Image-Based Flexible Endoscope Steering

Manually steering the tip of a flexible endoscope to navigate through an endoluminal path relies on the physician’s dexterity and experience. In this paper we present the realization of a robotic flexible endoscope steering system that uses the endoscopic images to control the tip orientation towards the direction of the lumen. Two image-based control algorithms are investigated, one is based on the optical flow and the other is based on the image intensity. Both are evaluated using simulations in which the endoscope was steered through the lumen. The RMS distance to the lumen center was less than 25% of the lumen width. An experimental setup was built using a standard flexible endoscope, and the image-based control algorithms were used to actuate the wheels of the endoscope for tip steering. Experiments were conducted in an anatomical model to simulate gastroscopy. The image intensity- based algorithm was capable of steering the endoscope tip through an endoluminal path from the mouth to the duodenum accurately. Compared to manual control, the robotically steered endoscope performed 68% better in terms of keeping the lumen centered in the image

Endoscopic stapedectomy our experience

Stapedecomy traditionally is performed using operating microscope. Eventhough it is a time tested procedure, it had its own draw backs. In patients with excessive bony overhang it would bedifficult to access the middle ear cavity using operating microscope. Using Endoscope authors were able to circumvent these difficulties. Endoscopic examination of middle ear cavity was invogue since 1992. 10 Advantages of using endoscope include: Excellent exposure, visualization of entire middle ear cavity with ease, excellent crystal clear images. All the steps of stapedectomycould easily be performed using endoscope. Only flip side being the use of only one hand for the entire procedure as the non dominant hand will be holding the endoscope.

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

Ultra-thin rigid endoscope: Two-photon imaging through a graded-index multi-mode fiber

Rigid endoscopes like graded-index (GRIN) lenses are known tools in biological imaging, but it is conceptually difficult to miniaturize them. In this letter, we demonstrate an ultra-thin rigid endoscope with a diameter of only 125 microns. In addition, we identify a domain where two-photon endoscopic imaging with fs-pulse excitation is possible. We validate the ultra-thin rigid endoscope consisting of a few cm of graded-index multi-mode fiber by using it to acquire optically sectioned two-photon fluorescence endoscopic images of three-dimensional samples.Comment: 17 pages, 15 figures, submitted to Opt. Expres

Ergonomics of the Operative Field in Paediatric Minimal Access Surgery

Imperial Users onl

Flexible lensless endoscope with a conformationally invariant multi-core fiber

The lensless endoscope represents the ultimate limit in miniaturization of imaging tools: an image can be transmitted through a (multi-mode or multi-core) fiber by numerical or physical inversion of the fiber's pre-measured transmission matrix. However, the transmission matrix changes completely with only minute conformational changes of the fiber, which has so far limited lensless endoscopes to fibers that must be kept static. In this letter we report for the first time a lensless endoscope which is exempt from the requirement of static fiber by designing and employing a custom-designed conformationally invariant fiber. We give experimental and theoretical validations and determine the parameter space over which the invariance is maintained

The Use of Audio in Minimal Access Surgery

In minimal access surgery (MAS) (also known as minimally invasive surgery), operations are carried out by making small incisions in the skin and inserting special apparatus into potential body cavities through those incisions. Laparoscopic MAS procedures are conducted in the patient’s abdomen. The aim of MAS is faster recovery, shorter hospitalisation and fewer major post-operative complications; all resulting in lower societal cost with better patient acceptability. The technique is markedly dependent on supporting technologies for vision, instrumentation, energy delivery, anaesthesia, and monitoring. However, in practice, much MAS continues to take longer and be associated with an undesirable frequency of unwanted minor (or occasionally major) mishaps. Many of these difficulties result precisely from the complexity and mal-adaptation of the additional technology and from lack of familiarity with it. A survey of South East England surgeons showed the two main stress factors on surgeons to be the technical difficulty of the procedure and time pressures placed on the surgeon by third parties. Many of the problems associated with MAS operations are linked to the control and monitoring of the equipment. This paper describes work begun to explore ergonomic enhancements to laparoscopic operating technology that could result in faster and safer laparoscopic operations, less surgeon stress and reduce dependence on ancillary staff. Auditory displays have been used to communicate complex information to users in a modality that is complementary to the visual channel. This paper proposes the development of a control and feedback system that will make use of auditory displays to improve the amount of information that can be communicated to the surgeon and his assistant without overloading the visual channel. Control of the system would be enhanced by the addition of voice input to allow the surgeon direct control