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We examined inflammatory cells, cytokines and growth factors in response to acute bouts of moderate intensity continuous exercise and high intensity intermittent exercise in youth with Crohn's disease and in healthy matched-controls. 15 patients and 15 controls performed 30 min of cycling at 50% of peak mechanical power (PMP) and 6 bouts of 4 × 15-s of cycling at 100 % PMP. Blood was collected at rest, at the mid-point, at the end of exercise and at 30 and 60 min into recovery. In patients with CD, both types of exercise increased immune cells and GH and decreased IGF-I. Moderate intensity exercise induced a greater increase in leukocytes (p < 0.05), neutrophils (p < 0.05), lymphocytes (p < 0.001), monocytes (p < 0.05), IL-6 (p < 0.05), IL-17 (p < 0.05) and GH (p < 0.05) and a similar decrease in IGF-I, compared with high intensity exercise. TNF-α did not change significantly with either exercise. Responses in patients were similar compared with controls; however, in patients monocytes remained elevated significantly longer in response to MICE. Youth with Crohn's disease can engage in distinctly different types of exercise without a significant acute exacerbation of inflammation. [ABSTRACT FROM AUTHOR]

Introduction: Regional hyperthermia systems with 3D power steering have been introduced to improve tumour temperatures. The 3D 70-MHz AMC-8 system has two rings of four waveguides. The aim of this study is to evaluate whether T90 will improve by using a higher operating frequency and whether further improvement is possible by adding a third ring. Methods: Optimised specific absorption rate (SAR) distributions were evaluated for a centrally located target in tissue-equivalent phantoms, and temperature optimisation was performed for five cervical carcinoma patients with constraints to normal tissue temperatures. The resulting T90 and the thermal iso-effect dose (i.e. the number of equivalent min at 43°°C) were evaluated and compared to the 2D 70-MHz AMC-4 system with a single ring of four waveguides. FDTD simulations were performed at 2.5 ×× 2.5 ×× 5 mm3 resolution. The applied frequencies were 70, 100, 120, 130, 140 and 150 MHz. Results: Optimised SAR distributions in phantoms showed an optimal SAR distribution at 140 MHz. For the patient simulations, an optimal increase in T90 was observed at 130 MHz. For a two-ring system at 70 MHz the gain in T90 was about 0.5°°C compared to the AMC-4 system, averaged over the five patients. At 130 MHz the average gain in T90 was ∼∼1.5°°C and ∼∼2°°C for a two and three-ring system, respectively. This implies an improvement of the thermal iso-effect dose with a factor ∼∼12 and ∼∼30, respectively. Conclusion: Simulations showed that a 130-MHz two-ring waveguide system yields significantly higher tumour temperatures compared to 70-MHz single-ring and double-ring waveguide systems. Temperatures were further improved with a 130-MHz triple-ring system. [ABSTRACT FROM AUTHOR]

Purpose: In this study hyperthermia treatment planning is used to investigate whether the target temperature during hyperthermia treatment can be increased using the 3D AMC-8 instead of the 2D AMC-4 system (AMC: Academic Medical Center). Methods and materials: The heating ability of the AMC-4 and AMC-8 system was analysed for five patients with cervix uteri carcinoma. Dielectric and thermal models were generated, based on a hyperthermia planning computerised tomography (CT), at a resolution of 2.5 ×× 2.5 ×× 5.0 mm3. Calculation of the electric fields with the finite-difference time-domain method was followed by SAR- and temperature-based optimisation. The ability to correct for axial shifts of the patient by phase/amplitude steering was investigated for both systems. Finally, it was investigated whether adjusting the ring-to-ring distance of the AMC-8 system can be used for further optimisation. Results: An average increase in T90 of ∼∼0.5°°C (0.2°°--0.8°°C) was found for the AMC-8 system compared to the AMC-4 system. The gain in T50 and T10 was also 0.5°°C on average. The additional power required to achieve this gain was 36%% to 71%% of the power required for the AMC-4 system. The AMC-8 system has the capability of correcting changes in axial position (−−8 cm, ++8 cm), contrary to the AMC-4 system. For both systems the axial position should be known within 1--2 cm. Conclusions: Hyperthermia treatment with the AMC-8 system can lead to a clinically relevant increase of the target temperature compared to treatment with the AMC-4 system. The AMC-8 system provides large freedom in the axial positioning of the patient. [ABSTRACT FROM AUTHOR]

