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Three-Dimensional Constructive Interference in Steady State (3D CISS) Imaging and Clinical Applications in Brain Pathology. Biomedicines 2022; 10:biomedicines10112997. [PMID: 36428564 PMCID: PMC9687637 DOI: 10.3390/biomedicines10112997] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/14/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022] Open
Abstract
Three-dimensional constructive interference in steady state (3D CISS) is a steady-state gradient-echo sequence in magnetic resonance imaging (MRI) that has been used in an increasing number of applications in the study of brain disease in recent years. Owing to the very high spatial resolution, the strong hyperintensity of the cerebrospinal fluid signal and the high contrast-to-noise ratio, 3D CISS can be employed in a wide range of scenarios, ranging from the traditional study of cranial nerves, the ventricular system, the subarachnoid cisterns and related pathology to more recently discussed applications, such as the fundamental role it can assume in the setting of acute ischemic stroke, vascular malformations, infections and several brain tumors. In this review, after briefly summarizing its fundamental physical principles, we examine in detail the various applications of 3D CISS in brain imaging, providing numerous representative cases, so as to help radiologists improve its use in imaging protocols in daily clinical practice.
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Mageed M, Dyab S, Swagemakers JH, Gerlach K. The impact of different bone tracers and acquisition times on image quality of equine bone scintigraphy. Vet Radiol Ultrasound 2022; 63:593-600. [PMID: 35666549 DOI: 10.1111/vru.13107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
The impact of different acquisition times (AqT) and technetium-99 m-labeled (99m Tc) diphosphonates on the image quality of bone scintigraphy is poorly documented in horses. The aim of this prospective experimental study was to evaluate the impact of varying 99m Tc-disphosphonates and AqT on semiquantitative and qualitative image parameters of bone scintigraphy in horses. Twenty-four horses undergoing bone scintigraphy were divided equally and randomly into methylene- (MDP), hydroxymethylene- (HDP), and dicarboxypropane diphosphonate (DPD) groups. Lateral scintigraphic images of the antebrachium were obtained 3 h post 99m TC-diphosphonate injection using three AqT (60, 90, 120 s). The images were analyzed semiquantitatively using the bone-soft tissue ratio (B:ST), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and image contrast. Furthermore, a blinded qualitative analysis was performed using a visual grading analysis. The results showed that DPD images had a significantly higher B:ST ratio than MDP images (P < .01) but not HDP images in all AqT (P > .08). However, DPD and HPD images acquired at 60 s had significantly higher CNR (P < .05) than those acquired at 90 and 120 s. The qualitative analysis revealed no significant differences between 99m Tc-diphosphonates at AqT 60 and 90 s. However, MDP images acquired at 120 s had significantly lower image quality compared to DPD and HDP (P = .01 and .03, respectively). In conclusion, the bone tracers affected the semiquantitative image parameters but not the qualitative analysis findings. Increasing AqT did not necessarily improve the image quality. Therefore, decreasing the AqT enabled a reduction in personnel radiation exposure.
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Affiliation(s)
- Mahmoud Mageed
- Tierklinik Lüsche GmbH, Independent researcher, Bakum, Germany
| | | | | | - Kerstin Gerlach
- Department for Horses, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany
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Hansson J, Månsson LG, Båth M. EVALUATION OF VGC ANALYZER BY COMPARISON WITH GOLD STANDARD ROC SOFTWARE AND ANALYSIS OF SIMULATED VISUAL GRADING DATA. RADIATION PROTECTION DOSIMETRY 2021; 195:378-390. [PMID: 33940628 PMCID: PMC8507457 DOI: 10.1093/rpd/ncab066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 03/09/2021] [Accepted: 04/03/2021] [Indexed: 06/12/2023]
Abstract
The purpose of the present work was to evaluate the use of resampling statistical methods for analysis of visual grading data-implemented in the software VGC Analyzer-by comparing the reanalyzed results from previously performed visual grading studies with the results calculated by gold standard receiver operating characteristic (ROC) methodology, Obuchowski-Rockette (OR)-Dorfman-Berbaum-Metz (DBM) multiple-readers and multiple-case (MRMC) and by analysis of simulated visual grading data where the true distribution was presumed to be known. The reanalysis was performed on two multiple-reader studies with non-paired data and paired data, respectively. The simulation study was performed by simulating a large number of visual grading characteristics (VGC) studies and by analyzing the statistical distribution of null hypothesis (H0) rejection rate. The comparison with OR-DBM MRMC showed good agreement when analyzing non-paired data for both fixed-reader and random-reader settings for the calculated area under the curve values and the confidence intervals (CIs). For paired data analysis, VGC Analyzer showed significantly lower CIs compared with the ROC software. This effect was also illustrated by the simulation study, where the VGC Analyzer, in general, showed good accuracy for simulated studies with stable statistical basis. For simulated studies with unstable statistics, the accuracy in the H0 rejection rate decreased. The present study has shown that resampling methodology can be used to accurately perform the statistical analysis of a VGC study, although the resampling technique used makes the method sensitive to small data sets.
