Publications by authors named "Thom T J Veeger"

6 Publications

  • Page 1 of 1

A split-label design for simultaneous measurements of perfusion in distant slices by pulsed arterial spin labeling.

Magn Reson Med 2021 Jun 9. Epub 2021 Jun 9.

C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.

Purpose: Multislice arterial spin labeling (ASL) MRI acquisitions are currently challenging in skeletal muscle because of long transit times, translating into low-perfusion SNR in distal slices when large spatial coverage is required. However, fiber type and oxidative capacity vary along the length of healthy muscles, calling for multislice acquisitions in clinical studies. We propose a new variant of flow alternating inversion recovery (FAIR) that generates sufficient ASL signal to monitor exercise-induced perfusion changes in muscle in two distant slices.

Methods: Label around and between two 7-cm distant slices was created by applying the presaturation/postsaturation and selective inversion modules selectively to each slice (split-label multislice FAIR). Images were acquired using simultaneous multislice EPI. We validated our approach in the brain to take advantage of the high resting-state perfusion, and applied it in the lower leg muscle during and after exercise, interleaved with a single-slice FAIR as a reference.

Results: We show that standard multislice FAIR leads to an underestimation of perfusion, while the proposed split-label multislice approach shows good agreement with separate single-slice FAIR acquisitions in brain, as well as in muscle following exercise.

Conclusion: Split-label FAIR allows measuring muscle perfusion in two distant slices simultaneously without losing sensitivity in the distal slice.
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June 2021

Preserved thenar muscles in non-ambulant Duchenne muscular dystrophy patients.

J Cachexia Sarcopenia Muscle 2021 Jun 8;12(3):694-703. Epub 2021 May 8.

Duchenne Center, Leiden, Netherlands.

Background: Clinical trials in Duchenne muscular dystrophy (DMD) focus primarily on ambulant patients. Results cannot be extrapolated to later disease stages due to a decline in targeted muscle tissue. In non-ambulant DMD patients, hand function is relatively preserved and crucial for daily-life activities. We used quantitative MRI (qMRI) to establish whether the thenar muscles could be valuable to monitor treatment effects in non-ambulant DMD patients.

Methods: Seventeen non-ambulant DMD patients (range 10.2-24.1 years) and 13 healthy controls (range 9.5-25.4 years) underwent qMRI of the right hand at 3 T at baseline. Thenar fat fraction (FF), total volume (TV), and contractile volume (CV) were determined using 4-point Dixon, and T2 was determined using multiecho spin-echo. Clinical assessments at baseline (n = 17) and 12 months (n = 13) included pinch strength (kg), performance of the upper limb (PUL) 2.0, DMD upper limb patient reported outcome measure (PROM), and playing a video game for 10 min using a game controller. Group differences and correlations were assessed with non-parametric tests.

Results: Total volume was lower in patients compared with healthy controls (6.9 cm , 5.3-9.0 cm vs. 13.0 cm , 7.6-15.8 cm , P = 0.010). CV was also lower in patients (6.3 cm , 4.6-8.3 cm vs. 11.9 cm , 6.9-14.6 cm , P = 0.010). FF was slightly elevated (9.7%, 7.3-11.4% vs. 7.7%, 6.6-8.4%, P = 0.043), while T2 was higher (31.5 ms, 30.0-32.6 ms vs. 28.1 ms, 27.8-29.4 ms, P < 0.001). Pinch strength and PUL decreased over 12 months (2.857 kg, 2.137-4.010 to 2.243 kg, 1.930-3.339 kg, and 29 points, 20-36 to 23 points, 17-30, both P < 0.001), while PROM did not (49 points, 36-57 to 44 points, 30-54, P = 0.041). All patients were able to play for 10 min at baseline or follow-up, but some did not comply with the study procedures regarding this endpoint. Pinch strength correlated with TV and CV in patients (rho = 0.72 and rho = 0.68) and controls (both rho = 0.89). PUL correlated with TV, CV, and T2 (rho = 0.57, rho = 0.51, and rho = -0.59).

Conclusions: Low thenar FF, increased T2 , correlation of muscle size with strength and function, and the decrease in strength and function over 1 year indicate that the thenar muscles are a valuable and quantifiable target for therapy in later stages of DMD. Further studies are needed to relate these data to the loss of a clinically meaningful milestone.
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June 2021

Fear of movement is not associated with trunk movement variability during gait in patients with low back pain.

Spine J 2020 12 22;20(12):1986-1994. Epub 2020 Jul 22.

MOVE Research Institute Amsterdam, VU University Amsterdam, Amsterdam, the Netherlands. Electronic address:

Background: Literature describing differences in motor control between low back pain (LBP) patients and healthy controls is very inconsistent, which may be an indication for the existence of subgroups. Pain-related psychological factors might play a role causing these differences.

Purpose: To examine the relation between fear of movement and variability of kinematics and muscle activation during gait in LBP patients.

Study Design: Cross-sectional experimental design.

Patient Sample: Thirty-one Chinese LBP patients.

Outcome Measures: Self-report measures: Visual Analog Score for pain; TAMPA-score; Physiologic measures: electromyography, range of motion.

Functional Measures: LBP history; the physical load of profession, physical activity.

