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231 result(s) for "Schmidt, Michaela"
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Body image disturbance and associated eating disorder and body dysmorphic disorder pathology in gay and heterosexual men: A systematic analyses of cognitive, affective, behavioral und perceptual aspects
This study contributes to the quantitatively large, yet narrow in scope research on body image in gay men by assessing whether gay and heterosexual men systematically differ on various dimensions of body image disturbance and associated pathology, i.e., eating disorder and body dysmorphic disorder symptoms. Moreover, we examined the influence of general everyday discrimination experiences and involvement with the gay community on body image. N = 216 men (n = 112 gay men, n = 104 heterosexual men) participated in an online survey measuring the discrepancy between self-rated current and ideal body fat/ muscularity; drive for leanness, muscularity, and thinness; body satisfaction; body-related avoidance and checking; appearance fixing; overall body image disturbance; eating disorder and body dysmorphic disorder pathology; general everyday discrimination experiences; and involvement with the gay community. Gay men showed a greater discrepancy between self-rated current and ideal body fat; higher drive for thinness, body-related avoidance, appearance fixing, overall body image disturbance, eating disorder and body dysmorphic disorder pathology; and lower body appreciation than heterosexual men (all p ≤ .05). Contrary to expectation, everyday discrimination experiences were more strongly associated with body image disturbance and eating disorder/ body dysmorphic disorder pathology in heterosexual men than in gay men (all p ≤ .05). Gay community involvement was not associated with any body image disturbance-, ED-, or BDD aspect in gay men (all p ≥ .20). The results suggest greater body image disturbance in gay men than in heterosexual men regarding cognitions, emotions, behaviors, and perception as well as higher eating disorder and body dysmorphic disorder pathology. The results also suggest the dilemma of a thin, yet muscular body ideal in gay men. Surprisingly, discrimination experiences and involvement with the gay community did not explain differences in body image disturbance. Gay men may have become resilient to discrimination over time, and body ideals might differ across gay sub-communities.
Compressed sensing real-time cine imaging for assessment of ventricular function, volumes and mass in clinical practice
ObjectivesThis study was conducted in order to evaluate the accuracy of a compressed sensing (CS) real-time single-breath-hold cine sequence for the assessment of left and right ventricular functional parameters in daily practice.MethodsCardiac magnetic resonance (CMR) cine images were acquired from 100 consecutive patients using both the reference segmented multi-breath-hold steady-state free precession (SSFP) acquisition and a prototype single-breath-hold real-time CS sequence, providing the same slice number, position, and thickness. For both sequences, the left (LV) and right ventricular (RV) ejection fractions (EF) and end-diastolic volumes (EDV) were assessed as well as LV mass (LVM). The visualization of wall-motion disorders (WMD) and signal void related to mitral or tricuspid regurgitation was also analyzed.ResultsThe CS sequence mean scan time was 23 ± 6 versus 510 ± 109 s for the multi-breath-hold SSFP sequence (p < 0.001). There was an excellent correlation between the two sequences regarding mean LVEF (r = 0.995), LVEDV (r = 0.997), LVM (r = 0.981), RVEF (r = 0.979), and RVEDV (r = 0.983). Moreover, inter- and intraobserver agreements were very strong with intraclass correlations of 0.96 and 0.99, respectively. On CS images, mitral or tricuspid regurgitation visualization was good (AUC = 0.85 and 0.81, respectively; ROC curve analysis) and wall-motion disorder visualization was excellent (AUC ≥ 0.97).ConclusionCS real-time single-breath-hold cine imaging reduces CMR scan duration by almost 20 times in daily practice while providing reliable measurements of both left and right ventricles. There was no clinically relevant information loss regarding valve regurgitation and wall-motion disorder depiction.Key Points• Compressed sensing single-breath-hold real-time cine imaging is a reliable sequence in daily practice.• Fast CS real-time imaging reduces CMR scan time and improves patient workflow.• There is no clinically relevant information loss with CS regarding heart valve regurgitation or wall-motion disorders.