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Affiliation(s)
| | - Lars Gunnar Månsson
- Department of Radiation Physics, Institute of Clinical Sciences, The Sahlgrenska Academy at University of Gothenburg, Gothenburg SE-413 45, Sweden
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg SE-413 45, Sweden
| | - Magnus Båth
- Department of Radiation Physics, Institute of Clinical Sciences, The Sahlgrenska Academy at University of Gothenburg, Gothenburg SE-413 45, Sweden
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg SE-413 45, Sweden
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Clinical utility of deep learning motion correction for T1 weighted MPRAGE MR images. Eur J Radiol 2020; 133:109384. [PMID: 33186856 DOI: 10.1016/j.ejrad.2020.109384] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 10/12/2020] [Accepted: 10/23/2020] [Indexed: 11/23/2022]
Abstract
PURPOSE To evaluate the clinical utility of the application of a deep learning motion correction technique on 3D MPRAGE magnetic resonance images acquired in routine clinical practice. METHODS An encoder-decoder deep learning network inspired by InceptionResnet was trained on public datasets. The clinical utility of the trained network was evaluated retrospectively on 27 3D MPRAGE T1 weighted motion degraded MR images identified by radiologists during reporting. The assessment of image quality was performed by one board-certified radiologist and one senior radiology trainee for nine neuroanatomical regions of the brain using a five-point visual grading scale. RESULTS The deep learning motion correction technique resulted in reduced ghosting, ringing and blurring for all the brain regions investigated. The larger regions of interest such as ventricles improved the least (1.81 to 1.16, p-value: < 0.0001) while the smaller but complex regions such as the hippocampus improved most (3.0 to 1.67, p-value: < 0.0001). The Wilcox rank tests of image quality differences for the nine neuroanatomical regions were all statistically significant (p < 0.001). Overall, 60 % of the neuroanatomical regions were improved, 39 % were unchanged and 1 % were degraded. Out of the unchanged cases, 28 % were already scored at the highest image quality before motion correction. It was found that approximately 13 % of repeated scans could be avoided using the DL motion correction approach. CONCLUSION The deep learning motion correction technique improved the overall visual perception of the 3D T1 weighted MPRAGE brain images. This would improve the clinical utility of otherwise motion degraded images and allow visualisation of normal anatomy and even subtle pathology.
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Mageed M, Wegert J, Dyab S, Gerlach K. Furosemide administration onehour before bone scintigraphy examination in horses does not improve the image quality or reduce the radiation dose rate. Vet Radiol Ultrasound 2020; 62:126-132. [PMID: 33040424 DOI: 10.1111/vru.12917] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 07/24/2020] [Accepted: 07/24/2020] [Indexed: 11/29/2022] Open
Abstract
This prospective, cross-sectional, pilot study aimed to investigate the effects of furosemide as a diuretic on the image quality of bone scintigraphy performed using 99m Tc-HDP and to investigate the impact of furosemide on the radiation dose rate. Thirty-one horses undergoing bone scintigraphy were included. The horses were divided into the control (n = 14) and furosemide group (n = 17), which received 1 mg/kg furosemide intravenously 1 h post 99m Tc-HDP administration. The image quality was assessed subjectively and semi-quantitatively. The bone-to-soft tissue (B:S) ratio was calculated from the counts per pixel of regions of interest (ROI) positioned over the left radial diaphysis (bone ROI) and its caudal soft tissue area (soft tissue ROI). The radiation rate dose (μSv/h) of both groups was measured at 0, 3, 6, 12, 18, and 24 h post 99m Tc-HDP administration at a distance of 0, 30, and 100 cm from the head, kidney, and pelvis. The results showed no significant differences in the B:S ratio or the radiation dose rate observed between the groups. However, the radiation dose rate decreased by 56% at 3 h post 99m Tc-HDP administration and keeping a distance of 30 cm reduced the radiation dose rate by 65%. Administering furosemide does not improve the image quality or reduce the radiation dose rate. The authors recommend commencing with bone scintigraphy 3 h post 99m Tc-HDP administration and keeping at least a distance of 30 cm from the horse to reduce the staff radiation dose.
