GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Iodine overlays to improve differentiation between peritoneal carcinomatosis and benign peritoneal lesions
    Springer Science and Business Media LLC ; 2020
    In:  European Radiology Vol. 30, No. 7 ( 2020-07), p. 3968-3976
    Details
    In: European Radiology, Springer Science and Business Media LLC, Vol. 30, No. 7 ( 2020-07), p. 3968-3976
    Type of Medium: Online Resource
    ISSN: 0938-7994 , 1432-1084
    URL: Article
    DOI: 10.1007/s00330-020-06729-5
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2020
    detail.hit.zdb_id: 1472718-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Reduction of CT artifacts from cardiac implantable electronic devices using a combination of virtual monoenergetic images and post-processing algorithms
    Springer Science and Business Media LLC ; 2021
    In:  European Radiology Vol. 31, No. 9 ( 2021-09), p. 7151-7161
    Details
    In: European Radiology, Springer Science and Business Media LLC, Vol. 31, No. 9 ( 2021-09), p. 7151-7161
    Abstract: To evaluate the reduction of artifacts from cardiac implantable electronic devices (CIEDs) by virtual monoenergetic images (VMI), metal artifact reduction (MAR) algorithms, and their combination (VMI MAR ) derived from spectral detector CT (SDCT) of the chest compared to conventional CT images (CI). Methods In this retrospective study, we included 34 patients (mean age 74.6 ± 8.6 years), who underwent a SDCT of the chest and had a CIED in place. CI, MAR, VMI, and VMI MAR (10 keV increment, range: 100–200 keV) were reconstructed. Mean and standard deviation of attenuation (HU) among hypo- and hyperdense artifacts adjacent to CIED generator and leads were determined using ROIs. Two radiologists qualitatively evaluated artifact reduction and diagnostic assessment of adjacent tissue. Results Compared to CI, MAR and VMI MAR ≥ 100 keV significantly increased attenuation in hypodense and significantly decreased attenuation in hyperdense artifacts at CIED generator and leads ( p 〈 0.05). VMI ≥ 100 keV alone only significantly decreased hyperdense artifacts at the generator ( p 〈 0.05). Qualitatively, VMI ≥ 100 keV, MAR, and VMI MAR ≥ 100 keV provided significant reduction of hyper- and hypodense artifacts resulting from the generator and improved diagnostic assessment of surrounding structures ( p 〈 0.05). Diagnostic assessment of structures adjoining to the leads was only improved by MAR and VMI MAR 100 keV ( p 〈 0.05), whereas keV values ≥ 140 with and without MAR significantly worsened diagnostic assessment ( p 〈 0.05). Conclusions The combination of VMI and MAR as well as MAR as a standalone approach provides effective reduction of artifacts from CIEDs. Still, higher keV values should be applied with caution due to a loss of soft tissue and vessel contrast along the leads. Key Points • The combination of VMI and MAR as well as MAR as a standalone approach enables effective reduction of artifacts from CIEDs. • Higher keV values of both VMI and VMI MAR at CIED leads should be applied with caution since diagnostic assessment can be hampered by a loss of soft tissue and vessel contrast. • Recommended keV values for CIED generators are between 140 and 200 keV and for leads around 100 keV.
