A generic scope actuation system for flexible endoscopes.

BACKGROUND: A scope actuation system assists a surgeon in steering a scope for navigating an operative field during an interventional or diagnostic procedure. Each system is tailored for a specific surgical procedure. The development of a generic scope actuation system could assist various laparoscopic and endoscopic procedures. This has the potential to reduce the deployment and maintenance costs for a hospital, making it more accessible for clinical usage. METHODS: A modular actuation system (for maneuvering rigid laparoscopes) was adapted to enable incorporation of flexible endoscopes. The design simplifies the installation and disassembly processes. User studies were conducted to assess the ability of the system to focus onto a diagnostic area, and to navigate during a simulated esophagogastroduodenoscopy procedure. During the studies, the endoscope was maneuvered with (robotic mode) and without (manual mode) the actuation system to navigate the endoscope's focus on a predefined track. RESULTS: Results show that the robotic mode performed better than the manual mode on all the measured performance parameters including (a) the total duration to traverse a track, (b) the percentage of time spent outside a track while traversing, and (c) the number of times the scope focus shifts outside the track. Additionally, robotic mode also reduced the perceived workload based on the NASA-TLX scale. CONCLUSIONS: The proposed scope actuation system enhances the maneuverability of flexible endoscopes. It also lays the groundwork for future development of modular and generic scope assistant systems that can be used in both laparoscopic and endoscopic procedures.

User interfaces for actuated scope maneuvering in surgical systems: a scoping review.

BACKGROUND: A variety of human computer interfaces are used by robotic surgical systems to control and actuate camera scopes during minimally invasive surgery. The purpose of this review is to examine the different user interfaces used in both commercial systems and research prototypes. METHODS: A comprehensive scoping review of scientific literature was conducted using PubMed and IEEE Xplore databases to identify user interfaces used in commercial products and research prototypes of robotic surgical systems and robotic scope holders. Papers related to actuated scopes with human-computer interfaces were included. Several aspects of user interfaces for scope manipulation in commercial and research systems were reviewed. RESULTS: Scope assistance was classified into robotic surgical systems (for multiple port, single port, and natural orifice) and robotic scope holders (for rigid, articulated, and flexible endoscopes). Benefits and drawbacks of control by different user interfaces such as foot, hand, voice, head, eye, and tool tracking were outlined. In the review, it was observed that hand control, with its familiarity and intuitiveness, is the most used interface in commercially available systems. Control by foot, head tracking, and tool tracking are increasingly used to address limitations, such as interruptions to surgical workflow, caused by using a hand interface. CONCLUSION: Integrating a combination of different user interfaces for scope manipulation may provide maximum benefit for the surgeons. However, smooth transition between interfaces might pose a challenge while combining controls.

Scope actuation system for articulated laparoscopes.

BACKGROUND: An articulated laparoscope comprises a rigid shaft with an articulated distal end to change the viewing direction. The articulation provides improved navigation of the operating field in confined spaces. Furthermore, incorporation of an actuation system tends to enhance the control of an articulated laparoscope. METHODS: A preliminary prototype of a scope actuation system to maneuver an off-the-shelf articulated laparoscope (EndoCAMaleon by Karl Storz, Germany) was developed. A user study was conducted to evaluate this prototype for the surgical paradigm of video-assisted thoracic surgery. In the study, the subjects maneuvered an articulated scope under two modes of operation: (a) actuated mode where an operating surgeon maneuvers the scope using the developed prototype and (b) manual mode where a surgical assistant directly maneuvers the scope. The actuated mode was further assessed for multiple configurations based on the orientation of the articulated scope at the incision. RESULTS: The data show the actuated mode scored better than the manual mode on all the measured performance parameters including (a) total duration to visualize a marked region, (a) duration for which scope focus shifts outside a predefined visualization region, and (c) number of times for which scope focus shifts outside a predefined visualization region. Among the different configurations tested using the actuated mode, no significant difference was observed. CONCLUSIONS: The proposed articulated scope actuation system facilitates better navigation of an operative field as compared to a human assistant. Secondly, irrespective of the orientation in which an articulated scope's shaft is inserted through an incision, the proposed actuation system can navigate and visualize the operative field.

Fabrication of multipoint side-firing optical fiber by laser micro-ablation.

