Scientific Studies
Welcome to the Scientific Studies section, where we present the rigorous validation and real-world implementation of our system through extensive scientific research. Explore the diverse range of studies conducted in various healthcare settings, unveiling how our technology effectively tackles specific challenges, enhances patient outcomes, and propels advancements in the field of healthcare.
Journal Papers
Peer-reviewed journal papers that highlight the clinical application of our system. These papers provide robust evidence of our technology's efficacy, reliability, and positive outcomes in various medical contexts.
Frameless stereotactic brain biopsy and external ventricular drainage placement using the RONNA G4 system
Robot-assisted stereotactic procedures
are among the latest technological improvements in neurosurgery. Lately, robotics has become relevant with increased use in several fields due to precision, reliability and spatial accuracy and dexterity, with improvements in the safety and efficacy of neurosurgical procedures [1, 2]. Robotic-assisted neurosurgical stereotactic procedures used widely are tumor biopsies, deep brain stimulation electrodes placement, stereoelectroencephalographic electrodes placement, external ventricular drainage (EVD) placement, endoscopy, etc. [1–9].
The RONNA G4, the fourth generation of the robotic neuronavigation system RONNA is regularly used as a standard neurosurgical tool for precise preoperative planning and frameless neuronavigation [3, 7, 8, 10].
Herein, to the best of our knowledge, we report the first EVD placement using the RONNA robotic system preformed together with brain biopsy, all in one procedure.
Brain scans
Brain 2d and 3d view
Operation procedure
Authors: Raguž, M.; Dlaka, D.; Orešković, D.; Kaštelančić, A.; Chudy, D.; Jerbić, B.; Šekoranja, B.; Šuligoj, F.; Švaco, M.
Journal: Journal of Surgical Case Reports
Year: 2022 (5), rjac151
Link to the Paper : https://doi.org/10.1093/jscr/rjac151
Clinical application of the RONNA G4 system – preliminary validation of 23 robotic frameless brain biopsies
Aims
To report the outcomes of robot-assisted brain biopsies performed using a novel RONNA G4 system. The system was developed by a research group from the Faculty of Mechanical Engineering and Naval Architecture and a team of neurosurgeons from Dubrava University Hospital, University of Zagreb School of Medicine.
Methods
This prospective study included 49 biopsies analyzed during one year: 23 robotic frameless and 26 frame-based Leksell stereotactic biopsies. We analyzed the presenting symptoms, tumor range and location, postoperative complications, pathohistological diagnosis, diagnostic yield, as well as operation and hospitalization duration. The target point error was calculated to assess the accuracy of the RONNA system.
Results
No postoperative mortality, morbidity, or infections were observed. In the frameless robotic biopsy group, only one pathohistological diagnosis was inconclusive. Therefore, the diagnostic yield was 95.6% (22/23), similar to that of the framebased Leksell stereotactic biopsy group (95.1% or 25/26). The average target point error in the frameless robotic biopsy group was 2.15 ± 1.22 mm (range 0.39-5.85).
Conclusion
The RONNA G4 robotic system is a safe and accurate tool for brain biopsy, although further research warrants a larger patient sample, comparison with other robotic systems, and a systematic analysis of the entry and target point errors.
RONNA historical development.
RONNA G4 surgical workflow
Authors: Dlaka, D.; Švaco, M.; Chudy, D.; Jerbić, B.; Šekoranja, B.; Šuligoj, F.; Vidaković, J.; Almahariq, F.; Romić, D.; Raguž, M.
Journal: Croat Med J
Year: 2021, 62 (4), 318–327.
Link to the Paper : https://doi.org/10.3325/cmj.2021.62.318
Frameless stereotactic brain biopsy: A prospective study on robot-assisted brain biopsies performed on 32 patients by using the RONNA G4 system
Background
We present a novel robotic neuronavigation system (RONNA G4), used for precise preoperative planning and frameless neuronavigation, developed by a research group from the University of Zagreb and neurosurgeons from the University Hospital Dubrava, Zagreb, Croatia. The aim of study is to provide comprehensive error measurement analysis of the system used for the brain biopsy.
