Search

This article reports the results of the 16th National Survey conducted by the Japan Society for Endoscopic Surgery (JSES) for 2020 and 2021. Laparoscopic cholecystectomy was first introduced to Japan in 1990 and has rapidly become popular because of its minimally invasive nature. Since then, the number of objective organs and indications for laparoscopic surgery have gradually expanded. In 2021, 290 787 patients underwent endoscopic surgery in all surgical domains. Of these, 124 614, 110 757, 23 156, 21 771, 6543, 2614, 535, 465, 247, and 58 underwent abdominal, obstetric and gynecologic, thoracic, urological, pediatric, orthopedic, bariatric, mammary and thyroid gland, cardiovascular, and plastic surgery, respectively. Owing to the impact of the coronavirus disease 2019 (COVID-19) infection spread, the incidence of many surgeries decreased in 2020, and levels are only now gradually recovering. However, despite the impact of COVID-19, robot-assisted surgeries were increasingly applied. The rate of complications did not change significantly, indicating that the procedure was performed safely, even with the spread of COVID-19., (© 2024 Asia Endosurgery Task Force and Japan Society of Endoscopic Surgery and John Wiley & Sons Australia, Ltd.)

In Japan, the first endoscopic surgery, a laparoscopic cholecystectomy, was performed in 1990. Since then, operative procedures have been standardized, and the safety and efficacy of endoscopic surgery have been evaluated. In accordance with the social acceptance of endoscopic surgery as a less invasive type of surgery, the number of endoscopic procedures performed has increased in all surgical domains. The Japan Society for Endoscopic Surgery (JSES) has played an important role in the development of endoscopic surgery in Japan. Notably, a technical skills certification system for surgeons was established by the JSES to train instructors on how to teach safe endoscopic surgery. Furthermore, the JSES has conducted a national survey every two years to evaluate the status of endoscopic surgery over time. In 2017, 248 743 patients underwent endoscopic surgery in all surgical domains, such as abdominal, thoracic, mammary and thyroid gland, cardiovascular, obstetrics and gynecology, urologic, orthopedic, and plastic surgery. The 14th National Survey of Endoscopic Surgery conducted by the JSES demonstrated the status of laparoscopic surgery in Japan in 2016-2017., (© 2019 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and John Wiley & Sons Australia, Ltd.)

In Japan, the first endoscopic surgery, a laparoscopic cholecystectomy, was performed in 1990. Since then, the operative procedure has been standardized, and the safety and usefulness of endoscopic surgery have been evaluated. In accordance with the social acceptance of endoscopic surgery as a less-invasive surgery, the number of endoscopic procedures has been increasing in all surgical domains. The Japan Society for Endoscopic Surgery (JSES) has played an important role in the development of endoscopic surgery in Japan. For example, JSES established a technical skills certification system for surgeons to train instructors how to teach safe endoscopic surgery, and the organization performs a national survey every 2 years. In 2015, a total of 211 953 patients underwent endoscopic surgery in all surgical domains, including abdominal, thoracic, mammary and thyroid gland, cardiovascular, obstetrics and gynecology, urologic, orthopedic, and plastic surgery. The course of laparoscopic surgery's development and its current status are reported here based on the results of the most recent questionnaire survey conducted by JSES., (© 2019 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and John Wiley & Sons Australia, Ltd.)

In Japan, the first endoscopic surgery, a laparoscopic cholecystectomy, was performed in 1990. Since then, operative procedures have been standardized, and the safety and usefulness of endoscopic surgery have been evaluated. With the acceptance of endoscopic surgery as less invasive than open surgery, the number of the endoscopic procedures continues to increase in all surgical domains. The Japan Society for Endoscopic Surgery (JSES) has had an important role in the development of endoscopic surgery in Japan. For example, JSES established a technical skills certification system for physicians to train instructors to teach safe endoscopic surgery. Additionally, JSES has performed a national survey every 2 years. In 2013, 178 084 patients underwent endoscopic surgery in all surgical domains, including abdominal, thoracic, mammary and thyroid gland, cardiovascular, obstetrics and gynecology, urologic, orthopedic, and plastic surgery. The development and current status of laparoscopic surgery are reported here based on the results of the most recent questionnaire survey conducted by JSES., (© 2017 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and John Wiley & Sons Australia, Ltd.)

