Kooperativer Bibliotheksverbund

Language: English

In: Radiology, September 2018, Vol.288(3), pp.901-908

Description: History A 65-year-old woman presented to her primary care physician with a history of progressive abdominal pain mainly in the upper quadrants, nausea, and edema in the bilateral symmetric lower extremities. Other symptoms and use of medication or related drugs were denied. Physical examination findings were normal. The serum lactate dehydrogenase level was 302 U/L (5.04 μkat/L) (reference range, 〈247 U/L [4.12 μkat/L]), and all other laboratory data were within normal ranges. Electrocardiography and chest radiography revealed no abnormalities. The patient underwent contrast material-enhanced (100 mL of iomeprol [400 mg iodine per milliliter], Iomeron; Bracco Imaging) CT of the chest, abdomen, and pelvis; dynamic contrast-enhanced (13 mL of gadobenate dimeglumine, Multihance; Bracco Imaging) MRI of the chest and abdomen; and transthoracic echocardiography and cavography for further evaluation.

Keywords: Leiomyosarcoma -- Diagnostic Imaging ; Vascular Neoplasms -- Diagnostic Imaging ; Vena Cava, Inferior -- Diagnostic Imaging

ISSN: 00338419

E-ISSN: 1527-1315

DOI: 10.1148/radiol.2018160821

URL: View this record in MEDLINE/PubMed

Language: English

In: Radiology, May 2018, Vol.287(2), pp.715-718

ISSN: 00338419

E-ISSN: 1527-1315

DOI: 10.1148/radiol.2018160819

URL: View this record in MEDLINE/PubMed

Language: English

In: European radiology, July 2014, Vol.24(7), pp.1725-34

Description: To investigate the impact of automated attenuation-based tube potential selection on image quality and exposure parameters in polytrauma patients undergoing contrast-enhanced thoraco-abdominal CT. One hundred patients were examined on a 16-slice device at 120 kV with 190 ref.mAs and automated mA modulation only. Another 100 patients underwent 128-slice CT with automated mA modulation and topogram-based automated tube potential selection (autokV) at 100, 120 or 140 kV. Volume CT dose index (CTDI(vol)), dose-length product (DLP), body diameters, noise, signal-to-noise ratio (SNR) and subjective image quality were compared. In the autokV group, 100 kV was automatically selected in 82 patients, 120 kV in 12 patients and 140 kV in 6 patients. Patient diameters increased with higher kV settings. The median CTDI(vol) (8.3 vs. 12.4 mGy; -33%) and DLP (594 vs. 909 mGy cm; -35%) in the entire autokV group were significantly lower than in the group with fixed 120 kV (p 〈 0.05 for both). Image quality remained at a constantly high level at any selected kV level. Topogram-based automated selection of the tube potential allows for significant dose savings in thoraco-abdominal trauma CT while image quality remains at a constantly high level. • Automated kV selection in thoraco-abdominal trauma CT results in significant dose savings • Most patients benefit from a 100-kV protocol with relevant DLP reduction • Constantly good image quality is ensured • Image quality benefits from higher kV when arms are positioned downward.

Keywords: Image Processing, Computer-Assisted ; Abdominal Injuries -- Diagnostic Imaging ; Multidetector Computed Tomography -- Instrumentation ; Multiple Trauma -- Diagnostic Imaging ; Thoracic Injuries -- Diagnostic Imaging

ISSN: 09387994

E-ISSN: 1432-1084

DOI: 10.1007/s00330-014-3197-7

URL: View this record in MEDLINE/PubMed

Language: English

In: European radiology, June 2014, Vol.24(6), pp.1211-8

Description: To evaluate image quality and diagnostic accuracy of selective monoenergetic reconstructions of late iodine enhancement (LIE) dual-energy computed tomography (DECT) for imaging of chronic myocardial infarction (CMI). Twenty patients with a history of coronary bypass surgery underwent cardiac LIE-DECT and late gadolinium enhancement (LGE) magnetic resonance imaging (MRI). LIE-DECT images were reconstructed as selective monoenergetic spectral images with photon energies of 40, 60, 80, and 100 keV and the standard linear blending setting (M_0.6). Images were assessed for late enhancement, transmural extent, signal characteristics and subjective image quality. Seventy-nine myocardial segments (23 %) showed LGE. LIE-DECT detected 76 lesions. Images obtained at 80 keV and M_0.6 showed a high signal-to-noise ratio (15.9; 15.1), contrast-to-noise ratio (4.2; 4.0) and sensitivity (94.9 %; 92.4 %) while specificity was identical (99.6 %). Differences between these series were not statistically significant. Transmural extent of LIE was overestimated in both series (80 keV: 40 %; M_0.6: 35 %) in comparison to MRI. However, observers preferred 80 keV in 13/20 cases (65 %, κ = 0.634) over M_0.6 (4/20 cases) regarding subjective image quality. Post-processing of LIE-DECT data with selective monoenergetic reconstructions at 80 keV significantly improves subjective image quality while objective image quality shows no significant difference compared to standard linear blending. Late enhancement dual-energy CT allows for detection of chronic myocardial infarction. Monoenergetic reconstructions at 80 keV significantly improve subjective image quality. 80 keV and standard linear blending reconstructions show no significant differences. Extent of CMI detected with LIE-DECT is overestimated compared with MRI.

