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  1. Article: Conventional and Deep-Learning-Based Image Reconstructions of Undersampled K-Space Data of the Lumbar Spine Using Compressed Sensing in MRI: A Comparative Study on 20 Subjects.

    Fervers, Philipp / Zaeske, Charlotte / Rauen, Philip / Iuga, Andra-Iza / Kottlors, Jonathan / Persigehl, Thorsten / Sonnabend, Kristina / Weiss, Kilian / Bratke, Grischa

    Diagnostics (Basel, Switzerland)

    2023  Volume 13, Issue 3

    Abstract: ... of the k-space. Yet, excessive undersampling impairs image quality when using conventional reconstruction ... a combination of CS and a deep-learning-based reconstruction (CS AI) on raw k-space data acquired at different ... image reconstruction allows for stronger undersampling of k-space data without loss of image quality, and thus has ...

    Abstract Compressed sensing accelerates magnetic resonance imaging (MRI) acquisition by undersampling of the k-space. Yet, excessive undersampling impairs image quality when using conventional reconstruction techniques. Deep-learning-based reconstruction methods might allow for stronger undersampling and thus faster MRI scans without loss of crucial image quality. We compared imaging approaches using parallel imaging (SENSE), a combination of parallel imaging and compressed sensing (COMPRESSED SENSE, CS), and a combination of CS and a deep-learning-based reconstruction (CS AI) on raw k-space data acquired at different undersampling factors. 3D T2-weighted images of the lumbar spine were obtained from 20 volunteers, including a 3D sequence (standard SENSE), as provided by the manufacturer, as well as accelerated 3D sequences (undersampling factors 4.5, 8, and 11) reconstructed with CS and CS AI. Subjective rating was performed using a 5-point Likert scale to evaluate anatomical structures and overall image impression. Objective rating was performed using apparent signal-to-noise and contrast-to-noise ratio (aSNR and aCNR) as well as root mean square error (RMSE) and structural-similarity index (SSIM). The CS AI 4.5 sequence was subjectively rated better than the standard in several categories and deep-learning-based reconstructions were subjectively rated better than conventional reconstructions in several categories for acceleration factors 8 and 11. In the objective rating, only aSNR of the bone showed a significant tendency towards better results of the deep-learning-based reconstructions. We conclude that CS in combination with deep-learning-based image reconstruction allows for stronger undersampling of k-space data without loss of image quality, and thus has potential for further scan time reduction.
    Language English
    Publishing date 2023-01-23
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662336-5
    ISSN 2075-4418
    ISSN 2075-4418
    DOI 10.3390/diagnostics13030418
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Conventional and Deep-Learning-Based Image Reconstructions of Undersampled K-Space Data of the Lumbar Spine Using Compressed Sensing in MRI

    Philipp Fervers / Charlotte Zaeske / Philip Rauen / Andra-Iza Iuga / Jonathan Kottlors / Thorsten Persigehl / Kristina Sonnabend / Kilian Weiss / Grischa Bratke

    Diagnostics, Vol 13, Iss 418, p

    A Comparative Study on 20 Subjects

    2023  Volume 418

    Abstract: ... of the k-space. Yet, excessive undersampling impairs image quality when using conventional reconstruction ... a combination of CS and a deep-learning-based reconstruction (CS AI) on raw k-space data acquired at different ... image reconstruction allows for stronger undersampling of k-space data without loss of image quality, and thus has ...