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Affiliation(s)
- Mahmoud Mageed
- Tierklinik Lüsche GmbH, Tierklinik Lüsche GmbH, Essenerstr. 39a, Bakum, 49456, Germany
| | - Julius Wegert
- Tierklinik Lüsche GmbH, Tierklinik Lüsche GmbH, Essenerstr. 39a, Bakum, 49456, Germany
| | - Shahlaa Dyab
- Tierklinik Lüsche GmbH, Tierklinik Lüsche GmbH, Essenerstr. 39a, Bakum, 49456, Germany
| | - Kerstin Gerlach
- Departement for Horses, University of Leipzig, Leipzig, Germany
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Lisson CG, Lisson CS, Vogele D, Strauss B, Schuetze K, Cintean R, Beer M, Schmidt SA. Improvement of image quality applying iterative scatter correction for grid-less skeletal radiography in trauma room setting. Acta Radiol 2020; 61:768-775. [PMID: 31569948 DOI: 10.1177/0284185119878348] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Iterative reconstruction is well established for CT. Plain radiography also takes advantage of iterative algorithms to reduce scatter radiation and improve image quality. First applications have been described for bedside chest X-ray. A recent experimental approach also provided proof of principle for skeletal imaging. PURPOSE To examine clinical applicability of iterative scatter correction for skeletal imaging in the trauma setting. MATERIAL AND METHODS In this retrospective single-center study, 209 grid-less radiographs were routinely acquired in the trauma room for 12 months, with imaging of the chest (n = 31), knee (n = 111), pelvis (n = 14), shoulder (n = 24), and other regions close to the trunk (n = 29). Radiographs were postprocessed with iterative scatter correction, doubling the number of images. The radiographs were then independently evaluated by three radiologists and three surgeons. A five-step rating scale and visual grading characteristics analysis were used. The area under the VGC curve (AUCVGC) quantified differences in image quality. RESULTS Images with iterative scatter correction were generally rated significantly better (AUCVGC = 0.59, P < 0.01). This included both radiologists (AUCVGC = 0.61, P < 0.01) and surgeons (AUCVGC = 0.56, P < 0.01). The image-improving effect was significant for all body regions; in detail: chest (AUCVGC = 0.64, P < 0.01), knee (AUCVGC = 0.61, P < 0.01), pelvis (AUCVGC = 0.60, P = 0.01), shoulder (AUCVGC = 0.59, P = 0.02), and others close to the trunk (AUCVGC = 0.59, P < 0.01). CONCLUSION Iterative scatter correction improves the image quality of grid-less skeletal radiography in the clinical setting for a wide range of body regions. Therefore, iterative scatter correction may be the future method of choice for free exposure imaging when an anti-scatter grid is omitted due to high risk of tube-detector misalignment.
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Affiliation(s)
- Christoph G Lisson
- Department of Diagnostic and Interventional Radiology, Ulm University Medical Center, Ulm, Germany
| | - Catharina S Lisson
- Department of Diagnostic and Interventional Radiology, Ulm University Medical Center, Ulm, Germany
| | - Daniel Vogele
- Department of Diagnostic and Interventional Radiology, Ulm University Medical Center, Ulm, Germany
| | - Beatrice Strauss
- Department of Orthopedic Trauma, Hand, Plastic and Reconstructive Surgery, Ulm University Medical Center, Ulm, Germany
| | - Konrad Schuetze
- Department of Orthopedic Trauma, Hand, Plastic and Reconstructive Surgery, Ulm University Medical Center, Ulm, Germany
| | - Raffael Cintean
- Department of Orthopedic Trauma, Hand, Plastic and Reconstructive Surgery, Ulm University Medical Center, Ulm, Germany
| | - Meinrad Beer
- Department of Diagnostic and Interventional Radiology, Ulm University Medical Center, Ulm, Germany
| | - Stefan A Schmidt
- Department of Diagnostic and Interventional Radiology, Ulm University Medical Center, Ulm, Germany
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Cristofaro M, Busi Rizzi E, Piselli P, Pianura E, Petrone A, Fusco N, Di Stefano F, Schinina' V. Image quality and radiation dose reduction in chest CT in pulmonary infection. Radiol Med 2020; 125:451-460. [PMID: 32048157 DOI: 10.1007/s11547-020-01139-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 01/16/2020] [Indexed: 12/17/2022]
Abstract
PURPOSE To evaluate the effect of dose reduction with iterative reconstruction (IR) on image quality of chest CT scan comparing two protocols. MATERIALS AND METHODS Fifty-nine patients were enrolled. The two CT protocols were applied using Iterative Reconstruction (ASIR™) 40% but different noise indexes, recording dose-length product (DLP) and volume computed tomography dose index (CTDIvol). The subjective IQ was rated based on the distinction of anatomic details using a 4-point Likert scale based on the European Guidelines on Quality Criteria for CT. For each patient, two single CTs, at enrollment (group 1) and at follow-up after lowering the dose (group 2), were evaluated by two radiologists evaluating, for each examination, five different lung regions (central zone-CZ; peripheral zone-PZ; sub-pleural region-SPR; centrilobular region-CLR; and apical zone-AZ). An inter-observer agreement was expressed by weighted Cohen's kappa statistics (k) and intra-individual differences of subjective image analysis through visual grading characteristic (VGC) analysis. RESULTS An average 50.4% reduction in CTDIvol and 51.5% reduction in DLP delivered were observed using the dose-reduced protocol. An agreement between observers evaluating group 1 CTs was perfect (100%) and moderate to good in group 2 examinations (k-Cohen ranging from 0.56 for PZ and AZ to 0.70 for SPR). In the VGC analysis, image quality ratings were significantly better for group 1 than group 2 scans for all regions (AUCVGC ranging from 0.56 for CZ to 0.62). However, disagreement was limited to a score 4 (excellent)-to-score 3 (good) IQ transition; apart from a single case in PZ, both the observers scored the IQ at follow-up as 2 (sufficient) starting from a score 4 (excellent). CONCLUSION Dose reduction achieved in the follow-up CT scans, although a lower IQ still allows a good diagnostic confidence.
