Video-based assistance system for training in minimally invasive surgery

In this paper, the development of an assisting system for laparoscopic surgical training is presented. With this system, we expect to facilitate the training process at the first stages of training in laparoscopic surgery and to contribute to an objective evaluation of surgical skills. To achieve this, we propose the insertion of multimedia contents and outlines of work adapted to the level of experience of trainees and the detection of the movements of the laparoscopic instrument into the monitored image. A module to track the instrument is implemented focusing on the tip of the laparoscopic tool. This tracking method does not need the presence of artificial marks or special colours to distinguish the instruments. Similarly, the system has another method based on visual tracking to localize support multimedia content in a stable position of the field of vision. Therefore, this position of the support content is adapted to the movements of the camera or the working area. Experimental results are presented to show the feasibility of the proposed system for assisting in laparoscopic surgical training

Automatic instrument localization in laparoscopic surgery

This paper presents a tracking algorithm for automatic instrument localization in robotically assisted laparoscopic surgery. We present a simple and robust system that doesn't need the presence of artificial marks, or special colours to distinguish the instruments. So, the system enables the robot to track the usual instruments used in laparoscopic operations. Since the instruments are normally the most structured objects in laparoscopic scenes, the algorithm uses the Hough transform to detect straight lines in the scene. In order to distinguish among different instruments or other structured elements present in the scene, motion information is also used. We give in this paper a detailed description of all stages of the system

Real-time 3D tracking of laparoscopy training instruments for assessment and feedback

Assessment of minimally invasive surgical skills is a non-trivial task, usually requiring the presence and time of expert observers, including subjectivity and requiring special and expensive equipment and software. Although there are virtual simulators that provide self-assessment features, they are limited as the trainee loses the immediate feedback from realistic physical interaction. The physical training boxes, on the other hand, preserve the immediate physical feedback, but lack the automated self-assessment facilities. This study develops an algorithm for real-time tracking of laparoscopy instruments in the video cues of a standard physical laparoscopy training box with a single fisheye camera. The developed visual tracking algorithm recovers the 3D positions of the laparoscopic instrument tips, to which simple colored tapes (markers) are attached. With such system, the extracted instrument trajectories can be digitally processed, and automated self-assessment feedback can be provided. In this way, both the physical interaction feedback would be preserved and the need for the observance of an expert would be overcome. Real-time instrument tracking with a suitable assessment criterion would constitute a significant step towards provision of real-time (immediate) feedback to correct trainee actions and show them how the action should be performed. This study is a step towards achieving this with a low cost, automated, and widely applicable laparoscopy training and assessment system using a standard physical training box equipped with a fisheye camera

EVA: Endoscopic Video Analysis of the surgical scene for the assessment of MIS psychomotor skills

The present work covers the first validation efforts of the EVA Tracking System for the assessment of minimally invasive surgery (MIS) psychomotor skills. Instrument movements were recorded for 42 surgeons (4 expert, 22 residents, 16 novice medical students) and analyzed for a box trainer peg transfer task. Construct validation was established for 7/9 motion analysis parameters (MAPs). Concurrent validation was determined for 8/9 MAPs against the TrEndo Tracking System. Finally, automatic determination of surgical proficiency based on the MAPs was sought by 3 different approaches to supervised classification (LDA, SVM, ANFIS), with accuracy results of 61.9%, 83.3% and 80.9% respectively. Results not only reflect on the validation of EVA for skills? assessment, but also on the relevance of motion analysis of instruments in the determination of surgical competence

EVA: Laparoscopic instrument tracking based on endoscopic video analysis for psychomotor skills assessment

