Development and Validation of a New Generation of Flexible Endoscope for NOTES
ABSTRACT The concept of intraperitoneal flexible endoscopy has created much interest and investigation. Both gastroenterologists with a surgical leaning and surgeons with advanced endoscopy interests are researching the feasibility of this new approach. Current flexible scopes and instruments are extremely limited for use in natural orifice transluminal endoscopic surgery (NOTES). We describe the development of an endoscopic system specifically designed for endoluminal and NOTES procedures and demonstrates benefits and efficacy in benchtop and cadaver models.
In conjunction with industry, an 18-mm 4-channel rigidizing access device was designed. Measurements of the strength (torsional and lifting) of standard endoscopes and the new scope were made. The new device and instruments are used in 8 cadavers to document its feasibility in a variety of specific tasks: endoluminal plication, upper abdomen and lower abdomen visualization, bowel manipulation, solid organ retraction, cholecystectomy, and enterotomy closure.
Benchtop comparison between a standard scope and the new scope showed equal maneuverability but the newer scope had greater force delivery at the tip (0.042 vs 1.96 lb, P < .001) and greater instrument application force (0.09 vs 0.23 lb, P < .002). Introduction of the scope was possible in all cadavers but difficult in cadavers <60 kg. Intragastric manipulation was feasible and exiting the stomach was possible although it required a 2-cm gastrotomy. The scope system was maneuverable in both lower quadrants without difficulty. The upper abdomen was viewable, with variable success in steering the scope between left and right quadrants. The entire gastrointestinal tract was able to be visualized in most cadavers. The scope generated sufficient force to lift and manipulate intraabdominal structures. Cholecystectomy was successful in 5 of 5 attempts.
A new flexible access endoscope with 4 large access channels showed utility in a cadaver model-satisfying some of the requirements for performance of NOTES procedures.
Full-textDOI: · Available from: Lee L Swanstrom, Jul 24, 2015
- SourceAvailable from: Bin Zheng
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- "In the most commonly performed NOTES procedure where the gallbladder is removed through the patient's mouth (Transgastric Cholecystectomy), the tip of the endoscope is twisted backward after entering the abdominal cavity through a transgastric port. In this situation, the distal portion of the scope is flipped over 135 – 175 degrees with respect to the frontal plane  . When displayed on the monitor, the images must be interpreted incompletely upside-down by both the surgeon and assistant controlling the instruments. "
ABSTRACT: Endoscopic surgery performed through patients' natural orifices (NOTES procedures) often require some degree of retroflexion of the operating system. This can cause a misalignment between the displayed image and the actual work plane, leading to performance difficulties. This study investigated the impact of retroflexion on task performance in a simulated environment. Surgeons were required to perform an aiming and pointing task under two experimental conditions: forward-view vs. retroflexed-view. Results showed that both expert and novice surgeons required significantly longer time for completing the task when the scope was retroflexed, compared to when the scope faced forwards. Results address the importance of careful selection of the surgical approach to avoid image retroflexion. Further analysis revealed that the novices were more vulnerable than experts to image distortion with the retroflexed view. This addresses the necessity for surgeons to go through extensive endoscopic training to overcome the visual-motor challenges before they can perform NOTES procedures safely and effectively.Studies in health technology and informatics 01/2011; 163:743-8.
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- "Many disadvantages still limit the chances of early routine operations (i.e., unstable vision, early state of development , etc.) . However, the medical devices companies are racing to solve these problems and the industry is quickly producing futuristically designed instruments to overcome the barriers in TVC progress  . Better cosmetic results, fewer wound infection rates, fewer trocar hernias, reduction or abolition of pain, and shorter hospital stay, although still theoretical, represent the strongest motivations in order to achieve the development in technology that this emerging field requires. "
ABSTRACT: Natural Orifice Transluminal Endoscopic Surgery (NOTES) is an innovative approach in which a flexible endoscope enters the abdominal cavity via the transesophageal, transgastric, transcolonic, transvaginal or transvescical route, combining the technique of minimally invasive surgery with flexible endoscopy. Several groups have described different modifications by using flexible endoscopes with different levels of laparoscopic assistance. Transvaginal cholecystectomy (TVC) consists in accessing the abdominal cavity through a posterior colpotomy and using the vaginal incision as a visual or operative port. An increasing interest has arisen around the TVC; nevertheless, the most common and highlighted concern is about the lack of specific instruments dedicated to the vaginal access route. TVC should be distinguished between "pure", in which the entire operation is performed through the transvaginal route, and "hybrid", in which the colpotomy represents only a support to introduce instruments and the operation is performed mainly by the classic transabdominal-introduced instruments. Although this new technique seems very appealing for patients, on the other hand it is very challenging for the surgeon because of the difficulties related to the mode of access, the limited technology currently available and the risk of complications related to the organ utilized for access. In this brief review all the most recent advancements in the field of TVC's techniques and instrumentations are listed and discussed.Diagnostic and Therapeutic Endoscopy 02/2010; 2010:405469. DOI:10.1155/2010/405469
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ABSTRACT: This study aimed to determine the feasibility of a novel transtracheal endoscopic technique for thoracic and mediastinum evaluation in a canine model. In two dogs under general anesthesia, a transverse incision was made in the right lateral wall of the lower trachea and used as an entrance for thoracic and mediastinum evaluation. Transtracheal thoracoscopic evaluation was possible in both animals. One animal experienced massive subcutaneous emphysema immediately after evaluation of the thoracic cavity and required chest tube drainage. The follow-up endoscopies 2 weeks after surgery showed good healing of the tracheal openings in both animals. The transtracheal approach to the thoracic cavity and mediastinum appears to be feasible. This technique may provide an intriguing platform for the development of natural orifice transluminal surgery (NOTES) in the thoracic cavity.Surgical Endoscopy 04/2010; 24(11):2905-7. DOI:10.1007/s00464-010-1029-7 · 3.31 Impact Factor