    Abstract Compressed sensing accelerates magnetic resonance imaging (MRI) acquisition by undersampling of the k-space. Yet, excessive undersampling impairs image quality when using conventional reconstruction techniques. Deep-learning-based reconstruction methods might allow for stronger undersampling and thus faster MRI scans without loss of crucial image quality. We compared imaging approaches using parallel imaging (SENSE), a combination of parallel imaging and compressed sensing (COMPRESSED SENSE, CS), and a combination of CS and a deep-learning-based reconstruction (CS AI) on raw k-space data acquired at different undersampling factors. 3D T2-weighted images of the lumbar spine were obtained from 20 volunteers, including a 3D sequence (standard SENSE), as provided by the manufacturer, as well as accelerated 3D sequences (undersampling factors 4.5, 8, and 11) reconstructed with CS and CS AI. Subjective rating was performed using a 5-point Likert scale to evaluate anatomical structures and overall image impression. Objective rating was performed using apparent signal-to-noise and contrast-to-noise ratio (aSNR and aCNR) as well as root mean square error (RMSE) and structural-similarity index (SSIM). The CS AI 4.5 sequence was subjectively rated better than the standard in several categories and deep-learning-based reconstructions were subjectively rated better than conventional reconstructions in several categories for acceleration factors 8 and 11. In the objective rating, only aSNR of the bone showed a significant tendency towards better results of the deep-learning-based reconstructions. We conclude that CS in combination with deep-learning-based image reconstruction allows for stronger undersampling of k-space data without loss of image quality, and thus has potential for further scan time reduction.
    Keywords magnetic resonance imaging ; artificial intelligence ; image processing ; computer-assisted ; Medicine (General) ; R5-920
    Subject code 006
    Language English
    Publishing date 2023-01-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: The association between juvenile xanthogranulomas in neurofibromatosis type 1 patients and the development of leukaemia: A systematic review.

    Meyer, S N / Vaughn, A / Li, Y / Studer, A C / Rauen, K A / Kiuru, M

    Journal of the European Academy of Dermatology and Venereology : JEADV

    2023  Volume 37, Issue 12, Page(s) e1380–e1383

    MeSH term(s) Humans ; Neurofibromatosis 1/complications ; Xanthogranuloma, Juvenile/complications ; Leukemia
    Language English
    Publishing date 2023-07-20
    Publishing country England
    Document type Systematic Review ; Letter
    ZDB-ID 1128828-0
    ISSN 1468-3083 ; 0926-9959
    ISSN (online) 1468-3083
    ISSN 0926-9959
    DOI 10.1111/jdv.19321
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Ultrasound-controlled cryoneurolysis for peripheral mononeuropathies: a retrospective cohort study.

    Nemecek, Zdenek / Sturm, Constanze / Rauen, Anna C / Reisig, Florian / Streitberger, Konrad / Harnik, Michael A

    Pain management

    2023  Volume 13, Issue 6, Page(s) 363–372

    Abstract: Aim: ...

    Abstract Aim:
    MeSH term(s) Humans ; Mononeuropathies ; Neuralgia/therapy ; Pain Management/methods ; Retrospective Studies ; Treatment Outcome
    Language English
    Publishing date 2023-07-09
    Publishing country England
    Document type Evaluation Study ; Journal Article
    ZDB-ID 2617136-3
    ISSN 1758-1877 ; 1758-1869
    ISSN (online) 1758-1877
    ISSN 1758-1869
    DOI 10.2217/pmt-2023-0053
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Reconstruction of 3D knee MRI using deep learning and compressed sensing: a validation study on healthy volunteers.

    Dratsch, Thomas / Zäske, Charlotte / Siedek, Florian / Rauen, Philip / Hokamp, Nils Große / Sonnabend, Kristina / Maintz, David / Bratke, Grischa / Iuga, Andra

    European radiology experimental

    2024  Volume 8, Issue 1, Page(s) 47

    Abstract: Background: To investigate the potential of combining compressed sensing (CS) and artificial intelligence (AI), in particular deep learning (DL), for accelerating three-dimensional (3D) magnetic resonance imaging (MRI) sequences of the knee.: Methods!# ...

