@article{GrunzPennigFieberetal.2021,
  author    = {Grunz, Jan-Peter and Pennig, Lenhard and Fieber, Tabea and Gietzen, Carsten Herbert and Heidenreich, Julius Frederik and Huflage, Henner and Gruschwitz, Philipp and Kuhl, Philipp Josef and Petritsch, Bernhard and Kosmala, Aleksander and Bley, Thorsten Alexander and Gassenmaier, Tobias},
  title     = {Twin robotic x-ray system in small bone and joint trauma: Impact of cone-beam computed tomography on treatment decisions},
  series = {European Radiology},
  volume    = {31},
  journal   = {European Radiology},
  issn      = {0938-7994},
  doi       = {10.1007/s00330-020-07563-5},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235233},
  pages     = {3600-3609},
  year      = {2021},
  abstract  = {Objectives Trauma evaluation of extremities can be challenging in conventional radiography. A multi-use x-ray system with cone-beam CT (CBCT) option facilitates ancillary 3-D imaging without repositioning. We assessed the clinical value of CBCT scans by analyzing the influence of additional findings on therapy. Methods Ninety-two patients underwent radiography and subsequent CBCT imaging with the twin robotic scanner (76 wrist/hand/finger and 16 ankle/foot/toe trauma scans). Reports by on-call radiologists before and after CBCT were compared regarding fracture detection, joint affliction, comminuted injuries, and diagnostic confidence. An orthopedic surgeon recommended therapy based on reported findings. Surgical reports (N = 52) and clinical follow-up (N = 85) were used as reference standard. Results CBCT detected more fractures (83/64 of 85), joint involvements (69/53 of 71), and multi-fragment situations (68/50 of 70) than radiography (all p < 0.001). Six fractures suspected in radiographs were ruled out by CBCT. Treatment changes based on additional information from CBCT were recommended in 29 patients (31.5\%). While agreement between advised therapy before CBCT and actual treatment was moderate (κ = 0.41 [95\% confidence interval 0.35-0.47]; p < 0.001), agreement after CBCT was almost perfect (κ = 0.88 [0.83-0.93]; p < 0.001). Diagnostic confidence increased considerably for CBCT studies (p < 0.001). Median effective dose for CBCT was 4.3 μSv [3.3-5.3 μSv] compared to 0.2 μSv [0.1-0.2 μSv] for radiography. Conclusions CBCT provides advantages for the evaluation of acute small bone and joint trauma by detecting and excluding extremity fractures and fracture-related findings more reliably than radiographs. Additional findings induced therapy change in one third of patients, suggesting substantial clinical impact.},
  language  = {en}
}
@article{ReichelHerzelTabbakhetal.2021,
  author    = {Reichel, Thomas and Herz, Stefan and el Tabbakh, Mohammed and Bley, Thorsten Alexander and Plumhoff, Piet and Rueckl, Kilian},
  title     = {Less than 9.5-mm coracohumeral distance on axial magnetic resonance imaging scans predicts for subscapularis tear},
  series = {JSES International},
  volume    = {5},
  journal   = {JSES International},
  number    = {3},
  doi       = {10.1016/j.jseint.2021.01.014},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259118},
  pages     = {424-429},
  year      = {2021},
  abstract  = {Background Diagnosis of subscapularis (SSC) tendon lesions on magnetic resonance imaging (MRI) can be challenging. A small coracohumeral distance (CHD) has been associated with SSC tears. This study was designed to define a specific threshold value for CHD to predict SSC tears on axial MRI scans. Methods This retrospective study included 172 shoulders of 168 patients who underwent arthroscopic surgery for rotator cuff tear or glenohumeral instability. Diagnostic arthroscopy confirmed an SSC tear in 62 cases (36.0\%, test group a), rotator cuff tear tears other than SSC in 71 cases (41.3\%, control group b) and glenohumeral instability without any rotator cuff tear in 39 cases (22.7\%, zero-sample group c). All patients had a preoperative MRI of the shoulder (1.5T or 3T). Minimum CHD was measured on axial fat-suppressed proton density-, T2-, or T1-weigthed sequences. Receiver operating characteristics analysis was used to determine the threshold value for CHD, and sensitivity and specificity were calculated. Results CHD measurement had a good interobserver reliability (Intraclass correlation coefficient 0.799). Mean CHD was highly significantly (P < .001) less for test group a (mean 7.3 mm, standard deviation ± 2.2) compared with control group b (mean 11.1 mm, standard deviation ± 2.3) or zero-sample group c (mean 13.6 mm, standard deviation ± 2.9). A threshold value of CHD <9.5 mm had a sensitivity of 83.6\% and a specificity of 83.9\% to predict SSC tears. Conclusion A CHD <9.5 mm on MRI is predictive of SSC lesions and a valuable tool to diagnose SSC tears.},
