Navigation Software Research Articles

A Deviate-Based Prioritizing Technique for Regression Testing of Mobile Navigation Service

Mobile navigation service is an important and popular location-based services, which help to recommend routes for mobile users to their destinations. Modern mobile navigation service provides various navigation strategies and considers many complex situations, which make validation and verification of mobile navigation service becomes very difficult. In this paper, we present an approach to prioritize test cases for regression testing of mobile navigation Service. The approach is based on the assumption that there may be a failure if the user's actual route deviates from the navigation recommended route. In this paper, we analyze the mass mobile navigation logs, compare the recommended routes with the user travel routes, identify the deviation of the intersection point, and then priority regression test data by deviation. To evaluate our approach, we conduct a case study on a popular navigation software. By compare proposed prioritizing test approach with random test approach, the approach helps to improve test efficiency.

Flight demonstration of spaceborne real-time angles-only navigation to a noncooperative target in low earth orbit

The paper describes the onboard vision-based navigation software employed during the DLR's AVANTI experiment and presents its flight performance. The navigation task relies on a dedicated target detection module in charge of extracting the line-of-sight observations from the images taken by a monocular camera. The recognition of the target is based on the kinematic identification of its trajectory over a sequence of images. Subsequently, the resulting angles-only measurements are validated dynamically and processed by an Extended Kalman Filter to derive in real-time the relative state estimate. A computationally light implementation of the filter is achieved by the use of an analytical relative motion model. Two autonomous rendezvous to a noncooperative object have been performed in orbit, first from 13 km to 1 km separation, then from 3 km to 50 m. Despite the poor visibility conditions and the strong orbit perturbations encountered at low altitude, the filter was able to supply the onboard guidance and control algorithms with accurate and reliable relative state estimation, enabling thus a safe and smooth approach.

MONTE: the next generation of mission design and navigation software

The Mission analysis, Operations and Navigation Toolkit Environment (MONTE) (Sunseri et al. in NASA Tech Briefs 36(9), 2012) is an astrodynamic toolkit produced by the Mission Design and Navigation Software Group at the Jet Propulsion Laboratory. It provides a single integrated environment for all phases of deep space and Earth orbiting missions. Capabilities include: trajectory optimization and analysis, operational orbit determination, flight path control, and 2D/3D visualization. MONTE is presented to the user as an importable Python language module. This allows a simple but powerful user interface via CLUI or script. In addition, the Python interface allows MONTE to be used seamlessly with other canonical scientific programming tools such as SciPy, NumPy, and Matplotlib. MONTE is the prime operational orbit determination software for all JPL navigated missions.

Improving mapping for Ebola response through mobilising a local community with self-owned smartphones: Tonkolili District, Sierra Leone, January 2015.

BackgroundDuring the 2014–16 Ebola virus disease (EVD) outbreak, the Magburaka Ebola Management Centre (EMC) operated by Médecins Sans Frontières (MSF) in Tonkolili District, Sierra Leone, identified that available district maps lacked up-to-date village information to facilitate timely implementation of EVD control strategies. In January 2015, we undertook a survey in chiefdoms within the MSF EMC catchment area to collect mapping and village data. We explore the feasibility and cost to mobilise a local community for this survey, describe validation against existing mapping sources and use of the data to prioritise areas for interventions, and lessons learned.MethodsWe recruited local people with self-owned Android smartphones installed with open-source survey software (OpenDataKit (ODK)) and open-source navigation software (OpenStreetMap Automated Navigation Directions (OsmAnd)). Surveyors were paired with local motorbike drivers to travel to eligible villages. The collected mapping data were validated by checking for duplication and comparing the village names against a pre-existing village name and location list using a geographic distance and text string-matching algorithm.ResultsThe survey teams gained sufficient familiarity with the ODK and OsmAnd software within 1–2 hours. Nine chiefdoms in Tonkolili District and three in Bombali District were surveyed within two weeks. Following de-duplication, the surveyors collected data from 891 villages with an estimated 127,021 households. The overall survey cost was €3,395; €3.80 per village surveyed. The MSF GIS team (MSF-OCG) created improved maps for the MSF Magburaka EMC team which were used to support surveillance, investigation of suspect EVD cases, hygiene-kit distribution and EVD survivor support. We shared the mapping data with OpenStreetMap, the local Ministry of Health and Sanitation and Sierra Leone District and National Ebola Response Centres.ConclusionsInvolving local community and using accessible technology allowed rapid implementation, at moderate cost, of a survey to collect geographic and essential village information, and creation of updated maps. These methods could be used for future emergencies to facilitate response.