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Affiliation(s)
- Massimo Cristofaro
- Radiology Unit, National Institute for Infectious Diseases "L. Spallanzani" IRCCS, Via Portuense 292, 00149, Rome, Italy
| | - Elisa Busi Rizzi
- Radiology Unit, National Institute for Infectious Diseases "L. Spallanzani" IRCCS, Via Portuense 292, 00149, Rome, Italy
| | - Pierluca Piselli
- Clinical Epidemiology Unit, National Institute for Infectious Diseases "L. Spallanzani" IRCCS, Via Portuense 292, 00149, Rome, Italy.
| | - Elisa Pianura
- Radiology Unit, National Institute for Infectious Diseases "L. Spallanzani" IRCCS, Via Portuense 292, 00149, Rome, Italy
| | - Ada Petrone
- Radiology Unit, National Institute for Infectious Diseases "L. Spallanzani" IRCCS, Via Portuense 292, 00149, Rome, Italy
| | - Nicoletta Fusco
- Radiology Unit, National Institute for Infectious Diseases "L. Spallanzani" IRCCS, Via Portuense 292, 00149, Rome, Italy
| | - Federica Di Stefano
- Radiology Unit, National Institute for Infectious Diseases "L. Spallanzani" IRCCS, Via Portuense 292, 00149, Rome, Italy
| | - Vincenzo Schinina'
- Radiology Unit, National Institute for Infectious Diseases "L. Spallanzani" IRCCS, Via Portuense 292, 00149, Rome, Italy
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Chung MS, Choi YJ, Hwang JY, Yoon DH, Seo KJ, Lee JH, Baek JH. Feasibility of reduced-dose CT of the head and neck with iterative reconstruction: a phantom and prospective clinical study. Acta Radiol 2019; 60:1457-1464. [PMID: 30776905 DOI: 10.1177/0284185119830276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Mi Sun Chung
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Young Jun Choi
- Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Jae-Yeon Hwang
- Department of Radiology, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Gyeonsangnam-do, Republic of Korea
| | - Dok Hyun Yoon
- Department of Oncology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Kyeong Jin Seo
- Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Jeong Hyun Lee
- Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Jung Hwan Baek
- Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea
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Cho S, Choi Y, Chung S, Lee J, Baek J. High-resolution MRI using compressed sensing-sensitivity encoding (CS-SENSE) for patients with suspected neurovascular compression syndrome: comparison with the conventional SENSE parallel acquisition technique. Clin Radiol 2019; 74:817.e9-817.e14. [DOI: 10.1016/j.crad.2019.06.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 06/27/2019] [Indexed: 11/25/2022]
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Lisson CG, Lisson CS, Kleiner S, Regier M, Beer M, Schmidt SA. Iterative scatter correction for grid-less skeletal radiography allows improved image quality equal to an antiscatter grid in adjunct with dose reduction: a visual grading study of 20 body donors. Acta Radiol 2019; 60:735-741. [PMID: 30149748 DOI: 10.1177/0284185118796668] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Iterative scatter correction (ISC) is a new technique applicable to plain radiography; comparable to iterative reconstruction for computed tomography, it promises dose reduction and image quality improvement. ISC for bedside chest X-rays has been applied and evaluated for some time and has recently been commercially offered for plain skeletal radiography. PURPOSE To analyze the potential of ISC for plain skeletal radiography with regard to image quality improvement, dose reduction, and replacement for an antiscatter grid. MATERIAL AND METHODS A total of 385 radiographs with different imaging protocols of the pelvis and cervical spine were acquired from 20 body donors. Radiographs were rated by four radiologists. Ratings were analyzed with visual grading characteristics (VGC) analysis. The area under the VGC curve was used as a measure of difference in image quality. RESULTS Without ISC, the grid-less images were rated significantly worse than their grid-based counterparts (0.389, P = 0.005); adding ISC made image quality equal (0.498; P = 0.963). In grid-less imaging, reduction of dose by 50% led to significant image quality impairment (0.415, P = 0.001); this was fully counterbalanced when ISC was added (0.512; P = 0.588). CONCLUSION ISC for plain skeletal radiography has the ability to replace the antiscatter grid without image quality impairment, to improve image quality in grid-less imaging, and to reduce patient radiation dose by 50% without substantial loss in image quality.
