Position Of Surgical Instrument Research Articles

Calibration method for AC electromagnetic positioning systems distorted by eddy currents

Electromagnetic positioning technologies are frequently-used in surgical navigation systems to achieve precise position of surgical instruments in bodies. Still, in operating rooms with complex environments, they would be disturbed by eddy currents of metals. This paper explores a calibration method to mitigate eddy current interference. Initially, The study examined the generation mechanisms of eddy currents and established the expression of secondary magnetic fields they produced, which exhibited a 90-degree phase difference with the AC excitation field. Subsequently, an integral calibration method was proposed, leveraging fields’ distinct phases for separating. Through simulation, various metal materials were modeled to study their impact on magnetic fields. The effectiveness of the calibration method was evaluated by comparing positioning accuracy before and after calibration. Results demonstrated over 80 % average calibration efficiency, effectively mitigating errors induced by metals and enhancing the system’s reliability. This calibration method is crucial for the broader application of electromagnetic positioning systems.

Research on the method of anti-occlusion of surgical instrument tracking based on multi-camera module information fusion

The traditional optical tracking system is easily affected by occlusion and a narrow field of vision, which leads to the failure of surgical instrument tracking. To solve this problem, a multi-target tracking method based on multi-camera module information fusion is proposed. Firstly, a multi-target tracking block is installed at the end of the surgical instrument. A method of solving the end position of surgical instruments based on multi-object tracking is proposed to improve the success rate of surgical instrument tracking. Secondly, motion blur is easy to occur in surgical instrument tracking. A method to reduce the tracking failure caused by motion blur is proposed to improve the sharp edge of the image. Then, a method of information fusion of multi-camera module is proposed to track surgical instruments. Finally, experiments are designed to verify the stability and accuracy of the proposed method. The tracking accuracy is 1.89 ± 0.24 mm.

A low-cost, open-source-based optical surgical navigation system using stereoscopic vision

AbstractComputer-assisted surgical navigation systems have gained popularity in surgical procedures that demand high amounts of precision. These systems aim to track the real-time positioning of surgical instruments in relation to anatomical structures. Typically, state-of-the-art methods involve tracking reflective 3D marker spheres affixed to both surgical instruments and patient anatomies with infrared cameras. However, these setups are expensive and financially impractical for small healthcare facilities. This study suggests that a fully optical navigation approach utilizing low-cost, off-the-shelf parts may become a viable alternative. We develop a stereoscopic camera setup, costing around $120, to track and monitor the translational movement of open-source based fiducial markers on a positioning platform. We evaluate the camera setup based on its reliability and accuracy. Using the optimal set of parameters, we were able to produce a root mean square error of 2 mm. These results demonstrate the feasibility of real-time, cost-effective surgical navigation using off-the-shelf optical cameras.

Uniform gradient magnetic field and spatial localization method based on Maxwell coils for virtual surgery simulation

AbstractWith the development of virtual reality technology, simulation surgery has become a low‐risk surgical training method and high‐precision positioning of surgical instruments is required in virtual simulation surgery. In this paper we design and validate a novel electromagnetic positioning method based on a uniform gradient magnetic field. We employ Maxwell coils to generate the uniform gradient magnetic field and propose two positioning algorithms based on magnetic field, namely the linear equation positioning algorithm and the magnetic field fingerprint positioning algorithm. After validating the feasibility of proposed positioning system through simulation, we construct a prototype system and conduct practical experiments. The experimental results demonstrate that the positioning system exhibits excellent accuracy and speed in both simulation and real‐world applications. The positioning accuracy remains consistent and high, showing no significant variation with changes in the positions of surgical instruments.

Surgical instrument posture estimation and tracking based on LSTM

The surgical navigation system enhances surgical safety and accuracy by providing precise guidance. However, traditional pose estimation algorithms lack real-time performance and accuracy. To address this issue, a multi-average Long Short Term Memory (LSTM) prediction network is designed to maintain sensitivity in estimating the position of surgical instruments and track their random motion trends. Additionally, the spatial coordinates of positioning markers are applied back to the imaging plane, reducing the recognition range and improving algorithm running speed. Experimental results show that the average time of estimation is less than 1ms while ensuring the prediction effect.

