Quantitative assessment of the effects of 6 months of adapted physical activity on gait in people with multiple sclerosis: a randomized controlled trial

Purpose: The purpose of this study is to quantitatively assess the effect of 6 months of supervised adapted physical activity (APA i.e. physical activity designed for people with special needs) on spatio-temporal and kinematic parameters of gait in persons with Multiple Sclerosis (pwMS).

Methods: Twenty-two pwMS with Expanded Disability Status Scale scores ranging from 1.5 to 5.5 were randomly assigned either to the intervention group (APA, n?=?11) or the control group (CG, n?=?11). The former underwent 6 months of APA consisting of 3 weekly 60-min sessions of aerobic and strength training, while CG participants were engaged in no structured PA program. Gait patterns were analyzed before and after the training using three-dimensional gait analysis by calculating spatio-temporal parameters and concise indexes of gait kinematics (Gait Profile Score – GPS and Gait Variable Score – GVS) as well as dynamic Range of Motion (ROM) of hip, knee, and ankle joints.

Results: The training originated significant improvements in stride length, gait speed and cadence in the APA group, while GPS and GVS scores remained practically unchanged. A trend of improvement was also observed as regard the dynamic ROM of hip, knee, and ankle joints. No significant changes were observed in the CG for any of the parameters considered.

Conclusions: The quantitative analysis of gait supplied mixed evidence about the actual impact of 6 months of APA on pwMS. Although some improvements have been observed, the substantial constancy of kinematic patterns of gait suggests that the full transferability of the administered training on the ambulation function may require more specific exercises.

• Implications for rehabilitation

• Adapted Physical Activity (APA) is effective in improving spatio-temporal parameters of gait, but not kinematics, in people with multiple sclerosis.

• Dynamic range of motion during gait is increased after APA.

• The full transferability of APA on the ambulation function may require specific exercises rather than generic lower limbs strength/flexibility training.

     

Whole abdominopelvic radiotherapy (WAPRT) using intensity-modulated arc therapy (IMAT): first clinical experience

PURPOSE: Whole abdominopelvic radiation therapy (WAPRT) is a treatment option in the palliation of patients with relapsed ovarian cancer. With conventional techniques, kidneys and liver are the dose- and homogeneity-limiting organs. We developed a planning strategy for intensity-modulated arc therapy (IMAT) and report on the treatment plans of the first 5 treated patients. METHODS AND MATERIALS: Five consecutive patients with histologically proven relapsed ovarian cancer were sent to our department for WAPRT. The target volumes and organs at risk (OAR) were delineated on 0.5-cm-thick CT slices. The clinical target volume (CTV) was defined as the total peritoneal cavity. CTV and kidneys were expanded with 0.5 cm. In a preset range of 8 degrees interspaced gantry angles, machine states were generated with an anatomy-based segmentation tool. Machine states of the same class were stratified in arcs. The optimization of IMAT was done in several steps, using a biophysical objective function. These steps included weight optimization of machine states, leaf position optimization adapted to meet the maximal leaf speed constraint, and planner-interactive optimization of the start and stop angles. The final control points (machine states plus associated cumulative monitor unit counts) were calculated using a collapsed cone convolution/superposition algorithm. For comparison, two conventional plans (CONV) were made, one with two fields (CONV2), and one with four fields (CONV4). In these CONV plans, dose to the kidneys was limited by cerrobend blocks. The IMAT and the CONV plans were normalized to a median dose of 33 Gy to the planning target volume (PTV). Monomer/polymer gel dosimetry was used to assess the dosimetric accuracy of the IMAT planning and delivery method. RESULTS: The median volume of the PTV was 8306 cc. The mean treatment delivery time over 4 patients was 13.8 min. A mean of 444 monitor units was needed for a fraction dose of 150 cGy. The fraction of the PTV volume receiving more than 90% of the prescribed dose (V(90)) was 9% higher for the IMAT plan than for the CONV4 plan (89.9% vs. 82.5%). Outside a build-up region of 0.8 cm and 1 cm away from both kidneys, the inhomogeneity in the PTV was 15.1% for the IMAT plans and 24.9% for the CONV4 plans (for CONV2 plans, this was 34.9%). The median dose to the kidneys in the IMAT plans was lower for all patients. The 95th percentile dose for the kidneys was significantly higher for the IMAT plans than for the CONV4 and CONV2 plans (28.2 Gy vs. 22.2 Gy and 22.6 Gy for left kidney, respectively). No relevant differences were found for liver. The gel-measured dose was within clinical planning constraints. CONCLUSION: IMAT was shown to be deliverable in an acceptable time slot and to produce dose distributions that are more homogeneous than those obtained with a CONV plan, with at least equal sparing of the OARs.     