Background: The aim of this study is preclinical evaluation of our newly developed regional hyperthermia system providing 3-D SAR control: the AMC-8 phased array consisting of two rings, each with four 70 MHz waveguides. It was designed to achieve higher tumour temperatures and improve the clinical effectiveness of locoregional hyperthermia. Methods: The performance of the AMC-8 system was evaluated with simulations and measurements aiming at heating a centrally located target region in rectangular (30 × 30 × 110 cm) and elliptical (36 × 24 × 80 cm) homogeneous tissue equivalent phantoms. Three properties were evaluated and compared to its predecessor, the 2-D AMC-4 single ring four waveguide array: (1) spatial control and (2) size of the SAR focus, (3) the ratio between maximum SAR outside the target region and SAR in the focus. Distance and phase difference between the two rings were varied. Results: (1) Phase steering provides 3-D SAR control for the AMC-8 system. (2) The SAR focus is more elongated compared to the AMC-4 system, yielding a lower SAR level in the focus when using the same total power. This is counter-balanced by (3) a superficial SAR deposition which is half of that in the AMC-4 system, yielding a more favourable ratio between normal tissue and target SAR and allowing higher total power and up to 30% more SAR in the focus for 3 cm ring distance. Conclusion: The AMC-8 system is capable of 3-D SAR control and its SAR distribution is more favourable than for the 2-D AMC-4 system. This result promises improvement in clinical tumour temperatures. [ABSTRACT FROM AUTHOR]

Cystinosis is a rare metabolic disorder characterized by lysosomal cystine accumulation leading to multi-organ damage, with kidneys being clinically first affected. Longer survival of cystinosis patients due to successful renal replacement therapy, revealed previously unknown extra-renal symptoms of cystinosis, generally appearing after the first decade. Respiratory insufficiency caused by overall respiratory muscle myopathy is a severely invalidating and sometimes a life-threatening complication of cystinosis. We report a successful treatment of hypoventilation, due to diaphragm myopathy in a cystinosis patient, by nocturnal non-invasive positive pressure ventilation (NIPPV). After initiation of NIPPV the clinical condition of the patient improved and blood-gasses normalized, indicating that this treatmentmodality should be considered in cystinosis patients with severe respiratory insufficiency. [ABSTRACT FROM AUTHOR]

Several studies have reported improved survival rates thanks to the use of an implantable cardioverter defibrillator (ICD) in the treatment of patients with life-threatening arrhythmia. However, the effects of the ICD on health-related quality of life (HR-QoL) of these patients are not clear. The aim of this study is to describe HR-QoL and fear of exercise in ICD patients. Eighty-nine ICD patients from the University Hospital in Groningen, the Netherlands, participated in this study. HR-QoL was measured using the Rand-36 and the Quality of Life After Myocardial Infarction Dutch language version questionnaires. Fear of exercise was measured using the Tampa Scale for Kinesiophobia, Dutch version and the Fear Avoidance Beliefs Questionnaire, Dutch version. Association between outcome variables was analysed by linear regression analyses. Study results show that the HR-QoL of patients with ICDs in our study population is significantly worse than that of normal healthy people. Furthermore, fear of exercise is negatively associated with HR-QoL corrected for sex, age and number of years living with an ICD. After implantation of the ICD, patients with a clear fear of exercise should be identified and interventions should be considered in order to increase their HR-QoL. [ABSTRACT FROM AUTHOR]