Actionable Analytics for Strategic Maintenance of Critical Software: An Industry Experience Report

NASA has been successfully sustaining the continuous operation of its critical navigation software systems for over 12 years. To accomplish this, NASA scientists must continuously monitor their process, report on current system quality, forecast maintenance effort, and sustain required staffing levels. This report presents some examples of the use of a robust software metrics and analytics program that enables actionable strategic maintenance management of a critical system (Monte) in a timely, economical, and risk-controlled fashion. This article is part of a special issue on Actionable Analytics for Software Engineering.

A novel method to measure mitral valve area in patients with rheumatic mitral stenosis using three-dimensional transesophageal echocardiography: Feasibility and validation.

Neither two- nor three-dimensional (3D) planimetry of the mitral valve (MV) orifice takes the mitral commissures into account. Thus, if the commissures are not completely fused, the MV orifice will not be planar, and MV area (MVA) will be underestimated. The study aimed to validate a novel method for measurement of the MVA using a software that traces the MV orifice including the commissures. The study included 30 patients undergoing percutaneous balloon mitral valvuloplasty for severe rheumatic mitral stenosis. All performed 3D transesophageal echocardiography (TEE) immediately before the procedure. MVA was measured using the mitral valve navigation (MVN) software of the Philips Q-Lab 10.2 in a diastolic frame with maximum diastolic opening of the MV. Regular 3D planimetry of the MV orifice was also performed. Before balloon dilation, the MVA was calculated invasively using the Gorlin's formula. No significant difference was detected between MVN-derived MVA and Gorlin-derived MVA (0.98cm2 vs. 1.0cm2 , P=.33). A statistically significant difference was detected between Planimetry-derived MVA and Gorlin-derived MVA (0.8cm2 vs. 1.0cm2 , P<.001). There were significant linear correlations between MVN-derived MVA and Gorlin-derived MVA (r=.84, P<.001). Using Bland-Altman analysis, Gorlin-derived MVA showed better and relatively narrower limits of agreement with MVN-derived MVA than planimetry-derived MVA. Measurement of the MVA using the MVN method is feasible and is more correlated to the invasively measured MVA than the 3D planimetry method. This is the most accurate method of measuring the MVA that takes MV commissures into account.

Development of Proportional–Integral–Derivative and Fuzzy Control Strategies for Navigation in Agricultural Environments

Farming and agriculture is an area that may benefit from improved use of automation in order to increase working hours and improve food quality and safety. In this paper, a commercial robot was purchased and modified, and crop row navigational software was developed to allow the ground-based robot to autonomously navigate a crop row setting. A proportional–integral–derivative (PID) controller and a fuzzy logic controller were developed to compare the efficacy of each controller based on which controller navigated the crop row more reliably. Results of the testing indicate that both controllers perform well, with some differences depending on the scenario.

Assessment of the Implementation of GNSS into Gliding

Global navigation satellite systems are increasingly part of our lives and many industries including aviation. Glider flying is no exception in this trend. Global navigation satellite systems were part of gliding since the early 1990s. First as official recording devices for simple evidence of sporting performances, then as navigation systems, anti-collision systems and emergency location transmitters. Development of recording application was initiated and supported by International Gliding Commission of World Air Sports Federation in way of certifications for flight recorders. The use of navigation and other modern instruments in gliders has brought many benefits but also risks. However, the advantages outweigh the disadvantages and these systems are now integral part of gliding. With this wide usage of global navigation satellite systems devices, there is great many possibilities how and in which way one can use these systems. Pilots must orient themselves in varied selection of products, which they can use to choose one solution, that fits him. Therefore, to find out how and if pilots use these devices, we created questionnaire survey among 143 Czech glider pilots. We found out, that 84% of them are using global navigation satellite systems devices for official record of flight and for navigation as well. More than half of pilots is using free, not built-in devices. Most common devices are mobile phones up to 5 inches of screen diagonal in combination with approved flight recorder without display. If pilots use mobile device for navigation, 52% of them is using one with Windows Mobile operating system, 33% use Android. Navigational software on these mobile devices is then almost tied between SeeYou Mobile, XCSoar and LK8000. Knowledge about usage preference of global navigation systems devices should help pilots with selection and overall orientation in subject.