Analysis and optimization of surgical electromagnetic tracking systems by using magnetic field gradients

Background: Electromagnetic tracking systems (EMTSs) are widely used in surgical navigation, allowing to improve the outcome of diagnosis and surgical interventions, by providing the surgeon with real-time position of surgical instruments during medical procedures. Objective: the main goal is to improve the limited range of current commercial systems, which strongly affects the freedom of movement of the medical team. Studies are currently being conducted to optimize the magnetic field generator (FG) configuration (both geometrical arrangements and electrical properties) since it affects tracking accuracy. Methods: In this paper, we discuss experimental data from an EMTS based on a developed 5-coils FG prototype, and we show the correlation between position tracking accuracy and the gradients of the magnetic field. Therefore, we optimize the configuration of the FG by employing two different metrics based on i) the maximization of the amplitude of the magnetic field as reported in literature, and ii) the maximization of its gradients. Results: The two optimized configurations are compared in terms of position tracking accuracy, showing that choosing the magnetic field gradients as objective function for optimization leads to higher position tracking accuracy than maximizing the magnetic field amplitude.

An intelligent tracking system for surgical instruments in complex surgical environment

In recent years, the problem of visual occlusion in optical surgical tracking system has attracted widespread attention. To solve this problem, this paper proposes a tracking system for surgical instruments based on data fusion of multicamera modules. Multicamera modules are used to track surgical instruments from different angles to solve the problem of tracking occlusion in monocular tracking. Firstly, occlusion of monocular tracking based on different fiducial marker is analyzed, and a fast calibration method of tracking system for surgical instrument based on multicamera module is proposed. The calibration of the tracking system is mainly divided into the calibration of surgical instruments and the fast calibration between multicamera modules. On this basis, the occlusion detection mechanism is proposed to screen out the data with large errors, and the fuzzy control theory is used to calculate the support degree between different modules. Finally, the serviceable data is fused based on the least square method and the position of surgical instruments is estimated. The average accuracy of static positioning and dynamic trajectory tracking is mm and mm respectively. The real-time performance of the proposed system is 35 frames per second (fps). Compared with the existing optical tracking system, the method proposed in this paper has stronger anti-occlusion and simpler operation.

NextLens-The Next Generation of Surgical Navigation: Proof of Concept of an Augmented Reality System for Surgical Navigation.

Objective The aim of this work was the development of an augmented reality system including the functionality of conventional surgical navigation systems. Methods An application software for the Augmented Reality System HoloLens 2 from Microsoft was developed. It detects the position of the patient as well as position of surgical instruments in real time and displays it within the two-dimensional (2D) magnetic resonance imaging or computed tomography (CT) images. The surgical pointer instrument, including a pattern that is recognized by the HoloLens 2 sensors, was created with three-dimensional (3D) printing. The technical concept was demonstrated at a cadaver skull to identify anatomical landmarks. Results With the help of the HoloLens 2 and its sensors, the real-time position of the surgical pointer instrument could be shown. The position of the 3D-printed pointer with colored pattern could be recognized within 2D-CT images when stationary and in motion at a cadaver skull. Feasibility could be demonstrated for the clinical application of transsphenoidal pituitary surgery. Conclusion The HoloLens 2 has a high potential for use as a surgical navigation system. With subsequent studies, a further accuracy evaluation will be performed receiving valid data for comparison with conventional surgical navigation systems. In addition to transsphenoidal pituitary surgery, it could be also applied for other surgical disciplines.

Mapping Resection Progress by Tool-Tip Tracking during Brain Tumor Surgery for Real-Time Estimation of Residual Tumor.

Surgical resection continues to be the primary initial therapeutic strategy in the treatment of patients with brain tumors. Computerized cranial neuronavigation based on preoperative imaging offers precision guidance during craniotomy and early tumor resection but progressively loses validity with brain shift. Intraoperative MRI (iMRI) and intraoperative ultrasound (iUS) can update the imaging used for guidance and navigation but are limited in terms of temporal and spatial resolution, respectively. We present a system that uses time-stamped tool-tip positions of surgical instruments to generate a map of resection progress with high spatial and temporal accuracy. We evaluate this system and present results from 80 cranial tumor resections. Regions of the preoperative tumor segmentation that are covered by the resection map (True Positive Tracking) and regions of the preoperative tumor segmentation not covered by the resection map (True Negative Tracking) are determined for each case. We compare True Negative Tracking, which estimates the residual tumor, with the actual residual tumor identified using iMRI. We discuss factors that can cause False Positive Tracking and False Negative Tracking, which underestimate and overestimate the residual tumor, respectively. Our method provides good estimates of the residual tumor when there is minimal brain shift, and line-of-sight is maintained. When these conditions are not met, surgeons report that it is still useful for identifying regions of potential residual.