Purpose: We developed and evaluated a visual compensation system that allows surgeons to visualize obscured regions in real time, such that the surgical instrument appears virtually transparent., Methods: The system consists of two endoscopes: a main endoscope to observe the surgical environment, and a supporting endoscope to render the region hidden from view by surgical instruments. The view captured by the supporting endoscope is transformed to simulate the view from the main endoscope, segmented to the shape of the hidden regions, and superimposed to the main endoscope image so that the surgical instruments look transparent. A prototype device was benchmarked for processing time and superimposition rendering error. Then, it was evaluated in a training environment with 22 participants performing a backhand needle driving task with needle exit point error as the criterion. Lastly, we conducted an in vivo study., Results: In the benchmark, the mean processing time was 62.4 ms, which was lower than the processing time accepted in remote surgeries. The mean superimposition error of the superimposed image was 1.4 mm. In the training environment, needle exit point error with the system decreased significantly for experts compared with the condition without the system. This change was not significant for novices. In the in vivo study, our prototype enabled visualization of needle exit points during anastomosis., Conclusion: The benchmark suggests that the implemented system had an acceptable performance, and evaluation in the training environment demonstrated improved surgical task outcomes in expert surgeons. We will conduct a more comprehensive in vivo study in the future.

Purpose: An endoscopic system is needed that presents informative images irrespective of the surgical situation and the number of degrees of freedom in endoscopic manipulation. This goal may be achieved with a virtual reality view for a region of interest from an arbitrary viewpoint. An endoscopic pseudo-viewpoint alternation system for this purpose was developed and tested., Method: Surgical experts and trainees from an endoscopic surgery training course at the minimally invasive surgery training center of Kyushu University were enrolled in a trial of a virtual reality system. The initial viewpoint was positioned to approximate the horizontal view often seen in laparoscopic surgery, with [Formula: see text] between the optical axis of the endoscope and the task surface. A right-to-left suturing task with right hand, based on a task from the endoscopic surgery training course, was selected for testing. We compared task outcomes with and without use of a new virtual reality-viewing system., Result: There was a 0.37 mm reduction in total error ([Formula: see text]) with use of the proposed system. Error reduction was composed of 0.1 mm reduction on the y-axis and 0.27 mm reduction on the x-axis. Experts benefited more than novices from use of the proposed system. Most subjects worked at a pseudo-viewpoint of around 34[Formula: see text]., Discussion: Suturing performance improved with the new virtual reality endoscopic display system. Viewpoint alternation resulted in an overview that improved depth perception and allowed subjects to better aim the marker. This suggests the proposed method offers users better visualization and control in endoscopic surgery.

Background: The purpose of this research was to investigate the usefulness of three-dimensional (3D) endoscopy compared with two-dimensional (2D) endoscopy in neuroendoscopic surgeries in a comparative study and to test the clinical applications., Methods: Forty-three examinees were divided into three groups according to their endoscopic experience: novice, beginner, or expert. Examinees performed three separate tasks using 3D and 2D endoscopy. A recently developed 3D high-definition (HD) neuroendoscope, 4.7 mm in diameter (Shinko Optical Co., Ltd., Tokyo, Japan) was used. In one of the three tasks, we developed a full-sized skull model of acrylic-based plastic using a 3D printer and a patient's thin slice computed tomography data, and evaluated the execution time and total path length of the tip of the pointer using an optical tracking system. Sixteen patients underwent endoscopic transnasal transsphenoidal pituitary surgery using both 3D and 2D endoscopy., Results: Horizontal motion was evaluated using task 1, and anteroposterior motion was evaluated with task 3. Execution time and total path length in task 3 using the 3D system in both novice and beginner groups were significantly shorter than with the 2D system (p < 0.05), although no significant difference between 2D and 3D systems in task 1 was seen. In both the novice and beginner groups, the 3D system was better for depth perception than horizontal motion. No difference was seen in the expert group in this regard. The 3D HD endoscope was used for the pituitary surgery and was found very useful to identify the spatial relationship of carotid arteries and bony structures., Conclusions: The use of a 3D neuroendoscope improved depth perception and task performance. Our results suggest that 3D endoscopes could shorten the learning curve of young neurosurgeons and play an important role in both general surgery and neurosurgery., (Georg Thieme Verlag KG Stuttgart · New York.)