Background: In today's aging society, preventing or reducing disability is important. Physical activity may serve this goal. Generally, physical activity aims to enhance physical fitness, which in turn may prevent disability. The relationship between physical fitness and disability has been much less explored than the relationship between physical activity and physical fitness.Objective: To investigate the relationship between separate components of physical fitness and disability.Methods: The subjects were a community-based sample of 176 men and 233 women aged 65 years or older. Physical fitness was assessed with performance-based tests. Disability and potential confounders were assessed during face-to-face interviews.Results: Independently of other fitness components, walking endurance, grip strength, manual dexterity and balance contributed significantly to the prediction of disability for both men and women. Flexibility of the hip and spine, flexibility of the shoulder and reaction time were not independent predictors of disability for men or women. Physical fitness explained a greater percentage of variance in disability for women (31-48%) than for men (14-34%). Although depressive symptoms, cognitive functioning (men), number of chronic conditions (women) and age (women) explained additional variance in disability, these variables did not confound the relationship between physical fitness and disability.Conclusion: Walking endurance, grip strength and manual dexterity are important unique predictors of disability. Physical activity programs should be directed at these fitness components. [ABSTRACT FROM AUTHOR]

A model-based planning tool, integrated in an imaging system, is envisioned for CT-guided percutaneous microwave ablation. This study aims to evaluate the biophysical model performance, by comparing its prediction retrospectively with the actual ablation ground truth from a clinical dataset in liver. The biophysical model uses a simplified formulation of heat deposition on the applicator and a heat sink related to vasculature to solve the bioheat equation. A performance metric is defined to assess how the planned ablation overlaps the actual ground truth. Results demonstrate superiority of this model prediction compared to manufacturer tabulated data and a significant influence of the vasculature cooling effect. Nevertheless, vasculature shortage due to branches occlusion and applicator misalignment due to registration error between scans affects the thermal prediction. With a more accurate vasculature segmentation, occlusion risk can be estimated, whereas branches can be used as liver landmarks to improve the registration accuracy. Overall, this study emphasizes the benefit of a model-based thermal ablation solution in better planning the ablation procedures. Contrast and registration protocols must be adapted to facilitate its integration into the clinical workflow., (© 2023. Springer Nature Limited.)

Background: The Community Wise (CW) intervention applies a community-based approach to improve the physical fitness, self-management ability, loneliness, social cohesion, and well-being of older adults living in neighbourhoods characterized by lower socioeconomic status (SES)., Methods: Participants (N = 108) were recruited using several strategies, including door-to-door visits and community key peers. The study was based on a pre-test/post-test design. Outcomes were assessed through mixed methods using questionnaires, performance tests, semi-structured interviews, and focus-group sessions., Results: Results showed significant improvements on aerobic endurance and shoulder flexibility, but no significant improvements on self-management ability, social cohesion, loneliness, or well-being. Qualitative data analysis did indicate that participants experienced improvements on social connectedness with members of the group, as well as on self-management ability., Conclusion: The results of the intervention seem to depend on programme fidelity and method of assessment. Adapting the intervention and including more older adults with poor health status could lead to better outcomes in the future. This results of this study should be interpreted in light of the complexity and methodological challenges of conducting a community-based health-promotion intervention for this target group., Trail Registration: Retrospective registration., (© 2023. The Author(s).)

A model-based planning tool, integrated in an imaging system, is envisioned for CT-guided percutaneous microwave ablation. This study aims to evaluate the biophysical model performance, by comparing its prediction retrospectively with the actualablation ground truth from a clinical data set in liver. The biophysical model uses a simplified formulation of heat depositionon the applicator and a heat sink related to vasculature to solve the bioheat equation. A performance metric is defined toassess how the planned ablation overlaps the actual ground truth. Results demonstrate superiority of this model predictioncompared to manufacturer tabulated data and a significant influence of the vasculature cooling effect. Nevertheless, vasculatureshortage due to branches occlusion and applicator misalignment due to registration error between scans affects the thermalprediction. With a more accurate vasculature segmentation, occlusion risk can be estimated, whereas branches can be usedas liver landmarks to improve the registration accuracy. Overall, this study emphasizes the benefit of a model-based thermalablation solution in better planning the ablation procedures. Contrast and registration protocols must be adapted to facilitate itsintegration into the clinical workflow.