How Software Is Changing the Automotive Landscape

A look at the creation and distribution of automotive navigation software at TomTom shows how automotive software has changed and might further change.

Functional Anatomic Computer Engineered Surgery Protocol for the Management of Self-Inflicted Gunshot Wounds to the Maxillofacial Skeleton

Virtual surgical planning (VSP) is an indispensable aid in craniomaxillofacial reconstruction, yet no protocol is established in facial gunshot wounds. We review our experience with computer-aided reconstruction of self-inflicted facial gunshot wounds (SIGSW'S) and propose a protocol for the staged repair. A retrospective case series enrolling patients with SIGSW's managed with the Functional Anatomic Computer Engineered Surgical protocol (FACES) was implemented. Subjects were evaluated at least one month postoperatively. Outcome variables were jaw position, facial projection, oro-nasal communication, lip competence, feeding tube and tracheostomy dependence, descriptive statistics were computed. The FACES protocol implemented during the initial hospitalization is as follows 1) damage control; 2) selective debridement; 3) VSP reconstruction back converted into navigation software 4) navigation assisted midfacial skeletal reconstruction; 5) computer aided oro-mandibular reconstruction with or without microvascular free flaps using custom cutting guides/hardware; 6) navigation assisted, computer aided palatomaxillary reconstruction with or without microvascular free flaps using cutting guides/hardware; 7) navigation assisted reconstruction of the internal orbit; 8) and confirmation of accurate reconstruction using intraoperative CT. The sample was composed of 10 patients, mean age of 43 years (range, 28 - 62 years, 70% M), 100% with SIGSW's to the submental/submandibular region. All had satisfactory facial projection (n=10), nine had satisfactory jaw position, were decannulated by one month's follow up and were feeding tube independent (90%). All traumatic oro-antral communications were closed (n=8, 7 surgical, 1 obturator), seven had adequate lip competence (70%). Complications included fibula malunion (n=1), plate exposure (n=2) infection (n=2), intracranial abscess (n=1) and microstomia (n=2). Computer-aided surgery is an indispensable tool in the reconstruction of SIGSW's. Successfully implemented, it proved to be a useful adjunct for: the restoration of orbital volume, facial projection and symmetry; the inset of composite tissue, and the facilitation of dental implant supported prosthetic rehabilitation.

Augmented 3D venous navigation for neuroendovascular procedures

BackgroundEndovascular venous access is increasingly used for the treatment of many cerebrovascular diseases. The quality of venous roadmapping through arterial injection can be problematic because of contrast media dilution, slow...

Virtual Planning and Allograft Preparation Guided by Navigation for Reconstructive Oncologic Surgery: A Technical Report.

Advanced virtual simulators can be used to accurately detect the best allograft according to size and shape. Obtain a multislice CT scan and a magnetic resonance imaging (MRI) scan preoperatively for each patient; however, if the time between the scans and the surgery is >1 month, consider repeating the MRI because the size of the tumor may have changed during that time. Load DICOM images into a virtual simulation station (Windows 7 Service Pack 1, 64 bit, Intel Core i5/i7 or equivalent) and use mediCAS planning software ( medicas3d.com ) or equivalent (Materialise Mimics or Amira software [FEI]) for image segmentation and virtual simulation with STL (stereolithography) files. Determine and outline the tumor margin on manually fused CT and MRI studies using the registration tool of the mediCAS planning software or equivalent (Materialise Mimics software.). Determine and outline the osteotomies between host and donor using the registration tool of the mediCAS planning software or equivalent (Materialise Mimics software.). Be sure to consider the disintegration of bone tissue that occurs during the osteotomy and corresponds to the thickness of the blade (approximately 1.5 mm). A tool of the mediCAS planning software allows the virtual preoperative planning (STL files) to be transferred to the surgical navigation format, DICOM files. The tumor and allograft are resected using the navigated guidelines, which were previously planned with the virtual platform. The 3D virtual preoperative planning and surgical navigation software are tools designed to increase the accuracy of bone tumor resection and allograft reconstruction3.

