Flexible endoscopes: structure and function--the air and water system.

Flexible endoscopes are complex medical instruments that are easily damaged. To maintain the flexible endoscope in optimum working condition, the user must have a thorough understanding of the structure and function of the instrument. This series of articles will present an in-depth look at the care and handling of these expensive devices. The flexible endoscope is constructed of several systems that operate simultaneously to produce a highly technical, yet effective diagnostic and therapeutic medical device. These systems include the air and water system, the suction and operating channel system, the mechanical system, the endoscopic retrograde cholangiopancreatography (ERCP) elevator system, the optical system, and the electrical system. This first article in a series will focus on the air and water system of the endoscope. A review of the internal and external structure of the flexible endoscope and the functions of the air and water system, including infection control issues, potential problems and evaluation, and prevention of minor problems to avoid expensive repairs, will be addressed.     

Flexible endoscopes: structure and function. The suction and biopsy channel.

Flexible endoscopes are complex medical instruments that are easily damaged. To maintain the flexible endoscope in optimum working condition, the user must have a thorough understanding of the structure and function of the instrument. This is the second in a series of articles presenting an in-depth look at the care and handling of the flexible endoscope. The first article discussed the air and water system. This article will focus specifically on the suction and biopsy channel system. The flexible endoscope is constructed of several systems that operate simultaneously to produce a highly technical, yet effective diagnostic and therapeutic medical device. These systems include the air and water system, the suction or operating channel system, the mechanical system, the endoscopic retrograde cholangiopancreatography (ERCP) elevator system, the optical system, and the electrical system. A review of the internal and external structure of the flexible endoscope and the functions of the channel system, including infection control issues, potential problems and evaluation, and prevention of minor problems to avoid expensive repairs, will be addressed.     

Initial experience of endoscopic phonosurgery with a prototype of the therapeutic rhinolarynx electronic endoscope

We performed endoscopic phonosurgery in a patient with a laryngeal lesion using a prototype of the therapeutic rhino-larynx electronic endoscope connected to a video processor (Asahi Optical Co., Ltd.). This therapeutic electronic endoscope differs from the fiberoptic endoscope, because it contains an instrument channel and a miniature television camera attached to the tip of the endoscope, consisting of a small light-sensitive CCD chip. The dynamic image provided by this system is superior in resolution to that obtained by conventional flexible laryngofiberscopes. Using this therapeutic electronic endoscope and flexible forceps, we succeeded in removing a vocal fold polyp. This endoscope can be passed through the nasal passage into the laryngeal cavity. The therapeutic electronic endoscope is introduced and a clinical case is presented.     

Foreign bodies of the upper gastrointestinal tract: current management

The popularity of the flexible esophagogastroduodenoscope prompted us to reevaluate our management of foreign bodies. In this paper we report our experience and update treatment guidelines. In our series (from December 1975 to May 1982), 74 foreign bodies were removed: 12 with the rigid endoscope, 60 with the flexible endoscope, and two surgically. There was no morbidity or mortality. In the age group 1 to 10 years, there were 15 patients, while the age group 11 to 88 years had 59 patients. Although the rigid endoscope is less expensive and has a larger operating channel, the advantages of the flexible instrument are numerous. Foreign bodies of the pharynx and at the level of the cricopharyngeus muscle are best managed with a rigid endoscope; foreign bodies of the esophagus can be managed with rigid or flexible instruments, but are more easily managed with the latter. Foreign bodies of the stomach and duodenum that require removal can be managed only with the flexible panendoscope.     