Evaluation of the Sinmed Mastercouch as replacement for a standard couch.

BACKGROUND AND PURPOSE: Introducing into practice a new carbon-fibre couch necessitates its evaluation with regard to the present clinical situation. MATERIALS AND METHODS: In this study, a geometric and dosimetric evaluation has been made for the Sinmed Mastercouch as a replacement for the Elekta C-arm couch with Mylar-tennis racket combination. Geometrically, feasible gantry angles with regard to collision and beam intersection were discriminated as function of isocentric table rotation for 10 treatment isocentres. Dosimetrically, the build-up distortion and attenuation by the aforementioned tabletops and a carbon-fibre tabletop of an Elekta Precise simulator was measured. Finally, the clinical implications of these influences were assessed for a 3-field prostate treatment in three configurations: Mastercouch, C-arm couch and no-intersection situation. RESULTS: With regard to collision, the largest advantages are observed for the Mastercouch with the Omega-shaped treatment module compared to the C-arm couch for isocentres located in the upper part of the body, thanks to its shape and the absence of any metal. Dosimetrically, one has to take into account the build-up loss and attenuation by beam intersection with Mastercouch and the carbon-fibre edges of the tennis racket (C-arm couch). The clinical relevance of these dosimetric aspects depends on the dose delivered by the compromised beams.     

Decoupling initial electron beam parameters for Monte Carlo photon beam modelling by removing beam-modifying filters from the beam path

A new method is presented to decouple the parameters of the incident e(-) beam hitting the target of the linear accelerator, which consists essentially in optimizing the agreement between measurements and calculations when the difference filter, which is an additional filter inserted in the linac head to obtain uniform lateral dose-profile curves for the high energy photon beam, and flattening filter are removed from the beam path. This leads to lateral dose-profile curves, which depend only on the mean energy of the incident electron beam, since the effect of the radial intensity distribution of the incident e- beam is negligible when both filters are absent. The location of the primary collimator and the thickness and density of the target are not considered as adjustable parameters, since a satisfactory working Monte Carlo model is obtained for the low energy photon beam (6 MV) of the linac using the same target and primary collimator. This method was applied to conclude that the mean energy of the incident e- beam for the high energy photon beam (18 MV) of our Elekta SLi Plus linac is equal to 14.9 MeV. After optimizing the mean energy, the modelling of the filters, in accordance with the information provided by the manufacturer, can be verified by positioning only one filter in the linac head while the other is removed. It is also demonstrated that the parameter setting for Bremsstrahlung angular sampling in BEAMnrc ('Simple' using the leading term of the Koch and Motz equation or 'KM' using the full equation) leads to different dose-profile curves for the same incident electron energy for the studied 18 MV beam. It is therefore important to perform the calculations in 'KM' mode. Note that both filters are not physically removed from the linac head. All filters remain present in the linac head and are only rotated out of the beam. This makes the described method applicable for practical usage since no recommissioning process is required.     