Single port access (SPA) surgery is a laparoscopic procedure using only one transumbilical-placed port. Natural orifice transluminal endoscopic surgery (NOTES) offers the possibility of surgery without visible scars. To address the access and stability problems in SPA and NOTES, we developed a device called rigid-flexible outer sheath. This sheath can be switched between flexible and rigid modes by a novel pneumatic shapelocking mechanism, and it has a double curvature structure that enables it to flex in four directions at the distal end and three directions on the rigid-flexible shaft. The insertion part of the prototype is 300 mm long with a 20 mm outer diameter, and the part is equipped with four working channels. In vivo experiments using a swine show that the outer sheath has high potential for solving access and stability problems. We expect that the outer sheath will be useful for SPA and NOTES.

Recently, robotics systems are focused to assist in Single Port Endoscopic Surgery (SPS). However, the existing system required a manual operation of vision and viewpoint, hindering the surgical task. We proposed a surgical endoscopic robot for SPS with dynamic vision control, the endoscopic view being manipulated by a master controller. The prototype robot consists of a manipulator for vision control, and dual tool tissue manipulators (gripping: 5DOFs, cautery: 3DOFs) can be attached at the tip of sheath manipulator. In particular, this paper focuses on an in vivo experiment. We showed that vision control in the stomach and a cautery task by a cautery tool could be effectively achieved.

Background: Robotic end-effectors for single port endoscopic surgery (SPS) require a manual change of vision field that slows surgery and increases the degrees of freedom (DOFs) of the manipulator., Methods: A new surgical prototype robot has dynamic vision field control and a master controller to manipulate the endoscopic view. It uses positioning (4 DOF) and sheath (2 DOF) manipulators for vision field control, and dual tool tissue manipulators (gripping, 5 DOF; cautery, 3 DOF)., Results: The robot is feasible in vitro. 'Cut and vision field control' (using tool manipulators) was suitable for precise cutting tasks in risky areas; 'cut by vision field control' (using the vision field control manipulator) was effective for rapid macro cutting of tissues. A resection was performed using a combination of both methods., Conclusions: The novel robotic system is feasible, but further studies are needed to address its performance in vivo., (Copyright © 2010 John Wiley & Sons, Ltd.)

Purpose: Pediatric surgeons require highly advanced skills when performing endoscopic surgery, but their experience with such cases tend to be limited in comparison to general surgeons. The aim of this study was to evaluate the effectiveness of basic endoscopic surgery training for less-experienced young pediatric surgeons and then compare their skills with those of general surgeons., Methods: The surgeons (n = 477) subjected to this study underwent a 2-day endoscopic skill training program, consisting of lectures, box training, VR simulator training, tissue training, and live tissue training. The trainees were divided into two groups: P (pediatric surgeons, n = 33) and G (general surgeons, n = 444). The trainees were required to make a continuous suture along a circle measuring 2.5 cm in diameter and the findings were evaluated both before and after training. A statistical analysis was conducted using the unpaired t test., Results: The number of experienced cases totaled 20.8 ± 23.9 in P and 60.6 ± 80.5 in G (p < 0.001). The number of completed sutures before training was 1.4 ± 1.1 in P and 1.9 ± 1.5 in G (p < 0.05). The number of completed sutures after training was 4.1 ± 1.3 in P and 3.9 ± 1.9 in G (p > 0.05). The economy and speed of the forceps improved, however, the number of errors increased., Conclusion: Less-experienced pediatric surgeons improved their surgical skill and ability until reaching almost the same level as that observed in more experienced general surgeons during training, however, the number of errors after training increased in comparison to before training. As a result, this program needs to be modified to reduce the number of errors while enabling pediatric surgeons to master the safe and precise surgical techniques needed in this field.

Natural orifice translumenal endoscopic surgery (NOTES) is a sophisticated form of endoscopic surgery whose use has recently spread rapidly around the world. Although hundreds of reports of animal studies and clinical cases about NOTES have been published since 2004, NOTES is still in the experimental phase. The formation of an iatrogenic incision in the lumenal wall of intraperitoneal organs is a major disadvantage of NOTES. No reliable technique for complete closure has yet been established, and this problem must be resolved before NOTES can be adopted as a routine clinical practice. Several devices for the closure of lumenal incisions in the stomach or colorectum have been developed, and their safety and usefulness have been examined in animal studies and clinical cases. Kyushu University has been involved in furthering the adoption of NOTES as a routine clinical practice, and the Kyushu University Training Center for Minimally Invasive Surgery holds training sessions on endoscopic surgical techniques for surgeons from all over Japan. Studies to develop a navigation system and robotic technology for use with NOTES are also in progress at Kyushu University. The further development of endoscopy-related technologies and equipment, such as robotic technology, is therefore essential to allow the safe, widespread adoption of pure NOTES.

