scholarly journals Localization of endovascular tools in X-ray images using a motorized C-arm: visualization on HoloLens

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Yenjung Chen ◽  
Nilay Yatinkumar Shah ◽  
Subhra Sundar Goswami ◽  
Annkristin Lange ◽  
Felix von Haxthausen ◽  
...  

AbstractC-arms are medical devices widely used for image-guided minimally invasive endovascular procedures. This technology requires considerable experience for the physicians to position the C-arm to obtain X-ray images of the endovascular tools. In addition, this image-guided therapy is based on two-dimensional images which lack depth information. The purpose of this study was to develop a system that controls the C-arm movements based on the previous position of the tip of a guide wire and the vessel information, and also displays the estimated tip position (specifically, the virtual line that would join the X-ray source and the projected tip in the flat-panel detector) on an augmented reality device (HoloLens). A phantom study was conducted to evaluate the system using intraoperative cone-beam computed tomography scans to obtain the reference tip position. The mean distance between the tip position (ground truth) and the virtual three-dimensional line was 1.18 mm. The proposed system was able to control the C-arm movements based on the position of the tip of the guide wire. The visualization on HoloLens also allowed a more intuitive understanding of the position of the endovascular tool related to the patient’s anatomy during the intervention.

2021 ◽  
Vol 18 (1) ◽  
pp. 172988142199332
Author(s):  
Xintao Ding ◽  
Boquan Li ◽  
Jinbao Wang

Indoor object detection is a very demanding and important task for robot applications. Object knowledge, such as two-dimensional (2D) shape and depth information, may be helpful for detection. In this article, we focus on region-based convolutional neural network (CNN) detector and propose a geometric property-based Faster R-CNN method (GP-Faster) for indoor object detection. GP-Faster incorporates geometric property in Faster R-CNN to improve the detection performance. In detail, we first use mesh grids that are the intersections of direct and inverse proportion functions to generate appropriate anchors for indoor objects. After the anchors are regressed to the regions of interest produced by a region proposal network (RPN-RoIs), we then use 2D geometric constraints to refine the RPN-RoIs, in which the 2D constraint of every classification is a convex hull region enclosing the width and height coordinates of the ground-truth boxes on the training set. Comparison experiments are implemented on two indoor datasets SUN2012 and NYUv2. Since the depth information is available in NYUv2, we involve depth constraints in GP-Faster and propose 3D geometric property-based Faster R-CNN (DGP-Faster) on NYUv2. The experimental results show that both GP-Faster and DGP-Faster increase the performance of the mean average precision.


2011 ◽  
Vol 18 (4) ◽  
pp. 569-574 ◽  
Author(s):  
Masato Hoshino ◽  
Kentaro Uesugi ◽  
James Pearson ◽  
Takashi Sonobe ◽  
Mikiyasu Shirai ◽  
...  

An X-ray stereo imaging system with synchrotron radiation was developed at BL20B2, SPring-8. A portion of a wide X-ray beam was Bragg-reflected by a silicon crystal to produce an X-ray beam which intersects with the direct X-ray beam. Samples were placed at the intersection point of the two beam paths. X-ray stereo images were recorded simultaneously by a detector with a large field of view placed close to the sample. A three-dimensional wire-frame model of a sample was created from the depth information that was obtained from the lateral positions in the stereo image. X-ray stereo angiography of a mouse femoral region was performed as a demonstration of real-time stereo imaging. Three-dimensional arrangements of the femur and blood vessels were obtained.


2003 ◽  
Vol 99 (3) ◽  
pp. 324-329 ◽  
Author(s):  
Langston T. Holly ◽  
Kevin T. Foley