Influence of Preoperative Range of Motion on Varus-Valgus Laxity in Total Knee Arthroplasty

In cases of TKA admitting flexion contracture, a treat to acquire soft tissue balance was required attention to the change throughout from full extension to flexion, because preoperative flexion contracture influenced on varus-valgus laxity after TKA at not only extended but also flexed knee position. Total knee arthroplasty (TKA) is one of the excellent treatments for osteoarthritis (OA) of knee. However varus and valgus stability of knee joint after TKA is important factor to improve patients’ quality of life, it remains unclear that what factors influence on varus-valgus laxity. It is assumed that there are many factors concerned with varus-valgus laxity, such as muscle strength, bony alignment, ligament function, implant design, and preoperative range of motion (ROM). In this study, we examined the influence of the flexion contracture on varus-valgus laxity in patients of OA of knee. A total of 42 knees underwent TKA using posterior stabilized (PS) type component by the measured resection method in our hospital were assessed in this study. The mechanical varus-valgus laxity was measured by the navigation system (precision N Knee Navigation Software v4.0; Stryker, Kalamazoo, Michigan) during operation at every 10° throughout the range of movement before and after implanted compornents. The objected knees divided into two groups, one was full extended group and the other was flexion contracture group. We analyzed two groups were compared using a non-parametric Mann-Whitney U test, and pre- and post-TKR comparisons were made using a non-parametric Wilcoxon signed-rank test. Analyses were performed with JMP statistical software v6.0 (SAS Institute, Tokyo, Japan). A p-value < 0.05 was considered to indicate statistical significance. We also evaluated correlation between preoperative ROM and postoperative varus-valgus laxity using the Spearman rank correlation coefficient. There was no significant difference of postoperative varus-valgus laxity between two groups. In the flexion contracture group, postoperative varus-valgus laxity were significantly greater than preoperative one at flexion of 10, 20, 30, 40, 50, and 60 degree. And the changing ratio of varus-valgus laxity in the flexion contracture group, which indicated postoperative varus-valgus laxity per preoperative one, were significantly greater than that in the full extended group at flexion of 80 and 90 degree. There were correlations between preoperative extension angle and changing ratio of varus-valgus laxity at flexion of 10, 20, 30, 60, and 90 degree. The rank correlation coefficient of Spearman were 0.36, 0.33, 0.33, 0.31, and 0.33 (p <0.05) each. In this study, it was observed influence of preoperative ROM on varus-valgus laxity not only at extended knee position but also at flexed knee position in the cases with flexion contracture after TKA. It suggested that treat of soft tissue to improve extension angle is involved varus-valgus laxity at flexed knee position. In cases admitting flexion contracture, a treat to acquire soft tissue balance was required attention to the change throughout from full extension to flexion.

Grid-Based Method for GPS Route Analysis for Retrieval

Grids are commonly used as histograms to process spatial data in order to detect frequent patterns, predict destinations, or to infer popular places. However, they have not been previously used for GPS trajectory similarity searches or retrieval in general. Instead, slower and more complicated algorithms based on individual point-pair comparison have been used. We demonstrate how a grid representation can be used to compute four different route measures: novelty, noteworthiness, similarity, and inclusion. The measures may be used in several applications such as identifying taxi fraud, automatically updating GPS navigation software, optimizing traffic, and identifying commuting patterns. We compare our proposed route similarity measure, C-SIM, to eight popular alternatives including Edit Distance on Real sequence (EDR) and Frechet distance. The proposed measure is simple to implement and we give a fast, linear time algorithm for the task. It works well under noise, changes in sampling rate, and point shifting. We demonstrate that by using the grid, a route similarity ranking can be computed in real-time on the Mopsi2014 1 route dataset, which consists of over 6,000 routes. This ranking is an extension of the most similar route search and contains an ordered list of all similar routes from the database. The real-time search is due to indexing the cell database and comes at the cost of spending 80% more memory space for the index. The methods are implemented inside the Mopsi 2 route module.

StimTrack: An open-source software for manual transcranial magnetic stimulation coil positioning