Methods
Frameless stereotactic robot-assisted biopsies were performed on 32 consecutive patients. Post-operative CT and MRI scans were assessed to precisely measure and calculate target point error (TPE) and entry point error (EPE).
Results
The application accuracy of the RONNA system for TPE was 1.95 ± 1.11 mm, while for EPE was 1.42 ± 0.74 mm. The total diagnostic yield was 96.87%. Linear regression showed statistical significance between the TPE and EPE, and the angle of the trajectory on the bone.
Conclusion
The RONNA G4 robotic system is a precise and highly accurate autonomous neurosurgical assistant for performing frameless brain biopsies.
Authors: Dlaka, D.; Švaco, M.; Chudy, D.; Jerbić, B.; Šekoranja, B.; Šuligoj, F.; Vidaković, J.; Romić, D.; Raguž, M
Journal: Int J Med Robot
Year: 6 February 2021, rcs.2245.
Link to the Paper : https://doi.org/10.1002/rcs.2245
Stereotactic Neuro-Navigation Phantom Designs: A Systematic Review
In the vast majority of keyhole stereotactic neurosurgical interventions, namely biopsies, deep brain stimulation (DBS), stereoelectroencephalography (SEEG), ventricular puncture, and catheter placement, straight cylindrical non-deformable instruments are introduced into the intracranial region of interest, aiming at the planned target. The primary objective of any keyhole neurosurgical procedure is to reach the planned target with minimal deviation, i.e., targeting error, while avoiding blood vessels (Figures 1A,B). Furthermore, it is necessary to avoid functional and eloquent brain areas, such as the sensory and motor cortex areas, eloquent temporal regions, and the primary visual cortex (Figure 1C). By avoiding visible vessels and critical areas within the brain while navigating through a narrow entry point (two to 30 millimeters in diameter) toward the target point ensures maximum safety and minimizes potential complications. The diameter of the instruments ranges from two (various probes and electrodes) to roughly 15 mm (larger tools such as endoscopes), while the target size can vary significantly, from a few millimeters to a couple of centimeters (e.g., large tumors).
Avoiding all visible vessels is critical in stereotactic planning.
Types of errors measured at the target and entry points.
Authors: Švaco, M.; Stiperski, I.; Dlaka, D.; Šuligoj, F.; Jerbić, B.; Chudy, D.; Raguž, M.
Journal: Front. Neurorobot.
Year: 2020, 14, 549603.
Link to the Paper : https://doi.org/10.3389/fnbot.2020.549603
Fully Automated Point-Based Robotic Neurosurgical Patient Registration Procedure
In this study, we have introduced a framework for an automatic patient registration procedure using freely distributed fiducial markers within a robot application in neurosurgery. The localization procedures in the image space in the physical space are fully automated. We have developed a novel algorithm for finding the point pair correspondence between freely distributed fiducial markers in the image and in the physical space. The algorithm introduces a similarity matrix to maximize the possibility of successful point pairing and to remove the potential outlier points.
Success rate of the correspondence algorithm with the data from 5 CT scans
Success rate of the correspondence algorithm with the data from 12 CT scans
Authors: Šuligoj, F.; Jerbić, B.; Švaco, M.; Šekoranja, B.