Between colonial medicine and global health: protein malnutrition and UNICEF milk in the Belgian Congo

During the last decades of colonial rule, Belgian colonial authorities, health agencies and researchers intensely engaged with kwashiorkor, a severe syndrome that was deemed widespread among young children in some parts of the Belgian Congo and Ruanda-Urundi and chiefly attributed to protein malnutrition. To fight kwashiorkor, the Belgian government, in the early 1950s, set up a joint milk distribution campaign with the United Nations International Children’s Emergency Fund, Food and Agriculture Organization and World Health Organization, the first of its kind in colonial Africa. Placing this campaign in the context of mounting international and inter-imperial concern about kwashiorkor and other nutritional problems in Africa and across the globe, this article explores its rationales, mechanisms and consequences, and in particular, how the campaign was shaped and publicised by FORÉAMI, one of the main health providers on the ground. It not only contributes to the history of European colonial medicine and nutritional policies, but also opens new perspectives on international health collaboration during late colonialism. It argues that Belgian authorities were wary of international interference in colonial policies, but that especially FORÉAMI also viewed and used the campaign as an opportunity to display its ‘mastery’ in rural and infant healthcare and control the narrative on Belgium’s colonial medicine.     

A multicentRE observational analysiS of PErsistenCe to Treatment in the new multiple sclerosis era: the RESPECT study

Journal of Neurology - In this independent, multicenter, retrospective study, we investigated the short-term persistence to treatment with first-line self-injectable or oral disease-modifying...     

‘Timed up and go’ and brain atrophy: a preliminary MRI study to assess functional mobility performance in multiple sclerosis

Motor and cognitive disabilities are related to brain atrophy in multiple sclerosis (MS). ‘Timed up and go’ (TUG) has been recently tested in MS as functional mobility test, as it is able to evaluate ambulation/coordination-related tasks, as well as cognitive function related to mobility. The objective of this study is to evaluate the relationship between brain volumes and TUG performances. Inclusion criteria were a diagnosis of MS and the ability to walk at least 20 m. TUG was performed using a wearable inertial sensor. Times and velocities of TUG sub-phases were calculated by processing trunk acceleration data. Patients underwent to a brain MRI, and volumes of whole brain, white matter (WM), grey matter (GM), and cortical GM (C) were estimated with SIENAX. Sixty patients were enrolled. Mean age was 41.5 ± 11.6 years and mean EDSS 2.3 ± 1.2. Total TUG duration was correlated to lower WM (ρ = 0.358, p = 0.005) and GM (ρ = 0.309, p = 0.017) volumes. A stronger association with lower GM volume was observed for intermediate (ρ = 0.427, p = 0.001) and final turning (ρ = 0.390, p = 0.002). TUG is a useful tool in a clinical setting as it can not only evaluate patients’ disability in terms of impaired functional mobility, but also estimate pathological features, such as grey atrophy.     

Automatic Generation of a Plan Optimization Volume for Tangential Field Breast Cancer Radiation Therapy

Background and Purpose: Dose homogeneity is one of the objectives during computer planning of postoperative radiotherapy of the conserved breast. For three-dimensional (3-D) optimization of the dose distribution using serial CT scan images, suitable volumes have to be delineated. The purpose of this study was to develop a computer-generated delineation of a plan optimization volume (POV) and an irradiated volume (IV) and to automate their use in a fast dose homogeneity optimization engine. Patients and Methods: Simulation was performed according to our standard procedure which involves the positioning of a lead collar around the palpable breast to facilitate the definition of gantry angle, collimator angle and field aperture for tangential wedged photon beams. In a change to the standard procedure an anterolateral radiograph was taken with its axis orthogonal to the central plane of the two tangential half-beams. Images from a serial CT scan were acquired in treatment position, and the geometric data of the three simulated beams were used by a computer program to generate the POV and IV. For each patient, weights of wedged and unwedged beams were optimized by either human heuristics using only the central slice (2-D), the whole set of CT slices (3-D), or by a computer algorithm using the POV, IV and lung volume with constrained matrix inversion (CMI) as optimization method. The resulting dose distributions were compared. Results: The total planning procedure took, on average, 44 min of which < 7 min were needed for human interactions, compared to about 52 min for the standard planning at Ghent University Hospital, Belgium. The simulation time is increased by 2–3 min. The method provides 3-D information of the dose distribution. Dose homogeneity and minimum dose inside the POV and maximum dose inside the IV were not significantly different for the three optimization techniques. Conclusion: This automated planning method is capable of replacing the contouring of the clinical target volume as well as the trial-and-error procedure of assigning weights of wedged and unwedged beams by an experienced planner.