Purpose: The health perceptions of older adults with a lower socioeconomic status still seems to be unsettled. To gain more insight in these perceptions, 19 older adults were interviewed with the use of a photo-elicitation method. Methods: Participants reflected on ten photographs covering aspects of physical, social and mental health, and were also asked if and how they experience to have control over their health. Results: The results showed that the perception of health depended on the background of the participant, was experience-oriented and was mostly focused on the negative aspects of physical and mental health. Social contacts were an important contributor to well-being, especially when physical health declined. Although most participants seem hardly aware of having influence on their own health, several participants showed automatic self-management abilities. Conclusion: For participants who need more support to improve, or become more aware of their self-management abilities, interventions with an experience-oriented approach are needed.

Nocturnal leg cramps (NLC) are painful, involuntary muscle contractions that affect the quality of sleep. The aim of this study was to examine the feasibility and effectiveness of a stretching regimen in frail older adults aged over 75 years with NLC. The experimental group (n = 15) received an intervention, which they were instructed to perform three daily exercises to stretch the calves and hamstrings. After six weeks, frequency and pain intensity of NLC were both significantly decreased in the experimental group compared to the control group. A paired samples t-test reveals a statistically significant decrease in cramp frequency (t = 2.2, df 28, P = 0.04) and cramp intensity (t = 2.7, df 28, P = 0.01). Therefore, a six-week stretching regimen is likely to reduce the frequency and pain intensity of NLC in frail older adults aged over 75 years., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: Superficial tumours with deep infiltration in the upper 15 cm of the trunk cannot be treated adequately with existing hyperthermia systems. The aim of this study was to develop, characterise and evaluate a new flexible two-channel hyperthermia system (AMC-2) for tumours in this region., Materials and Methods: The two-channel AMC-2 system has two horizontally revolving and height adjustable 70 MHz waveguides. Three different interchangeable antennas with sizes 20 × 34, 15 × 34 and 8.5 × 34 cm were developed and their electrical properties were determined. The performance of the AMC-2 system was tested by measurements of the electric field distribution in a saline water filled elliptical phantom, using an electric field vector probe. Clinical feasibility was demonstrated by treatment of a melanoma in the axillary region., Results: Phantom measurements showed a good performance for all waveguides. The large reflection of the smallest antenna has to be compensated by increased forward power. Field patterns become asymmetrical when using smaller top antennas, necessitating phase corrections. The clinical application showed that tumours deeper than 4 cm can be heated adequately. A median tumour temperature of 42 °C can be reached up to 12 cm depth with adequate antenna positioning and phase-amplitude steering., Conclusions: This 70 MHz AMC-2 waveguide system is a useful addition to existing loco-regional hyperthermia equipment as it is capable of heating axillary tumours and other tumours deeper than 4 cm.

The incidence of small renal masses (SRMs) sized  <4 cm has increased over the decades (as co-findings/or due to introduction of cross sectional imaging). Currently, partial nephrectomy (PN) or watchful waiting is advised in these patients. Ultimately, 80-90% of these SRMs require surgical treatment and PN is associated with a 15% complication rate. In this aging population, with possible comorbidities and poor health condition, both PN and watchful waiting are non-ideal treatment options. This resulted in an increased need for early, non-invasive treatment strategies such as MR-guided high intensity focused ultrasound (MR-HIFU). (i) To investigate the feasibility of creating a confluent lesion in the kidney using respiratory-gated MR-HIFU under clinical conditions in a pre-clinical study and (ii) to evaluate the reproducibility of the MR-HIFU ablation strategy. Healthy pigs (n  =  10) under general anesthesia were positioned on a clinical MR-HIFU system with integrated cooling. A honeycomb pattern of seven overlapping ablation cells (4  ×  4  ×  10 mm 3 , 450 W, <30 s) was ablated successively in the cortex of the porcine kidney. Both MR thermometry and acoustic energy delivery were respiratory gated using a pencil beam navigator on the contralateral kidney. The non-perfused volume (NPV) was visualized after the last sonication by contrast-enhanced (CE) T 1 -weighted MR (T 1 w) imaging. Cell viability staining was performed to visualize the extent of necrosis., Results: a median NPV of 0.62 ml was observed on CE-T 1 w images (IQR 0.58-1.57 ml, range 0.33-2.75 ml). Cell viability staining showed a median damaged volume of 0.59 ml (IQR 0.24-1.35 ml, range 0-4.1 ml). Overlooking of the false rib, shivering of the pig, and too large depth combined with a large heat-sink effect resulted in insufficient heating in 4 cases. The NPV and necrosed volume were confluent in all cases in which an ablated volume could be observed. Our results demonstrated the feasibility of creating a confluent volume of ablated kidney cortical tissue in vivo with MR-HIFU on a clinically available system using respiratory gating and near-field cooling and showed its reproducibility.