✓ The authors sought to evaluate the feasibility and accuracy of three-dimensional (3D) fluoroscopic guidance for percutaneous placement of thoracic and lumbar pedicle screws in three cadaveric specimens. After attaching a percutaneous dynamic reference array to the surgical anatomy, an isocentric C-arm fluoroscope was used to obtain images of the region of interest. Light-emitting diodes attached to the C-arm unit were tracked using an electrooptical camera. The image data set was transferred to the image-guided workstation, which performed an automated registration. Using the workstation display, pedicle screw trajectories were planned. An image-guided drill guide was passed through a stab incision, and this was followed by sequential image-guided pedicle drilling, tapping, and screw placement. Pedicle screws of various diameters (range 4–6.5 mm) were placed in all pedicles greater than 4 mm in diameter. Postoperatively, thin-cut computerized tomography scans were obtained to determine the accuracy of screw placement. Eighty-nine (94.7%) of 94 percutaneous screws were placed completely within the cortical pedicle margins, including all 30 lumbar screws (100%) and 59 (92%) of 64 thoracic screws. The mean diameter of all thoracic pedicles was 6 mm (range 2.9–11 mm); the mean diameter of the five pedicles in which wall violations occurred was 4.6 mm (range 4.1–6.3 mm). Two of the violations were less than 2 mm beyond the cortex; the others were between 2 and 3 mm. Coupled with an image guidance system, 3D fluoroscopy allows highly accurate spinal navigation. Results of this study suggest that this technology will facilitate the application of minimally invasive techniques to the field of spine surgery.


Spine ◽  
2004 ◽  
Vol 29 (3) ◽  
pp. 293-297 ◽  
Author(s):  
Everine B. van de Kraats ◽  
Theo van Walsum ◽  
Jorrit-Jan Verlaan ◽  
F. Cumhur Öner ◽  
Max A. Viergever ◽  
...  

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Aobo Zhang ◽  
Qing Han ◽  
Bingpeng Chen ◽  
Chenyu Wang ◽  
Xue Zhao ◽  
...  

Background and purpose. A new method of three-dimensional (3D) reconstruction technology was used to take place of X-ray in measuring valgus correction angle (VCA) of both DDH patients and normal volunteers to improve precision. Two different ways to define VCA according to the various conditions of patients were compared and analyzed. Methods. Bilateral VCA of 50 DDH patients and 56 normal volunteers were measured by Mimics software in the 3D method and X-ray in 2D. Two VCA (the upper VCA and the lower VCA) were measured in both two methods. Every VCA was measured by observer A and observer B for twice separately. The statistical analyses of the differences were calculated among the measurements of the VCA. Results. The mean value of the upper VCA measured in 3D was 4.95°±0.76° in DDH group and 5.56°±0.62° in the normal group with significant difference (t=−6.457, p<0.01). The VCA of DDH group and normal group measured by 3D was larger than 2D, both the upper VCA and the lower VCA. The differences indicated statistically significant. The mean value of lower VCA was 0.60° smaller than the mean value of upper VCA in normal volunteers. The mean value of the lower VCA was 0.58° larger than the mean value of the upper VCA in DDH patients. Conclusions. Compared to X-ray, 3D reconstruction technology is more accurate without conventional limitations. The lower VCA of DDH patients should be regarded as the femoral intramedullary guide angle in TKA, especially for patients with femoral deformities.


1972 ◽  
Vol 50 (1) ◽  
pp. 93-98 ◽  
Author(s):  
F. W. B. Einstein ◽  
K. N. Slessor

The crystal and molecular structure of 3-chloro-3-deoxy-1,2;5,6-di-O-isopropylidene-β-D-idose has been determined from three dimensional X-ray data collected by counter methods. The structure was refined by full-matrix least-squares techniques to a conventional R factor of 5.7% for the 817 observed reflections. The compound crystallizes in the orthorhombic space group P212121 with four molecules in a cell of dimensions a = 9.744(6), b = 26.76(2), c = 5.403(3) Å.The structure analysis has served to confirm the site of halogenation and that it occurs stereospecifically. The conformation of the furan ring is an envelope arrangement with C(4) displaced from the mean plane.


2012 ◽  
Vol 450-451 ◽  
pp. 187-192 ◽  
Author(s):  
Jian De Han ◽  
Wei Sun ◽  
Gang Hua Pan

In this study three-dimensional X-ray computed tomography (X-ray CT) is used to investigate the testing results differences of cement paste and mortar before and after drying. It can be found that the mean gray values of paste and mortar before drying are bigger than after drying, and the impact of drying on cement paste is more serious than mortar. In addition, the porosity of non-drying cement paste and mortar is 1.10% and 0.43%, while that of drying cement paste and mortar is 1.55% and 0.70%, respectively. So, the porosity of paste and mortar markedly increases after drying process. The numbers of pores of paste and mortar sharply increase after drying process in particular between 0.01mm3 and 0.1mm3. The impact of drying on smaller pores is more serious than bigger pores.


