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  1. Article ; Online: A Very Large Cardiac Channel Data Database (VLCD) Used to Evaluate Global Image Coherence (GIC) as an In Vivo Image Quality Metric.

    Rindal, Ole Marius Hoel / Bjastad, Tore Gruner / Espeland, Torvald / Berg, Erik Andreas Rye / Masoy, Svein-Erik

    IEEE transactions on ultrasonics, ferroelectrics, and frequency control

    2023  Volume 70, Issue 10, Page(s) 1295–1307

    Abstract: Ultrasound image quality is of utmost importance for a clinician to reach a correct diagnosis. Conventionally, image quality is evaluated using metrics to determine the contrast and resolution. These metrics require localization of specific regions and ... ...

    Abstract Ultrasound image quality is of utmost importance for a clinician to reach a correct diagnosis. Conventionally, image quality is evaluated using metrics to determine the contrast and resolution. These metrics require localization of specific regions and targets in the image such as a region of interest (ROI), a background region, and/or a point scatterer. Such objects can all be difficult to identify in in-vivo images, especially for automatic evaluation of image quality in large amounts of data. Using a matrix array probe, we have recorded a Very Large cardiac Channel data Database (VLCD) to evaluate coherence as an in vivo image quality metric. The VLCD consists of 33280 individual image frames from 538 recordings of 106 patients. We also introduce a global image coherence (GIC), an in vivo image quality metric that does not require any identified ROI since it is defined as an average coherence value calculated from all the data pixels used to form the image, below a preselected range. The GIC is shown to be a quantitative metric for in vivo image quality when applied to the VLCD. We demonstrate, on a subset of the dataset, that the GIC correlates well with the conventional metrics contrast ratio (CR) and the generalized contrast-to-noise ratio (gCNR) with R = 0.74 ( ) and R = 0.62 ( ), respectively. There exist multiple methods to estimate the coherence of the received signal across the ultrasound array. We further show that all coherence measures investigated in this study are highly correlated ( 0.9 and ) when applied to the VLCD. Thus, even though there are differences in the implementation of coherence measures, all quantify the similarity of the signal across the array and can be averaged into a GIC to evaluate image quality automatically and quantitatively.
    MeSH term(s) Humans ; Signal-To-Noise Ratio ; Ultrasonography/methods ; Phantoms, Imaging ; Image Processing, Computer-Assisted/methods
    Language English
    Publishing date 2023-10-17
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1525-8955
    ISSN (online) 1525-8955
    DOI 10.1109/TUFFC.2023.3308034
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Re: En kvinne i 70-årene med dekompensert hjertesvikt under operasjon.

    Espeland, Torvald / Moufack, Marcel

    Tidsskrift for den Norske laegeforening : tidsskrift for praktisk medicin, ny raekke

    2015  Volume 135, Issue 21, Page(s) 1921–1922

    Title translation Re: A woman in her 70s with decompensated heart failure during surgery.
    MeSH term(s) Female ; Heart Failure/drug therapy ; Humans ; Nitric Oxide/pharmacology ; Vasodilator Agents/pharmacology ; Ventricular Dysfunction, Right/drug therapy
    Chemical Substances Vasodilator Agents ; Nitric Oxide (31C4KY9ESH)
    Language Norwegian
    Publishing date 2015-11-17
    Publishing country Norway
    Document type Comment ; Letter
    ZDB-ID 603504-8
    ISSN 0807-7096 ; 0029-2001
    ISSN (online) 0807-7096
    ISSN 0029-2001
    DOI 10.4045/tidsskr.15.1129
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Moving ferromagnetic objects distorting cardiac magnetic resonance imaging.

    Espeland, Torvald / Berg, Erik Andreas Rye / Eriksen, Marius / Stensaeth, Knut Haakon

    European heart journal. Cardiovascular Imaging

    2019  Volume 21, Issue 2, Page(s) 153

    MeSH term(s) Foreign Bodies ; Heart ; Humans ; Magnetic Resonance Imaging
    Language English
    Publishing date 2019-08-01
    Publishing country England
    Document type Journal Article
    ZDB-ID 2638345-7
    ISSN 2047-2412 ; 2047-2404
    ISSN (online) 2047-2412
    ISSN 2047-2404
    DOI 10.1093/ehjci/jez214
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Implantation of cardioverter-defibrillators at St Olav’s Hospital 2006–15.