Background: Surgical navigation assists in endoscopic surgeries by enabling surgeons to see concealed lesions and surrounding organs. Successful surgical navigation depends on accurate registration between a medical image and a patient. For accurate point-based registration, it is important to determine the matching order and positions of the markers correctly. It is particularly difficult to determine the order and positions when part of the markers cannot be located on the patient's body or when they cannot be identified in the images., Methods: By using the automatic marker-matching option of the proposed tool, an optimum registration result can be obtained even with the partial loss of markers. In addition, this tool provides an intuitive marker selection interface that displays the registration error of each marker pair in different colors., Results: The efficiency of the described tool in terms of the registration accuracy and time has been confirmed in more than 70 clinical applications. The fiducial registration errors were 1.28 + or - 1.09 mm in ear, nose, and throat surgery and 3.55 + or - 1.30 mm in liver tumor ablation therapy., Conclusions: The proposed automatic matching scheme with marker selection interface was particularly effective where the markers were partly lost or incorrectly identified.

Background: To date, several training and evaluation systems for endoscopic surgery have been developed, such as virtual-reality simulators and box trainers. However, despite current advances in these objective assessments, no functional brain studies during learning of endoscopic surgical skills have been carried out. In the present study, we investigated cortical activation using near-infrared spectroscopy (NIRS) during endoscopic surgical tasks., Study Design: A total of 21 right-handed subjects, comprising 4 surgical experts, 4 trainees, and 13 novices, participated in the study. Suturing and knot-tying tasks were performed in a box trainer. Cortical activation was assessed in all subjects by task-related changes in hemoglobin (Hb) oxygenation using NIRS., Results: In surgical experts and novices with no experience of endoscopic surgical training, we found no changes in oxy-Hb, deoxy-Hb or total-Hb levels in any of the frontal channels. In surgical trainees and one novice with experience of endoscopic surgical training, we found significant increases in oxy-Hb and total-Hb levels in most of the frontal channels. There were significant differences in oxy-Hb and total-Hb levels in CH-19 between surgical experts and trainees (p = 0.02 for both), and between surgical trainees and novices with no experience of endoscopic surgical training (p = 0.008 for both). Furthermore, additional training increased oxy-Hb levels in the frontal cortex of novices with no experience of endoscopic surgical training but had no such effect on surgical experts., Conclusions: The present data suggest that NIRS is a feasible tool for assessing brain activation during endoscopic surgical tasks, and may have a large impact on the future development of teaching, training, and assessment methods for endoscopic surgical skills.

We describe our experience of the development of a endoscopic surgical robot system that can penetrate into the body through the esophagus and perform surgeries in the upper gastric tubes and several organs in the abdominal cavity. In this paper, we describe the results of an experiment using this robot. We describe the configuration of the control system using a gigabit ethernet system named JGN2 for the endoscopic surgical robot. We also describe the results of the first telesurgery experiment using the NOTES (natural orifice transluminal endoscopic surgery) procedure (tele-NOTES), performed at a distance of about 3,750 km.

Background: The first step toward increasing the level of patient safety in endoscopic surgery is for all endoscopic surgeons to acquire fundamental skills, including psychomotor skills, in the preoperation stage of training. The current study aimed to evaluate the effectiveness of virtual reality (VR) simulator training and box training for training the fundamental skills of endoscopic surgery., Methods: For this study, 35 medical students at Kyushu University were divided into three groups: simulator (SIM) group (n = 20), box trainer (BOX) group (n = 20), and control group (n = 15). None of the students had any experience assisting with endoscopic surgery or any previous training for endoscopic surgery. The students in the SIM group underwent training using a VR simulator, the Procedicus MIST, 2 h per day for 2 days. The students in the BOX group underwent training using a box trainer 2 h per day for 2 days. The students in the control group watched an educational video for 30 min. The endoscopic surgical skills of all the students were evaluated before and after training with a task of suturing and knot tying using a box trainer., Results: Although no significant differences were found between the three groups in the total time taken to complete the evaluation task before training, there were significant improvements in the SIM and BOX groups after training compared with the control group. Box training increased errors during the task, but simulator training did not., Conclusion: The findings showed that box training and VR training have different outcomes. The authors expect that the best curriculum for their training center would involve a combination that uses the merits of both methods.