支气管内窥镜训练系统在电子软镜插管教学中的应用

目的评估支气管内窥镜训练系统在电子软镜插管教学中的效果,并拟合在该系统上行软镜操作的学习曲线,为软镜训练设置合理的学习终点提供理论依据。方法选取我院2019-01/2020-03期间轮转的30名麻醉专业住院医师规范化培训学员(简称“住培学员”)采用随机数字表法,分为试验组和对照组,每组15名。两组学员均先进行电子软镜插管的理论知识培训,随后对照组学员观摩带教老师对患者实施电子软镜插管5例,并在带教老师指导下,完成5例全麻非困难气道患者的电子软镜插管。试验组学员则在带教老师的指导下,使用支气管内窥镜训练系统完成30次软镜模拟训练,记录每次训练的操作时间,拟合学习曲线。完成培训后,2组学员均采用模拟人头进行5次(N1、N2、N3、N4、N5)软镜操作考核,比较2组学员的操作时间及熟练度评分。结果与对照组比较,试验组学员操作时间短,熟练度评分高,差异有统计学意义(P<0.05);对照组学员自N2次考核后操作时间随着操作次数增加而减少(P<0.05),与N1比较,N3、N4、N5熟练度评分高(P<0.05),与N2、N3比较,N4、N5熟练度评分高(P<0.05)。试验组学员在支气管内窥镜训练系统上模拟软镜操作26(23,27)次后,操作时间基本稳定在90(82,101)s,达到专业级水平。结论使用支气管内窥镜训练系统对麻醉专业住培学员行电子软镜插管训练,安全、高效,且训练26次后可达到学习目标。     

Flexible endoscopes: structure and function. The mechanical system.

Flexible endoscopes are complex medical instruments that are easily damaged. In order to maintain flexible endoscopes in optimum working condition, users must have a thorough understanding of the structure and function of the instrument. This is the third in a series of articles presenting an in-depth look at the care and handling of flexible endoscopes. The first articles discussed the air-water and the suction channels systems. This article will focus specifically on the mechanical system.     

Clinical Experience With a New Type of Rhino-Larynx Electronic Endoscope PENTAX VNL-1530

We observed recordings of pictures obtained from patients with diseases of the larynx by using a new type of rhino-larynx electronic endoscope, PENTAXVNL-1530 connected to a video processor, PENTAX EPM-3300 (Asahi Optical Co., Ltd.). The electronic endoscope differs from the fiberoptic endoscope in that it contains a small light-sensitive charge coupled device (CCD) chip that is attached to the tip of the endoscope. This electronic endoscope has the smallest CCD camera of 5.1 mm in diameter, in the tip portion, and can be passed through the nasal passage into the laryngeal cavity. The dynamic image provided by this system is superior to that obtained by a flexible laryngofiberscope in resolution of the detail.The system with this electronic endoscope was introduced and some clinical cases were presented.     

Electronic videoendoscopy of laryngeal lesions using a new type of rhinolarynx endoscope portion

Patients with laryngeal lesions were observed and the lesions were recorded with an electronic videoendoscope system using the PENTAX EPM-3300 video processor and the PENTAX VNL-1330 endoscope portion. The electronic videoendoscope system differs from the conventional fiberoptic endoscope connected to a video camera in that a small monochrome charge-coupled device (CCD) chip is built in the tip of the endoscope portion. The PENTAX VNL-1330 rhinolarynx endoscope portion has a tip and insertion tube of approximately 4mm in outer diameter to allow its introduction through the nasal passages into the larynx. The dynamic color images provided by this system were superior to those obtained by a conventional rhinolarynx flexible fiberscope connected to a video camera in both quality and resolution of detail. This system should be useful in diagnosing laryngeal lesions.     

Full thickness resection device (FTRD) for endoluminal removal of large bowel tumours: development of the instrument and related experimental studies

We describe a novel device for full thickness resectioning of large bowel lesions. The device has been assessed in experimental studies. Tumours of the large bowel are a frequent disease with increasing incidence figures. If detected at an early stage, local treatment of colon tumours is possible through an endoluminal access. Currently, full thickness resection can only be performed in the rectum with the TEM technique, while snare resection through the flexible endoscope will only allow mucosa resection. We have developed a new device which allows full thickness bowel wall resections up to the splenic flexure. The device, called full thickness resection device (FTRD) has a flexible shaft and a multifunctional front-end. It can be inserted into the colon over a flexible endoscope. After the device is advanced to the tumour, the head can be opened and the tumour, including safety margins, is pulled into the resection chamber inside the device head by means of two tissue graspers. The bowel wall invagination can be visualised with the endoscope to ensure that the tumour is completely pulled into the resection head. The head is then closed and the resection mechanism is activated. A semicircular stapling suture is fired through the bowel wall and a rotary knife is used to cut the tissue. Specimens of > 3 cm can be harvested with FTRD. Prototypes of the device have been successfully tested in a series of animal experiments in parallel to the technical development of the instrument. These experiments could demonstrate that full thickness bowel wall resection is feasible using a flexible instrument and endoscopic visualisation.     