    Abstract Background: To investigate the potential of combining compressed sensing (CS) and artificial intelligence (AI), in particular deep learning (DL), for accelerating three-dimensional (3D) magnetic resonance imaging (MRI) sequences of the knee.
    Methods: Twenty healthy volunteers were examined using a 3-T scanner with a fat-saturated 3D proton density sequence with four different acceleration levels (10, 13, 15, and 17). All sequences were accelerated with CS and reconstructed using the conventional and a new DL-based algorithm (CS-AI). Subjective image quality was evaluated by two blinded readers using seven criteria on a 5-point-Likert-scale (overall impression, artifacts, delineation of the anterior cruciate ligament, posterior cruciate ligament, menisci, cartilage, and bone). Using mixed models, all CS-AI sequences were compared to the clinical standard (sense sequence with an acceleration factor of 2) and CS sequences with the same acceleration factor.
    Results: 3D sequences reconstructed with CS-AI achieved significantly better values for subjective image quality compared to sequences reconstructed with CS with the same acceleration factor (p ≤ 0.001). The images reconstructed with CS-AI showed that tenfold acceleration may be feasible without significant loss of quality when compared to the reference sequence (p ≥ 0.999).
    Conclusions: For 3-T 3D-MRI of the knee, a DL-based algorithm allowed for additional acceleration of acquisition times compared to the conventional approach. This study, however, is limited by its small sample size and inclusion of only healthy volunteers, indicating the need for further research with a more diverse and larger sample.
    Trial registration: DRKS00024156.
    Relevance statement: Using a DL-based algorithm, 54% faster image acquisition (178 s versus 384 s) for 3D-sequences may be possible for 3-T MRI of the knee.
    Key points: • Combination of compressed sensing and DL improved image quality and allows for significant acceleration of 3D knee MRI. • DL-based algorithm achieved better subjective image quality than conventional compressed sensing. • For 3D knee MRI at 3 T, 54% faster image acquisition may be possible.
    MeSH term(s) Humans ; Artificial Intelligence ; Deep Learning ; Healthy Volunteers ; Anterior Cruciate Ligament ; Magnetic Resonance Imaging
    Language English
    Publishing date 2024-04-15
    Publishing country England
    Document type Journal Article
    ISSN 2509-9280
    ISSN (online) 2509-9280
    DOI 10.1186/s41747-024-00446-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Conference proceedings: Schnellere 3D-MR-Bildgebung des Knies. Ein auf Deep Learning basierender Rekonstruktionsansatz für beschleunigte Bildgebung mit Compressed Sensing: Bewertung bei gesunden Probanden

    Dratsch, T / Zaeske, C / Siedek, F / Rauen, P / Große Hokamp, N / Sonnabend, K / Maintz, D / Bratke, G / Iuga, A

    RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren

    2024  Volume 196, Issue S 01

    Event/congress RÖKO 2024, RheinMain CongressCenter (RMCC) in Wiesbaden, 2024-05-08
    Language German
    Publishing date 2024-04-01
    Publisher Georg Thieme Verlag
    Publishing place Stuttgart ; New York
    Document type Article ; Conference proceedings
    ZDB-ID 554830-5
    ISSN 1438-9010 ; 1438-9029 ; 0340-1618 ; 0936-6652 ; 1433-5972
    ISSN (online) 1438-9010
    ISSN 1438-9029 ; 0340-1618 ; 0936-6652 ; 1433-5972
    DOI 10.1055/s-0044-1781590
    Database Thieme publisher's database

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  7. Article: Microvascular endothelial cells from human omentum lack an inward rectifier K+ current.

    Himmel, H M / Rauen, U / Ravens, U

    Physiological research

    2001  Volume 50, Issue 6, Page(s) 547–555

    Abstract: ... by the inwardly rectifying K+ current (I(K1)), whereas in microvascular EC the presence of I(K1) varies markedly ... rectifying current-voltage relation. Inward current was hardly sensitive to variations of extracellular [K+ ... the presence of a Ca2+-activated K+ current. In contrast to human omentum EC, EC from human iliac artery and ...