Background: Surgical navigation systems using an optical position sensor have the occlusion problem due to a person or instrument in the line of sight of the camera. In this study, occlusion-free real-time magnetic resonance (MR) scanning with a passive electromagnetic locator is proposed., Methods: A newly developed converter transforms the data of an electromagnetic locator into that of an optical sensor. Registration between the two different coordinate systems is performed for the electromagnetic locator to substitute the optical sensor without modifying the MRI system., Results: An oil marker attached to the electromagnetic locator was identified in real-time MR images. Preliminary results demonstrated the high usability of the electromagnetic locator as an alternative position tracking method in the MR gantry., Conclusions: The occlusion problem of optical sensors is resolved by the proposed method.

We have been developing a surgical robot system with navigation function for abdominal surgery since 2001. Clinical feasibility of the robot has been evaluated by animal experiments. Endoscopic mucosal resection (EMR) and other surgical procedures for Natural Orifice Transluminal Endoscopic Surgery (NOTES) were performed by the combined use of the robot manipulators. In this study, we developed a telecontrol system for the robot to perform an endoscopic abdominal robotic surgery using a robotic telesurgery method. By using a developed system, a telesurgery experiment was conducted between laboratories through LAN including the emulated network delay time. As a result, high-speed data transmission from the master device to the robot could be performed. We also confirmed the implementation of a telecontrol function for the surgical robot. In the near future, we will perform surgeries such as EMR and NOTES with the optimal telecontrol function.

Oblique-viewing endoscopes (oblique scopes) are widely used in medical practice. They are essential for certain procedures such as laparoscopy, arthroscopy and sinus endoscopy. In an oblique scope the viewing directions are changeable by rotating the scope cylinder. Although a camera calibration method is necessary to apply augmented reality technologies to oblique endoscopic procedures, no method for oblique scope calibration has yet been developed. In the present paper, we formulate a camera model and a calibration procedure for oblique scopes. In the calibration procedure, Tsai's calibration is performed at zero rotation of the scope cylinder, then the variation of the external camera parameters corresponding to the rotation of the scope cylinder is modeled and estimated as a function of the rotation angle. Accurate estimation of the rotational axis is included in the procedure. The accuracy of this estimation was demonstrated to have a significant effect on overall calibration accuracy in the experimental evaluation, especially with large rotation angles. The projection error in the image plane was approximately two pixels. The proposed method was shown to be clinically applicable.

We performed a variety of complete total endoscopic general surgical procedures, including colon resection, distal gastrectomy, and splenectomy, successfully with the assistance of the da Vinci computer-enhanced surgical system. The robotic system allowed us to manipulate the endoscopic instruments as effectively as during open surgery. It enhanced visualization of both the operative field and precision of the necessary techniques, as well as being less stressful for the endoscopic operating team. This technological innovation can therefore help surgeons overcome many of the difficulties associated with the endoscopic approach and thus has the potential to enable more precise, safer, and more minimally invasive surgery in the future.

We describe the case of a 51-year-old woman with primary biliary cirrhosis who developed hyperbilirubinemia with transient liver dysfunction after undergoing endoscopic variceral ligation to control hemorrhaging from esophageal varices. After undergoing a variceal ligation, the serum total bilirubin increased from 4.0 mg/dL to 9.5 mg/dL, and the degree of liver failure worsened. She finally had to undergo a liver transplant. We discuss the mechanism of hyperbilirubinemia after endoscopic variceal ligation.

Background: Skin incision has been made directly in the breast for treatment of benign breast tumor in spite of the young age of the patient population., Methods: Small incisions (12 mm, 5 mm, and 2 mm) were made in the extramammary line, and the benign tumors (diagnosed by imaging and aspiration needle cytology) were endoscopically extirpated., Results: The mean age of 36 patients was 27.6 years, and the mean mass size was 3.6 cm (7 masses at maximum). The average operation time per mass was 2.6 hours in the first 18 operations and 1.4 hours in the latter 19 operations. Overall blood loss was 19 mL. Postoperative complications were seen in 2 patients: an extended subcutaneous emphysema due to excessive CO2 gas inflation and a mild burn, both of which were reversible. All patients were extremely satisfied with the cosmetic results of the procedure., Conclusions: Endoscopic removal by the extramammary approach is the best option for benign breast tumors considering the patient's age and the excellent cosmetic results.