Journal: International Journal of Simulation Modelling
Year: 2018, 17 (3), 458–471
Link to the Paper : https://doi.org/10.2507/IJSIMM17(3)442
Influence of the Localization Strategy on the Accuracy of a Neurosurgical Robot System
Precise navigation of surgical instruments
is one of the most important features of autonomous surgical robots. In this paper, we introduce a concept of robot localization strategy and analyse its influence on the overall application error of a robot system for frameless stereotactic neurosurgery named RONNA. Localization strategies utilize specific angles at which the robot can approach a target point, orientations, and types of movement during the procedure of physical space fiducial marker localization and positioning to the target points. The localization strategies developed in this study are a neutral orientation strategy (NOS), an orientation correction strategy (OCS) and a joint displacement minimization strategy (JDMS). To evaluate the robot positioning performance with the localization strategies applied, we performed laboratory phantom measurements using a different number of fiducial markers in the registration procedure. When three, four, and five fiducial markers were used, the application error for the NOS was 1.571±0.256 mm, 1.397±0.283 mm, and 1.327±0.274 mm, and for the OCS, it was 0.429±0.133 mm, 0.284±0.068mm, and 0.260±0.076 mm, respectively. The application error for the JDMS was 0.493±0.176 mm with four and 0.369±0.160 mm with five fiducial markers used.
Authors: Šuligoj, F.; Jerbić, B.; Šekoranja, B.; Vidaković, J.; Švaco, M.
Journal: Transactions of FAMENA
Year: 2018, 42 (2), 27–38.
Link to the Paper : https://doi.org/10.21278/TOF.42203
Brain Biopsy Performed with the RONNA G3 System: A Case Study on Using a Novel Robotic Navigation Device for Stereotactic Neurosurgery
Background
Robotic neuronavigation is becoming an important tool for neurosurgeons. We present a case study of a frameless stereotactic biopsy guided by the RONNA G3 robotic neuronavigation system.
Methods
A 45 year-old patient with a history of vertigo, nausea and vomiting was diagnosed with multiple periventricular lesions. Neurological status was unremarkable. A frameless robotic biopsy of a brain lesion was performed.
Results
Three tissue samples were obtained. There were no intraoperative or postoperative complications. Histological analysis showed a B-cell lymphoma. After merging the preoperative CT scan with the postoperative MRI and CT scans, the measured error between the planned and the postoperatively measured entry point was 2.24 mm and the measured error between the planned and postoperatively measured target point was 2.33 mm.
Conclusions
The RONNA G3 robotic system was used to navigate a Sedan brain biopsy needle to take tissue samples and could be a safe and precise tool for brain biopsy.
Authors: Šuligoj, F.; Jerbić, B.; Švaco, M.; Šekoranja, B.
Journal: The International Journal of Medical Robotics and Computer Assisted Surgery
Year: 2017, 1–7.
Link to the Paper : https://doi.org/10.1002/rcs.1884
Position Planning for Collaborating Robots and Its Application in Neurosurgery
The application of robotic manipulators in medicine today is a very current field of research.
Despite this, there are still a large number of problems that occur in the preparation of most robotized operating procedures. One of the main ones is the positioning of the robot relative to the patient. When installing robots in relation to pre-known operating points, it is necessary to ensure an efficient position of the robot from which all given movements can be made without kinematic problems and collisions. The paper presents a method for planning spatial deployment of robots suitable for use in neurosurgery. The developed method is based on the multi-target optimization of the goal function, which is composed of criteria that combine the spatial maneuverability of robots with the avoidance of collisions. The application of the developed method was validated on a two-handed robot system.
Authors: Vidaković, J.; Jerbić, B.; Švaco, M.; Šuligoj, F.; Šekoranja, B.
Journal: Tehnicki vjesnik - Technical Gazette
Year: 2017, 24 (6)
Link to the Paper : https://doi.org/10.17559/TV-20170213110534
Novel Robotic Neuronavigation System: RONNA G3
This paper presents a novel robotic neuronavigation system, RONNA G3,
developed for frameless stereotactic navigation based on standard industrial robots. The basic version of the RONNA G3 system has three main components: a robotic arm on a universal mobile platform, a planning system, and a navigation system. We have developed a stereovision localization device (RONNAstereo) that can be attached to the robot end effector for accurate non-contact localization of the patient in the operating room. RONNAstereo has two infrared (IR) cameras with macro lenses aligned at a 55° angle in the same plane. We have evaluated the application accuracy of the RONNA G3 system in a phantom study with two different registration methods. The first registration method involves a rigid fiducial marker with four retroreflective spheres (spherical fiducials). The second method uses freely distributed individual spherical fiducials mounted on single bone screws. We have evaluated the RONNA G3 positioning error for superficial (< 50 mm) and deep (50 mm to 120 mm) targets. The mean target positioning error (TPE) of the RONNA G3 system for superficial and deep targets was 0.43 mm (interquartile range 0.22 mm to 0.60 mm) and 0.88 mm (interquartile range 0.66 mm to 1.10 mm), respectively. Given the positioning errors from the phantom trials, we have prepared the system for clinical trials, which are currently in progress.