Establishment of pure NOTES procedure using a conventional flexible endoscope: review of six cases of gastric gastrointestinal stromal tumors

An increasing number of reports have recently been published on hybrid natural orifice transluminal endoscopic surgery (NOTES). These reports do not address how to complete an operation with a flexible endoscope alone (pure NOTES), but rather how to combine use of an endoscope and a laparoscope. Surgical procedures using flexible and rigid endoscopes have been developed using different processes and concepts. Recognizing this conceptual difference, we conducted a study to address how to establish a pure NOTES procedure. Six patients with gastric gastrointestinal stromal tumors (GISTs) underwent hybrid NOTES. Each case was retrospectively reviewed to determine the appropriateness of the treatment and the usefulness of the endoscopic submucosal dissection (ESD) method, double-scope method, spaced perforation method, duodenal balloon occlusion method, and loop clip technique. The development of operative procedures that take advantage of the characteristics of flexible endoscopes, even with conventional flexible endoscopic devices and conventional endoscopes alone, may contribute to the realization of pure NOTES.     

Removal of a foreign body from the upper gastrointestinal tract with a flexible endoscope: a prospective study

BACKGROUND AND STUDY AIMS: There have so far been no prospective studies on the value of flexible endoscopy for removing foreign bodies in the upper gastrointestinal tract. This study presents a clinical analysis of accidents with foreign bodies and prospectively evaluates the effectiveness of flexible endoscopy for removing them. PATIENTS AND METHODS: A total of 105 cases of foreign-body ingestion in the upper gastrointestinal tract were evaluated, 29 (27.6 %) in children and 76 (72.4 %) in adults. Thirty patients (28.5 %) had esophageal strictures. RESULTS: Thirty-nine of the foreign bodies (37.1 %) consisted of food and 66 (62.9 %) were not food-related. The success rate of foreign-body extraction using only a conventional flexible endoscope and accessories for treatment was 98.0 %, and with only a polypectomy snare and rat-toothed forceps it was 91.2 %. Complications at the moment of foreign-body removal occurred in nine patients (8.6 %); there was only one (1 %) esophageal perforation. The incidence of complications related to the duration of foreign-body impaction was six (10.5 %) with foreign bodies impacted for up to 24 h, 13 (52.0 %) for those impacted for 24-48 h, and three (60.0 %) for those impacted for 48-72 h ( P < 0.05). CONCLUSIONS: The flexible endoscope is an effective and safe device for removing foreign bodies from the upper gastrointestinal tract, with a high success rate using only the polypectomy snare and the rat-toothed forceps as accessories. If foreign-body impaction lasts for more than 24 h, there is a significant increase in the incidence of complications.     

NOViSE: a virtual natural orifice transluminal endoscopic surgery simulator

Purpose

Natural orifice transluminal endoscopic surgery (NOTES) is a novel technique in minimally invasive surgery whereby a flexible endoscope is inserted via a natural orifice to gain access to the abdominal cavity, leaving no external scars. This innovative use of flexible endoscopy creates many new challenges and is associated with a steep learning curve for clinicians.

Methods

We developed NOViSE—the first force-feedback-enabled virtual reality simulator for NOTES training supporting a flexible endoscope. The haptic device is custom-built, and the behaviour of the virtual flexible endoscope is based on an established theoretical framework—the Cosserat theory of elastic rods.

Results

We present the application of NOViSE to the simulation of a hybrid trans-gastric cholecystectomy procedure. Preliminary results of face, content and construct validation have previously shown that NOViSE delivers the required level of realism for training of endoscopic manipulation skills specific to NOTES.

Conclusions

VR simulation of NOTES procedures can contribute to surgical training and improve the educational experience without putting patients at risk, raising ethical issues or requiring expensive animal or cadaver facilities. In the context of an experimental technique, NOViSE could potentially facilitate NOTES development and contribute to its wider use by keeping practitioners up to date with this novel surgical technique. NOViSE is a first prototype, and the initial results indicate that it provides promising foundations for further development.