Compressed sensing real-time cine cardiovascular magnetic resonance: accurate assessment of left ventricular function in a single-breath-hold
Cardiovascular cine magnetic resonance (CMR) accelerated by compressed sensing (CS) is used to assess left ventricular (LV) function. However, it is difficult for prospective CS cine CMR to capture the complete end-diastolic phase, which can lead to underestimation of the end-diastolic volume (EDV), stroke volume (SV), and ejection fraction (EF), compared to retrospective standard cine CMR. This prospective study aimed to evaluate the diagnostic quality and accuracy of single-breath-hold full cardiac cycle CS cine CMR, acquired over two heart beats, to quantify LV volume in comparison to multi-breath-hold standard cine CMR. Eighty-one participants underwent standard segmented breath-hold cine and CS real-time cine CMR examinations to obtain a stack of eight contiguous short-axis images with same high spatial (1.7 × 1.7 mm2) and temporal resolution (41 ms). Two radiologists independently performed qualitative analysis of image quality (score, 1 [i.e., “nondiagnostic”] to 5 [i.e., “excellent”]) and quantitative analysis of the LV volume measurements. The total examination time was 113 ± 7 s for standard cine CMR and 24 ± 4 s for CS cine CMR (p < 0.0001). The CS cine image quality was slightly lower than standard cine (4.8 ± 0.5 for standard vs. 4.4 ± 0.5 for CS; p < 0.0001). However, all image quality scores for CS cine were above 4 (i.e., good). No significant differences existed between standard and CS cine MR for all quantitative LV measurements. The mean differences with 95 % confidence interval (CI), based on Bland–Altman analysis, were 1.3 mL (95 % CI, −14.6 – 17.2) for LV end-diastolic volume, 0.2 mL (95 % CI, −9.8 to10.3) for LV end-systolic volume, 1.1 mL (95 % CI, −10.5 to 12.7) for LV stroke volume, 1.0 g (95 % CI, −11.2 to 13.3) for LV mass, and 0.4 % (95 % CI, −4.8 – 5.6) for LV ejection fraction. The interobserver and intraobserver variability for CS cine MR ranged from −4.8 – 1.6 % and from −7.3 – 9.3 %, respectively, with slopes of the regressions ranging 0.88–1.0 and 0.86–1.03, respectively. Single-breath-hold full cardiac cycle CS real-time cine CMR could evaluate LV volume with excellent accuracy. It may replace multi-breath-hold standard cine CMR.
Efficacy of an internet-based, therapist-guided cognitive behavioral therapy intervention for adolescents and young adults with body dysmorphic disorder: a randomized controlled trial
Background Body dysmorphic disorder (BDD) is particularly prevalent yet highly understudied and undertreated in adolescence. This study evaluates the efficacy of an internet-based, therapist-guided cognitive behavioral therapy (CBT) for adolescents and young adults with BDD compared to supportive online therapy as an active control condition. Methods In a single-blind, randomized controlled trial, N  = 45 adolescents (aged 15–21 years) of all genders from German-speaking countries were assigned to 12 sessions of internet-based CBT (iCBT) or 12 weeks of supportive online therapy. The primary outcome was change in expert-rated BDD symptom severity from pre- to post-intervention (Yale-Brown Obsessive-Compulsive Scale Modified for Body Dysmorphic Disorder, BDD-YBOCS). Secondary outcomes included the remission and responder rate, changes in delusionality of appearance beliefs (BABS), self-rated BDD symptom severity (FKS), BDD cognitions (FKDK), quality of life (KINDL-R), and depressive symptoms (PHQ-9) from pre to post and to a 4-week follow-up. Results iCBT was more efficient than supportive online therapy on the BDD-YBOCS ( p  =.002), with a large between-group effect size at post-intervention (Hedges’ g ( SE ) = 0.93 (0.42)), and on all secondary measures ( p  <.05), except for depressive symptoms ( p  =.068). All secondary outcome measures also showed significant improvements from pre to post iCBT, with moderate to large effect sizes, and gains were stable until the 4-week follow-up period. iCBT participants showed higher remission (61.5%) and responder rates (66.7%), compared to controls (0% and 26.7%), but only the difference in remission reached significance. Conclusion The results indicate the efficacy of internet-based CBT in comparison to an active control condition, thus contributing to the limited intervention research in adolescent BDD and adding a much-needed treatment option. Trial registration : The trial was pre-registered on 2020/06/08 at the German Clinical Trials Register, DRKS00022055.