Authors: Švaco, M.; Šekoranja, B.; Šuligoj, F.; Vidaković, J.; Jerbić, B.; Chudy, D.
Journal: Strojniški vestnik - Journal of Mechanical Engineering
Year: 2017
Link to the Paper : https://doi.org/10.5545/sv-jme.2017.4649
Automated Marker Localization in the Planning Phase of Robotic Neurosurgery
Accurate patient registration is a critical issue in medical image-guided interventions.
The neurosurgical robotic system RObotic Neuro-NAvigation (RONNA) uses four retro-reflective spheres, on a marker attached to the patient's cranial bone, for patient registration in physical and image space. In this paper, the algorithm for automatic localization of spherical fiducials in CT scans is presented and clinically evaluated. The developed localization algorithm uses a unique approach, which combines machine vision algorithms, biomedical image filtration methods, and mathematical estimation methods. The performance of the localization algorithm was evaluated in comparison with four skilled human operators. The measurements were based on twelve patient and eight lab phantom CT scans. The localization error of the algorithm in comparison with the human readings was smaller by 49.29% according to the ground truth estimation and by 45.91% according to the intra-modal estimation. Localization processing time was reduced by 84.96%. Reliability in terms of successful localization of the fiducial marker was 100% for 20 different test samples containing a total of 116 spherical fiducials. Based on the tests carried out in clinical conditions, the localization algorithm has demonstrated reliability with a high degree of accuracy and short processing time. The developed algorithm provides fully automated and accurate machine vision-based patient localization for the neurosurgical clinical application of the robotic system RONNA.
Authors: Šuligoj, F.; Švaco, M.; Jerbić, B.; Šekoranja, B.; Vidaković, J.
Journal: IEEE Access
Year: 2017, 5, 12265–12274
Link to the Paper : https://doi.org/10.1109/ACCESS.2017.2718621
Robotic Application in Neurosurgery Using Intelligent Visual and Haptic Interaction
Today, the complexity and high technical requirements of neurosurgical operations are so demanding
that modern robotic achievements and advances of accompanied technologies appear as the immanent means, which can significantly improve neurosurgical practice. A novel robotic system (RONNA - RObotic NeuroNAvigation) for application in neurosurgery is presented. The RONNA consists of two conventional articulated robot arms with a total of 13 degrees of freedom.
A rigid and accurate robot is used for precise targeting of planned operating points and a compliant robot is used as operative assistant. A distinctive marker was developed for the purpose of precise localization and registration of the patients head. A novel calibration method is presented. The developed dual arm neurosurgical system enables flexible and reliable application with embedded behaviour based control providing intuitive interaction with surgical team and new possibilities compared to the existing surgical robot solutions.
Authors: Jerbić, B.; Nikolić, G.; Chudy, D.; Švaco, M.; Šekoranja, B.
Journal: International Journal of Simulation Modelling
Year: 2015, 14 (1), 71–84
Link to the Paper : https://doi.org/10.2507/IJSIMM14(1)7.290
Book Chapters
Delve deeper into the clinical application of our system by exploring book chapters that provide comprehensive insights into specific medical domains and their integration with our technology.