  language  = {en}
}
@article{LuetkensErguenHuflageetal.2021,
  author    = {Luetkens, Karsten Sebastian and Erg{\"u}n, S{\"u}leyman and Huflage, Henner and Kunz, Andreas Steven and Gietzen, Carsten Herbert and Conrads, Nora and Pennig, Lenhard and Goertz, Lukas and Bley, Thorsten Alexander and Gassenmaier, Tobias and Grunz, Jan-Peter},
  title     = {Dose reduction potential in cone-beam CT imaging of upper extremity joints with a twin robotic x-ray system},
  series = {Scientific Reports},
  volume    = {11},
  journal   = {Scientific Reports},
  number    = {1},
  doi       = {10.1038/s41598-021-99748-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-270429},
  year      = {2021},
  abstract  = {Cone-beam computed tomography is a powerful tool for 3D imaging of the appendicular skeleton, facilitating detailed visualization of bone microarchitecture. This study evaluated various combinations of acquisition and reconstruction parameters for the cone-beam CT mode of a twin robotic x-ray system in cadaveric wrist and elbow scans, aiming to define the best possible trade-off between image quality and radiation dose. Images were acquired with different combinations of tube voltage and tube current-time product, resulting in five scan protocols with varying volume CT dose indices: full-dose (FD; 17.4 mGy), low-dose (LD; 4.5 mGy), ultra-low-dose (ULD; 1.15 mGy), modulated low-dose (mLD; 0.6 mGy) and modulated ultra-low-dose (mULD; 0.29 mGy). Each set of projection data was reconstructed with three convolution kernels (very sharp [Ur77], sharp [Br69], intermediate [Br62]). Five radiologists subjectively assessed the image quality of cortical bone, cancellous bone and soft tissue using seven-point scales. Irrespective of the reconstruction kernel, overall image quality of every FD, LD and ULD scan was deemed suitable for diagnostic use in contrast to mLD (very sharp/sharp/intermediate: 60/55/70\%) and mULD (0/3/5\%). Superior depiction of cortical and cancellous bone was achieved in FD\(_{Ur77}\) and LD\(_{Ur77}\) examinations (p < 0.001) with LD\(_{Ur77}\) scans also providing favorable bone visualization compared to FD\(_{Br69}\) and FD\(_{Br62}\) (p < 0.001). Fleiss' kappa was 0.618 (0.594-0.641; p < 0.001), indicating substantial interrater reliability. In this study, we demonstrate that considerable dose reduction can be realized while maintaining diagnostic image quality in upper extremity joint scans with the cone-beam CT mode of a twin robotic x-ray system. Application of sharper convolution kernels for image reconstruction facilitates superior display of bone microarchitecture.},
  language  = {en}
}
@article{HuflageKarstenKunzetal.2021,
  author    = {Huflage, Henner and Karsten, Sebastian and Kunz, Andreas Steven and Conrads, Nora and Jakubietz, Rafael Gregor and Jakubietz, Michael Georg and Pennig, Lenhard and Goertz, Lukas and Bley, Thorsten Alexander and Schmitt, Rainer and Grunz, Jan-Peter},
  title     = {Improved diagnostic accuracy for ulnar-sided TFCC lesions with radial reformation of 3D sequences in wrist MR arthrography},
  series = {European Radiology},
  volume    = {31},
  journal   = {European Radiology},
  number    = {12},
  issn      = {1432-1084},
  doi       = {10.1007/s00330-021-08024-3},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-266512},
  pages     = {9399-9407},
  year      = {2021},