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Affiliation(s)
- Christoph G Lisson
- Department of Diagnostic and Interventional Radiology, University Hospital of Ulm, Ulm, Germany
| | - Catharina S Lisson
- Department of Diagnostic and Interventional Radiology, University Hospital of Ulm, Ulm, Germany
| | - Sebastian Kleiner
- Department of Diagnostic and Interventional Radiology, University Hospital of Ulm, Ulm, Germany
| | - Marc Regier
- Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Meinrad Beer
- Department of Diagnostic and Interventional Radiology, University Hospital of Ulm, Ulm, Germany
| | - Stefan A Schmidt
- Department of Diagnostic and Interventional Radiology, University Hospital of Ulm, Ulm, Germany
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Guzman-Negron JM, Marks BK, Pizarro-Berdichevsky J, Vasavada SP, Goldman HB. Fluoro-urodynamic Image Interpretation Is Not Altered by Using Dilute Intravesical Contrast. Urology 2018; 120:80-85. [PMID: 30016633 DOI: 10.1016/j.urology.2018.05.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 05/24/2018] [Accepted: 05/30/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVE To determine if using one 250 mL bottle of intravesical contrast followed by sterile saline alters interpretation of fluoroscopic images during fluoro-urodynamics. MATERIALS AND METHODS Subjects were randomized to receive 250 mL of intravesical contrast followed by sterile saline until maximal cystometric capacity vs non-dilute intravesical contrast alone during fluoro-urodynamics. Interpreters, blinded to study group, graded images on an ordinal rank scale rating confidence in image interpretation. Primary endpoint was differences in image interpretation between the two groups using visual grading characteristics curves and contrast-to-noise ratios (CNR). Secondary endpoints were obtaining anthropometric data such as body mass index and waist circumference to determine predictors of CNR in a multivariate multiple regression analysis. RESULTS 26 subjects were randomized to receive dilute intravesical contrast and 22 non-dilute contrast; two subjects were unable to complete the study. There was no difference in baseline characteristics between the two groups. Visual grading characteristics demonstrated no difference in readability of the fluoroscopic images between groups and CNR was not statistically different between the two groups. No correlation was identified between CNR and waist circumference or body mass index. CONCLUSION Interpretation of fluoro-urodynamic images and image quality was not altered with using of 250 mL of contrast followed by saline. Expert reviewers did not perceive a difference in their confidence to distinguish between the two groups. Fluoro-urodynamics can be reliably performed using only 250 mL of contrast without compromising the ability to read the fluoroscopic images.