RONNA G4—Robotic Neuronavigation: A Novel Robotic Navigation Device for Stereotactic Neurosurgery
RONNA G4 (RONNA) is a robotic neuronavigation system based on articulated robotic arms
and is intended for minimal invasive stereotactic procedures such as biopsies, stereoelectroencephalography, epilepsy surgeries, deep brain stimulation, and tumor resections. RONNA can be configured as a single- or dual-arm system: the single-arm system is intended for stereotactic neuronavigation and serves as a navigation assistant to the surgeon, while the dual-arm configuration performs autonomous invasive operation tasks such as bone drilling, probe or needle insertion, etc. RONNA is characterized by a fully automated patient registration procedure, robot position planning, accurate instrument guidance, and autonomous bone drilling. A novel localization method was developed combining machine vision and mathematical estimation, as well as a novel point-pairing correspondence algorithm and a multiobjective cost function for the optimization of robot placement. RONNA provides surgical tool positioning within the patient intracranial space, robotic assistance in drilling operations, and others which are distinguished by extraordinary accuracy in comparison to existing robotic and other neuronavigation systems. The clinical application of RONNA in stereotactic neurosurgical procedures shortens the operation time, lowers procedure invasiveness, enables faster patient recovery, and better utilization of hospital operational resources. Starting from 2016, RONNA has been undergoing clinical trials at the University Hospital Dubrava.
Authors: Jerbić, B.; Švaco, M.; Chudy, D.; Šekoranja, B.; Šuligoj, F.; Vidaković, J.; Dlaka, D.; Vitez, N.; Župančić, I.; Drobilo, L.; Turković, M.; Žgaljić, A.; Kajtazi, M.; Stiperski, I. .
Journal: Elsevier
Year: 2020; pp 599–625.
Link to the Paper : https://doi.org/10.1016/B978-0-12-814245-5.00035-9
Conference Papers
The latest research findings and advancements related to the clinical application of our system through conference papers. These papers offer valuable insights from leading experts in the field.
Agilus Robots for Application in Neurosurgery
In this paper, we verify three different 6 degrees of freedom Kuka Agilus robots for application in neurosurgery.
Application specific reachability maps are generated for robots with 707 mm (R700), 901 mm (R900), and 1101 mm (R1100) horizontal reach. The reachability of each robot reflects a working volume of a standard stereotactic frame which utilizes the center of arc principle. A working volume with 100% reachability yield has been identified for the R900 and R1100 robots when the robot is positioned sideways to the patient. The R700 robot doesn’t have a 100% reachability yield work volume. Robot configurations within the reachability map are further optimized given two dexterity performance indices: the condition number and a new fuzzy joint limit avoidance function. In the experiments, we have further evaluated the impact on robot work volume given robot orientation with respect to the patient. After reorienting the robot a significant increase in work volume with 100% reachability yield was obtained for all three robots.
Authors: Švaco, M.; Koren, P.; Jerbić, B.; Vidaković, J.; Šekoranja, B.; Šuligoj, F.
Journal: Ferraresi, C., Quaglia, G., Eds.; Springer International Publishing: Torino, Italy,
Year: 2017; Vol. 49, pp 996–1006.
Link to the Paper : https://doi.org/10.1007/978-3-319-61276-8_107
Simulation for Robotic Stereotactic Neurosurgery
Through the development of different research and commercial systems, robotic neurosurgery slowly becomes more standard in the medical field.
Beyond other advantages, the possibility of frameless neurosurgery is an important reason for their consideration. However, the use of robots in these applications brings problems regarding robot-patient positioning and possible influence of kinematic restrictions during the execution of a surgical plan. To cope with these, a simulation concept for the control of critical positioning and kinematic parameters is presented in this paper. An optical tracking system, simulation software and stereotactic planning mechanism are integrated into one functional unit. It is a simulation tool which is intended to be used shortly after the operation scene is set in the operating room to ensure seamless operation flow. The system is successfully implemented and evaluated in real clinical use.
Authors: Vidaković, J.; Jerbić, B.; Šuligoj, F.; Švaco, M.; Šekoranja, B.
