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Background: The complexity of laparoscopy requires special training and assessment. Analyzing the streaming videos during the surgery can potentially improve surgical education. The tedium and cost of such an analysis can be dramatically reduced using an automated tool detection system, among other things. We propose a new multilabel classifier, called LapTool-Net to detect the presence of surgical tools in each frame of a laparoscopic video., Methods: The novelty of LapTool-Net is the exploitation of the correlations among the usage of different tools and, the tools and tasks-i.e., the context of the tools' usage. Towards this goal, the pattern in the co-occurrence of the tools is utilized for designing a decision policy for the multilabel classifier based on a Recurrent Convolutional Neural Network (RCNN), which is trained in an end-to-end manner. In the post-processing step, the predictions are corrected by modeling the long-term tasks' order with an RNN., Results: LapTool-Net was trained using publicly available datasets of laparoscopic cholecystectomy, viz., M2CAI16 and Cholec80. For M2CAI16, our exact match accuracies (when all the tools in one frame are predicted correctly) in online and offline modes were 80.95% and 81.84% with per-class F1-score of 88.29% and 90.53%. For Cholec80, the accuracies were 85.77% and 91.92% with F1-scores if 93.10% and 96.11% for online and offline, respectively., Conclusions: The results show LapTool-Net outperformed state-of-the-art methods significantly, even while using fewer training samples and a shallower architecture. Our context-aware model does not require expert's domain-specific knowledge, and the simple architecture can potentially improve all existing methods., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.)

Background: We present a surgical simulator, developed for the training of a laparoscopic surgery and in particular for mesh placement during an inguinal herniorrhaphy., Methods: Major technical issues related to virtual surgery training systems include virtual patient modelling, collision detection and collision response, haptic and graphic rendering, 3-D motion tracking and some special effects, such as bleeding, cauterizing and so on. Among these problems, real-time deformation modelling and collision detection are the most challenging research topics., Results: In this paper, we describe novel approaches addressing the above issues, which have been successfully adopted in our bimanual hernia repair simulator., Conclusion: The implementations of our new collision detection and deformation appear to work well, even at haptic rates for the limited scope of mesh placement training. More sophisticated techniques are needed for full organ deformation especially for blunt dissection simulation., (Copyright 2006 John Wiley & Sons, Ltd.)

In this paper we use the 2D angular spring based mass-spring-damper (AMSD) model to simulate the plastic mesh in a laparoscopic hernia surgery simulator. We propose a physically based method to systematically derive the optimal parameters of the 2D AMSD model. While the traditional 2D MSD model lacks resistance against bending, the 2D AMSD model with optimized parameters can provide correct bending resistance as well as stretching resistance. The simulated mesh is demonstrated to be much more realistic.

Visual realism in laparoscopic surgery simulation is very desirable. Previously, much work has been done to extract the organs and textures from the visible human data (VHD) using various rendering techniques. We present here a technique to extract the true texture from visible human data for the laparoscopic herniorrhaphy simulation. A VHD slice provides texture only in the direction in which it was visualized whereas the surgeons visualize the facet of an organ during a laparoscopic surgery. Our paper describes an approach for the extraction and mapping facet texture from the VHD.

The growing interest in laparoscopic hernia surgery and in surgical simulators has motivated our current research. In this paper, we present our work in simulating the process of stapling used in laparoscopic herniorrhaphy. By connecting two separate deformable preperitoneal meshes together, our model has simulated the repair process for a bilateral hernia correction. The task of mesh placement and stapling of corners was simulated, to allow surgeons to practice their hand-eye coordination. Various deformable models and numerical methods were researched to comply with the real time requirements. The stapling simulator can either be independently used as a part-task (sub-task) trainer or be integrated as a module of a complete VR-based simulator. A phantom device was used to provide haptic-based force feedback during task rehearsals.

During a laparoscopic hernia surgery, a preperitoneal mesh is tacked or stapled to the defect on the inside in order to close the fissure created by the hernia. Here we have proposed and implemented a novel technique for simulating the movement and stapling of the mesh for use in a virtual reality based laparoscopic trainer. The use of particle based system and Mass-Spring model in simulating the movement of the mesh is also discussed.

Simulation of cauterization and irrigation forms an important part of a virtual laparoscopic trainer. Typically, they are carried out to stop the intragastric bleeding due to an accidental cut by the surgeon. In this paper, we present a method to simulate these special visual effects in an integrated fashion in real-time. We have simulated cauterization and irrigation using a particle-based system. A physics-based model is used to simulate accumulation and removal of fluids. The integrated special effects were implemented and tested in a prototype environment.

Simulation of intragastric bleeding due to an accidental cut by the surgeon is an important component of a virtual laparoscopic herniorrhaphy trainer. We present a method for simulating bleeding during laparoscopic hemiorrhaphy here. The various approaches used in previous research work are reviewed and our present approach is justified. Physically based fluid models used in computer graphics are used to simulate bleeding.

Realistic laparoscopic surgical simulators will require real-time graphic imaging and tactile feedback. Our research objective is to develop a cost-effective haptic workstation for the simulation of laparoscopic procedures for training and treatment planning. The physical station consists of a custom-built frame into which laparoscopic trocars and surgical tools may be attached/inserted and which are continuously adjustable to various positions and orientations to simulate multiple laparoscopic surgical approaches. Instruments inserted through the trocars are attached to end effectors of two haptic devices and interfaced to a high speed PC with fast graphics capability. The haptic device transduces 3D motion of the two manually operated surgical instruments into slave maneuvers in virtual space. The slave instrument tips probe the simulated organ. Simulations currently in progress include: 1) Surface-only renderings, deformation, and haptic interactions with elements in the gall gladder surgical field; 2) Voxel-based simulations of the bulk manipulation of tissue; 3) laparoscopic herniorrhaphy. This system provides force feed-forward from the grasped tools to the contact tissue in virtual space, with deformation of the tissue by the virtual probe, and force feedback from the deformed tissue to the operator's hands.