The purpose of this study was to evaluate a novel phased array transducer design rule for therapeutic focused ultrasound applications. This design rule uses the discretized Fermat's spiral to determine the positioning of the transducer elements for a given number of elements and f-number. Using this principle, three variations of Fermat's spiral were generated, aimed at (1) grating lobe minimization, (2) side lobe minimization, and (3) an optimized element packing efficiency. For each spiral, sparse layouts using identical circular elements and fully populated layouts based on additional Voronoi tessellation were evaluated numerically. Evaluation criteria included the element size distribution, beam steering capabilities, focal plane pressure distribution, prefocal pressure distribution, and practical considerations. Finally, one Voronoi-tessellated design with a focal length and aperture diameter of 16 cm and a natural frequency of 1.3 MHz was evaluated experimentally through hydrophone measurements. The numerical evaluation showed that while sparse arrays possess superior beam steering capabilities for a given number of elements, the focal point quality and prefocal pressure distribution is substantially more favorable when using the Voronoi-tessellated designs. Beam steering was shown to be feasible with the tessellated designs for lateral deflections up to 10 mm and axial deflections up to 20 mm. The experimental evaluation showed that such a transducer is capable of inducing 40.00 MPa rarefactional and 237.50 MPa compressional peak pressure levels at 800 W instantaneous acoustic output power under free-field conditions, making the system potentially relevant for thermal ablation therapy, histotripsy applications, and shockwave-enhanced heating.

Purpose: A major complication for abdominal High Intensity Focused Ultrasound (HIFU) applications is the obstruction of the acoustic beam path by the thoracic cage, which absorbs and reflects the ultrasonic energy leading to undesired overheating of healthy tissues in the pre-focal area. Prior work has investigated the determination of optimized transducer apodization laws, which allow for a reduced rib exposure whilst (partially) restoring focal point intensity through power compensation. Although such methods provide an excellent means of reducing rib exposure, they generally increase the local energy density in the pre-focal area, which similarly can lead to undesired overheating. Therefore, this numerical study aimed at evaluating whether a novel transducer design could provide improvement for intercostal HIFU applications, in particular with respect to the pre-focal area., Methods: A combination of acoustic and thermal simulations was used to evaluate 2 mono-element transducers, 2 clinical phased array transducers, and 4 novel transducers based on Fermat's Spiral (FS), two of which were Voronoi-tessellated (VTFS). Binary apodizations were determined for the phased array transducers using a collision detection algorithm. A tissue geometry was modeled to represent an intercostal HIFU sonication in the liver at 30 and 50 mm behind the ribs, including subsequent layers of gel pad, skin, subcutaneous fat, muscle, and liver tissue. Acoustic simulations were then conducted using propagation of the angular spectrum of plane waves (ASPW). The results of these simulations were used to evaluate pre-focal intensity levels. Subsequently, a finite difference scheme based on the Pennes bioheat equation was used for thermal simulations. The results of these simulations were used to calculate both the energy density in the pre-focal skin, fat, and muscle layers, as well as the energy exposure of the ribs., Results: The acoustic simulations showed that for a sonication in a single point without beamsteering, comparing the best performing clinical phased array in this study to an equivalent VTFS transducer, the maximum intensity in the focal point was increased from 19.0 to 27.0 W/mm 2 for the sonication 30 mm behind the ribs, while the rib area exposed to ≥20 J/cm 2 was reduced from 0.88 to 0.14 cm 2 . For the sonication 50 mm behind the ribs, the maximum focal point intensity was increased from 13.4 to 21.5 W/mm 2 , while the rib area exposed to ≥40 J/cm 2 was lowered from 2.71 to 0.01 cm 2 . The thermal simulations showed that for a circular sonication cell of 4 mm diameter in the transversal plane, sonication times for sonications 30/50 mm behind the ribs were reduced from 13.9 to 8.38 s/38.2 to 17.4 s, respectively. Energy density levels in the skin for these sonications were decreased from 5.28 to 2.22/9.45 to 3.78 J/mm 2 ., Conclusions: VTFS transducers are expected to provide improvement for intercostal HIFU applications compared to currently available clinical transducers, as they reduce both the energy density in the pre-focal zone and the energy exposure of the ribs. These characteristics allow for increasing either the re-sonication rate or the treatment volume per sonication., (© 2017 American Association of Physicists in Medicine.)