     

Development of an interstitial ultrasound applicator for endoscopic procedures: animal experimentation

Biliary cancer is very difficult to treat, mainly because of the advanced stage at which such tumours are detected and the low efficacy of systemic therapeutic modalities like radiotherapy. Palliative measures designed to clear the duct (either by means of surgery or an endoscopic procedure) are presently performed. A relatively noninvasive alternative could be developed to fill this gap in the therapeutic arsenal. To this end, we have designed an interstitial ultrasound (US) applicator suitable for use with a digestive endoscope. This applicator is based on a water-cooled plane transducer that operates at 10 MHz. Although, because the target zone is cylindrical in shape, it might have seemed more logical to use a cylindrical transducer. Nevertheless, a plane transducer was chosen because the pressure field from this kind of emitter decreases less quickly, which means faster and deeper heating. However, to generate coagulation necrosis all around the duct, the applicator has to be rotated around its axis; this is achieved by means of a flexible metallic shaft (2 m in length and 3. 8 mm in diameter) that joins the device's active head (which contains the transducer) to the casing with all the connectors. A holder is fixed at the endoscope channel inlet; it controls the rotation of the applicator. Trials were conducted on pigs. The duodenoscope was introduced via the oesophagus down through the duodenum as far as the hepatopancreatic ampulla. Using a guide wire, the applicator was navigated into the duct via the endoscope instrument channel. Well defined, reproducible volumes of coagulation necrosis with a diameter of 20 mm were generated in the biliary tissue and the liver. These promising results indicate that this kind of endoscopic US delivery system may represent an effective tool for the treatment of biliary tumours in humans. An Independent Ethics Committee recently approved preliminary clinical trials of this applicator.     

贵州省10所综合医院内镜消毒质量调查

为贯彻《内镜清洗消毒技术操作规范》,了解医院内镜清洗消毒质量,采用现场检查和采样检测方法,对贵州省10所综合医院内镜清洗消毒质量进行了调查。结果,6所省级医院软式内镜及附件采样83份,合格率56.63%;腹腔镜及各种器械钳采样67份,合格率95.52%。4所市级医院胃镜共监测126份样,合格率47.20%。从内镜采样标本中检出金黄色葡萄球菌构成比5.56%,大肠埃希氏菌11.11%,铜绿假单胞菌8.73%,H IV抗体初筛阳性1例。结论,医院内镜清洗消毒质量不合格现象严重,其中软式内镜消毒效果检测合格率较低。     

Tracking of a bronchoscope using epipolar geometry analysis and intensity-based image registration of real and virtual endoscopic images

This paper describes a method for tracking the camera motion of a flexible endoscope, in particular a bronchoscope, using epipolar geometry analysis and intensity-based image registration. The method proposed here does not use a positional sensor attached to the endoscope. Instead, it tracks camera motion using real endoscopic (RE) video images obtained at the time of the procedure and X-ray CT images acquired before the endoscopic examination. A virtual endoscope system (VES) is used for generating virtual endoscopic (VE) images. The basic idea of this tracking method is to find the viewpoint and view direction of the VES that maximizes a similarity measure between the VE and RE images. To assist the parameter search process, camera motion is also computed directly from epipolar geometry analysis of the RE video images. The complete method consists of two steps: (a) rough estimation using epipolar geometry analysis and (b) precise estimation using intensity-based image registration. In the rough registration process, the method computes camera motion from optical flow patterns between two consecutive RE video image frames using epipolar geometry analysis. In the image registration stage, we search for the VES viewing parameters that generate the VE image that is most similar to the current RE image. The correlation coefficient and the mean square intensity difference are used for measuring image similarity. The result obtained in the rough estimation process is used for restricting the parameter search area. We applied the method to bronchoscopic video image data from three patients who had chest CT images. The method successfully tracked camera motion for about 600 consecutive frames in the best case. Visual inspection suggests that the tracking is sufficiently accurate for clinical use. Tracking results obtained by performing the method without the epipolar geometry analysis step were substantially worse. Although the method required about 20 s to process one frame, the results demonstrate the potential of image-based tracking for use in an endoscope navigation system.     