    Nyman, Mathias / Molaug, Ina Charlotte / Næss, Anne Marte / Espeland, Torvald / Loennechen, Jan Pål / Mjølstad, Ole Christian

    Tidsskrift for den Norske laegeforening : tidsskrift for praktisk medicin, ny raekke

    2020  Volume 140, Issue 13

    Abstract: Bakgrunn: Implantasjon av hjertestarter (implantable cardioverter defibrillator, ICD) er etablert behandling hos pasienter med høy risiko for plutselig hjertedød. Studiens formål var å kartlegge pasientkarakteristika, indikasjoner, hyppigheten av ICD- ... ...

    Title translation Implantasjon av hjertestartere ved St. Olavs hospital 2006–15.
    Abstract Bakgrunn: Implantasjon av hjertestarter (implantable cardioverter defibrillator, ICD) er etablert behandling hos pasienter med høy risiko for plutselig hjertedød. Studiens formål var å kartlegge pasientkarakteristika, indikasjoner, hyppigheten av ICD-støt, komplikasjoner, reoperasjoner samt endringer over tid i ICD-behandlingen ved St. Olavs hospital.
    Materiale og metode: Alle pasienter som fikk implantert hjertestarter ved St. Olavs hospital i perioden 2006-15 ble inkludert. Pasientene ble identifisert i pacemakerregisteret. Data ble hentet fra pacemakerregisteret og elektronisk pasientjournal.
    Resultater: Studien inkluderte 598 pasienter (82 % menn, medianalder 65 år). Tidligere hjertestans eller alvorlig arytmi forelå hos 401 (67 %) av dem som fikk implantert hjertestarter. Koronarsykdom (n = 383) var vanligste underliggende årsak. I oppfølgingstiden (median 3,6 år) fikk 203 (34 %) av pasientene ICD-støt, 154 (26 %) fikk berettigede og 65 (11 %) fikk uberettigede støt. Hos 139 (23 %) pasienter oppstod komplikasjoner. 101 (17 %) pasienter døde i oppfølgingsperioden.
    Fortolkning: Studien gir et godt grunnlag for kvalitetssikring av implantasjonsvirksomheten ved St. Olavs hospital. Kjønns- og aldersfordeling, indikasjon og underliggende årsaker for implantasjon samt hyppighet av støt og komplikasjoner samsvarer godt med tidligere publiserte data.
    Language Norwegian
    Publishing date 2020-09-28
    Publishing country Norway
    Document type English Abstract ; Journal Article
    ZDB-ID 603504-8
    ISSN 0807-7096 ; 0029-2001
    ISSN (online) 0807-7096
    ISSN 0029-2001
    DOI 10.4045/tidsskr.20.0115
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Aberration correction in 2D echocardiography.

    Måsøy, Svein-Erik / Dénarié, Bastien / Sørnes, Anders / Holte, Espen / Grenne, Bjørnar / Espeland, Torvald / Berg, Erik Andreas Rye / Rindal, Ole Marius Hoel / Rigby, Wayne / Bjåstad, Tore

    Quantitative imaging in medicine and surgery

    2023  Volume 13, Issue 7, Page(s) 4603–4617

    Abstract: Background: An aberration correction algorithm has been implemented and demonstrated in an echocardiographic clinical trial using two-dimensional (2D) imaging. The method estimates and compensates arrival time errors between different sub-aperture ... ...

    Abstract Background: An aberration correction algorithm has been implemented and demonstrated in an echocardiographic clinical trial using two-dimensional (2D) imaging. The method estimates and compensates arrival time errors between different sub-aperture processor (SAP) signals in a matrix array probe.
    Methods: Five standard views of channel data cineloops were recorded from 22 patients (11 male and 11 female) resulting in a total of 116 cineloops. The channel data were processed with and without the aberration correction algorithm, allowing for side-by-side comparison of images processed from the same channel data cineloops.
    Results: The aberration correction algorithm improved image quality, as quantified by a coherence metric, in all 7,380 processed frames. In a blinded and left-right-randomized side-by-side evaluation, four cardiologists (two experienced and two in training) preferred the aberration corrected cineloops in 97% of the cases. The clinicians reported that the corrected cineloops appeared sharper with better contrast and less noise. Many structures like valve leaflets, chordae, endocardium, and endocardial borders appeared narrower and more clearly defined in the aberration corrected images. An important finding is that aberration correction improves contrast between the endocardium and ventricle cavities for every processed image. The gain difference was confirmed by the cardiologists in their feedback and quantified with a median global gain difference estimate between the aberration-corrected and non-corrected images of 1.2 dB.
    Conclusions: The study shows the potential value of aberration correction in clinical echocardiography. Systematic improvement of images acquired with state-of-art equipment was observed both with quantitative metrics of image quality and clinician preference.
    Language English
    Publishing date 2023-05-30
    Publishing country China
    Document type Journal Article
    ZDB-ID 2653586-5
    ISSN 2223-4306 ; 2223-4292
    ISSN (online) 2223-4306
    ISSN 2223-4292
    DOI 10.21037/qims-22-895
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Automatic measurements of left ventricular volumes and ejection fraction by artificial intelligence: clinical validation in real time and large databases.