Background: Up to 33% of the general population over 50 years of age are affected by nocturnal leg cramps. Currently there are no generally accepted clinical characteristics, which identify nocturnal leg cramps. This study aims to identify these clinical characteristics and to differentiate between them and the characteristics of restless leg syndrome and periodic limb disorder., Method: A systematic literature study was executed from December 2015 to May 2016. This study comprised of a systematic literature review of randomized clinical trials, observational studies on nocturnal and rest cramps of legs and other muscles, and other systematic and narrative reviews. Two researchers independently extracted literature data and analyzed this using a standardized reviewing protocol. Modified versions of the Cochrane Collaboration tools assessed the risk of bias. A Delphi study was conducted to assess agreement on the characteristics of nocturnal leg cramps., Results: After systematic and manual searches, eight randomized trials and ten observational studies were included. On the basis of these we identified seven diagnostic characteristics of nocturnal leg cramps: intense pain, period of duration from seconds to maximum 10 minutes, location in calf or foot, location seldom in thigh or hamstrings, persistent subsequent pain, sleep disruption and distress., Conclusion: The seven above characteristics will enhance recognition of the condition, and help clinicians make a clear distinction between NLC and other sleep-related musculoskeletal disorder among older adults.

Background: Previous studies demonstrated both pre-clinically and clinically the feasibility of magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) ablations in the liver. To overcome the associated problem of respiratory motion of the ablation area, general anesthesia (GA) and mechanical ventilation was used in conjunction with either respiratory-gated energy delivery or energy delivery during induced apnea. However, clinical procedures requiring GA are generally associated with increased mortality, morbidity, and complication rate compared to procedural sedation and analgesia (PSA). Furthermore, PSA is associated with faster recovery and an increased eligibility for non- and mini-invasive interventions., Methods: In this study, we investigate both in an animal model and on a small patient group the kinetics of the diaphragm during free-breathing, when a tailored remifentanil/propofol-based PSA protocol inducing partial respiratory depression is used. Subsequently, we demonstrate in an animal study the compatibility of the resulting respiratory pattern of the PSA protocol with a gated HIFU ablation in the liver by direct comparison with gated ablations conducted under GA. Wilcoxon signed-rank tests were performed for statistical analysis of non-perfused and necrosed tissue volumes. Duty cycles (ratio or percentage of the breathing cycle with the diaphragm in its resting position, such that acoustic energy delivery with MR-HIFU was allowed) were statistically compared for both GA and PSA using student's t tests., Results: In both animal and human experiments, the breathing frequency was decreased below 9/min, while maintaining stable vital functions. Furthermore an end-exhalation resting phase was induced by this PSA protocol during which the diaphragm is virtually immobile. Median non-perfused volumes, non-viable volumes based on NADH staining, and duty cycles were larger under PSA than under GA or equal., Conclusions: We conclude that MR-HIFU ablations of the liver under PSA are feasible and potentially increase the non-invasive nature of this type of intervention.