    Type of Medium: Online Resource
    ISSN: 0938-7994 , 1432-1084
    URL: Article
    DOI: 10.1007/s00330-021-07746-8
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2021
    detail.hit.zdb_id: 1472718-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Virtual monoenergetic images preserve diagnostic assessability in contrast media reduced abdominal spectral detector CT
    British Institute of Radiology ; 2020
    In:  The British Journal of Radiology Vol. 93, No. 1113 ( 2020-09-01), p. 20200340-
    Details
    In: The British Journal of Radiology, British Institute of Radiology, Vol. 93, No. 1113 ( 2020-09-01), p. 20200340-
    Abstract: To investigate if low-keV virtual monoenergetic images (VMI 40keV ) from abdominal spectral detector CT (SDCT) with reduced intravenous contrast media application (RCM) provide abdominal assessment similar to conventional images with standard contrast media (SCM) dose. Methods: 78 patients with abdominal SDCT were retrospectively included: 41 patients at risk for adverse reactions who received 44 RCM examinations with 50 ml and 37 patients who underwent 44 SCM examinations with 100 ml of contrast media (CM) and who were matched for effective body diameters. RCM, SCM images and RCM-VMI 40keV were reconstructed. Attenuation and signal-to-noise ratio (SNR) of liver, pancreas, kidneys, lymph nodes, psoas muscle, aorta and portal vein were assessed ROIs-based. Contrast-to-noise ratios (CNR) of lymph nodes vs aorta/portal vein were calculated. Two readers evaluated organ/vessel contrast, lymph node delineation, image noise and overall assessability using 4-point Likert scales. Results: RCM were inferior to SCM images in all quantitative/qualitative criteria. RCM-VMI 40keV and SCM images showed similar lymph node and muscle attenuation (p = 0.83,0.17), while for all other ROIs, RCM-VMI 40keV showed higher attenuation (p ≤ 0.05). SNR was comparable between RCM-VMI 40keV and SCM images (p range: 0.23–0.99). CNR of lymph nodes was highest in RCM-VMI 40keV (p ≤ 0.05). RCM-VMI 40keV received equivalent or higher scores than SCM in all criteria except for organ contrast, overall assessability and image noise, where SCM were superior (p ≤ 0.05). However, RCM-VMI 40keV received proper or excellent scores in 88.6/94.2/95.4% of the referring cases. Conclusions: VMI 40keV counteract contrast deterioration in CM reduced abdominal SDCT, facilitating diagnostic assessment. Advances in knowledge: SDCT-derived VMI 40keV provide adequate depiction of vessels, organs and lymph nodes even at notable CM reduction.
    Type of Medium: Online Resource
    ISSN: 0007-1285 , 1748-880X
    URL: Article
    DOI: 10.1259/bjr.20200340
    RVK:
    XA 34700
    Language: English
    Publisher: British Institute of Radiology
    Publication Date: 2020
    detail.hit.zdb_id: 1468548-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    DataSheet_1.docx
    Frontiers Media SA ; 2023
    In:  Frontiers in Endocrinology Vol. 14 ( 2023-5-19)
    Details
    In: Frontiers in Endocrinology, Frontiers Media SA, Vol. 14 ( 2023-5-19)
    Abstract: The bone marrow’s iodine uptake in dual-energy CT (DECT) is elevated in malignant disease. We aimed to investigate the physiological range of bone marrow iodine uptake after intravenous contrast application, and examine its dependence on vBMD, iodine blood pool, patient age, and sex. Method Retrospective analysis of oncological patients without evidence of metastatic disease. DECT examinations were performed on a spectral detector CT scanner in portal venous contrast phase. The thoracic and lumbar spine were segmented by a pre-trained neural network, obtaining volumetric iodine concentration data [mg/ml]. vBMD was assessed using a phantomless, CE-certified software [mg/cm3] . The iodine blood pool was estimated by ROI-based measurements in the great abdominal vessels. A multivariate regression model was fit with the dependent variable “median bone marrow iodine uptake”. Standardized regression coefficients (β) were calculated to assess the impact of each covariate. Results 678 consecutive DECT exams of 189 individuals (93 female, age 61.4 ± 16.0 years) were evaluated. AI-based segmentation provided volumetric data of 97.9% of the included vertebrae (n=11,286). The 95 th percentile of bone marrow iodine uptake, as a surrogate for the upper margin of the physiological distribution, ranged between 4.7-6.4 mg/ml. vBMD (p & lt;0.001, mean β=0.50) and portal vein iodine blood pool (p & lt;0.001, mean β=0.43) mediated the strongest impact. Based thereon, adjusted reference values were calculated. Conclusion The bone marrow iodine uptake demonstrates a distinct profile depending on vBMD, iodine blood pool, patient age, and sex. This study is the first to provide the adjusted reference values.
