Full-thickness resection and lymph-node resection are required for early colorectal cancer and gastric cancer in natural orifice transluminal endoscopic surgery (NOTES). Here we report a needle magnetic device that is capable of easily modifying magnetic force from outside the body and of readily attaching surgical tools to and detaching them from the abdominal wall. Only one hole for setting this device was established on the abdominal wall. This magnetic device allows pure NOTES in gastrointestinal surgery and lymph-node resection. We consider that this device should be more useful for NOTES by using electromagnetic wave controlling. This machine will become useful for NOTES by a wireless control. It was thought that this device was able to become more useful device for NOTES by applying a wireless control unit.

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Natural orifice translumenal endoscopic surgery (NOTES), in its “pure” form without assistant use of any transabdominal cannulae, will require fast and steady insufflation of both intraluminal and intraabdominal spaces through a flexible gastrointestinal endoscope. The use of rapid absorptive carbon dioxide (CO₂) as an insufflating agent, is strongly recommended from the initial step of NOTES, since conventional insufflation using atmospheric air may cause prolonged distension of the downstream bowel and subsequently obstruct the intraabdominal surgical exposure. A dedicated CO₂ insufflator for flexible endoscope (UCR, Olympus) has recently become available in the market. The UCR, however, willnot be applicable for NOTES, since the intraabdominal pressure may be fluctuated with manual “ on-and-off” insufflation. The insufflation may be too slow to perform advanced NOTES procedures, even when using a pressure controlled surgical insufflator. This is simply because the insufflation channel of endoscope is much narrower than the standard insufflation tube. A modified insufflation system specifically designed for NOTES is therefore considered indispensable. A continuous R & D effort, together with meticulous basic/clinical research, is needed to bring this cutting edge technology in the minimally invasive patient care.

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The past 10 years has seen the development of various endoscopic surgical methods which have been appied to assorted gastric disease cases. One drawback however is the amount of time needed to complete the required procedures due to limited maneuverability. In response to this problem we have designed a new concept of miniature robot which, using an endoscopic eye and two manipulators, is able to grasp the soft tissue within the limited spaces of the body. The robot utilizes two forceps style manipulators attached to either side of the upper gastrointestinal scope. By operating these manipulators the surgeon is able to grasp and lift the soft tissue and then dissect by needle knife. We applied the endorobot to an experimental stomach wall resection using a pig subject. The robot was also to approach other abdominal organs and perform various surgical procedures after penetrating the stomach wall. We are currently reducing the robot's size to improve mobility. After further safety tests and experiments we will apply the system to clinical cases and examine its efficiency.

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Introduction: Neuroendoscopic surgery provides a minimally invasive surgical approach for treating hydrocephalus, intracranial tumor access and various other diseases, as an alternative to shunts and invasive open craniotomy. While flexible neuroendoscopic images provide a direct view into cavities within the brain, it is extremely difficult to safely target the region of interest using endoscopic images alone. The continued existence of this limitation represents an important problem leading to abandonment of the procedures, vascular injury, oculomotor palsy and other complications. We propose an integrated navigation system for flexible neuroendoscopy using electromagnetic localizer. The navigation system will provide the location of the tip of flexible endoscope in pre-operative MRI and CT images and the three-dimensional virtual-endoscopic view synchronized with the real endoscopic view.
Material and Methods: An electromagnetic localizer (Aurora ^®, Northern Digital Inc.) was used to track the position of a standard flexible endoscope. We developed the “Neuroendoscopy”module in 3D Slicer software. This new module is specific for the neuroendoscopic navigation surgery. Virtual endoscopic views are graphically rendered using the 3D Slicer. Accuracy and repeatability of the tracking system were evaluated by placing the endoscopic tip at calibrated points on a plastic phantom near an operation table. Accuracy of patient-to-image registration was evaluated using a skull phantom
Results: The electromagnetic localizer exhibited clinically relevant accuracy when tracking the flexible endoscope. Localization accuracy had root-mean-square (RMS) error of 0.89 mm (95% confidence level=0.17mm) when tracking the flexible endoscope near the operating table. The mean error between the tracked endoscope and the internal fiducial landmarks of the skull, within the registered image coordinate frame, was found to be 1.25mm (1.355mm RMS).
Conclusions: The preliminary assessment study lead us to surmise that the electromagnetic localizer is feasible to use in clinical setting and the registration by 3D Slicer provides clinically acceptable accuracy.

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We developed a miniature 2-DOFs bending manipulator of 5-mm diameter for laparoscopic surgery. Bending directions of the mechanism are perpendicular and the mechanisms are controllable respectively. A new wire-connected linkage-driven bending mechanism is built in the manipulator to drive rotate joints for 2-DOFs motion. This manipulator has a central channel of 1.3-mm diameter to drive a pair of blades with electrodes as the tip-side bipolar-coagulator. Surgeons control the manipulator with a grip-type interface in one hand. In mechanical performance evaluations, bending angle was maximum 153.9degrees (from -71.6 to 82.3 degrees) with positioning reproducibility of maximum 0.7mm. About generated force, holding force of bending mechanism was more than 1.82N, and grasping force by a pair of blades as maximum 3.70N. In vivo experiment using a pig (38kg, male) with laparoscopy, we evaluated whether the manipulator performed as a suitable bipolar coagulator for practical clinical use. We were able to coagulate living tissues and occlude blood vessels on the mesenterium completely. In conclusion, our new bending mechanism is useful for miniaturization of the laparoscopic manipulator with the simple structure and high mechanical performance.

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To support needle placements, we developed a compact surgical manipulator system using MRI (magnetic resonance imaging)-guided navigation. The manipulator is designed for use in 430-mm high spaces and the strong magnetic field of an open-MRI. The design uses ultrasonic motors, which are located 750mm away from joints of the manipulator at the center of the MRI. The manipulator can position a puncture needle on the body and pivot around the insertion point to orient the needle. Navigation is performed using MR images of the needle held by the manipulator. While watching these navigational images, the surgeon can maneuver the manipulator to line up the needle trajectory with target, and then manually insert the needle into the target.
The effectiveness of the system was verified with an in-vivo experiment in the MRI (AIRIS-II: Hitachi Medical Corp.). No noticeable deformation in the MR images was observed, even when the manipulator was in motion. Furthermore, the MR images always showed the needle that was moved by the manipulator. This indicates that the manipulator system is accurate enough for needle placement.

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