Keywords: Iodine ; Image Enhancement -- Methods ; Myocardial Infarction -- Diagnostic Imaging ; Tomography, X-Ray Computed -- Methods

ISSN: 09387994

E-ISSN: 1432-1084

DOI: 10.1007/s00330-014-3126-9

URL: View this record in MEDLINE/PubMed

Language: English

In: European Journal of Radiology, January 2015, Vol.84(1), pp.117-122

Description: To reveal the impact on workflow from introducing a dual-room sliding gantry CT to the trauma room for polytrauma and regularly scheduled in- outpatients with regard to efficiency and degree of capacity utilisation. Time analysis was performed for 30 polytrauma patients each in 2 different trauma room settings, the new trauma room comprising a sliding gantry CT, the old one a stationary single-room CT. Complete trauma room and diagnostic workup times were manually measured and compared for both groups. In a third scenario, the number of CT scans performed with one single sliding gantry CT and the two-room concept was compared to the number of CT scans performed on two separate regular CT units in a 5 days clinical routine sample. Patients demographics and type of CT examinations were comparable for all patient groups. The median time from patient arrival in the trauma room until beginning of CT scanning was 6 min shorter for the sliding gantry CT group (21 vs.15 min). Sliding gantry CT embedded in a two-room solution achieved 252 CT scans in 5 working days, compared to 250 CT scans on two separate regular CT units with the same man power. Sliding gantry CT in the trauma room allows for significant time saving in the diagnostic workup of polytrauma patients and faster resumption of the regular in- outpatient's CT schedule is possible. With the same man power, the dual-room solution is able to generate the same throughput as two separate CT units.

Keywords: Sliding Gantry CT ; Trauma Room ; Polytrauma ; Time ; Workflow Optimisation ; Medicine

ISSN: 0720-048X

E-ISSN: 1872-7727

DOI: 10.1016/j.ejrad.2014.10.013

URL: View record in ScienceDirect (Access to full text may be restricted)

Language: English

In: European Radiology, 2011, Vol.21(9), pp.1914-1921

Description: Byline: Ralf W. Bauer (1), Claudia Frellesen (1), Matthias Renker (1,2), Boris Schell (1), Thomas Lehnert (1), Hanns Ackermann (3), U. Joseph Schoepf (2), Volkmar Jacobi (1), Thomas J. Vogl (1), J. Matthias Kerl (1) Keywords: Dual energy CT; Pulmonary embolism; Blood volume assessment; Clinical outcome; Right heart strain Abstract: Objective To investigate the role of perfusion defect (PD) size on dual energy CT pulmonary blood volume assessment as predictor of right heart strain and patient outcome and its correlation with d-dimer levels in acute pulmonary embolism (PE). Methods 53 patients with acute PE who underwent DECT pulmonary angiography were retrospectively analyzed. Pulmonary PD size caused by PE was measured on DE iodine maps and quantified absolutely (VolPD) and relatively to the total lung volume (RelPD). Signs of right heart strain (RHS) on CT were determined. Information on d-dimer levels and readmission for recurrent onset of PE and death was collected. Results D-dimer level was mildly (r=0.43--0.47) correlated with PD size. Patients with RHS had significantly higher VolPD (215 vs. 73 ml) and RelPD (9.9 vs. 2.9%) than patients without RHS (p〈0.003). There were 2 deaths and 1 readmission due of PE in 18 patients with 〉5% RelPD, while no such events were found for patients with 〈5% RelPD. Conclusion Pulmonary blood volume on DECT in acute PE correlates with RHS and appears to be a predictor of patient outcome in this pilot study. Author Affiliation: (1) Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany (2) Heart&Vascular Center, Ashley River Tower, Medical University of South Carolina, MSC 226, 25 Courtenay Drive, Charleston, SC, 29401, USA (3) Department of Biostatistics and Mathematical Modelling, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany Article History: Registration Date: 21/04/2011 Received Date: 16/11/2010 Accepted Date: 29/03/2011 Online Date: 30/04/2011