    Olaisen, Sindre / Smistad, Erik / Espeland, Torvald / Hu, Jieyu / Pasdeloup, David / Østvik, Andreas / Aakhus, Svend / Rösner, Assami / Malm, Siri / Stylidis, Michael / Holte, Espen / Grenne, Bjørnar / Løvstakken, Lasse / Dalen, Havard

    European heart journal. Cardiovascular Imaging

    2023  Volume 25, Issue 3, Page(s) 383–395

    Abstract: Aims: Echocardiography is a cornerstone in cardiac imaging, and left ventricular (LV) ejection fraction (EF) is a key parameter for patient management. Recent advances in artificial intelligence (AI) have enabled fully automatic measurements of LV ... ...

    Abstract Aims: Echocardiography is a cornerstone in cardiac imaging, and left ventricular (LV) ejection fraction (EF) is a key parameter for patient management. Recent advances in artificial intelligence (AI) have enabled fully automatic measurements of LV volumes and EF both during scanning and in stored recordings. The aim of this study was to evaluate the impact of implementing AI measurements on acquisition and processing time and test-retest reproducibility compared with standard clinical workflow, as well as to study the agreement with reference in large internal and external databases.
    Methods and results: Fully automatic measurements of LV volumes and EF by a novel AI software were compared with manual measurements in the following clinical scenarios: (i) in real time use during scanning of 50 consecutive patients, (ii) in 40 subjects with repeated echocardiographic examinations and manual measurements by 4 readers, and (iii) in large internal and external research databases of 1881 and 849 subjects, respectively. Real-time AI measurements significantly reduced the total acquisition and processing time by 77% (median 5.3 min, P < 0.001) compared with standard clinical workflow. Test-retest reproducibility of AI measurements was superior in inter-observer scenarios and non-inferior in intra-observer scenarios. AI measurements showed good agreement with reference measurements both in real time and in large research databases.
    Conclusion: The software reduced the time taken to perform and volumetrically analyse routine echocardiograms without a decrease in accuracy compared with experts.
    MeSH term(s) Humans ; Stroke Volume ; Artificial Intelligence ; Reproducibility of Results ; Ventricular Function, Left ; Echocardiography/methods ; Ventricular Dysfunction, Left/diagnostic imaging
    Language English
    Publishing date 2023-10-26
    Publishing country England
    Document type Journal Article
    ZDB-ID 2638345-7
    ISSN 2047-2412 ; 2047-2404
    ISSN (online) 2047-2412
    ISSN 2047-2404
    DOI 10.1093/ehjci/jead280
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Mechanical Wave Velocities in Left Ventricular Walls in Healthy Subjects and Patients With Aortic Stenosis.

    Espeland, Torvald / Wigen, Morten S / Dalen, Havard / Berg, Erik A R / Hammer, Tommy A / Salles, Sebastien / Lovstakken, Lasse / Amundsen, Brage H / Aakhus, Svend

    JACC. Cardiovascular imaging

    2023  Volume 17, Issue 2, Page(s) 111–124

    Abstract: Background: Mechanical wave velocity (MWV) measurement is a promising method for evaluating myocardial stiffness, because these velocities are higher in patients with myocardial disease.: Objectives: Using high frame rate echocardiography and a novel ...