Methods: Patients were divided in high and low fear of movement groups. Participants walked on a treadmill at four speeds: very slow, slow, preferred and fast. Kinematics of the thorax and the pelvis were recorded, together with the electromyography of five bilateral trunk muscle pairs. Kinematic and electromyography data were analysed in terms of stride-to-stride pattern variability. Factor analysis was applied to assess interdependence of 11 variability measures. To test for differences between groups, a mixed-design multivariate analysis of variance was conducted.

Results: Kinematic variability and variability of muscle activation consistently loaded on different factors and thus represented different underlying variables. No significant Group effects on variability of kinematics and muscle activation were found (Hotelling's Trace F=0.237; 0.396, p=.959; .846, respectively). Speed significantly decreased kinematic variability and increased variability in muscle activation (Hotelling's Trace F=8.363; 4.595, p<.0001; <.0001, respectively). No significant interactions between Group and Speed were found (Hotelling's Trace F=0.204; 0.100, p=.762; .963, respectively).

Conclusions: The results of this study do not support the hypothesis that variability in trunk kinematics and trunk muscle activation during gait in LBP patients are associated with fear of movement.
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December 2020

Water-fat separation in spiral magnetic resonance fingerprinting for high temporal resolution tissue relaxation time quantification in muscle.

Magn Reson Med 2020 08 3;84(2):646-662. Epub 2020 Jan 3.

C.J. Gorter Center for High Field MRI, Radiology, Leiden University Medical Center, Leiden, Netherlands.

Purpose: To minimize the known biases introduced by fat in rapid T and T quantification in muscle using a single-run magnetic resonance fingerprinting (MRF) water-fat separation sequence.

Methods: The single-run MRF acquisition uses an alternating in-phase/out-of-phase TE pattern to achieve water-fat separation based on a 2-point DIXON method. Conjugate phase reconstruction and fat deblurring were applied to correct for B inhomogeneities and chemical shift blurring. Water and fat signals were matched to the on-resonance MRF dictionary. The method was first tested in a multicompartment phantom. To test whether the approach is capable of measuring small in vivo dynamic changes in relaxation times, experiments were run in 9 healthy volunteers; parameter values were compared with and without water-fat separation during muscle recovery after plantar flexion exercise.

Results: Phantom results show the robustness of the water-fat resolving MRF approach to undersampling. Parameter maps in volunteers show a significant (P < .01) increase in T (105 ± 94 ms) and decrease in T (14 ± 6 ms) when using water-fat-separated MRF, suggesting improved parameter quantification by reducing the well-known biases introduced by fat. Exercise results showed smooth T and T recovery curves.

Conclusion: Water-fat separation using conjugate phase reconstruction is possible within a single-run MRF scan. This technique can be used to rapidly map relaxation times in studies requiring dynamic scanning, in which the presence of fat is problematic.
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August 2020

Improving Mobility Performance in Wheelchair Basketball.

J Sport Rehabil 2019 Jan;28(1):59-66

Objective: This study aimed to investigate which characteristics of athlete, wheelchair and athlete-wheelchair interface are the best predictors of wheelchair basketball mobility performance.

Design: A total of 60 experienced wheelchair basketball players performed a wheelchair mobility performance test to assess their mobility performance. To determine which variables were the best predictors of mobility performance, forward stepwise linear regression analyses were performed on a set of 33 characteristics, including 10 athlete, 19 wheelchair, and 4 athlete-wheelchair interface characteristics.

Results: A total of 8 of the characteristics turned out to be significant predictors of wheelchair basketball mobility performance. Classification, experience, maximal isometric force, wheel axis height, and hand rim diameter-which both are interchangeable with each other and wheel diameter-camber angle, and the vertical distance between shoulder and rear wheel axis-which was interchangeable with seat height-were positively associated with mobility performance. The vertical distance between the front seat and the footrest was negatively associated with mobility performance.

Conclusion: With this insight, coaches and biomechanical specialists are provided with statistical findings to determine which characteristics they could focus on best to improve mobility performance. Six out of 8 predictors are modifiable and can be optimized to improve mobility performance. These adjustments could be carried out both in training (maximal isometric force) and in wheelchair configurations (eg, camber angle).
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January 2019

Evidence of splinting in low back pain? A systematic review of perturbation studies.

Eur Spine J 2018 Jan 12;27(1):40-59. Epub 2017 Sep 12.

Amsterdam Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.

Purpose: The purpose of this systematic review was to assess whether LBP patients demonstrate signs of splinting by evaluating the reactions to unexpected mechanical perturbations in terms of (1) trunk muscle activity, (2) kinetic and (3) kinematic trunk responses and (4) estimated mechanical properties of the trunk.

Methods: The literature was systematically reviewed to identify studies that compared responses to mechanical trunk perturbations between LBP patients and healthy controls in terms of muscle activation, kinematics, kinetics, and/or mechanical properties. If more than four studies reported an outcome, the results of these studies were pooled.

Results: Nineteen studies were included, of which sixteen reported muscle activation, five kinematic responses, two kinetic responses, and two estimated mechanical trunk properties. We found evidence of a longer response time of muscle activation, which would be in line with splinting behaviour in LBP. No signs of splinting behaviour were found in any of the other outcome measures.

Conclusions: We conclude that there is currently no convincing evidence for the presence of splinting behaviour in LBP patients, because we found no indications for splinting in terms of kinetic and kinematic responses to perturbation and derived mechanical properties of the trunk. Consistent evidence on delayed onsets of muscle activation in response to perturbations was found, but this may have other causes than splinting behaviour.
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January 2018