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Affiliation(s)
| | - Brian K Marks
- Glickman Urologic and Kidney Institute, Cleveland Clinic, Cleveland, OH 44194; Center for Urologic Care, Concord Hospital, Concord, NH 03301
| | - Javier Pizarro-Berdichevsky
- Glickman Urologic and Kidney Institute, Cleveland Clinic, Cleveland, OH 44194; Urogynecology Unit, Sotero del Rio Hospital and Division Obstetricia y Ginecologia Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Sandip P Vasavada
- Glickman Urologic and Kidney Institute, Cleveland Clinic, Cleveland, OH 44194
| | - Howard B Goldman
- Glickman Urologic and Kidney Institute, Cleveland Clinic, Cleveland, OH 44194
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Jadidi M, Båth M, Nyrén S. Dependency of image quality on acquisition protocol and image processing in chest tomosynthesis-a visual grading study based on clinical data. Br J Radiol 2018; 91:20170683. [PMID: 29565673 DOI: 10.1259/bjr.20170683] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE To compare the quality of images obtained with two different protocols with different acquisition time and the influence from image post processing in a chest digital tomosynthesis (DTS) system. METHODS 20 patients with suspected lung cancer were imaged with a chest X-ray equipment with tomosynthesis option. Two examination protocols with different acquisition times (6.3 and 12 s) were performed on each patient. Both protocols were presented with two different image post-processing (standard DTS processing and more advanced processing optimised for chest radiography). Thus, 4 series from each patient, altogether 80 series, were presented anonymously and in a random order. Five observers rated the quality of the reconstructed section images according to predefined quality criteria in three different classes. Visual grading characteristics (VGC) was used to analyse the data and the area under the VGC curve (AUCVGC) was used as figure-of-merit. The 12 s protocol and the standard DTS processing were used as references in the analyses. RESULTS The protocol with 6.3 s acquisition time had a statistically significant advantage over the vendor-recommended protocol with 12 s acquisition time for the classes of criteria, Demarcation (AUCVGC = 0.56, p = 0.009) and Disturbance (AUCVGC = 0.58, p < 0.001). A similar value of AUCVGC was found also for the class Structure (definition of bone structures in the spine) (0.56) but it could not be statistically separated from 0.5 (p = 0.21). For the image processing, the VGC analysis showed a small but statistically significant advantage for the standard DTS processing over the more advanced processing for the classes of criteria Demarcation (AUCVGC = 0.45, p = 0.017) and Disturbance (AUCVGC = 0.43, p = 0.005). A similar value of AUCVGC was found also for the class Structure (0.46), but it could not be statistically separated from 0.5 (p = 0.31). CONCLUSION The study indicates that the protocol with 6.3 s acquisition time yields slightly better image quality than the vender-recommended protocol with acquisition time 12 s for several anatomical structures. Furthermore, the standard gradation processing (the vendor-recommended post-processing for DTS), yields to some extent advantage over the gradation processing/multiobjective frequency processing/flexible noise control processing in terms of image quality for all classes of criteria. Advances in knowledge: The study proves that the image quality may be strongly affected by the selection of DTS protocol and that the vendor-recommended protocol may not always be the optimal choice.
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Affiliation(s)
- Masoud Jadidi
- 1 Departments of Clinical Science, Intervention and Technology, Karolinska Institutet , Stockholm , Sweden
| | - Magnus Båth
- 2 Department of Radiation Physics, Sahlgrenska Academy at University of Gothenburg , Gothenburg , Sweden.,3 Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital , Gothenburg , Sweden
| | - Sven Nyrén
- 4 Molecular medicine and surgery, Karolinska intitutet , Stockholm , Sweden.,5 Department of Thoracic radiology, Karolinska University Hospital , Stockholm , Sweden
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Lang H, Neubauer J, Fritz B, Spira EM, Strube J, Langer M, Kotter E. A retrospective, semi-quantitative image quality analysis of cone beam computed tomography (CBCT) and MSCT in the diagnosis of distal radius fractures. Eur Radiol 2016; 26:4551-4561. [PMID: 27003138 DOI: 10.1007/s00330-016-4321-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 02/29/2016] [Accepted: 03/03/2016] [Indexed: 12/19/2022]
Abstract
OBJECTIVE To compare image quality and diagnostic validity of CBCT and MSCT for distal radius fractures. METHODS 35 CBCT and 33 MSCT scans were retrospectively reviewed with a visual grading scale regarding the depiction of cortical bone, trabecular bone, articular surfaces, and soft tissue. The extent and type of artefacts was analyzed. Agreement on AO classification and measurement of cortical disruption and length of the fracture gap was determined. Fracture reduction was evaluated in post-treatment x-rays. Statistical analysis was performed with visual grading characteristics (VGC), chi square tests, and Kendall's coefficient of concordance. RESULTS CBCT performed significantly worse for cortical bone, articular surfaces, and especially soft tissue. Trabecular bone showed no significant difference. Significantly more CBCT images showed artefacts. Physics-based artefacts were the most common. CBCT scans also showed motion artefacts. There was no significant difference in agreement on AO classification. The agreement on measurements was substantial for both modalities. Slightly more fractures that had undergone MSCT imaging showed adequate reduction. CONCLUSION This initial study of an orthopaedic extremity CBCT scanner showed that the image quality of a CBCT scanner remains inferior for most structures at standard settings. Diagnostic validity of both modalities for distal radius fractures seems similar. KEY POINTS • Subjectively, CBCT remains inferior to MSCT in depicting most structures. • Similar diagnostic validity for CBCT and MSCT imaging of distal radius fractures. • CBCT is a possible alternative to MSCT in musculoskeletal imaging. • Visual grading characteristics (VGC) analysis proves useful in analyzing visual grading scales.