The early results of 6 patients with a benign breast mass who underwent an endoscopic extirpation via an extra-mammary incision were presented. Under general anesthesia in either a lateral or supine position, a 12-mm and two 5-mm incisions in the infra-mammary line in 2 patients and in the mid-axillary line in the remaining 4 patients were made. The tumors were then endoscopically extirpated. Preoperative aspiration needle cytology revealed six fibroadenomas in 5 patients and one intraductal papilloma in the other patient. All patients were single females with a mean age of 22.5 years. The maximal size of the masses was 5 cm on average. The average operation time was 3 hours 20 minutes. Regarding postoperative complications, subcutaneous emphysema extending to the neck due to CO2 gas inflation and a burn in the skin were seen in 1 patient each; however, no further treatment was required in these cases. The postoperative hospital stay was 1.7 days on average, and all patients were extremely satisfied with the cosmetic results of the procedure. The cosmetic results are drastically improved by the application of endoscopic removal via extra-mammary approaches, which are newly introduced, for benign breast tumors.

Cosmetic factors in the treatment of breast disease have long been neglected despite the fact that patients are highly concerned about the length and extent of the incision. Recent developments in both endoscopy and endoscopic devices have now made it possible to reach breast mass(es) from small incisions in the axilla. We describe the successful extirpation of a giant fibroadenoma of the breast in a 20-year-old woman, using a 3-mm or 10-mm endoscope and a 3-mm or 5-mm endoscopic device with a transaxillary approach. A scar-free breast with an excellent cosmetic result was achieved by use of this technique and these devices. Benign tumors (both single large tumors and multiple masses) are therefore considered to be ideal candidates for this type of minimally invasive endoscopic surgery.

Fifty cirrhotic patients with esophageal varices underwent endoscopic treatment in a prospective randomized trial carried out to compare variceal ligation with injection sclerotherapy, with respect to safety, efficacy, and complications in the initial session. Twenty-five patients each were treated using endoscopic variceal ligation or endoscopic injection sclerotherapy in the initial session and then only endoscopic injection sclerotherapy for all following sessions. Ligations numbered 4.1 at the initial session. The total number of sessions of endoscopic injection sclerotherapy was 4.0 +/- 1.3 in the endoscopic injection sclerotherapy group compared with 3.6 +/- 1.4 in the endoscopic variceal ligation group. The total volume of the sclerosant used by the end of all the sessions was 23.9 +/- 10.3 ml in the endoscopic variceal ligation group and 39.0 +/- 11.5 ml in the endoscopic injection sclerotherapy group (p < 0.0001). In all patients, complete eradication of the varices was achieved, and at 7 to 15 months follow-up no evidence of recurrence was seen. Adverse effects such as pyrexia, chest pain, and pleural effusion after the initial session were significantly lower in the endoscopic variceal ligation group (p < 0.05), and total bilirubin, serum creatinine, lactate dehydrogenase, and urinary beta 2-microglobulin were significantly increased and PaO2 decreased after endoscopic injection sclerotherapy (p < 0.05). This study shows that endoscopic variceal ligation significantly decreased the adverse effects associated with endoscopic injection sclerotherapy in the initial session, and it is recommended as an alternative to sclerotherapy.

We report here the results of endoscopic injection sclerotherapy performed in 1,000 consecutively treated Japanese patients with esophageal varices. This prospective study covered the period from 1982 to 1990. Variceal bleeding was controlled in 215 (97.7%) of 220 patients. Esophageal varices were completely eradicated in 778 patients (77.8%); the mean number of sessions was 4.2. In only 3 of the 778 patients did esophageal varices of the same size recur. Small, dilated, venous vessels that required additional sclerotherapy in follow-up endoscopy at 3-mo intervals appeared in 171 (22.2%) of 778 patients. The cumulative nonbleeding rate at 5 yr was 94.5% in patients in whom the varices had been eradicated. Deaths caused by upper gastrointestinal bleeding accounted for 2.6% of cases, whereas the rates of liver failure and hepatoma were 4.6% and 47.3%, respectively. The 5-yr cumulative survival rate was 54.1% in patients without concomitant hepatoma; it was 12.0% in patients with hepatomas. Multivariate analysis showed that hepatoma, Child classification, indication (acute, elective or prophylactic) and eradication were independent factors that significantly influenced survival time. This study clearly shows that close follow-up with endoscopy and complete eradication lead to significant reduction in bleeding from esophageal varices and reduction of mortality related to this bleeding.