A multipoint, side-firing design enables an optical fiber to output light at multiple desired locations along the fiber body. This provides advantages over traditional end-to-end fibers, especially in applications requiring fiber bundles such as brain stimulation or remote sensing. This Letter demonstrates that continuous wave (CW) laser micro-ablation can controllably create conical-shaped cavities, or side windows, for outputting light. The dimensions of these cavities determine the amount of firing light and their firing angle. Experimental data show that a single side window on a 730 µm fiber can deliver more than 8% of the input light. This can be increased to more than 19% on a 65 µm fiber with side windows created using femtosecond laser ablation and chemical etching. Fine control of light distribution along an optical fiber is critical for various biomedical applications such as light-activated drug-release and optogenetics studies.

An Actuated Variable-View Rigid Scope System to Assist Visualization in Diagnostic Procedures.

OBJECTIVE: Variable-view rigid scopes offer advantages compared to traditional angled laparoscopes for examining a diagnostic site. However, altering the scope's view requires a high level of dexterity and understanding of spatial orientation. This requires an intuitive mechanism to allow an operator to easily understand the anatomical surroundings and smoothly adjust the scope's focus during diagnosis. To address this challenge, the objective of this work is to develop a mechanized arm that assists in visualization using variable-view rigid scopes during diagnostic procedures. METHODS: A system with a mechanized arm to maneuver a variable-view rigid scope (EndoCAMeleon - Karl Storz) was developed. A user study was conducted to assess the ability of the proposed mechanized arm for diagnosis in a preclinical navigation task and a simulated cystoscopy procedure. RESULTS: The mechanized arm performed significantly better than direct maneuvering of the rigid scope. In the preclinical navigation task, it reduced the percentage of time the scope's focus shifted outside a predefined track. Similarly, for simulated cystoscopy procedure, it reduced the duration and the perceived workload. CONCLUSION: The proposed mechanized arm enhances the operator's ability to accurately maneuver a variable-view rigid scope and reduces the effort in performing diagnostic procedures.Clinical and Translational Impact Statement: The preclinical research introduces a mechanized arm to intuitively maneuver a variable-view rigid scope during diagnostic procedures, while minimizing the mental and physical workload to the operator.

Preliminary design and evaluation of a generic surgical scope adapter.

BACKGROUND: Robotic scope assistant systems are used to visualise and navigate the operative field during a laparoscopic surgery. The objective of this work is to design a surgical scope adapter that enables control of different scope types (zero-degree, angulated, and articulated), and can be connected to any six degree-of-freedom robotic manipulator for usage as a robotic scope assistant system. METHODS: A surgical scope adapter compatible with different camera heads and scope types was designed and prototyped. The technical performance of the scope adapter was evaluated and a user study was conducted to assess the human-in-the-loop control. RESULTS: All the subjects were able to navigate the simulated operative field. The scope adapter permits continuous motion to explore the operative field as well as intermittent motion to accurately focus on the targeted anatomical landmarks. CONCLUSION: The modular and generic nature of the surgical scope adapter may enable its usage across different minimally invasive surgeries.

Simultaneous steering and imaging of magnetic particles using MRI toward delivery of therapeutics.

Magnetic resonance navigation (MRN) offers the potential for real-time steering of drug particles and cells to targets throughout the body. In this technique, the magnetic gradients of an MRI scanner perform image-based steering of magnetically-labelled therapeutics through the vasculature and into tumours. A major challenge of current techniques for MRN is that they alternate between pulse sequences for particle imaging and propulsion. Since no propulsion occurs while imaging the particles, this results in a significant reduction in imaging frequency and propulsive force. We report a new approach in which an imaging sequence is designed to simultaneously image and propel particles. This sequence provides a tradeoff between maximum propulsive force and imaging frequency. In our reported example, the sequence can image at 27 Hz while still generating 95% of the force produced by a purely propulsive pulse sequence. We implemented our pulse sequence on a standard clinical scanner using millimetre-scale particles and demonstrated high-speed (74 mm/s) navigation of a multi-branched vascular network phantom. Our study suggests that the magnetic gradient magnitudes previously demonstrated to be sufficient for pure propulsion of micron-scale therapeutics in magnetic resonance targeting (MRT) could also be sufficient for real-time steering of these particles.