INTRODUCTION: The EVA (Endoscopic Video Analysis) tracking system a new tracking system for extracting motions of laparoscopic instruments based on non-obtrusive video tracking was developed. The feasibility of using EVA in laparoscopic settings has been tested in a box trainer setup. METHODS: EVA makes use of an algorithm that employs information of the laparoscopic instrument's shaft edges in the image, the instrument's insertion point, and the camera's optical centre to track the 3D position of the instrument tip. A validation study of EVA comprised a comparison of the measurements achieved with EVA and the TrEndo tracking system. To this end, 42 participants (16 novices, 22 residents, and 4 experts) were asked to perform a peg transfer task in a box trainer. Ten motion-based metrics were used to assess their performance. RESULTS: Construct validation of the EVA has been obtained for seven motion-based metrics. Concurrent validation revealed that there is a strong correlation between the results obtained by EVA and the TrEndo for metrics such as path length (p=0,97), average speed (p=0,94) or economy of volume (p=0,85), proving the viability of EVA. CONCLUSIONS: EVA has been successfully used in the training setup showing potential of endoscopic video analysis to assess laparoscopic psychomotor skills. The results encourage further implementation of video tracking in training setups and in image guided surgery

Systems and technologies for objective evaluation of technical skills in laparoscopic surgery

Minimally invasive surgery is a highly demanding surgical approach regarding technical requirements for the surgeon, who must be trained in order to perform a safe surgical intervention. Traditional surgical education in minimally invasive surgery is commonly based on subjective criteria to quantify and evaluate surgical abilities, which could be potentially unsafe for the patient. Authors, surgeons and associations are increasingly demanding the development of more objective assessment tools that can accredit surgeons as technically competent. This paper describes the state of the art in objective assessment methods of surgical skills. It gives an overview on assessment systems based on structured checklists and rating scales, surgical simulators, and instrument motion analysis. As a future work, an objective and automatic assessment method of surgical skills should be standardized as a means towards proficiency-based curricula for training in laparoscopic surgery and its certification

Vision-based and marker-less surgical tool detection and tracking: a review of the literature

In recent years, tremendous progress has been made in surgical practice for example with Minimally Invasive Surgery (MIS). To overcome challenges coming from deported eye-to-hand manipulation, robotic and computer-assisted systems have been developed. Having real-time knowledge of the pose of surgical tools with respect to the surgical camera and underlying anatomy is a key ingredient for such systems. In this paper, we present a review of the literature dealing with vision-based and marker-less surgical tool detection. This paper includes three primary contributions: (1) identification and analysis of data-sets used for developing and testing detection algorithms, (2) in-depth comparison of surgical tool detection methods from the feature extraction process to the model learning strategy and highlight existing shortcomings, and (3) analysis of validation techniques employed to obtain detection performance results and establish comparison between surgical tool detectors. The papers included in the review were selected through PubMed and Google Scholar searches using the keywords: “surgical tool detection”, “surgical tool tracking”, “surgical instrument detection” and “surgical instrument tracking” limiting results to the year range 2000 2015. Our study shows that despite significant progress over the years, the lack of established surgical tool data-sets, and reference format for performance assessment and method ranking is preventing faster improvement

Ανάπτυξη τεχνολογιών επαυξημένης πραγματικότητας στην ιατρική εκπαίδευση με προσομοιωτές