Toward Perception-based Anticipation of Cortical Breach During K-wire Fixation of the Pelvis.

Intraoperative imaging using C-arm X-ray systems enables percutaneous management of fractures by providing real-time visualization of tool to tissue relationships. However, estimating appropriate positioning of surgical instruments, such as K-wires, relative to safe bony corridors is challenging due to the projective nature of X-ray images: tool pose in the plane containing the principal ray is difficult to assess, necessitating the acquisition of numerous views onto the anatomy. This task is especially demanding in complex anatomy, such as the superior pubic ramus of the pelvis, and results in high cognitive load and repeat attempts even in experienced trauma surgeons. A perception-based algorithm that interprets interventional radiographs during internal fixation to infer the likelihood of cortical breach - especially early on, when the wire has not been advanced - might reduce both the amount of X-rays acquired for verification and the likelihood of repeat attempts. In this manuscript, we present first steps towards developing such an algorithm. We devise a strategy for in silico collection and annotation of X-ray images suitable for detecting cortical breach of a K-wire in the superior pubic ramus, including those with visible fractures. Beginning with minimal manual annotations of correct trajectories, we randomly perturb entry and exit points and project the 3D scene using a physics-based forward model to obtain a large number of 2D X-ray images with and without cortical breach. We report baseline results for anticipating cortical breach at various K-wire insertion depths, achieving an AUROC score of 0.68 for 50% insertion. Code and data are available at github.com/benjamindkilleen/cortical-breach-detection.

2D/3D Multimode Medical Image Registration Based on Normalized Cross-Correlation

Image-guided surgery (IGS) can reduce the risk of tissue damage and improve the accuracy and targeting of lesions by increasing the surgery’s visual field. Three-dimensional (3D) medical images can provide spatial location information to determine the location of lesions and plan the operation process. For real-time tracking and adjusting the spatial position of surgical instruments, two-dimensional (2D) images provide real-time intraoperative information. In this experiment, 2D/3D medical image registration algorithm based on the gray level is studied, and the registration based on normalized cross-correlation is realized. The Gaussian Laplacian second-order differential operator is introduced as a new similarity measure to increase edge information and internal detail information to solve single information and small convergence regions of the normalized cross-correlation algorithm. The multiresolution strategy improves the registration accuracy and efficiency to solve the low efficiency of the normalized cross-correlation algorithm.

A virtual platform for real-time performance analysis of electromagnetic tracking systems for surgical navigation

<p class="Abstract">Electromagnetic Tracking Systems (EMTSs) are widely used in surgical navigation, allowing to improve the outcome of diagnosis and surgical interventions, by providing the surgeon with real-time position of surgical instruments during medical procedures. However, particular effort was dedicated to the development of efficient and robust algorithms, to obtain an accurate estimation of the instrument position for distances from the magnetic field generator beyond 0.5 m. Indeed, the main goal is to improve the limited range of current commercial systems, which strongly affects the freedom of movement of the medical team. Studies are currently being conducted to optimize the magnetic field generator configuration (both geometrical arrangements and electrical properties) since it affects tracking accuracy. In this paper, we propose a virtual platform for assessing the performance of EMTSs for surgical navigation, providing real-time results and statistics, and allowing to track instruments both in real and simulated environments. Simulations and experimental tests are performed to validate the proposed virtual platform, by employing it to assess the performance of a real EMTS. The platform offers a real-time tool to analyze EMTS components and field generator configurations, for a deeper understanding of EMTS technology, thus supporting engineers during system design and characterization.</p>

Laser-Generated Leaky Acoustic Wave Imaging for Interventional Guidewire Guidance.

Ultrasound (US) is widely used to visualize both tissue and the positions of surgical instruments in real time during surgery. Previously we proposed a new method to exploit US imaging and laser-generated leaky acoustic waves (LAWs) for needle visualization. Although successful, that method only detects the position of a needle tip, with the location of the entire needle deduced from knowing that the needle is straight. The purpose of the current study was to develop a beamforming-based method for the direct visualization of objects. The approach can be applied to objects with arbitrary shapes, such as the guidewires that are commonly used in interventional guidance. With this method, illumination by a short laser pulse generates photoacoustic waves at the top of the guidewire that propagate down its metal surface. These waves then leak into the surrounding tissue, which can be detected by a US array transducer. The time of flight consists of two parts: 1) the propagation time of the guided waves on the guidewire and 2) the propagation time of the US that leaks into the tissue. In principle, an image of the guidewire can be formed based on array beamforming by taking the propagation time on the metal into consideration. Furthermore, we introduced directional filtering and a matched filter to compress the dispersion signal associated with long propagation times. The results showed that guidewires could be detected at depths of at least 70 mm. The maximum detectable angle was 56.3°. LAW imaging with a 1268-mm-long guidewire was also demonstrated. The proposed method has considerable potential in new clinical applications.