    Abstract In most macrovascular endothelial cell (EC) preparations, resting membrane potential is determined by the inwardly rectifying K+ current (I(K1)), whereas in microvascular EC the presence of I(K1) varies markedly. Cultured microvascular EC from small vessels of human omentum were examined by means of the voltage-clamp technique to elucidate the putative role of I(K1) in maintaining resting membrane potential. Macrovascular EC from human iliac artery and bovine aorta served as reference. Human omentum EC showed an outwardly rectifying current-voltage relation. Inward current was hardly sensitive to variations of extracellular [K+] and Ba2+ block suggesting lack of I(K1). However, substitution of extracellular [Na+] and/or [Cl-] affected the current-voltage relation indicating that Na+ and Cl- contribute to basal current. Furthermore, outward current was reduced by tetraethylammonium (10 mM), and cell-attached recordings suggested the presence of a Ca2+-activated K+ current. In contrast to human omentum EC, EC from human iliac artery and bovine aorta possessed inwardly rectifying currents which were sensitive to variations of extracellular [K+] and blocked by Ba2+. Thus, the lack of I(K1) in human omentum EC suggests that resting membrane potential is determined by Na+ and Cl- currents in addition to K+ outward currents.
    MeSH term(s) Animals ; Aorta/cytology ; Barium/pharmacology ; Cattle ; Cells, Cultured ; Chlorides/pharmacokinetics ; Endothelium, Vascular/cytology ; Endothelium, Vascular/physiology ; Humans ; Iliac Artery/cytology ; Membrane Potentials/physiology ; Microcirculation/physiology ; Omentum/blood supply ; Patch-Clamp Techniques ; Potassium/metabolism ; Potassium Channels, Inwardly Rectifying/physiology ; Sodium/pharmacokinetics
    Chemical Substances Chlorides ; Potassium Channels, Inwardly Rectifying ; Barium (24GP945V5T) ; Sodium (9NEZ333N27) ; Potassium (RWP5GA015D)
    Language English
    Publishing date 2001
    Publishing country Czech Republic
    Document type Journal Article
    ZDB-ID 1073141-6
    ISSN 1802-9973 ; 0862-8408 ; 0369-9463
    ISSN (online) 1802-9973
    ISSN 0862-8408 ; 0369-9463
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Bias in Sunscreen SPF Testing: A Review of Published Data.

    Ricci, Trina / Marra, Andrew / Rauen, Karen / Caswell, Michael

    Journal of cosmetic science

    2020  Volume 71, Issue 5, Page(s) 351–360

    Abstract: Subversion bias, a type of selection bias, through manipulation of subject recruitment compromises data validity. This study explores the possibility of subversion bias in sunscreen sun protection factor (SPF) testing. It has been established that ... ...

    Abstract Subversion bias, a type of selection bias, through manipulation of subject recruitment compromises data validity. This study explores the possibility of subversion bias in sunscreen sun protection factor (SPF) testing. It has been established that subjects with lower minimal erythemal dose (MED) values exhibit higher sunscreen SPF values. Consistency of this response is determined in subjects who participated in multiple sunscreen efficacy clinical trials. All trials determined the SPF of the sunscreen standard P2. Of the 652 subjects with greater than three observations (
    MeSH term(s) Sun Protection Factor ; Sunscreening Agents
    Chemical Substances Sunscreening Agents
    Language English
    Publishing date 2020-10-05
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1435667-3
    ISSN 1525-7886 ; 0037-9832
    ISSN 1525-7886 ; 0037-9832
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Traumatic Encephalopathy Syndrome and Tauopathy in a 19-Year-Old With Child Abuse.

    Rueb, Mike / Rauen, Katrin / Koerte, Inga Katharina / Gersing, Alexandra / Zetterberg, Henrik / Simrén, Joel / Brendel, Matthias / Adorjan, Kristina

    Neurotrauma reports

    2023  Volume 4, Issue 1, Page(s) 857–862

    Abstract: The majority of traumatic encephalopathy syndrome (TES) cases have been reported in former contact sport athletes. This is the first case with TES in a 19-year-old male patient with progressive cognitive decline after daily domestic physical violence ... ...

