scholarly journals Accuracy assessment of target tracking using two 5-degrees-of-freedom wireless transponders

Author(s):  
Roeland Eppenga ◽  
Koert Kuhlmann ◽  
Theo Ruers ◽  
Jasper Nijkamp

Abstract Purpose Surgical navigation systems are generally only applied for targets in rigid areas. For non-rigid areas, real-time tumor tracking can be included to compensate for anatomical changes. The only clinically cleared system using a wireless electromagnetic tracking technique is the Calypso® System (Varian Medical Systems Inc., USA), designed for radiotherapy. It is limited to tracking maximally three wireless 5-degrees-of-freedom (DOF) transponders, all used for tumor tracking. For surgical navigation, a surgical tool has to be tracked as well. In this study, we evaluated whether accurate 6DOF tumor tracking is possible using only two 5DOF transponders, leaving one transponder to track a tool. Methods Two methods were defined to derive 6DOF information out of two 5DOF transponders. The first method uses the vector information of both transponders (TTV), and the second method combines the vector information of one transponder with the distance vector between the transponders (OTV). The accuracy of tracking a rotating object was assessed for each method mimicking clinically relevant and worst-case configurations. Accuracy was compared to using all three transponders to derive 6DOF (Default method). An optical tracking system was used as a reference for accuracy. Results The TTV method performed best and was as accurate as the Default method for almost all transponder configurations (median errors < 0.5°, 95% confidence interval < 3°). Only when the angle between the transponders was less than 2°, the TTV method was inaccurate and the OTV method may be preferred. The accuracy of both methods was independent of the angle of rotation, and only the OTV method was sensitive to the plane of rotation. Conclusion These results indicate that accurate 6DOF tumor tracking is possible using only two 5DOF transponders. This encourages further development of a wireless EM surgical navigation approach using a readily available clinical system.

2020 ◽  
Vol 87 (7-8) ◽  
pp. 451-458
Author(s):  
Oliver Gieseler ◽  
Hubert Roth ◽  
Jürgen Wahrburg

AbstractIn this paper, we present a novel 4 camera stereo system for application as optical tracking component in navigation systems in computer-assisted surgery. This shall replace a common stereo camera system in several applications. The objective is to provide a tracking component consisting of four single industrial cameras. The system can be built up flexibly in the operating room e. g. at the operating room lamp. The concept is characterized by independent, arbitrary camera mounting poses and demands easy on-site calibration procedures of the camera setup. Following a short introduction describing the environment, motivation and advantages of the new camera system, a simulation of the camera setup and arrangement is depicted in Section 2. From this, we gather important information and parameters for the hardware setup, which is described in Section 3. Section 4 includes the calibration of the cameras. Here, we illustrate the background of camera model and applied calibration procedures, a comparison of calibration results obtained with different calibration programs and a new concept for fast and easy extrinsic calibration.


2007 ◽  
Vol 31 (4) ◽  
pp. 509-518 ◽  
Author(s):  
Leila Notash ◽  
Andrew Horne ◽  
Victoria Lee

In this article, an experimental calibration of the constraining linkage of a wire-actuated parallel robot is discussed. The experimental test bed includes a prototyped 4 degrees of freedom wire-actuated parallel manipulator and an optical tracking system. The parallel manipulator employs hybrid actuation of joints and wires and includes a rigid branch to constrain the motion of its mobile platform in roll and yaw rotations. The kinematic calibration of the rigid branch is performed. A point-to-point path is designed for the manipulator and an optical tracking system is used as an external measuring device to track a tool attached to the mobile platform and to register the manipulator poses. The deviation between the actual (measured) pose of the mobile platform and the calculated pose (via direct kinematics using the joint encoders), which could be due to errors in the kinematic parameters, actuators and sensors, is used as the error function.


2013 ◽  
Vol 31 (2) ◽  
pp. 223-231 ◽  
Author(s):  
Rongqian Yang ◽  
Zhigang Wang ◽  
Sujuan Liu ◽  
Xiaoming Wu

Neurosurgery ◽  
2002 ◽  
Vol 50 (6) ◽  
pp. 1393-1397 ◽  
Author(s):  
Takakazu Kawamata ◽  
Hiroshi Iseki ◽  
Takao Shibasaki ◽  
Tomokatsu Hori

Abstract OBJECTIVE Endoscopes have been commonly used in transsphenoidal surgery to treat pituitary tumors, to compensate for the narrow surgical field. Although many navigation systems have been introduced for neurosurgical procedures, there have been few reports of navigation systems for endoscopic operations. This report presents our recently developed, endoscopic, augmented reality (AR) navigation system. METHODS The technology is based on the principles of AR environment technology. The system consisted of a rigid endoscope with light-emitting diodes, an optical tracking system, and a controller. The operation of the optical tracking system was based on two sets of infrared light-emitting diodes, which measured the position and orientation of the endoscope relative to the patient's head. We used the system during endonasal transsphenoidal operations to treat pituitary tumors in 12 recent cases. RESULTS Anatomic, “real,” three-dimensional, virtual images of the tumor and nearby anatomic structures (including the internal carotid arteries, sphenoid sinuses, and optic nerves) were superimposed on real- time endoscopic live images. The system also indicated the positions and directions of the endoscope and the endoscopic beam in three-dimensional magnetic resonance imaging or computed tomographic planes. Furthermore, the colors of the wire-frame images of the tumor changed according to the distance between the tip of the endoscope and the tumor. These features were superior to those of conventional navigation systems, which are available only for operating microscopes. CONCLUSION The endoscopic AR navigation system allows surgeons to perform accurate, safe, endoscope-assisted operations to treat pituitary tumors; it is particularly useful for reoperations, in which midline landmarks may be absent. We consider the AR navigation system to be a promising tool for safe, minimally invasive, endonasal, transsphenoidal surgery to treat pituitary tumors.


2021 ◽  
Vol 11 (9) ◽  
pp. 3947
Author(s):  
Marco Farronato ◽  
Gianluca M. Tartaglia ◽  
Cinzia Maspero ◽  
Luigi M. Gallo ◽  
Vera Colombo

Clinical use of portable optical tracking system in dentistry could improve the analysis of mandibular movements for diagnostic and therapeutic purposes. A new workflow for the acquisition of mandibular kinematics was developed. Reproducibility of measurements was tested in vitro and intra- and inter-rater repeatability were assessed in vivo in healthy volunteers. Prescribed repeated movements (n = 10) in three perpendicular directions of the tracking-device coordinate system were performed. Measurement error and coefficient of variation (CV) among repetitions were determined. Mandibular kinematics of maximum opening, left and right laterality, protrusion and retrusion of five healthy subjects were recorded in separate sessions by three different operators. Obtained records were blindly examined by three observers. Intraclass correlation coefficient (ICC) was calculated to estimate inter-rater and intra-rater reliability. Maximum in vitro measurement error was 0.54 mm and CV = 0.02. Overall, excellent intra-rater reliability (ICC > 0.90) for each variable, general excellent intra-rater reliability (ICC = 1.00) for all variables, and good reliability (ICC > 0.75) for inter-rater tests were obtained. A lower score was obtained for retrusion with “moderate reliability” (ICC = 0.557) in the inter-rater tests. Excellent repeatability and reliability in optical tracking of primary movements were observed using the tested portable tracking device and the developed workflow.


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