BackgroundDuring Transcranial Magnetic Stimulation (TMS) experiments researchers often use a neuronavigation system to precisely and accurately maintain coil position and orientation. New methodThis study aimed to develop and validate an open-source software for TMS coil navigation. StimTrack uses an optical tracker and an intuitive user interface to facilitate the maintenance of position and orientation of any type of coil within and between sessions. Additionally, online access to navigation data is provided, hereby adding e.g. the ability to start or stop the magnetic stimulator depending on the distance to target or the variation of the orientation angles. ResultsStimTrack allows repeatable repositioning of the coil within 0.7mm for translation and <1° for rotation. Stimulus-response (SR) curves obtained from 19 healthy volunteers were used to demonstrate that StimTrack can be effectively used in a typical experiment. An excellent intra and inter-session reliability (ICC >0.9) was obtained on all parameters computed on SR curves acquired using StimTrack. Comparison with existing methodStimTrack showed a target accuracy similar to that of a commercial neuronavigation system (BrainSight, Rogue Research Inc.). Indeed, small differences both in position (∼0.2mm) and orientation (<1°) were found between the systems. These differences are negligible given the human error involved in landmarks registration. ConclusionsStimTrack, available as supplementary material, is found to be a good alternative for commercial neuronavigation systems facilitating assessment changes in corticospinal excitability using TMS. StimTrack allows researchers to tailor its functionality to their specific needs, providing added value that benefits experimental procedures and improves data quality.

UNEXMIN: developing an autonomous underwater explorer for flooded mines

The UNEXMIN project (Underwater Explorer for Flooded Mines) is developing an autonomous multi-platform robotic system that can gather geological data whilst exploring and creating 3D maps of flooded underground mines. In 2017, the project consortium is developing software and hardware for autonomous navigation, 3D mapping, and data post-processing tools. The first of three robotic prototypes will be finished by early 2018. Once construction of this prototype is completed, field trials will commence in four flooded underground mines in Europe. The UNEXMIN multi-platform robotic system will be able to retrieve valuable geological and spatial data that cannot be currently obtained.

A new device for fiducial registration of image-guided navigation system for liver RFA.

Radiofrequency ablation for liver tumors (liver RFA) is widely performed under ultrasound guidance. However, discriminating between the tumor and the needle is often difficult because of cavitation caused by RFA-induced coagulation. An unclear ultrasound image can lead to complications and tumor residue. Therefore, image-guided navigation systems based on fiducial registration have been developed. Fiducial points are usually set on a patient's skin. But the use of internal fiducial points can improve the accuracy of navigation. In this study, a new device is introduced to use internal fiducial points using 2D US. 3D Slicer as the navigation software, Polaris Vicra as the position sensor, and two target tumors in a 3D abdominal phantom as puncture targets were used. Also, a new device that makes it possible to obtain tracking coordinates in the body was invented. First, two-dimensional reslice images from the CT images using 3D Slicer were built. A virtual needle was displayed on the two-dimensional reslice image, reflecting the movement of the actual needle after fiducial registration. A phantom experiment using three sets of fiducial point configurations: one conventional case using only surface points, and two cases in which the center of the target tumor was selected as a fiducial point was performed. For each configuration, one surgeon punctured each target tumor ten times under guidance from the 3D Slicer display. Finally, a statistical analysis examining the puncture error was performed. The puncture error for each target tumor decreased significantly when the center of the target tumor was included as one of the fiducial points, compared with when only surface points were used. This study introduces a new device to use internal fiducial points and suggests that the accuracy of image-guided navigation systems for liver RFA can be improved by using the new device.

Direct Anterior Approach Using Navigation Improves Accuracy of Cup Position Compared to Conventional Posterior Approach.

The accuracy of cup position in total hip arthroplasty is essential for a satisfactory result as malpositioning increases the risk of complications including dislocation, high wear rate, loosening, squeaking, edge loading, impingement and ultimately failure.We studied 166 patients in a single-surgeon-series of matched cohorts of patients who underwent total hip arthroplasties. Four separate groups were identified comprising of the posterior approach +/- navigation and the direct anterior approach +/- navigation.We found a significant difference between the direct anterior navigated group and the posterior non-navigated group for both anteversions (P < 0.05, confidence interval (CI) -3.86 to -1.73) and inclination (P < 0.05, CI -3.08 to -1.08). Almost, 72% of anterior navigated patients fell within 5o of the navigation software set target cup position of 45o inclination and 20o anteversion and 100% were within 10o. Only 30% of posterior non-navigated were within 5o of both anteversion and inclination and 73% were within 10o.There was also a significant difference between the direct anterior navigated and non-navigated group with respect to anteversion only (p < 0.05, CI 1.50 to 1.30). There were no other significant differences between approaches +/- navigation.The direct anterior approach allows ease of access to both anterior-superior iliac spines for navigation and a supine patient allows anteversion and inclination to be measured in the frontal plane. We conclude that the direct anterior approach with navigation improves the accuracy of cup position compared to the conventional posterior approach without navigation.