Motion-corrected 3D whole-heart water-fat high-resolution late gadolinium enhancement cardiovascular magnetic resonance imaging
Background Conventional 2D inversion recovery (IR) and phase sensitive inversion recovery (PSIR) late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) have been widely incorporated into routine CMR for the assessment of myocardial viability. However, reliable suppression of fat signal, and increased isotropic spatial resolution and volumetric coverage within a clinically feasible scan time remain a challenge. In order to address these challenges, this work proposes a highly efficient respiratory motion-corrected 3D whole-heart water/fat LGE imaging framework. Methods An accelerated IR-prepared 3D dual-echo acquisition and motion-corrected reconstruction framework for whole-heart water/fat LGE imaging was developed. The acquisition sequence includes 2D image navigators (iNAV), which are used to track the respiratory motion of the heart and enable 100% scan efficiency. Non-rigid motion information estimated from the 2D iNAVs and from the data itself is integrated into a high-dimensional patch-based undersampled reconstruction technique (HD-PROST), to produce high-resolution water/fat 3D LGE images. A cohort of 20 patients with known or suspected cardiovascular disease was scanned with the proposed 3D water/fat LGE approach. 3D water LGE images were compared to conventional breath-held 2D LGE images (2-chamber, 4-chamber and stack of short-axis views) in terms of image quality (1: full diagnostic to 4: non-diagnostic) and presence of LGE findings. Results Image quality was considered diagnostic in 18/20 datasets for both 2D and 3D LGE magnitude images, with comparable image quality scores (2D: 2.05 ± 0.72, 3D: 1.88 ± 0.90, p -value = 0.62) and overall agreement in LGE findings. Acquisition time for isotropic high-resolution (1.3mm 3 ) water/fat LGE images was 8.0 ± 1.4 min (3-fold acceleration, 60–88 slices covering the whole heart), while 2D LGE images were acquired in 5.6 ± 2.2 min (12–18 slices, including pauses between breath-holds) albeit with a lower spatial resolution (1.40–1.75 mm in-plane × 8 mm slice thickness). Conclusion A novel framework for motion-corrected whole-heart 3D water/fat LGE imaging has been introduced. The method was validated in patients with known or suspected cardiovascular disease, showing good agreement with conventional breath-held 2D LGE imaging, but offering higher spatial resolution, improved volumetric coverage and good image quality from a free-breathing acquisition with 100% scan efficiency and predictable scan time.
Simultaneous multi slice (SMS) balanced steady state free precession first-pass myocardial perfusion cardiovascular magnetic resonance with iterative reconstruction at 1.5 T
Background Simultaneous-Multi-Slice (SMS) perfusion imaging has the potential to acquire multiple slices, increasing myocardial coverage without sacrificing in-plane spatial resolution. To maximise signal-to-noise ratio (SNR), SMS can be combined with a balanced steady state free precession (bSSFP) readout. Furthermore, application of gradient-controlled local Larmor adjustment (GC-LOLA) can ensure robustness against off-resonance artifacts and SNR loss can be mitigated by applying iterative reconstruction with spatial and temporal regularisation. The objective of this study was to compare cardiovascular magnetic resonance (CMR) myocardial perfusion imaging using SMS bSSFP imaging with GC-LOLA and iterative reconstruction to 3 slice bSSFP. Methods Two contrast-enhanced rest perfusion sequences were acquired in random order in 8 patients: 6-slice SMS bSSFP and 3 slice bSSFP. All images were reconstructed with TGRAPPA. SMS images were also reconstructed using a non-linear iterative reconstruction with L1 regularisation in wavelet space (SMS-iter) with 7 different combinations for spatial (λ σ ) and temporal (λ τ ) regularisation parameters. Qualitative ratings of overall image quality (0 = poor image quality, 1 = major artifact, 2 = minor artifact, 3 = excellent), perceived SNR (0 = poor SNR, 1 = major noise, 2 = minor noise, 3 = high SNR), frequency of sequence related artifacts and patient related artifacts were undertaken. Quantitative analysis of contrast ratio (CR) and percentage of dark rim artifact (DRA) was performed. Results Among all SMS-iter reconstructions, SMS-iter 6 (λ σ 0.001 λ τ 0.005) was identified as the optimal reconstruction with the highest overall image quality, least sequence related artifact and higher perceived SNR. SMS-iter 6 had superior overall image quality (2.50 ± 0.53 vs 1.50 ± 0.53, p  = 0.005) and perceived SNR (2.25 ± 0.46 vs 0.75 ± 0.46, p  = 0.010) compared to 3 slice bSSFP. There were no significant differences in sequence related artifact, CR (3.62 ± 0.39 vs 3.66 ± 0.65, p  = 0.88) or percentage of DRA (5.25 ± 6.56 vs 4.25 ± 4.30, p  = 0.64) with SMS-iter 6 compared to 3 slice bSSFP. Conclusions SMS bSSFP with GC-LOLA and iterative reconstruction improved image quality compared to a 3 slice bSSFP with doubled spatial coverage and preserved in-plane spatial resolution. Future evaluation in patients with coronary artery disease is warranted.