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Affiliation(s)
- H Lang
- Department of Radiology, University Medical Center Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
| | - J Neubauer
- Department of Radiology, University Medical Center Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany.
| | - B Fritz
- Department of Radiology, University Medical Center Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
| | - E M Spira
- Department of Radiology, University Medical Center Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
| | - J Strube
- Department of Radiology, University Medical Center Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
| | - M Langer
- Department of Radiology, University Medical Center Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
| | - E Kotter
- Department of Radiology, University Medical Center Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
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Jadidi M, Sundin A, Aspelin P, Båth M, Nyrén S. Evaluation of a new system for chest tomosynthesis: aspects of image quality of different protocols determined using an anthropomorphic phantom. Br J Radiol 2015; 88:20150057. [PMID: 26118300 DOI: 10.1259/bjr.20150057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To compare the image quality obtained with the different protocols in a new chest digital tomosynthesis (DTS) system. METHODS A chest phantom was imaged with chest X-ray equipment with DTS. 10 protocols were used, and for each protocol, nine acquisitions were performed. Four observers visually rated the quality of the reconstructed section images according to pre-defined quality criteria in four different classes. The data were analysed with visual grading characteristics (VGC) analysis, using the vendor-recommended protocol [12-s acquisition time, source-to-image distance (SID) 180 cm] as reference, and the area under the VGC curve (AUCVGC) was determined for each protocol and class of criteria. RESULTS Protocols with a smaller swing angle resulted in a lower image quality for the classes of criteria "disturbance" and "homogeneity in nodule" but a higher image quality for the class "structure". The class "demarcation" showed little dependency on the swing angle. All protocols but one (6.3 s, SID 130 cm) obtained an AUCVGC significantly <0.5 (indicating lower quality than reference) for at least one class of criteria. CONCLUSION The study indicates that the DTS protocol with 6.3 s yields image quality similar to that obtained with the vendor-recommended protocol (12 s) but with the clinically important advantage for patients with respiratory impairment of a shorter acquisition time. ADVANCES IN KNOWLEDGE The study demonstrates that the image quality may be strongly affected by the choice of protocol and that the vendor-recommended protocol may not be optimal.
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Affiliation(s)
- M Jadidi
- 1 Departments of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
| | - A Sundin
- 2 Radiology Department, Uppsala University Hospital, Uppsala, Sweden.,3 Radiology, Oncology and Radiation Science, Uppsala University, Uppsala, Sweden
| | - P Aspelin
- 4 Departments of Clinical Science, Intervention and Technology, Karolinska University Hospital, Stockholm, Sweden.,5 Radiology Department, Karolinska University Hospital, Stockholm, Sweden
| | - M Båth
- 6 Department of Radiation Physics, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,7 Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - S Nyrén
- 8 Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.,9 Radiology Department, Karolinska Institute, Stockholm, Sweden
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Behrens CF, Andreasen TB, Lindberg H, Buhl SK, Vestergaard A, Elstrøm UV, Sjöström D. Quantitative image quality evaluation of pelvic computed tomography-based imaging systems: a novel concept in radiotherapy. Acta Oncol 2013; 52:1579-82. [PMID: 24024695 DOI: 10.3109/0284186x.2013.818252] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Claus F Behrens
- Herlev Hospital, University of Copenhagen, Department of Oncology , Herlev , Denmark
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Burmeister HP, Bitter T, Heiler PM, Irintchev A, Fröber R, Dietzel M, Baltzer PA, Schad LR, Reichenbach JR, Gudziol H, Guntinas-Lichius O, Kaiser WA. Imaging of lamination patterns of the adult human olfactory bulb and tract: In vitro comparison of standard- and high-resolution 3T MRI, and MR microscopy at 9.4T. Neuroimage 2012; 60:1662-70. [DOI: 10.1016/j.neuroimage.2012.01.101] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 01/14/2012] [Accepted: 01/18/2012] [Indexed: 01/19/2023] Open
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In vitro comparison of water displacement method and 3 Tesla MRI for MR-volumetry of the olfactory bulb: which sequence is appropriate? Acad Radiol 2011; 18:1233-40. [PMID: 21782479 DOI: 10.1016/j.acra.2011.06.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Revised: 06/24/2011] [Accepted: 06/27/2011] [Indexed: 11/21/2022]