    Type of Medium: Online Resource
    ISSN: 1664-2392
    URL: Article
    URL: Article
    DOI: 10.3389/fendo.2023.1098898
    DOI: 10.3389/fendo.2023.1098898.s001
    Language: Unknown
    Publisher: Frontiers Media SA
    Publication Date: 2023
    detail.hit.zdb_id: 2592084-4
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Dual-Energy CT, Virtual Non-Calcium Bone Marrow Imaging of the Spine: An AI-Assisted, Volumetric Evaluation of a Reference Cohort with 500 CT Scans
    MDPI AG ; 2022
    In:  Diagnostics Vol. 12, No. 3 ( 2022-03-09), p. 671-
    Details
    In: Diagnostics, MDPI AG, Vol. 12, No. 3 ( 2022-03-09), p. 671-
    Abstract: Virtual non-calcium (VNCa) images from dual-energy computed tomography (DECT) have shown high potential to diagnose bone marrow disease of the spine, which is frequently disguised by dense trabecular bone on conventional CT. In this study, we aimed to define reference values for VNCa bone marrow images of the spine in a large-scale cohort of healthy individuals. DECT was performed after resection of a malignant skin tumor without evidence of metastatic disease. Image analysis was fully automated and did not require specific user interaction. The thoracolumbar spine was segmented by a pretrained convolutional neuronal network. Volumetric VNCa data of the spine’s bone marrow space were processed using the maximum, medium, and low calcium suppression indices. Histograms of VNCa attenuation were created for each exam and suppression setting. We included 500 exams of 168 individuals (88 female, patient age 61.0 ± 15.9). A total of 8298 vertebrae were segmented. The attenuation histograms’ overlap of two consecutive exams, as a measure for intraindividual consistency, yielded a median of 0.93 (IQR: 0.88–0.96). As our main result, we provide the age- and sex-specific bone marrow attenuation profiles of a large-scale cohort of individuals with healthy trabecular bone structure as a reference for future studies. We conclude that artificial-intelligence-supported, fully automated volumetric assessment is an intraindividually robust method to image the spine’s bone marrow using VNCa data from DECT.
    Type of Medium: Online Resource
    ISSN: 2075-4418
    URL: Article
    DOI: 10.3390/diagnostics12030671
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2662336-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Lymph Node Assessment in Prostate Cancer : Evaluation of Iodine Quantification With Spectral Detector CT in Correlation to PSMA PET/CT
    Ovid Technologies (Wolters Kluwer Health) ; 2021
    In:  Clinical Nuclear Medicine Vol. 46, No. 4 ( 2021-4), p. 303-309
    Details
    In: Clinical Nuclear Medicine, Ovid Technologies (Wolters Kluwer Health), Vol. 46, No. 4 ( 2021-4), p. 303-309
    Abstract: The aims of this study were to evaluate spectral detector CT (SDCT)–derived iodine concentration (IC) of lymph nodes diagnosed as metastatic and benign in prostate-specific membrane antigen (PSMA) PET/CT and to assess its potential use for lymph node assessment in prostate cancer. Patients and Methods Thirty-four prostate cancer patients were retrospectively included: 16 patients with and 18 without lymph node metastases as determined by PSMA PET/CT. Patients underwent PSMA PET/CT as well as portal venous phase abdominal SDCT for clinical cancer follow-up. Only scan pairs with a stable nodal status indicated by constant size as well as comparable prostate-specific antigen (PSA) levels were included. One hundred benign and 96 suspected metastatic lymph nodes were annotated and correlated between SDCT and PSMA PET/CT. Iodine concentration in SDCT-derived iodine maps and SUV max in ultra-high definition reconstructions from PSMA PET/CT were acquired based on the region of interest. Results Metastatic lymph nodes as per PSMA PET/CT showed higher IC than nonmetastatic nodes (1.9 ± 0.6 mg/mL vs 1.5 ± 0.5 mg/mL, P 〈 0.05) resulting in an AUC of 0.72 and sensitivity/specificity of 81.3%/58.5%. The mean short axis diameter of metastatic lymph nodes was larger than that of nonmetastatic nodes (6.9 ± 3.6 mm vs 5.3 ± 1.3 mm; P 〈 0.05); a size threshold of 1 cm short axis diameter resulted in a sensitivity/specificity of 12.8%/99.0%. There was a significant yet weak positive correlation between SUV max and IC ( r s = 0.25; P 〈 0.001). Conclusions Spectral detector CT–derived IC was increased in lymph nodes diagnosed as metastatic in PSMA PET/CT yet showed considerable data overlap. The correlation between IC and SUV max was weak, highlighting the role of PSMA PET/CT as important reference imaging modality for detection of lymph node metastases in prostate cancer patients.