Feasibility of contrast-enhanced coronary artery magnetic resonance angiography using compressed sensing
Background Coronary magnetic resonance angiography (CMRA) is a promising technique for assessing the coronary arteries. However, a disadvantage of CMRA is the comparatively long acquisition time. Compressed sensing (CS) can considerably reduce the scan time. The aim of this study was to verify the feasibility of CS CMRA scanning during the waiting time between contrast injection and late gadolinium enhancement (LGE) scan in a clinical protocol. Methods Fifty clinical patients underwent contrast-enhanced CS CMRA and conventional CMRA on a 3 T CMR scanner. After contrast injection, CS CMRA was scanned during the waiting time for LGE CMR. A conventional CMRA scan was performed after LGE CMR. We assessed acquisition times and coronary artery image quality for each segment on a 4-point scale. Visible vessel length, sharpness and diameter of right (RCA), left anterior descending (LAD), and left circumflex (LCX) coronary arteries were also quantitatively compared among the scans. Results All CS CMRA scans were successfully performed within the LGE waiting time. The median total scan time was 207 s (163, 259 s) for CS and 785 s (698, 975 s) for conventional CMRA ( p  < 0.001). No significant differences were observed in image quality scores, vessel length measurements, sharpness, and diameter between CS and conventional CMRA. Conclusions We could achieve all CS CMRA scans within the LGE waiting time. Contrast-enhanced CS CMRA could considerably shorten the scan time while maintaining image quality compared with conventional CMRA.
Automated detection of cardiac rest period for trigger delay calculation for image-based navigator coronary magnetic resonance angiography
BackgroundCoronary magnetic resonance angiography (coronary MRA) is increasingly being considered as a clinically viable method to investigate coronary artery disease (CAD). Accurate determination of the trigger delay to place the acquisition window within the quiescent part of the cardiac cycle is critical for coronary MRA in order to reduce cardiac motion. This is currently reliant on operator-led decision making, which can negatively affect consistency of scan acquisition. Recently developed deep learning (DL) derived software may overcome these issues by automation of cardiac rest period detection.MethodsThirty individuals (female, n = 10) were investigated using a 0.9 mm isotropic image-navigator (iNAV)-based motion-corrected coronary MRA sequence. Each individual was scanned three times utilising different strategies for determination of the optimal trigger delay: (1) the DL software, (2) an experienced operator decision, and (3) a previously utilised formula for determining the trigger delay. Methodologies were compared using custom-made analysis software to assess visible coronary vessel length and coronary vessel sharpness for the entire vessel length and the first 4 cm of each vessel.ResultsThere was no difference in image quality between any of the methodologies for determination of the optimal trigger delay, as assessed by visible coronary vessel length, coronary vessel sharpness for each entire vessel and vessel sharpness for the first 4 cm of the left mainstem, left anterior descending or right coronary arteries. However, vessel length of the left circumflex was slightly greater using the formula method. The time taken to calculate the trigger delay was significantly lower for the DL-method as compared to the operator-led approach (106 ± 38.0 s vs 168 ± 39.2 s, p < 0.01, 95% CI of difference 25.5–98.1 s).ConclusionsDeep learning-derived automated software can effectively and efficiently determine the optimal trigger delay for acquisition of coronary MRA and thus may simplify workflow and improve reproducibility.