    Abstract The majority of traumatic encephalopathy syndrome (TES) cases have been reported in former contact sport athletes. This is the first case with TES in a 19-year-old male patient with progressive cognitive decline after daily domestic physical violence through repeated hits to the head for 15 years. The patient presented with a moderate depressive episode and progressive cognitive decline. Tau positron emission tomography (PET) with 220 MBq of [
    Language English
    Publishing date 2023-12-26
    Publishing country United States
    Document type Journal Article
    ISSN 2689-288X
    ISSN (online) 2689-288X
    DOI 10.1089/neur.2023.0078
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: White matter hyperintensity patterns: associations with comorbidities, amyloid, and cognition.

    Bachmann, Dario / von Rickenbach, Bettina / Buchmann, Andreas / Hüllner, Martin / Zuber, Isabelle / Studer, Sandro / Saake, Antje / Rauen, Katrin / Gruber, Esmeralda / Nitsch, Roger M / Hock, Christoph / Treyer, Valerie / Gietl, Anton

    Alzheimer's research & therapy

    2024  Volume 16, Issue 1, Page(s) 67

    Abstract: Background: White matter hyperintensities (WMHs) are often measured globally, but spatial patterns of WMHs could underlie different risk factors and neuropathological and clinical correlates. We investigated the spatial heterogeneity of WMHs and their ... ...

    Abstract Background: White matter hyperintensities (WMHs) are often measured globally, but spatial patterns of WMHs could underlie different risk factors and neuropathological and clinical correlates. We investigated the spatial heterogeneity of WMHs and their association with comorbidities, Alzheimer's disease (AD) risk factors, and cognition.
    Methods: In this cross-sectional study, we studied 171 cognitively unimpaired (CU; median age: 65 years, range: 50 to 89) and 51 mildly cognitively impaired (MCI; median age: 72, range: 53 to 89) individuals with available amyloid (18F-flutementamol) PET and FLAIR-weighted images. Comorbidities were assessed using the Cumulative Illness Rating Scale (CIRS). Each participant's white matter was segmented into 38 parcels, and WMH volume was calculated in each parcel. Correlated principal component analysis was applied to the parceled WMH data to determine patterns of WMH covariation. Adjusted and unadjusted linear regression models were used to investigate associations of component scores with comorbidities and AD-related factors. Using multiple linear regression, we tested whether WMH component scores predicted cognitive performance.
    Results: Principal component analysis identified four WMH components that broadly describe FLAIR signal hyperintensities in posterior, periventricular, and deep white matter regions, as well as basal ganglia and thalamic structures. In CU individuals, hypertension was associated with all patterns except the periventricular component. MCI individuals showed more diverse associations. The posterior and deep components were associated with renal disorders, the periventricular component was associated with increased amyloid, and the subcortical gray matter structures was associated with sleep disorders, endocrine/metabolic disorders, and increased amyloid. In the combined sample (CU + MCI), the main effects of WMH components were not associated with cognition but predicted poorer episodic memory performance in the presence of increased amyloid. No interaction between hypertension and the number of comorbidities on component scores was observed.
    Conclusion: Our study underscores the significance of understanding the regional distribution patterns of WMHs and the valuable insights that risk factors can offer regarding their underlying causes. Moreover, patterns of hyperintensities in periventricular regions and deep gray matter structures may have more pronounced cognitive implications, especially when amyloid pathology is also present.
    MeSH term(s) Humans ; Aged ; White Matter/pathology ; Cross-Sectional Studies ; Magnetic Resonance Imaging/methods ; Cognition ; Amyloidogenic Proteins ; Hypertension ; Alzheimer Disease/pathology ; Cognitive Dysfunction/diagnostic imaging ; Cognitive Dysfunction/epidemiology ; Cognitive Dysfunction/pathology
    Chemical Substances Amyloidogenic Proteins
    Language English
    Publishing date 2024-04-01
    Publishing country England
    Document type Journal Article
    ZDB-ID 2506521-X
    ISSN 1758-9193 ; 1758-9193
    ISSN (online) 1758-9193
    ISSN 1758-9193
    DOI 10.1186/s13195-024-01435-6
    Database MEDical Literature Analysis and Retrieval System OnLINE

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