Design of a Five-Degrees of Freedom Statically Balanced Mechanism with Multi-Directional Functionality

A statically balanced mechanism is designed as a potential solution for the positioning of surgical instruments. Its kinematics with five degrees of freedom that decouples linear and angular motions is proposed for that objective. The linear motion of its end effector is provided by a classical parallelogram linkage. To enhance its adaptability, a mechanical system allows re-orienting the position mechanism in three different working modes (horizontal, upward and downward) while preserving its static balance. Based on the mechanical concept, a uniformized static balancing condition that considers all working modes is given. The orientation of the end effector is provided by a spherical decoupled mechanism. It generates a remote center of motion which is highly representative of kinematics in surgery requirements. Based on the mechanism kinematics, the evolution of its gravitational potential energy is studied. Two different mechanical concepts are then proposed to generate a compensating elastic potential energy. A CAD model of the entire mechanism has allowed the estimation of all mechanical parameters for the selection of the appropriate tension springs and for carrying out validation simulations. A prototype of the statically balanced mechanism is fabricated and successfully tested.

Endoscopic Endonasal Approach in the Smart Cyber Operating Theater (SCOT): Preliminary Clinical Application

A next-generation networked operating room, Smart Cyber Operating Theater (SCOT), has been developed in cooperation with medical engineers that integrates standalone medical devices, including intraoperative magnetic resonance imaging (MRI) using the OPeLiNK communication interface. Here, we report the application of this newly developed advanced type of operating theater for the endoscopic endonasal approach (EEA), along with an evaluation of our initial experiences. The study population consisted of 18 patients with parasellar tumor. All patients underwent surgery via the EEA in SCOT. During all procedures, various types of intraoperative information, including electrophysiologic monitoring, anatomic orientation with navigation system, intraoperative MRI, and endoscopic images of the operative field, were collected and stored by OPeLiNK. Furthermore, the intraoperative information was shared with the surgical strategy desk, where a senior neurosurgeon can direct and manage the surgical procedure in real-time. We successfully completed the surgical procedures in SCOT in all cases. Using OPeLiNK, operators in SCOT were able to share various data, such as images obtained intraoperatively and surgical instrument position from navigation systems, as well as images of the surgical field, with senior neurosurgeons at the surgical strategy desk in all cases. Surgically relevant information from these sources was transmitted through an application and displayed to all surgical staff. The necessary nuances were reflected in the surgical procedures. SCOT, which is considered an innovative operation system in neurosurgery, enables both quality and safety in the EEA. Furthermore, the use of SCOT may also contribute to the education of young neurosurgeons.

Analysis of Position Estimation Techniques in a Surgical EM Tracking System

Electromagnetic tracking systems (EMTSs) are widely used in surgical navigation, allowing to improve the outcome of diagnosis and surgical interventions in terms of shorter hospitalization times, reduction of wound pain and increased accuracy, by providing the surgeon with real-time position of surgical instruments during medical procedures. Particular effort must be made on the development of an efficient and robust algorithm to obtain an accurate estimation of the instrument position, for distances from the magnetic field generator beyond 500 mm, which represents the maximum measurement range of current commercial systems, which strongly affects the freedom of movement of the medical team. In this paper we describe two position estimation techniques, based on a model of the magnetic field, then we analyze the robustness to errors and distortions in a set of simulations for different conditions, discussing their pros and cons in a large measurement volume, and we propose a solution by combining the two techniques. The performance of the new technique is tested on experimental data from a novel EMTS prototype, developed to increase the measurement range of current EMTSs, at a mean distance of 600 mm, and a calibration procedure is performed to reduce systematic errors. A mean position and orientation accuracy of 2.2 mm and 0.5° is achieved, along with mean repeatability errors of 1.5 mm and 0.25°, within the specifications required in many surgical applications.

