conclusion. First, they have used a nonmagnifying colonoscope to identify the pit pattern of each polyp for histology prediction. Using a magnifying colonoscope for screening colonoscopy, lesions are often initially diagnosed on conventional view, and then are evaluated by chromoendoscopy with magnification followed by chromoendoscopy. Thus, we have conducted a prospective study to clarify if dye spraying and magnification used in each step contribute to further endoscopic distinction in comparison to conventional endoscopic view (2). The overall diagnostic accuracy of chromoendoscopy with magnification was 95.6%, which was 10% and 5% significantly better than those of conventional view and chromoendoscopy without magnification, respectively. Su et al. also have previously reported the feasibility of chromoendoscopy with magnification for distinction of colonic polyps (3). In the present study, they provided a similar result of interpreting the pit patterns with a nonmagnifying colonoscope. However, we can hardly identify the pit patterns presented in figures 5 and 8, which are obviously different from those presented in figures 1 and 2. We believed that the pictures of pit patterns shown in figures 1 and 2 were taken by a magnifying colonoscope but not a nonmagnifying one. Moreover, they also provided an extremely high interobserver agreement for interpreting pit patterns, which demonstrated that the kappa value was 0.960 for chromoendoscopy without magnification. Although, interobserver and intraobserver consistency in the endoscopic assessment of colonic pit patterns have been reported to be good for experienced endoscopists, the mean kappa for interobserver agreement was 0.776 (range 0.729–0.836), which was not as high as they described (4). Additionally, despite the fact that the narrow band imaging (NBI) system is newly developed equipment that was not yet worldwide commercially available at the time of their study, even without magnification they also presented an excellent kappa value of NBI of 1.0. To the best of our knowledge, there are no such excellent data concerning pit pattern analysis with a nonmagnifying colonoscope as they have described in the present study. Actually, if nonmagnification could provide the same result as magnification, it would be much more convenient. However, in our opinion, they should provide clear images to show the reliability and reproducibility of their study. In 1999, we developed a prototype NBI system with the assistance of Olympus Optical Co., Ltd., and we have reported that the observation of surface structure (pit pattern) using the NBI with magnification is useful for differentiating neoplasia from nonneoplasia (5). Furthermore, we recently described that the presence of “meshed brown capillary vessels” on magnifying endoscopy with NBI is also useful for differential diagnosis without dye solution (6, 7). Histologically, we also have evaluated microvascular proliferation with CD-31 immunohistochemical staining, and as a result, the diameter of meshed capillary (MC) vessels in normal colonic mucosa and hyperplastic polyps are reported to range from 8 to 12 μm, and are invisible or faintly visible under NBI with magnification. On the other hand, MC vessels in adenomatous or cancerous lesions range from 13 to 20 μm in diameter, and can be clearly visible under NBI with magnification.

Experimental foundation for natural orifice transluminal endoscopic surgery and hybrid natural orifice transluminal endoscopic surgery

Natural orifice transluminal endoscopic surgery (NOTES) is one of the most exciting concepts that has emerged recently in the surgical field. All accesses to the abdominal cavity in the porcine model using natural orifices, e.g. transgastric, transvesical, transcolonic and transvaginal, have been described and explored. The experimental feasibility of all procedures by NOTES was successfully demonstrated in the porcine model using different types of natural orifices. However, few translations to the human have been made. NOTES is in a developmental stage and much work is still needed to refine techniques, verify safety and document efficacy. This paper is an update on the experimental foundation for NOTES and hybrid NOTES and examines the opportunities presented by this new surgical vision.

Safety and efficacy of precut needle-knife fistulotomy

Abstract Objective. Although precut is considered an useful alternative when standard methods of biliary access have failed, there is some controversy about its safety. The study aim was to evaluate the effectiveness of needle-knife fistulotomy (NKF) after a difficult biliary cannulation and whether common bile duct (CBD) diameter influenced complications. Material and methods. Between November 2006 and December 2010, a total of 1087 consecutive patients with naive papilla were submitted to endoscopic retrograde cholangiopancreatography (ERCP) for biliary access, in an affiliated university hospital. If the biliary cannulation was unsuccessful after 12–15 min, a NKF was performed. The main outcomes were biliary cannulation rate, NKF success and post-ERCP complications. Results. Biliary cannulation by standard methods was successful in 883 patients (81%). In the remaining 204 patients, NKF was performed and allowed CBD access in 166 (81%), leading to a 96% cannulation rate. A second ERCP was performed in 25 patients, with an NKF success of 90% and an overall biliary cannulation rate of 98%. The post-ERCP complication rate was 7.9% (n = 16) with a 6.4% pancreatitis rate and no deaths. The complication for patients with a CBD ≤ to 4 mm was 13.9% compared with 4.5% in the remaining patients (OR = 3.39, p = 0.024). Conclusions. NKF is a safe and highly useful method of accessing the CBD in the setting of a difficult biliary cannulation. Despite its safety profile, extra caution is needed when applying NKF to patients with thin bile ducts.