Journal: DAAAM International Vienna: Mostar, BiH
Year: 2016; pp 266–270
Link to the Paper : https://doi.org/10.2507/27th.daaam.proceedings.083
T-Phantom: A New Phantom Design for Neurosurgical Robotics
In this paper we propose a novel phantom design for measuring application accuracy of neurosurgical robotic systems and stereotactic frames.
We develop a novel phantom (T-Phantom) which enables simultaneous localization of translational displacements in entry and target points. The phantom consists of multiple trajectories positioned around a localizer feature simulating approach trajectories in neurosurgical procedures on the intracranial space. Each trajectory consists of two parallel and coaxial hollow cylinders printed in selective laser sintering technology. We apply a stereo vision measuring method for precise measurements of translational displacements in target and entry positions. The paper further provides a systematic comparison of phantom designs originating from stereotactic frames and neurosurgical robotic systems. To the author’s knowledge, the developed T-Phantom is the first stereotactic phantom which enables simultaneous measurements both in deviation from target and entry positions and angular deviation from the planned trajectory
Authors: Švaco, M.; Jerbić, B.; Stiperski, I.; Dlaka, D.; Vidaković, J.; Šekoranja, B.; Šuligoj, F.
Journal: DAAAM International Vienna: Mostar, BiH
Year: 2016; pp 266–270
Link to the Paper : https://doi.org/DOI:10.2507/27th.daaam.proceedings.039
Medical Applicability of a Low-Cost Industrial Robot Arm Guided with an Optical Tracking System
Robot systems used in surgical procedures can autonomously position tools at points correlated with preoperative imaging techniques such as magnetic resonance (MR) and computed tomography (CT).
The aim of this paper is to measure and assess medical applicability of a low-cost, lightweight industrial robot arm (Universal robot UR5) guided with the medically certified optical tracking system (Polaris Vicra) to positions registered from a CT scan. Technical setup, measurement equipment, device communication and robot control based on OTS feedback are described. Robot intrinsic accuracy, CT scan accuracy and two methods of robot tool positioning with aid of the optical tracking system (OTS) are measured. Measurements show RMS error of the robot (0.669 mm) is decreased 55.4% when guided with OTS using a single marker probe (0.29 mm) and 40.5% when using OTS with relative referencing (0.39 mm). RMS error of the CT scan readings is 0.46 mm.
Authors: Šuligoj, F.; Jerbić, B.; Švaco, M.; Šekoranja, B.; Mihalinec, D.; Vidaković, J.
Journal: 2015 IEEE/RSJ International Conference on; IEEE,
Year: 2015; pp 3785–3790
Link to the Paper : https://doi.org/10.1109/IROS.2015.7353908
Calibration of an Industrial Robot Using a Stereo Vision System
Industrial robots have very good repeatability but still lack good absolute accuracy.
The main reason is difference between the ideal robot kinematic model integrated in the robot controller and actual robot parameters. A method for identifying certain parameters of the robot model has been proposed. A noncontact method using a stereovision system attached to the robot arm is utilized for providing measurements of calibration points in space. Points are represented as spheres which localized by the stereo vision system project a circle in two image capture planes independent of the viewing angle. Spatial coordinates of each sphere center are acquired in different robot configurations. From these readings errors of robot absolute positioning are measured. The standard Denavit-Hartenberg (DH) notation is used when the modified model parameters containing joint encoder offset values are directly input to the robot controller. Calibration experiments carried out on a KUKA KR 6 R900 industrial robot show improved accuracy results. The maximum positioning error around calibration points was decreased from 3.63 mm prior to calibration, to 1.29 mm after the calibration procedure.
Authors: Švaco, M.; Šekoranja, B.; Šuligoj, F.; Jerbić, B.
Journal: In Procedia Engineering
Year: 2014; Vol. 69, pp 459–463.
Link to the Paper : https://doi.org/10.1016/j.proeng.2014.03.012