Using conditional generative adversarial networks to reduce the effects of latency in robotic telesurgery.

The introduction of surgical robots brought about advancements in surgical procedures. The applications of remote telesurgery range from building medical clinics in underprivileged areas, to placing robots abroad in military hot-spots where accessibility and diversity of medical experience may be limited. Poor wireless connectivity may result in a prolonged delay, referred to as latency, between a surgeon's input and action which a robot takes. In surgery, any micro-delay can injure a patient severely and, in some cases, result in fatality. One way to increase safety is to mitigate the effects of latency using deep learning aided computer vision. While the current surgical robots use calibrated sensors to measure the position of the arms and tools, in this work, we present a purely optical approach that provides a measurement of the tool position in relation to the patient's tissues. This research aimed to produce a neural network that allowed a robot to detect its own mechanical manipulator arms. A conditional generative adversarial network (cGAN) was trained on 1107 frames of a mock gastrointestinal robotic surgery from the 2015 EndoVis Instrument Challenge and corresponding hand-drawn labels for each frame. When run on new testing data, the network generated near-perfect labels of the input images which were visually consistent with the hand-drawn labels and was able to do this in 299 ms. These accurately generated labels can then be used as simplified identifiers for the robot to track its own controlled tools. These results show potential for conditional GANs as a reaction mechanism, such that the robot can detect when its arms move outside the operating area in a patient. This system allows for more accurate monitoring of the position of surgical instruments in relation to the patient's tissue, increasing safety measures that are integral to successful telesurgery systems.

Development status and application of neuronavigation system

The neuronavigation system is a combination of navigation technology and neurosurgery. It can be used to assist in neurosurgery through three-dimensional reconstruction of medical image data, extraction of lesions, optimal surgical path planning, tracking and positioning of surgical instruments, and real-time intraoperative display. Accurate and maximal treatment of lesions, while effectively avoiding secondary injuries to patients during surgery. Therefore, the development and application of neuronavigation systems are reviewed.

Augmented reality for narrow area navigation in jaw surgery: Modified tracking by detection volume subtraction algorithm.

Jaw surgery based on augmented reality (AR) still has limitations in terms of navigating narrow areas. Surgeons need to avoid nerves, vessels, and teeth in their entirety, not just root canals. Inaccurate positioning of the surgical instrument may lead to positional or navigational errors and can result in cut blood vessels, nerve channels, or root canals. This research aims to decrease the positional error during surgery and improve navigational accuracy by reducing the positional error. The proposed 2D/3D system tracks the surgical instrument, consisting of the shaft and the cutting element, each part being assigned a different feature description. In the case of the 3D position estimation, the input vector is composed of image descriptors of the instrument and the output value consists of 3D coordinates of the cutter. Sample results from a jawbone-maxillary and mandibular jaw-demonstrate that the positional error is reduced. The system, thus, led to an improvement in alignment of the video accuracy by 0.25 to 0.35 mm from 0.40 to 0.55 mm and a decrease in processing time of 11 to 14 frames per second (fps) against 8 to 12 fps of existing solutions. The proposed system is focused on overlaying only on the area to be operated on. Thus, this AR-based study contributes to accuracy in navigation of the deeper anatomical corridors through increased accuracy in positioning of surgical instruments.

Применение навигационных систем в хирургическом лечении пациентов с деструктивной патологией височной кости

The article analyzes the literature data on the use of the navigation system, the specificity of its application in various fields of otosurgery and various methods of application of this technology. The complex anatomy of the temporal bone and the cranial base contains numerous vital structures. Surgery in this region is always associated with the high risk of complications with various damages of the facial nerve, cochlea, semicircular ducts, dura mater, jugular vein bulb and carotid artery. Surgical navigation systems help to accurately determine of the location of anatomical structures during various surgical interventions. The principle of operation is based on tracking the position of surgical instruments due to electromagnetic field or by optical method. The position of the instrument is synchronized with a 3D-model of the anatomical region, built according to CT or MRI. The use of the system allows the surgeon to accurately navigate in the complex anatomy during operations and perform surgical manipulations with the minimal trauma to the surrounding tissues. During the operation, a great deal of time and effort is spent on verification of the middle ear structure, especially when the normal anatomy of the temporal bone is changed due to the pathological process or previous operations. The presence of fixed permanent bone reference points, allowing to calibrate the navigation system, ensures navigation accuracy. The use of a navigation device makes manipulations more accurate and less invasive.