1980 ◽  
Vol 58 (10) ◽  
pp. 1042-1045 ◽  
Author(s):  
R. L. Parkes ◽  
N. C. Payne ◽  
E. O. Sherman

An air-stable, red, crystalline, N-bonded acetonitrile complex of Os(III), OsCl3(NCCH3)(P(C6H5)3)2, has been prepared and characterized by elemental analysis, magnetic susceptibility, and a single crystal X-ray structure determination. Crystals are monoclinic, space group P21/c, cell dimensions a = 10.029(2), b = 15.233(2), c = 25.246(4) Å, β = 113.65(1)°, and Z = 4. Three dimensional X-ray diffraction intensity data were collected on an automatic four circle diffractometer using Cu radiation. Full-matrix least-squares refinement on F converged at R = 0.038 for 4384 unique observations. The Os atom has a slightly distorted octahedral coordination geometry, with trans phosphine ligands, mean Os—P 2.406(2) Å. The acetonitrile ligand is σ-bonded through the N atom, Os—N 2.038(6) Å. The bond trans to the acetonitrile ligand. Os—Cl(1) 2.364(2) Å, is not significantly different from the mean of the cisOs—Cl bonds, 2.361(2) Å.


2017 ◽  
Vol 10 (4) ◽  
pp. 256-261 ◽  
Author(s):  
Kevin Chan ◽  
Nikolas K. Knowles ◽  
Jean Chaoui ◽  
Louis M. Ferreira ◽  
Gilles Walch ◽  
...  

Background The Walch B3 glenoid is theorized to be a progression of the B2 biconcave pattern. The present study aimed to compare glenoid indices between B2 and B3 patterns. We hypothesized that the B3 pattern would have significantly worse retroversion, inclination and medialization. Methods Computed tomography scans of 50 patients with B2 erosions [mean (SD) age 68 (9) years; 25 male] and 50 patients with B3 erosions [mean (SD) age 72 (8) years; 22 males] were converted into three-dimensional reconstructions. Retroversion, inclination, medialization and humeral head subluxation were compared. Results The data demonstrated no statistically significant differences [mean (SD)] between groups when assessing retroversion: B2 = 21 (8)°, B3 = 24 (7)° ( p = 0.602); glenoid inclination: B2 = 9 (6)°, B3 = 8 (6)° ( p = 0.967); or medialization: B2 = 12 (4) mm, B3 = 14 (4) mm ( p = 0.384). In the B2 group, the mean (SD) humeral head subluxation was 80% (10%) according to the scapular plane and 55% (9%) according to the glenoid plane, which was not statistically different from the B3 group with a mean (SD) humeral head subluxation of 81% (7%) according to the scapular plane ( p = 0.680) and 54% (7%) according to the glenoid plane ( p = 0.292). Conclusions These results demonstrated no significant differences between the B2 and B3 erosion patterns, with respect to the glenoid indicies measured. The aetiology of the B3 glenoid cannot be completely explained by progression of wear in a B2 glenoid.


2013 ◽  
Vol 84 (1) ◽  
pp. 88-95 ◽  
Author(s):  
Joseph Bouserhal ◽  
Nayla Bassil-Nassif ◽  
Alain Tauk ◽  
Leslie Will ◽  
Michel Limme

ABSTRACT Objective: To assess the volumetric changes and the maxillary response of the naso-maxillary complex (NMC) following rapid maxillary expansion (RME). Materials and Methods: Thirty consecutive patients (14 males and 16 females) with a mean age at first observation of 9.5 ± 1.8 years for males and of 11.8 ± 1.7 years for females, presenting a posterior unilateral or bilateral crossbite and requiring RME, were selected for the study. Each patient underwent expansion to correct the transverse occlusal relationships. Computed tomography scans were taken before RME (T1) and at the end of the active expansion phase (T2). Measurements were performed on scanned images. The Kolmogorov-Smirnov test was performed; the mean differences between measurements at T1 and T2 were compared using the t-test (α  =  .05). Results: All volumetric, maxillary, transverse skeletal anterior and posterior variables as well as all dental anterior and posterior linear and angular variables representing the NMC displayed statistically highly significant increases after RME (P &lt; .001). Conclusions: After RME the total volume of the NMC increased by 12%, the nasal volume by 17%, and the maxillary volume by 10.6%. The maxillary and the nasal contributions represented 69.75% and 30.25%, respectively.


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