    Type of Medium: Online Resource
    ISSN: 1536-0229 , 0363-9762
    URL: Article
    DOI: 10.1097/RLU.0000000000003496
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2021
    detail.hit.zdb_id: 2045053-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Use and Control of Artificial Intelligence in Patients Across the Medical Workflow: Single-Center Questionnaire Study of Patient Perspectives
    JMIR Publications Inc. ; 2021
    In:  Journal of Medical Internet Research Vol. 23, No. 2 ( 2021-2-17), p. e24221-
    Details
    In: Journal of Medical Internet Research, JMIR Publications Inc., Vol. 23, No. 2 ( 2021-2-17), p. e24221-
    Abstract: Artificial intelligence (AI) is gaining increasing importance in many medical specialties, yet data on patients’ opinions on the use of AI in medicine are scarce. Objective This study aimed to investigate patients’ opinions on the use of AI in different aspects of the medical workflow and the level of control and supervision under which they would deem the application of AI in medicine acceptable. Methods Patients scheduled for computed tomography or magnetic resonance imaging voluntarily participated in an anonymized questionnaire between February 10, 2020, and May 24, 2020. Patient information, confidence in physicians vs AI in different clinical tasks, opinions on the control of AI, preference in cases of disagreement between AI and physicians, and acceptance of the use of AI for diagnosing and treating diseases of different severity were recorded. Results In total, 229 patients participated. Patients favored physicians over AI for all clinical tasks except for treatment planning based on current scientific evidence. In case of disagreement between physicians and AI regarding diagnosis and treatment planning, most patients preferred the physician’s opinion to AI (96.2% [153/159] vs 3.8% [6/159] and 94.8% [146/154] vs 5.2% [8/154] , respectively; P=.001). AI supervised by a physician was considered more acceptable than AI without physician supervision at diagnosis (confidence rating 3.90 [SD 1.20] vs 1.64 [SD 1.03] , respectively; P=.001) and therapy (3.77 [SD 1.18] vs 1.57 [SD 0.96] , respectively; P=.001). Conclusions Patients favored physicians over AI in most clinical tasks and strongly preferred an application of AI with physician supervision. However, patients acknowledged that AI could help physicians integrate the most recent scientific evidence into medical care. Application of AI in medicine should be disclosed and controlled to protect patient interests and meet ethical standards.
    Type of Medium: Online Resource
    ISSN: 1438-8871
    URL: Article
    DOI: 10.2196/24221
    Language: English
    Publisher: JMIR Publications Inc.
    Publication Date: 2021
    detail.hit.zdb_id: 2028830-X
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Value of spectral detector computed tomography for the early assessment of technique efficacy after microwave ablation of hepatocellular carcinoma
    Public Library of Science (PLoS) ; 2021
    In:  PLOS ONE Vol. 16, No. 6 ( 2021-6-15), p. e0252678-
    Details
    In: PLOS ONE, Public Library of Science (PLoS), Vol. 16, No. 6 ( 2021-6-15), p. e0252678-
    Abstract: To investigate whether virtual monoenergetic images (VMI) and iodine maps derived from spectral detector computed tomography (SDCT) improve early assessment of technique efficacy in patients who underwent microwave ablation (MWA) for hepatocellular carcinoma (HCC) in liver cirrhosis. Methods This retrospective study comprised 39 patients with 49 HCC lesions treated with MWA. Biphasic SDCT was performed 7.7±4.0 days after ablation. Conventional images (CI), VMI and IM were reconstructed. Signal- and contrast-to-noise ratio (SNR, CNR) in the ablation zone (AZ), hyperemic rim (HR) and liver parenchyma were calculated using regions-of-interest analysis and compared between CI and VMI between 40–100 keV. Iodine concentration and perfusion ratio of HR and residual tumor (RT) were measured. Two readers evaluated subjective contrast of AZ and HR, technique efficacy (complete vs. incomplete ablation) and diagnostic confidence at determining technique efficacy. Results Attenuation of liver parenchyma, HR and RT, SNR of liver parenchyma and HR, CNR of AZ and HR were significantly higher in low-keV VMI compared to CI (all p 〈 0.05). Iodine concentration and perfusion ratio differed significantly between HR and RT (all p 〈 0.05; e.g. iodine concentration, 1.6±0.5 vs. 2.7±1.3 mg/ml). VMI 50keV improved subjective AZ-to-liver contrast, HR-to-liver contrast, visualization of AZ margin and vessels adjacent to AZ compared to CI (all p 〈 0.05). Diagnostic accuracy for detection of incomplete ablation was slightly higher in VMI 50keV compared to CI (0.92 vs. 0.89), while diagnostic confidence was significantly higher in VMI 50keV (p 〈 0.05). Conclusions Spectral detector computed tomography derived low-keV virtual monoenergetic images and iodine maps provide superior early assessment of technique efficacy of MWA in HCC compared to CI.