  abstract  = {Objectives Triangular fibrocartilage complex (TFCC) injuries frequently cause ulnar-sided wrist pain and can induce distal radioulnar joint instability. With its complex three-dimensional structure, diagnosis of TFCC lesions remains a challenging task even in MR arthrograms. The aim of this study was to assess the added diagnostic value of radial reformatting of isotropic 3D MRI datasets compared to standard planes after direct arthrography of the wrist. Methods Ninety-three patients underwent wrist MRI after fluoroscopy-guided multi-compartment arthrography. Two radiologists collectively analyzed two datasets of each MR arthrogram for TFCC injuries, with one set containing standard reconstructions of a 3D thin-slice sequence in axial, coronal and sagittal orientation, while the other set comprised an additional radial plane view with the rotating center positioned at the ulnar styloid. Surgical reports (whenever available) or radiological reports combined with clinical follow-up served as a standard of reference. In addition, diagnostic confidence and assessability of the central disc and ulnar-sided insertions were subjectively evaluated. Results Injuries of the articular disc, styloid and foveal ulnar attachment were present in 20 (23.7\%), 10 (10.8\%) and 9 (9.7\%) patients. Additional radial planes increased diagnostic accuracy for lesions of the styloid (0.83 vs. 0.90; p = 0.016) and foveal (0.86 vs. 0.94; p = 0.039) insertion, whereas no improvement was identified for alterations of the central cartilage disc. Readers' confidence (p < 0.001) and assessability of the ulnar-sided insertions (p < 0.001) were superior with ancillary radial reformatting. Conclusions Access to the radial plane view of isotropic 3D sequences in MR arthrography improves diagnostic accuracy and confidence for ulnar-sided TFCC lesions.},
  language  = {en}
}
@article{AugustinWelschBleyetal.2021,
  author    = {Augustin, Anne Marie and Welsch, Stefan and Bley, Thorsten Alexander and Lopau, Kai and Kickuth, Ralph},
  title     = {Color-coded summation images in the evaluation of renal artery stenosis before and after percutaneous transluminal angioplasty},
  series = {BMC Medical Imaging},
  volume    = {21},
  journal   = {BMC Medical Imaging},
  number    = {1},
  doi       = {10.1186/s12880-020-00540-w},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259086},
  pages     = {21},
  year      = {2021},
  abstract  = {Background: Endovascular therapy is the gold standard in patients with hemodynamic relevant renal artery stenosis (RAS) resistant to medical therapy. The severity grading of the stenosis as well as the result assessment after endovascular approach is predominantly based on visible estimations of the anatomic appearance. We aim to investigate the application of color-coded DSA parameters to gain hemodynamic information during endovascular renal artery interventions and for the assessment of the procedures technical success. Methods: We retrospectively evaluated 32 patients who underwent endovascular renal artery revascularization and applied color-coded summation imaging on selected monochromatic DSA images. The differences in time to peak (dTTP) of contrast enhancement in predefined anatomical measuring points were analyzed. Furthermore, differences in systolic blood pressure values (SBP) and serum creatinine were obtained. The value of underlying diabetes mellitus as a predictor for clinical outcome was assessed. Correlation analysis between the patients gender as well as the presence of diabetes mellitus and dTTP was performed. Results: Endovascular revascularization resulted in statistically significant improvement in 4/7 regions of interest. Highly significant improvement of perfusion in terms of shortened TTP values could be found at the segmental artery level and in the intrastenotical segment (p<0.001), significant improvement prestenotical and in the apical renal parenchyma (p<0.05). In the other anatomic regions, differences revealed not to be significant. Differences between SBP and serum creatinine levels before and after the procedure were significant (p=0.004 and 0.0004). Patients ' gender as well as the presence of diabetes mellitus did not reveal to be predictors for the clinical success of the procedure. Furthermore, diabetes and gender did not show relevant correlation with dTTP in the parenchymal measuring points. Conclusions: The supplementary use of color-coding DSA and the data gained from parametric images may provide helpful information in the evaluation of the procedures ' technical success. The segmental artery might be a particularly suitable vascular territory for analyzing differences in blood flow characteristics. Further studies with larger cohorts are needed to further confirm the diagnostic value of this technique.},
  language  = {en}
}