Endoscopic treatment of a mid-esophageal diverticulum

Mid-esophageal diverticulum is a medical rarity. Only patients in whom the condition is symptomatic should receive treatment. Minimally invasive surgery via a thoracoscopic approach is currently the preferred treatment for the condition. This case report describes a 63-year-old woman with a symptomatic mid-esophageal diverticulum, which was successfully treated by endoscopic diverticulotomy using a needle-knife through a flexible endoscope.     

Water intubation of the sigmoid colon: water instillation speeds up left-sided colonoscopy.

BACKGROUND AND STUDY AIMS: Rapid passage through the sigmoid and descending colon is important during flexible colonoscopy, and colonoscopists have developed several techniques and tricks for achieving this. The present study was designed to explore the effect of instilling 200 ml of water into the first bend of the sigmoid on the speed of passage of the endoscope from the rectum to the left colonic (splenic) flexure. PATIENTS AND METHODS: A prospective study of 100 successive single-handed colonoscopies was carried out, using randomly either the water intubation technique (50 patients) or the traditional method (50 controls) to compare the time needed to pass the endoscope from the rectum to the left colonic flexure. RESULTS: The results indicate that water intubation allowed the endoscope to be advanced through the sigmoid and descending colon in a median time (fiftieth percentile) of 154.5 seconds, compared to 223.5 seconds using the traditional technique. Water intubation speeds up the insertion time by 31%. This difference was highly significant statistically (P<0.0001). The difference remained significant when the data for men and women were analyzed separately. There was no statistically significant difference in the formation of N loops, or in incidentally formed alpha loops between the two study groups. CONCLUSION: The water intubation technique is more efficient than the traditional method, particularly in difficult left-sided colonoscopies, but it is equally safe.     

Flexible endoscopic robot

Natural orifice transluminal endoscopic surgery (NOTES) is a novel surgical procedure during which abdominal operations can be performed with an endoscope passed through a natural orifice through an internal incision in the stomach, vagina, bladder or colon. NOTES is still evolving and many barriers stand on its way before it can gain acceptance in modern surgical practice. Effective access to the peritoneal cavity, closure techniques of the natural orifice access sites, development of a multitasking platform to accomplish procedures and support for special orientation are only a handful of its known limitations. Although the endoscope and conventional tools are useful for simple procedures, many important and complicated procedures are currently not possible due to limitation of degree of freedom (DOF) of the end effectors. We have developed a Master and Slave Transluminal Endoscopic Robot (MASTER) with nine degrees of freedom (DOF) in end effectors, which are long and flexible so as to enhance endoscopic procedures and NOTES. Using MASTER we have successfully performed endoscopic sub-mucosal dissections (ESD) to segmental hepatectomies in animal models. Thus, the MASTER robotic system shows great potential to perform new surgical procedures that are otherwise not possible with conventional endoscopic tools.     

FOCUS-PDCA管理对软式内镜消毒质量的改善作用

目的:探讨FOCUS-PDCA管理对软式内镜消毒质量的改善作用。方法:采用便利抽样法,选取2018年1月—2020年2月在商丘市第一人民医院内镜中心的124个软式内镜和23名护士为研究对象,将2018年1月—2019年1月采取常规方式消毒处理的软式内镜设为对照组（ n=62）;将2019年2月—2020年2...     

改良鱼骨图在软式内镜护理人员职业防护中的应用效果

目的探讨改良鱼骨图在软式内镜护理人员职业防护中的应用效果。方法选取我院2017年7月至2019年7月内镜科从事软式内镜操作的29名护理人员为研究对象,采用改良鱼骨图从人、物、环、法、管理方面寻找原因,制定相应改进措施。记录实施前后护理人员不良事件发生率及职业防护认知水平。结果改良鱼骨图实施后护理人员职业防护认识水平高于实施前(P<0.05),不良事件发生率低于实施前(P<0.05)。结论改良鱼骨图应用于软式内镜护理人员职业防护中,可提高护理人员职业防护认知水平,降低不良事件发生率,增强安全意识。