    Abstract Background: Mechanical wave velocity (MWV) measurement is a promising method for evaluating myocardial stiffness, because these velocities are higher in patients with myocardial disease.
    Objectives: Using high frame rate echocardiography and a novel method for detection of myocardial mechanical waves, this study aimed to estimate the MWVs for different left ventricular walls and events in healthy subjects and patients with aortic stenosis (AS). Feasibility and reproducibility were evaluated.
    Methods: This study included 63 healthy subjects and 13 patients with severe AS. All participants underwent echocardiographic examination including 2-dimensional high frame rate recordings using a clinical scanner. Cardiac magnetic resonance was performed in 42 subjects. The authors estimated the MWVs at atrial kick and aortic valve closure in different left ventricular walls using the clutter filter wave imaging method.
    Results: Mechanical wave imaging in healthy subjects demonstrated the highest feasibility for the atrial kick wave reaching >93% for all 4 examined left ventricular walls. The MWVs were higher for the inferolateral and anterolateral walls (2.2 and 2.6 m/s) compared with inferoseptal and anteroseptal walls (1.3 and 1.6 m/s) (P < 0.05) among healthy subjects. The septal MWVs at aortic valve closure were significantly higher for patients with severe AS than for healthy subjects.
    Conclusions: MWV estimation during atrial kick is feasible and demonstrates higher velocities in the lateral walls, compared with septal walls. The authors propose indicators for quality assessment of the mechanical wave slope as an aid for achieving consistent measurements. The discrimination between healthy subjects and patients with AS was best for the aortic valve closure mechanical waves. (Ultrasonic Markers for Myocardial Fibrosis and Prognosis in Aortic Stenosis; NCT03422770).
    MeSH term(s) Humans ; Aortic Valve/diagnostic imaging ; Aortic Valve Stenosis ; Cardiomyopathies ; Healthy Volunteers ; Predictive Value of Tests ; Reproducibility of Results ; Ventricular Function, Left
    Language English
    Publishing date 2023-09-06
    Publishing country United States
    Document type Clinical Study ; Journal Article
    ZDB-ID 2491503-8
    ISSN 1876-7591 ; 1936-878X
    ISSN (online) 1876-7591
    ISSN 1936-878X
    DOI 10.1016/j.jcmg.2023.07.009
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Examining the educational impact of the mini-CEX: a randomised controlled study.

    Martinsen, Susanne Skjervold Smeby / Espeland, Torvald / Berg, Erik Andreas Rye / Samstad, Eivind / Lillebo, Børge / Slørdahl, Tobias S

    BMC medical education

    2021  Volume 21, Issue 1, Page(s) 228

    Abstract: Background: The purpose of this study is to evaluate the mini-Clinical Evaluation Exercise (mini-CEX) as a formative assessment tool among undergraduate medical students, in terms of student perceptions, effects on direct observation and feedback, and ... ...

    Abstract Background: The purpose of this study is to evaluate the mini-Clinical Evaluation Exercise (mini-CEX) as a formative assessment tool among undergraduate medical students, in terms of student perceptions, effects on direct observation and feedback, and educational impact.
    Methods: Cluster randomised study of 38 fifth-year medical students during a 16-week clinical placement. Hospitals were randomised to provide a minimum of 8 mini-CEXs per student (intervention arm) or continue with ad-hoc feedback (control arm). After finishing their clinical placement, students completed an Objective Structured Clinical Examination (OSCE), a written test and a survey.
    Results: All participants in the intervention group completed the pre-planned number of assessments, and 60% found them to be useful during their clinical placement. Overall, there were no statistically significant differences between groups in reported quantity or quality of direct observation and feedback. Observed mean scores were marginally higher on the OSCE and written test in the intervention group, but not statistically significant.
    Conclusions: There is considerable potential in assessing medical students during clinical placements and routine practice, but the educational impact of formative assessments remains mostly unknown. This study contributes with a robust study design, and may serve as a basis for future research.
    MeSH term(s) Clinical Clerkship ; Clinical Competence ; Educational Measurement ; Humans ; Physical Examination ; Students, Medical
    Language English
    Publishing date 2021-04-21
    Publishing country England
    Document type Journal Article ; Randomized Controlled Trial
    ZDB-ID 2044473-4
    ISSN 1472-6920 ; 1472-6920
    ISSN (online) 1472-6920
    ISSN 1472-6920
    DOI 10.1186/s12909-021-02670-3
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  9. Article ; Online: Combining Automatic Angle Correction and 3-D Tracking Doppler for the Assessment of Aortic Stenosis Severity.

    Fiorentini, Stefano / Espeland, Torvald / Berg, Erik Andreas Rye / Aakhus, Svend / Torp, Hans / Avdal, Jorgen

    IEEE transactions on ultrasonics, ferroelectrics, and frequency control

    2019  Volume 66, Issue 9, Page(s) 1404–1412

    Abstract: Aortic valve stenosis (AS) is a narrowing of the aortic valve opening, which causes increased load on the left ventricle. Untreated, this condition can eventually lead to heart failure and death. According to current recommendations, an accurate ... ...