Στην παρούσα διδακτορική διατριβή παρουσιάζουμε ένα πρωτοπόρο σύστημα εκπαίδευσης και αξιολόγησης βασικών δεξιοτήτων λαπαροσκοπικής χειρουργικής σε περιβάλλον Επαυξημένης Πραγματικότητας (ΕΠ). Το προτεινόμενο σύστημα αποτελεί μια πλήρως λειτουργική πλατφόρμα εκπαίδευσης η οποία επιτρέπει σε χειρουργούς να εξασκηθούν χρησιμοποιώντας πραγματικά λαπαροσκοπικά εργαλεία και αλληλεπιδρώντας με ψηφιακά αντικείμενα εντός ενός πραγματικού περιβάλλοντος εκπαίδευσης. Το σύστημα αποτελείται από ένα τυπικό κουτί λαπαροσκοπικής εκπαίδευσης, πραγματικά χειρουργικά εργαλεία, κάμερα και συστοιχία αισθητήρων που επιτρέπουν την ανίχνευση και καταγραφή των κινήσεων του χειρουργού σε πραγματικό χρόνο. Χρησιμοποιώντας το προτεινόμενο σύστημα, σχεδιάσαμε και υλοποιήσαμε σενάρια εκπαίδευσης παρόμοια με τις ασκήσεις του προγράμματος FLS®, στοχεύοντας σε δεξιότητες όπως η αίσθηση βάθους, ο συντονισμός χεριού-ματιού, και η παράλληλη χρήση δύο χεριών. Επιπλέον των βασικών δεξιοτήτων, το προτεινόμενο σύστημα χρησιμοποιήθηκε για τον σχεδιασμό σεναρίου εξάσκησης διαδικαστικών δεξιοτήτων, οι οποίες περιλάμβανουν την εφαρμογή χειρουργικών clips καθώς και την απολίνωση εικονικής αρτηρίας, σε περιβάλλον ΕΠ. Τα αποτελέσματα συγκριτικών μελετών μεταξύ έμπειρων και αρχαρίων χειρουργών που πραγματοποιήθηκαν στα πλαίσια της παρούσας διατριβής υποδηλώνουν την εγκυρότητα του προτεινόμενου συστήματος. Επιπλέον, εξήχθησαν σημαντικά συμπεράσματα σχετικά με την πιθανή χρήση της ΕΑ στην λαπαροσκοπική προσομοίωση. Η συγκεκριμένη τεχνολογία προσφέρει αυξημένη αίσθηση οπτικού ρεαλισμού και ευελιξία στον σχεδιασμό εκπαιδευτικών σεναρίων, παρουσιάζοντας σημαντικά μικρότερες απαιτήσεις από πλευράς εξοπλισμού σε σύγκριση με τις υπάρχουσες εμπορικές πλατφόρμες. Βάσει των αποτελεσμάτων της παρούσας διατριβής μπορεί με ασφάλεια να εξαχθεί το συμπέρασμα πως η ΕΠ αποτελεί μια πολλά υποσχόμενη τεχνολογία που θα μπορούσε να χρησιμοποιηθεί για τον σχεδιασμό προσομοιωτών λαπαροσκοπικής χειρουργικής ως εναλλακτική των υπαρχόντων τεχνολογιών και συστημάτων.In this thesis we present what is, to the best of our knowledge, the first framework for training and assessment of fundamental psychomotor and procedural laparoscopic skills in an interactive Augmented Reality (AR) environment. The proposed system is a fully-featured laparoscopic training platform, allowing surgeons to practice by manipulating real instruments while interacting with virtual objects within a real environment. It consists of a standard laparoscopic box-trainer, real instruments, a camera and a set of sensory devices for real-time tracking of surgeons’ actions. The proposed framework has been used for the implementation of AR-based training scenarios similar to the drills of the FLS® program, focusing on fundamental laparoscopic skills such as depth-perception, hand-eye coordination and bimanual operation. Moreover, this framework allowed the implementation of a proof-of-concept procedural skills training scenario, which involved clipping and cutting of a virtual artery within an AR environment. Comparison studies conducted for the evaluation of the presented framework indicated high content and face validity. In addition, significant conclusions regarding the potentials of introducing AR in laparoscopic simulation training and assessment were drawn. This technology provides an advanced sense of visual realism combined with a great flexibility in training task prototyping, with minimum requirements in terms of hardware as compared to commercially available platforms. Thereby, it can be safely stated that AR is a promising technology which can indeed provide a valuable alternative to the training modalities currently used in MIS

Laparoscopic Video Analysis for Training and Image Guided Surgery

Automatic analysis of Minimally Invasive Surgical video has the potential to drive new solutions for alleviating needs of safe and reproducible training programs, objective and transparent evaluation systems and navigation tools to assist surgeons and improve patient safety. Surgical video is an always available source of information, which can be used without any additional intrusive hardware in the operating room. This paper is focused on surgical video analysis methods and techniques. It describes authors' contributions in two key aspects, the 3D reconstruction of the surgical field and the segmentation and tracking of tools and organs based on laparoscopic video images. Results are given to illustrate the potential of this field of research, like the calculi of the 3D position and orientation of a tool from its 2D image, or the translation of a preoperative resection plan into a hepatectomy surgical procedure using the shading information of the image. Research efforts are required to further develop these technologies in order to harness all the valuable information available in any video-based surgery