Compressed sensing acceleration of cardiac cine imaging allows reliable and reproducible assessment of volumetric and functional parameters of the left and right atrium
Objectives To compare volumetric and functional parameters of the atria derived from highly accelerated compressed sensing (CS)–based cine sequences in comparison to conventional (Conv) cine imaging. Methods CS and Conv cine sequences were acquired in 101 subjects (82 healthy volunteers (HV) and 19 patients with heart failure with reduced ejection fraction (HFrEF)) using a 3T MR scanner in this single-center study. Time-volume analysis of the left (LA) and right atria (RA) were performed in both sequences to evaluate atrial volumes and function (total, passive, and active emptying fraction). Inter-sequence and inter- and intra-reader agreement were analyzed using correlation, intraclass correlation (ICC), and Bland-Altman analysis. Results CS-based cine imaging led to a 69% reduction of acquisition time. There was significant difference in atrial parameters between CS and Conv cine, e.g., LA minimal volume (LAVmin) (Conv 24.0 ml (16.7–32.7), CS 25.7 ml (19.2–35.2), p  < 0.0001) or passive emptying fraction (PEF) (Conv 53.9% (46.7–58.4), CS 49.0% (42.0–54.1), p  < 0.0001). However, there was high correlation between the techniques, yielding good to excellent ICC (0.76–0.99) and small mean of differences in Bland-Altman analysis (e.g. LAVmin − 2.0 ml, PEF 3.3%). Measurements showed high inter- (ICC > 0.958) and intra-rater (ICC > 0.934) agreement for both techniques. CS-based parameters (PEF AUC = 0.965, LAVmin AUC = 0.864) showed equivalent diagnostic ability compared to Conv cine imaging (PEF AUC = 0.989, LAVmin AUC = 0.859) to differentiate between HV and HFrEF. Conclusion Atrial volumetric and functional evaluation using CS cine imaging is feasible with relevant reduction of acquisition time, therefore strengthening the role of CS in clinical CMR for atrial imaging. Key Points • Reliable assessment of atrial volumes and function based on compressed sensing cine imaging is feasible. • Compressed sensing reduces scan time and has the potential to overcome obstacles of conventional cine imaging. • No significant differences for subjective image quality, inter- and intra-rater agreement, and ability to differentiate healthy volunteers and heart failure patients were detected between conventional and compressed sensing cine imaging.
Comparison between conventional and compressed sensing cine cardiovascular magnetic resonance for feature tracking global circumferential strain assessment
Background Feature tracking (FT) has become an established tool for cardiovascular magnetic resonance (CMR)-based strain analysis. Recently, the compressed sensing (CS) technique has been applied to cine CMR, which has drastically reduced its acquisition time. However, the effects of CS imaging on FT strain analysis need to be carefully studied. This study aimed to investigate the use of CS cine CMR for FT strain analysis compared to conventional cine CMR. Methods Sixty-five patients with different left ventricular (LV) pathologies underwent both retrospective conventional cine CMR and prospective CS cine CMR using a prototype sequence with the comparable temporal and spatial resolution at 3 T. Eight short-axis cine images covering the entire LV were obtained and used for LV volume assessment and FT strain analysis. Prospective CS cine CMR data over 1.5 heartbeats were acquired to capture the complete end-diastolic data between the first and second heartbeats. LV volume assessment and FT strain analysis were performed using a dedicated software (ci 42 ; Circle Cardiovasacular Imaging, Calgary, Canada), and the global circumferential strain (GCS) and GCS rate were calculated from both cine CMR sequences. Results There were no significant differences in the GCS (− 17.1% [− 11.7, − 19.5] vs. − 16.1% [− 11.9, − 19.3; p = 0.508) and GCS rate (− 0.8 [− 0.6, − 1.0] vs. − 0.8 [− 0.7, − 1.0]; p = 0.587) obtained using conventional and CS cine CMR. The GCS obtained using both methods showed excellent agreement (y = 0.99x − 0.24; r = 0.95; p < 0.001). The Bland–Altman analysis revealed that the mean difference in the GCS between the conventional and CS cine CMR was 0.1% with limits of agreement between -2.8% and 3.0%. No significant differences were found in all LV volume assessment between both types of cine CMR. Conclusion CS cine CMR could be used for GCS assessment by CMR-FT as well as conventional cine CMR. This finding further enhances the clinical utility of high-speed CS cine CMR imaging.