Shoulder hemiarthroplasty assisted by individualized navigation templates 3D printed

Objective To investigate the efficacy and accuracy of 3D printing individualized navi-gation templates used in shoulder hemi-arthroplasty (HA). Methods We collected 9 adult cadaveric specimens of 18 shoulders with no obvious deformities or defects. After CT scanning was conducted on bilateral shoulders, the raw CT data in DICOM format were imported into software Mimics 10.01 and Imageware 12.0 to reconstruct 3D shoulder models. The retroversion angles and heights of bilateral humeral heads were mea-sured to design individualized navigational templates using software Geomagic Studio 12.0. Rapid prototyping (RP) technique was used to manufacture the individualized navigation templates which were then used to assist shoulder HA in cadaveric specimens. CT scanning was performed postoperatively to measure the retroversion angle and height of the prosthesis implanted for comparison with the preoperative measurements. Results Before shoulder replacement in the 9 cadaveric specimens, respectively, the heights of left and right humeral heads averaged 300.0±11.6 mm and 300.0±11.4 mm, and the retroversion angles 15.6°±4.9° and 15.9°±4.9°. After the replacement, the heights of left and right humeral heads averaged 300.0±11.3 mm and 300.0±11.7 mm, respectively, and the retroversion angles 15.7°±4.9° and 15.8°±5.2°, respectively. There were no significant differences between the left and right sides in the pre- or post-operative heights or retroversion angles of the humeral head (P >0.05). There were no significant differences either between pre- and post-operation in the heights or retroversion angles of the left and right humeral heads (P >0.05). The mean errors for the preoperative and postoperative heights and retroversion angles of the humeral heads were 1.44±0.96 mm and 0.25°±0.15°, respectively. Conclusion Individualized navigation templates 3D printed can be used to assist effective and accurate shoulder HA because they are designed and manufactured according to accurate measurements of retroversion angles and heights of the humeral heads which are acquired by computer preoperatively. Key words: Computer-aided design; Shoulder; Arthroplasty, replacement; 3D printing technology

Real-time fluoroscopic needle guidance in the interventional radiology suite using navigational software for percutaneous bone biopsies in children.

Navigational software provides real-time fluoroscopic needle guidance for percutaneous procedures in the Interventional Radiology (IR) suite. We describe our experience with navigational software for pediatric percutaneous bone biopsies in the IR suite and compare technical success, diagnostic accuracy, radiation dose and procedure time with that of CT-guided biopsies. Pediatric bone biopsies performed using navigational software (Syngo iGuide, Siemens Healthcare) from 2011 to 2016 were prospectively included and anatomically matched CT-guided bone biopsies from 2008 to 2016 were retrospectively reviewed with institutional review board approval. C-arm CT protocols used for navigational software-assisted cases included institution-developed low-dose (0.1/0.17 μGy/projection), regular-dose (0.36 μGy/projection), or a combination of low-dose/regular-dose protocols. Estimated effective radiation dose and procedure times were compared between software-assisted and CT-guided biopsies. Twenty-six patients (15 male; mean age: 10years) underwent software-assisted biopsies (15 pelvic, 7 lumbar and 4 lower extremity) and 33 patients (13 male; mean age: 9years) underwent CT-guided biopsies (22 pelvic, 7 lumbar and 4 lower extremity). Both modality biopsies resulted in a 100% technical success rate. Twenty-five of 26 (96%) software-assisted and 29/33 (88%) CT-guided biopsies were diagnostic. Overall, the effective radiation dose was significantly lower in software-assisted than CT-guided cases (3.0±3.4 vs. 6.6±7.7mSv, P=0.02). The effective dose difference was most dramatic in software-assisted cases using low-dose C-arm CT (1.2±1.8 vs. 6.6±7.7mSv, P=0.001) or combined low-dose/regular-dose C-arm CT (1.9±2.4 vs. 6.6±7.7mSv, P=0.04), whereas effective dose was comparable in software-assisted cases using regular-dose C-arm CT (6.0±3.5 vs. 6.6±7.7mSv, P=0.7). Mean procedure time was significantly lower for software-assisted cases (91±54 vs. 141±68min, P=0.005). In our experience, navigational software technology in the IR suite is a promising alternative to CT guidance for pediatric bone biopsies providing comparable technical success and diagnostic accuracy with lower radiation dose and procedure time, in addition to providing real-time fluoroscopic needle guidance.