Endothelial damage after simulated angioscopic insertion was evaluated in 22 dogs by radioimmunoassay of endogenous 6-keto-prostaglandin F1 alpha (stable product of prostacyclin produced by the endothelium) by means of a closed perfusion system and scanning electron microscopy. In 20 dogs, a 1.7 mm diameter polyethylene tube similar in size and physical characteristics to a commercially available angioscope was passed once into the distal venotomy site and out of the proximal venotomy site for a total distance of 15 cm in the left saphenous vein (group A) and 10 times in both directions in the right saphenous vein, destroying all valves (group B). The vein segments were examined immediately after simulated angioscopic insertion and at intervals of 2, 3, and 4 weeks. The remaining two dogs were used as control animals to establish baseline prostacyclin production. All veins were patent when harvested. Scanning electron microscopy revealed globular and contracted endothelial cells in some areas of group A veins, whereas partial longitudinal absence of endothelial cells was noted in group B veins. Intimal coverage was complete by 2 weeks in group A veins and between 3 and 4 weeks in group B veins. Prostacyclin synthesis of group B veins was significantly less than that of group A at day 1 and at 2 weeks after operation (p less than 0.05), reaching that of control vein synthesis by 4 weeks. This study suggests that simulated angioscopic trauma of the luminal surface of the canine saphenous vein had no negative effect on early patency.

The autogenous saphenous venous bypass is accepted as an optimal procedure for distal arterial reconstruction. However, serious complications, including incomplete valvulotomy, laceration of the venous wall and persistent arteriovenous communications, are found in in situ bypasses. To avoid these complications, a new and simple technique using an angioscope in the in situ venous bypass has been developed. Angioscopy prevents tearing of the vein wall and avoids inaccurate incision of the valves.

Background: With the growth and sophistication of laparoscopic surgery, increased attention is now being focused on safety and complications.Methods: In an attempt to address questions regarding the safety of laparoscopic surgery, a retrospective study of the time period from January 1991 to December 1995 was conducted by the Study Group of Endoscopic Surgery in Kyushu, Japan.Results: The response rate was 84.4% (152 of 180 hospitals). During the last 5 years 17,626 patients underwent endoscopic operations and 87.5% (15, 422 patients) had laparoscopic surgery while 12.5% (2,204 patients) underwent thoracoscopic surgery. In 96.6% of the hospitals a minimal open laparotomy was used. Among the various operations, a cholecystectomy was performed in the largest number of patients (13, 787). The total number of complications was 415 (2.7%), of which 156 (37.6%) were related to needle or trocar insertion. Visceral injury was found in 22 patients (0.14%): major vessel injury in 10, gastrointestinal tract injury in 11, and liver injury in one patient. Abdominal wall injury was seen in 79 patients (0.52%), bleeding in 70 (0.46%), and a hernia in 9 (0.06%). Extraperitoneal insufflation occurred in 55 patients (0.36%). There was no mortality. The complication rate significantly decreased year by year after the use of laparoscopic surgery began.Conclusions: The most common complications of laparoscopic surgery are related to needle and trocar insertion. These are preventable by placement under direct vision with verification of the intraperitoneal location of the needle and trocar. [ABSTRACT FROM AUTHOR]

Background: The aim was to develop a new type of robotic wide-angle view endoscope that does not require rotation or bending of the endoscope to move the field of view endoscope allows the surgeon to make extensive observations in a small space. It is safe because it avoids the possibility of hitting organs accidentally. Methods: The system consists of an endoscope with a zoom facility and two wedge prisms at the tip. Each prism is set on its own sleeve at the end of the endoscope. and both prisms rotate independently about the axis of the endoscope. Results: In the iii vim experiment, the high quality of the image was confirmed. and almost whole liver could be observed without the observer moving the endoscope itself. Conclusions: This system provides safe robotic endoscopic surgery because of the high quality of the image. it has great significance for future clinical use. [ABSTRACT FROM AUTHOR]