Keywords: Dual energy CT ; Pulmonary embolism ; Blood volume assessment ; Clinical outcome ; Right heart strain

ISSN: 0938-7994

E-ISSN: 1432-1084

DOI: 10.1007/s00330-011-2135-1

URL: View full text in Springer (Subscribers only)

Language: English

In: La Radiologia Medica, 2015, Vol.120(12), p.1112(10)

Description: Byline: Julian L. Wichmann (1,3), Xiaohan Hu (1), Alexander Engler (2), J. Matthias Kerl (1), Martin Beeres (1), Claudia Frellesen (1), Wolfgang Luboldt (1), Thomas J. Vogl (1), Ralf W. Bauer (1), Thomas Lehnert (1) Keywords: Coronary computed tomography angiography; Dual-source computed tomography angiography; Multidetector-computed tomography; High-pitch spiral acquisition; Radiation dose Abstract: Objectives To compare radiation exposure and image quality of second-generation 128-slice dual-source CT (DSCT) coronary angiography (cCTA) protocols. Materials and methods We retrospectively analyzed data from four groups with 25 patients, each examined by one of the following DSCT cCTA protocols: prospectively ECG-gated high-pitch (group 1) or sequential (group 2) acquisition, retrospectively ECG-gated acquisition in dual-energy (DECT, group 3) or dual-source (group 4) mode. CT dose index volume, dose length product, estimated radiation dose, contrast-to-noise- and signal-to-noise-ratios were compared. Subjective image quality was rated by two observers blinded to the protocols. Results High-pitch DSCT showed a mean estimated radiation dose of 1.27 [+ or -] 0.62 mSv, significantly (p 〈 0.01) lower than sequential (2.04 [+ or -] 0.94 mSv), dual-energy (3.97 [+ or -] 1.29 mSv) or dual-source (8.11 [+ or -] 4.95 mSv) acquisition. Image noise showed no statistical difference (p 〉 0.91), ranging from 15.2 [+ or -] 4.4 (group 2) up to 24.5 [+ or -] 22.0 (group 4). Each protocol showed diagnostic image quality in at least 98.1 % of evaluated coronary segments without significant differences (p 〉 0.05). Conclusions Prospectively ECG-gated DSCT protocols enable cCTA with significant dose reduction and consistently diagnostic image quality. In patients requiring retrospectively ECG-gated DSCT for functional analysis or due to arrhythmia, dual-energy mode should be preferred over dual-source mode as it significantly decreases estimated dose without compromising image quality. Author Affiliation: (1) Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany (2) Department of Cranio-Maxillofacial and Plastic Facial Surgery, University Hospital Frankfurt, Frankfurt, Germany (3) Universitatsklinikum Frankfurt Am Main, Institut fur Diagnostische Und Interventionelle Radiologie, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany Article History: Registration Date: 28/04/2015 Received Date: 29/01/2015 Accepted Date: 28/04/2015 Online Date: 16/05/2015

Keywords: Arrhythmia ; Angiography ; Electrocardiography ; Cat Scans

ISSN: 0033-8362

Source: Cengage Learning, Inc.

In: Open Journal of Radiology, 2015, Vol.05(02), pp.84-91

Description: Purpose: To investigate a robot assistance device for CT-guided percutan liver biopsy. Materials and Methods: The liver of a corpse was equipped with target dummies. Four radiologists used a 16 G needle to perform biopsy of the target region in standard free hand technique and then used a robot system which allowed planning and aligning the trajectory path. Accuracy in terms of needle tip deviation, and time efficiency and radiation exposure in terms of effective dose for the radiologists were measured. Results: For in plane procedures, there was no significant benefit in accuracy when using the robot versus standard technique (4 mm vs. 5.6 mm, p = 0.11); timely effort was worse (443 sec vs. 405 sec, p = 0.64). For angulated punctures, a needle tip of 3.7 mm was measured by using the robotic device (vs. 10.8 mm, p

Keywords: Medicine;