    Abstract Aortic valve stenosis (AS) is a narrowing of the aortic valve opening, which causes increased load on the left ventricle. Untreated, this condition can eventually lead to heart failure and death. According to current recommendations, an accurate diagnosis of AS mandates the use of multiple acoustic windows to determine the highest velocity. Furthermore, the optimal positioning of both patient and transducer to reduce the beam-to-flow angle is emphasized. Being operator dependent, the beam alignment is a potential source of uncertainty. In this work, we perform noncompounded 3-D plane wave imaging for retrospective estimation of maximum velocities in aortic jets with automatic angle correction. This is achieved by combining a hybrid 3-D speckle tracking method to estimate the jet direction and 3-D tracking Doppler to generate angle-corrected sonograms, using the direction from speckle tracking as input. Results from simulations of flow through an orifice show that 3-D speckle tracking can estimate the jet orientation with acceptable accuracy for signal-to-noise ratios above 10 dB. Results from 12 subjects show that sonograms recorded from a standard apical view using the proposed method yield a maximum velocity that matches continuous wave (CW) Doppler sonograms recorded from the acoustic window with the lowest angle within a ±10% margin, provided that a high enough pulse repetition frequency could be achieved. These results motivate further validation and optimization studies.
    MeSH term(s) Algorithms ; Aortic Valve Stenosis/diagnostic imaging ; Blood Flow Velocity ; Computer Simulation ; Echocardiography, Doppler/methods ; Echocardiography, Three-Dimensional/methods ; Humans ; Patient Positioning ; Phantoms, Imaging ; Severity of Illness Index ; Transducers
    Language English
    Publishing date 2019-06-10
    Publishing country United States
    Document type Journal Article
    ISSN 1525-8955
    ISSN (online) 1525-8955
    DOI 10.1109/TUFFC.2019.2921818
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: 3D Myocardial Mechanical Wave Measurements: Toward In Vivo 3D Myocardial Elasticity Mapping.

    Salles, Sebastien / Espeland, Torvald / Molares, Alfonso / Aase, Svein Arne / Hammer, Tommy Arild / Støylen, Asbjørn / Aakhus, Svend / Lovstakken, Lasse / Torp, Hans

    JACC. Cardiovascular imaging

    2020  Volume 14, Issue 8, Page(s) 1495–1505

    Abstract: Objectives: This study aimed to investigate the potential of a novel 3-dimensional (3D) mechanical wave velocity mapping technique, based on the natural mechanical waves produced by the heart itself, to approach a noninvasive 3D stiffness mapping of the ...

    Abstract Objectives: This study aimed to investigate the potential of a novel 3-dimensional (3D) mechanical wave velocity mapping technique, based on the natural mechanical waves produced by the heart itself, to approach a noninvasive 3D stiffness mapping of the left ventricle.
    Background: Myocardial fibrosis is recognized as a pathophysiological substrate of major cardiovascular disorders such as cardiomyopathies and valvular heart disease. As fibrosis leads to increased myocardial stiffness, ultrasound elastography measurements could provide important clinical information.
    Methods: A 3D high frame rate imaging sequence was implemented on a high-end clinical ultrasound scanner to achieve 820 volumes/s when gating over 4 consecutive cardiac cycles. Five healthy volunteers and 10 patients with various degrees of aortic stenosis were included to evaluate feasibility and reproducibility. Mechanical waves were detected using the novel Clutter Filter Wave Imaging approach, shown to be highly sensitive to the weak tissue displacements caused by natural mechanical waves.
    Results: 3D spatiotemporal maps of mechanical wave velocities were produced for all subjects. Only the specific mechanical wave at atrial contraction provided a full 3D coverage of the left ventricle (LV). The average atrial kick propagation velocity was 1.6 ± 0.2 m/s in healthy volunteers and 2.8 ± 0.8 m/s in patients (p = 0.0016). A high correlation was found between mechanical wave velocity and age (R
    Conclusions: In this study, 3D LV mechanical wave velocities were visualized and measured in healthy volunteers and patients with aortic stenosis. The proposed imaging sequence and measurement technique allowed, for the first time, the measurement of full spatiotemporal 3D elasticity maps of the LV using ultrasound. (Ultrasonic markers for myocardial fibrosis and prognosis in aortic stenosis; NCT03422770).
    MeSH term(s) Aortic Valve/diagnostic imaging ; Contrast Media ; Elasticity ; Gadolinium ; Humans ; Predictive Value of Tests ; Reproducibility of Results
    Chemical Substances Contrast Media ; Gadolinium (AU0V1LM3JT)
    Language English
    Publishing date 2020-08-26
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2491503-8
    ISSN 1876-7591 ; 1936-878X
    ISSN (online) 1876-7591
    ISSN 1936-878X
    DOI 10.1016/j.jcmg.2020.05.037
    Database MEDical Literature Analysis and Retrieval System OnLINE

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