Purpose: To investigate the effect of the aqueous and fatty tissue magnetic susceptibility distribution on absolute and relative temperature measurements as obtained directly from the water/fat (w/f) frequency difference., Methods: Absolute thermometry was investigated using spherical phantoms filled with pork and margarine, which were scanned in three orthogonal orientations. To evaluate relative fat referencing, multigradient echo scans were acquired before and after heating pork tissue via high-intensity focused ultrasound (HIFU). Simulations were performed to estimate the errors that can be expected in human breast tissue., Results: The sphere experiment showed susceptibility-related errors of 8.4 °C and 0.2 °C for pork and margarine, respectively. For relative fat referencing measurements, fat showed pronounced phase changes of opposite polarity to aqueous tissue. The apparent mean temperature for a numerical breast model assumed to be 37 °C was 47.2 ± 21.6 °C. Simulations of relative fat referencing for a HIFU sonication (ΔT = 29.7 °C) yielded a maximum temperature error of 6.6 °C compared with 2.5 °C without fat referencing., Conclusion: Variations in the observed frequency difference between water and fat are largely due to variations in the w/f spatial distribution. This effect may lead to considerable errors in absolute MR thermometry. Additionally, fat referencing may exacerbate rather than correct for proton resonance frequency shift-temperature measurement errors., (© 2015 Wiley Periodicals, Inc.)

Background: Limited research has examined what is actually done in the process of care by nursing staff in long-term institutional care. The applied instruments employed different terminologies, and psychometric properties were inadequately described. This study aimed to develop and test an observational instrument to identify and examine the amount of time spent on nursing interventions in long-term institutional care using a standardized language., Methods: The Groningen Observational instrument for Long-Term Institutional Care (GO-LTIC) is based on the conceptual framework of the Nursing Interventions Classification. Developmental, validation, and reliability stages of the GO-LTIC included: 1) item generation to identify potential setting-specific interventions; 2) examining content validity with a Delphi panel resulting in relevant interventions by calculating the item content validity index; 3) testing feasibility with trained observers observing nursing assistants; and 4) calculating inter-rater reliability using (non) agreement and Cohen's kappa for the identification of interventions and an intraclass correlation coefficient for the amount of time spent on interventions. Bland-Altman plots were applied to visualize the agreement between observers. A one-sample student T-test verified if the difference between observers differed significantly from zero., Results: The final version of the GO-LTIC comprised 116 nursing interventions categorized into six domains. Substantial to almost perfect kappa's were found for interventions in the domains basic (0.67-0.92) and complex (0.70-0.94) physiological care. For the domains of behavioral, family, and health system interventions, the kappa's ranged from fair to almost perfect (0.30-1.00). Intraclass correlation coefficients for the amount of time spent on interventions ranged from fair to excellent for the physiological domains (0.48-0.99) and poor to excellent for the other domains (0.00-1.00). Bland Altman plots indicated that the clinical magnitude of differences in minutes was small. No statistical significant differences between observers (p > 0.05) were found., Conclusions: The GO-LTIC shows good content validity and acceptable inter-rater reliability to examine the amount of time spent on nursing interventions by nursing staff. This may provide managers with valuable information to make decisions about resource allocation, task allocation of nursing staff, and the examination of the costs of nursing services.

This study investigated whether an MR-guided pulsed HIFU ablation strategy could be implemented under clinical conditions, using a transducer designed for uterine fibroid ablation, to obtain an ablation rate that is sufficiently high for clinical abdominal HIFU therapy in highly perfused organs. A pulsed HIFU ablation strategy, aimed at increasing the energy absorption in the HIFU focal area by local shock wave formation in the non-linear pressure regime, was compared to an energy-equivalent continuous wave sonication strategy in the linear pressure regime. Both ablation strategies were used for transcutaneous sonication of pre-defined treatment cells in the livers of 5 pigs in vivo. Temperature evolution in both the target area as well as the pre-focal muscle layer was monitored simultaneously using MR thermometry. Local energy absorption and thermal dose volumes were shown to be increased using the pulsed ablation strategy, while preserving healthy tissue in the near field of the acoustic beam. Respiratory motion compensation of both acoustic energy delivery and MR thermometry was applied through gating based on MR navigator echoes. Histopathology showed that confluent vacuolated thermal lesions were created when the pulsed ablation strategy was used. Additionally, it was shown that the heat sink effect caused by the presence of larger vessels could be overcome. The pulsed HIFU ablation strategy achieved an ablation rate of approximately 4 ml per hour in the in vivo porcine liver, without causing undesired damage to healthy tissues in the near field.