    Type of Medium: Online Resource
    ISSN: 1932-6203
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    DOI: 10.1371/journal.pone.0252678
    DOI: 10.1371/journal.pone.0252678.g001
    DOI: 10.1371/journal.pone.0252678.g002
    DOI: 10.1371/journal.pone.0252678.g003
    DOI: 10.1371/journal.pone.0252678.g004
    DOI: 10.1371/journal.pone.0252678.t001
    DOI: 10.1371/journal.pone.0252678.t002
    DOI: 10.1371/journal.pone.0252678.t003
    DOI: 10.1371/journal.pone.0252678.t004
    DOI: 10.1371/journal.pone.0252678.t005
    DOI: 10.1371/journal.pone.0252678.s001
    Language: English
    Publisher: Public Library of Science (PLoS)
    Publication Date: 2021
    detail.hit.zdb_id: 2267670-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Value of spectral detector computed tomography to differentiate infected from noninfected thoracoabominal fluid collections
    Elsevier BV ; 2021
    In:  European Journal of Radiology Vol. 145 ( 2021-12), p. 110037-
    Details
    In: European Journal of Radiology, Elsevier BV, Vol. 145 ( 2021-12), p. 110037-
    Type of Medium: Online Resource
    ISSN: 0720-048X
    URL: Article
    DOI: 10.1016/j.ejrad.2021.110037
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2021
    detail.hit.zdb_id: 2005350-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    Quantitative distribution of iodinated contrast media in body computed tomography: data from a large reference cohort
    Springer Science and Business Media LLC ; 2021
    In:  European Radiology Vol. 31, No. 4 ( 2021-04), p. 2340-2348
    Details
    In: European Radiology, Springer Science and Business Media LLC, Vol. 31, No. 4 ( 2021-04), p. 2340-2348
    Abstract: Dual-energy computed tomography allows for an accurate and reliable quantification of iodine. However, data on physiological distribution of iodine concentration (IC) is still sparse. This study aims to establish guidance for IC in abdominal organs and important anatomical landmarks using a large cohort of individuals without radiological tumor burden. Methods Five hundred seventy-one oncologic, portal venous phase dual-layer spectral detector CT studies of the chest and abdomen without tumor burden at time point of imaging confirmed by 〉 3-month follow-up were included. ROI were placed in parenchymatous organs ( n = 25), lymph nodes ( n = 6), and vessels ( n = 3) with a minimum of two measurements per landmark. ROI were placed on conventional images and pasted to iodine maps to retrieve absolute IC. Normalization to the abdominal aorta was conducted to obtain iodine perfusion ratios. Bivariate regression analysis, t tests, and ANOVA with Tukey-Kramer post hoc test were used for statistical analysis. Results Absolute IC showed a broad scatter and varied with body mass index, between different age groups and between the sexes in parenchymatous organs, lymph nodes, and vessels (range 0.0 ± 0.0 mg/ml–6.6 ± 1.3 mg/ml). Unlike absolute IC, iodine perfusion ratios did not show dependency on body mass index; however, significant differences between the sexes and age groups persisted, showing a tendency towards decreased perfusion ratios in elderly patients (e.g., liver 18–44 years/≥ 64 years: 0.50 ± 0.11/0.43 ± 0.10, p ≤ 0.05). Conclusions Distribution of IC obtained from a large-scale cohort is provided. As significant differences between sexes and age groups were found, this should be taken into account when obtaining quantitative iodine concentrations and applying iodine thresholds. Key Points • Absolute iodine concentration showed a broad variation and differed between body mass index, age groups, and between the sexes in parenchymatous organs, lymph nodes, and vessels. • The iodine perfusion ratios did not show dependency on body mass index while significant differences between sexes and age groups persisted. • Provided guidance values may serve as reference when aiming to differentiate healthy and abnormal tissue based on iodine perfusion ratios.
    Type of Medium: Online Resource
    ISSN: 0938-7994 , 1432-1084
    URL: Article
    DOI: 10.1007/s00330-020-07298-3
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2021
    detail.hit.zdb_id: 1472718-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...