Abstract
RATIONALE AND OBJECTIVES Magnetic resonance imaging olfactory bulb (OB) volumetry (OBV) is already used as a complementary prognostic tool to assess olfactory disorders. However, a reference standard in imaging for OBV has not been established. The aim of this in vitro study was to compare volumetric results of different magnetic resonance sequences for OBV at 3 T to genuine OB volumes measured by water displacement. MATERIALS AND METHODS The volumes of 15 human cadaveric OBs were measured using the water displacement method in this institutional review board-approved prospective study. The magnetic resonance imaging protocol at 3 T included constructive interference in steady state (CISS), T2-weighted (T2w) three-dimensional (3D) sampling perfection with application-optimized contrasts using different flip-angle evolutions (SPACE), T2w two-dimensional (2D) turbo spin-echo (TSE), and T1-weighted (T1w) 3D fast low-angle shot (FLASH) sequences. Two blinded observers independently performed two OB volumetric assessments per bulbus and sequence. Intraobserver and interobserver reliabilities were assessed by intraclass correlation coefficients. Bland-Altman plots were analyzed to evaluate systematic biases and concordance correlation coefficients to assess reproducibility. RESULTS For both observers, intraclass correlation coefficient analysis yielded almost perfect results for intraobserver reliability (CISS, 0.94-0.98; T2w 3D SPACE, 0.93-0.98; T2w 2D TSE, 0.98-0.98; T1w 3D FLASH, 0.95-0.99). Interobserver reliability showed almost perfect agreement for all sequences (CISS, 0.98; T2w 3D SPACE, 0.89; T2w 2D TSE, 0.93; T1w 3D FLASH, 0.97). The CISS sequence yielded the highest mean concordance correlation coefficient (0.95) and the highest combination of precision (0.97) and accuracy (0.98) values. In comparison with the water displacement method, Bland-Altman analyses revealed the lowest systematic bias (-0.5%) for the CISS sequence, followed by T1w 3D FLASH (-1.3%), T2w 3D SPACE (-7.5%), and T2w 2D TSE (-10.9%) sequences. CONCLUSIONS Compared to the water displacement method, the CISS sequence is suited best to validly and reliably measure OB volumes because of its highest values for accuracy and precision and lowest systematic bias.
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Burmeister HP, Baltzer PAT, Möslein C, Bitter T, Gudziol H, Dietzel M, Guntinas-Lichius O, Kaiser WA. Reproducibility and repeatability of volumetric measurements for olfactory bulb volumetry: which method is appropriate? An update using 3 Tesla MRI. Acad Radiol 2011; 18:842-9. [PMID: 21669350 DOI: 10.1016/j.acra.2011.02.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 02/05/2011] [Accepted: 02/25/2011] [Indexed: 10/18/2022]
Abstract
RATIONALE AND OBJECTIVES The aim of this study was to compare different sequences for olfactory bulb volumetry using 3-T magnetic resonance imaging, evaluating reproducibility, repeatability, and systematic biases. MATERIALS AND METHODS Twenty-two volunteers underwent 3-T magnetic resonance imaging of the frontal skull base in this prospective study. Imaging included constructive interference in steady state (CISS), T2-weighted (T2w) three-dimensional (3D) sampling perfection with application-optimized contrasts using different flip-angle evolutions, and T2w two-dimensional (2D) turbo spin-echo sequences. Two observers independently performed two olfactory bulb volumetric studies per bulb and sequence. Intraobserver and interobserver reliability was assessed using intraclass correlation coefficients. For the evaluation of reproducibility, concordance correlation coefficients were determined, and for repeatability and systematic biases, Bland-Altman plots were analyzed. RESULTS Intraclass correlation coefficient analysis of the specialized observer yielded almost perfect results for intraobserver reliability (0.94, 0.85, and 0.93 for the CISS, T2w 3D, and T2w 2D sequences, respectively). For the less experienced observer, the results were 0.86 0.78, and 0.74 for the CISS, T2w 3D, and T2w 2D sequences, respectively. Interobserver reliability showed almost perfect agreement for all sequences (0.92, 0.86, and 0.86, respectively). The CISS sequence yielded the highest concordance correlation coefficient (0.84), precision (0.85), and accuracy (0.99). Bland-Altman plot analyses revealed the lowest repeatability coefficients for the T2w 2D sequence. Volumetric measurements of T2w 2D imaging showed systematically lower volumetric results compared to the CISS sequence (-22.7%) and the T2w 3D sequence (-8.3%). CONCLUSIONS Comparison of three imaging sequences for olfactory bulb volumetry yielded the best values for the CISS sequence in terms of intraobserver and interobserver reliability, reproducibility, accuracy, and precision. Given that even less experienced observers achieve almost perfect results, the CISS sequence is recommended for olfactory bulb volumetry.
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