ISSN: 2164-3024

E-ISSN: 2164-3032

DOI: 10.4236/ojrad.2015.52014

Source: CrossRef

In: Investigative Radiology, 2018, Vol.53(7), pp.409-416

Description: PURPOSE: The aim of this study was to evaluate the diagnostic performance of virtual noncalcium (VNCa) dual-energy computed tomography (DECT) reconstructions enabling visualization of bone marrow edema for characterization of incidental thoracolumbar compression fractures in routine thoracoabdominal staging computed tomography (CT). MATERIALS AND METHODS: We retrospectively analyzed 51 oncological patients without suspected fracture or indicative complaints presenting at least 1 thoracolumbar compression fracture on routine thoracoabdominal staging DECT who had been examined between October 2015 and June 2017 using third-generation dual-source CT, had a previous CT within 3 months before, and also had undergone additional magnetic resonance imaging within 14 days, which served as the standard of reference. Three independent and blinded radiologists initially evaluated all vertebrae on conventional grayscale DECT series; after at least 8 weeks, observers reevaluated all cases using grayscale and color-coded VNCa DECT images. The age of each fracture was determined as either acute, chronic, or inconclusive. Specificity, sensitivity, and intraobserver and interobserver agreements were calculated taking into account clustering. RESULTS: A total of 98 vertebral compression fractures were detected in 51 patients (20 women, 31 men; median of 1 fracture per patient). The reference standard defined 45 as acute and 53 as chronic. For identification of only acute fractures (cutoff 1), the combination of grayscale and VNCa image series showed a higher sensitivity (91% vs 47%; P 〈 0.001) but equal specificity (both 100%) compared with analysis of grayscale images alone. When defining a positive finding as a fracture considered either acute or inconclusive (cutoff 2), combined analysis of grayscale and VNCa images showed similar sensitivity (96% vs 93%; P = 0.28) but significantly higher specificity (96% vs 75%; P 〈 0.001) compared with evaluation of grayscale images alone. Area under the curve analysis for detection of vertebral compression fractures showed superior results for reading of grayscale and VNCa image series (0.98) compared with analysis of grayscale images alone (0.89; P 〈 0.001). CONCLUSION: Dual-energy CT–derived color-coded VNCa reconstructions substantially improve the characterization of incidental thoracolumbar compression fractures seen on routine thoracoabdominal staging DECT by allowing for visualization of bone marrow edema.

Keywords: Cat Scans -- Usage ; Edema -- Care And Treatment;

ISSN: 0020-9996

E-ISSN: 15360210

DOI: 10.1097/RLI.0000000000000458

Language: English

In: European Journal of Radiology, October 2015, Vol.84(10), pp.1910-1914

Description: To investigate the association between aortic root calcification (ARC) and coronary artery calcification (CAC) assessed by coronary artery calcium-scoring dual-source computed tomography (DSCT). We retrospectively analyzed 143 consecutive patients who underwent coronary artery calcium-scoring during coronary DSCT angiography. 57 patients had findings of ARC on calcium-scoring scans. ARC volume (ARCV) and Agatston coronary artery calcium score (CACS) were calculated. Chi-square test was used to assess differences of categorical variables between patients with and without ARC. Statistical significances between both groups were assessed with the independent-Sample test. Compared with patients without ARC ( = 86), patients with ARC ( = 57) showed a significantly higher presence of CAC (87.7% vs. 24.4%; 〈 0.001), and a higher mean CACS (700.6 ± 941.2 vs. 256.4 ± 724.3; = 0.009) in patients with CAC. Patients with a calculated ARCV 〉40 mm ( = 32) showed significantly higher rates of severe CAC (56.3% vs. 24.0%; = 0.014) compared with patients with an ARCV 〈 40 mm ( = 25). Compared with patients without CAC ( = 42), patients with CAC ( = 101) showed a significantly higher presence of ARC (83.3% vs. 50.5%; 〈 0.001) and a higher mean ARCV (95.4 ± 116.2 mm vs. 29.7 ± 33.0 mm ; = 0.003). Severe CAC ( = 24) correlated with an increased mean ARCV (122.3 ± 148.8 mm ) compared to patients with minimal to moderate CAC ( = 33, mean ARCV: 61.9 ± 64.8 mm ; 〈 0.05). The extent of ARC is directly associated with the presence and degree of CAC on calcium-scoring scans during coronary DSCT angiography.

Keywords: Aortic Root Calcification ; Coronary Artery Calcification ; Calcium Scoring ; Coronary Computed Tomography Angiography ; Dual-Source Computed Tomography ; Medicine

ISSN: 0720-048X

E-ISSN: 1872-7727

DOI: 10.1016/j.ejrad.2015.06.003

URL: View record in ScienceDirect (Access to full text may be restricted)