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30 result(s) for "Mullender, Margriet G"
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Quantitative MRI in early intervertebral disc degeneration: T1rho correlates better than T2 and ADC with biomechanics, histology and matrix content
Low-back pain (LBP) has been correlated to the presence of intervertebral disc (IVD) degeneration on T2-weighted (T2w) MRI. It remains challenging, however, to accurately stage degenerative disc disease (DDD) based on T2w MRI and measurements of IVD height, particularly for early DDD. Several quantitative MRI techniques have been introduced to detect changes in matrix composition signifying early DDD. In this study, we correlated quantitative T2, T1rho and Apparent Diffusion Coefficient (ADC) values to disc mechanical behavior and gold standard early DDD markers in a graded degenerated lumbar IVD caprine model, to assess their potential for early DDD detection. Lumbar caprine IVDs were injected with either 0.25 U/ml or 0.5 U/ml Chondroïtinase ABC (Cabc) to trigger early DDD-like degeneration. Injection with phosphate-buffered saline (PBS) served as control. IVDs were cultured in a bioreactor for 20 days under axial physiological loading. High-resolution 9.4 T MR images were obtained prior to intervention and after culture. Quantitative MR results were correlated to recovery behavior, histological degeneration grading, and the content of glycosaminoglycans (GAGs) and water. Cabc-injected IVDs showed aberrancies in biomechanics and loss of GAGs without changes in water-content. All MR sequences detected changes in matrix composition, with T1rho showing largest changes pre-to-post in the nucleus, and significantly more than T2 and ADC. Histologically, degeneration due to Cabc injection was mild. T1rho nucleus values correlated strongest with altered biomechanics, histological degeneration score, and loss of GAGs. T2- and T1rho quantitative MR-mapping detected early DDD changes. T1rho nucleus values correlated better than T2 and ADC with biomechanical, histological, and GAG changes. Clinical implementation of quantitative MRI, T1rho particularly, could aid in distinguishing DDD more reliably at an earlier stage in the degenerative process.
International phase I study protocol to develop a patient-reported outcome measure for adolescents and adults receiving gender-affirming treatments (the GENDER-Q)
IntroductionA critical barrier to outcome assessment in gender-affirming healthcare is the lack of a specific patient-reported outcome measure (PROM). This phase I protocol describes an international collaboration between investigators in Canada, Denmark, the Netherlands and the USA who have coalesced to develop a new PROM (ie, the GENDER-Q) to evaluate outcomes of psychological, hormonal and surgical gender-affirming treatments.Methods and analysisThis phase I study uses an interpretive description approach. Participants aged 16 years and older seeking any form of gender-affirming treatments in centres located in Canada, Denmark, the Netherlands and the USA will be invited to take part in qualitative interviews. Participants will review BREAST-Q and FACE-Q scales hypothesised to contain content relevant to specific gender-affirming treatments. Interviews will elicit new concepts for additional scale development. Each interview will be digitally recorded, transcribed and coded. The main outcome of this phase I study will be the development of a conceptual framework and set of scales to measure outcomes important to evaluating gender-affirming treatments. To this end, analysis will be used to add/drop/revise items of existing scales to achieve content validity. For new concepts, coding will assign top-level domains and themes/subthemes to participant quotes. Codes will be used to develop an item pool to inform scale development. Draft scales will be shown to transgender and gender diverse persons and experts to obtain feedback that will be used to refine and finalise the scales. The field-test version of the GENDER-Q will be translated by following rigorous methods to prepare for the international field-test study.Ethics and disseminationThis study is coordinated at McMaster University (Canada). Ethics board approval was received from the Hamilton Integrated Ethics Board (Canada), the Medical Ethical Committee at VUmc (The Netherlands) and Advarra (USA). Findings will be published in peer-reviewed journals and presented at national and international conferences and meetings.
Dynamic and Static Overloading Induce Early Degenerative Processes in Caprine Lumbar Intervertebral Discs
Mechanical overloading of the spine is associated with low back pain and intervertebral disc (IVD) degeneration. How excessive loading elicits degenerative changes in the IVD is poorly understood. Comprehensive knowledge of the interaction between mechanical loading, cell responses and changes in the extracellular matrix of the disc is needed in order to successfully intervene in this process. The purpose of the current study was to investigate whether dynamic and static overloading affect caprine lumbar discs differently and what mechanisms lead to mechanically induced IVD degeneration. Lumbar caprine IVDs (n = 175) were cultured 7, 14 and 21 days under simulated-physiological loading (control), high dynamic or high static loading. Axial deformation and stiffness were continuously measured. Cell viability, cell density, and gene expression were assessed in the nucleus, inner- and outer annulus. The extracellular matrix (ECM) was analyzed for water, glycosaminoglycan and collagen content. IVD height loss and changes in axial deformation were gradual with dynamic and acute with static overloading. Dynamic overloading caused cell death in all IVD regions, whereas static overloading mostly affected the outer annulus. IVDs expression of catabolic and inflammation-related genes was up-regulated directly, whereas loss of water and glycosaminoglycan were significant only after 21 days. Static and dynamic overloading both induced pathological changes to caprine lumbar IVDs within 21 days. The mechanism by which they inflict biomechanical, cellular, and extracellular changes to the nucleus and annulus differed. The described cascades provide leads for the development of new pharmacological and rehabilitative therapies to halt the progression of DDD.
A pragmatic approach for implementation of value-based healthcare in Amsterdam UMC, the Netherlands
Background The emphasis on implementation of value-based healthcare (VBHC) has increased in the Dutch healthcare system. Yet, the translation of the theoretical principles of VBHC towards actual implementation in daily practice has been rarely described. Our aim is to present a pragmatic step-by-step approach for VBHC implementation, developed and applied in Amsterdam UMC, to share our key elements. The approach may inspire others and can be used as a template for implementing VBHC principles in other hospitals. Methods The local approach is developed in a major academic hospital in the Netherlands, based at two locations with 15,000 employees in total. Experience-based co-design is used, building on our learning experiences from implementing VBHC for 14 specific patient groups. The described steps and activities devolved from iterative and participative co-design sessions with various experienced stakeholders involved in the implementation of one or more VBHC pathways. Results The approach includes five phases; preparation, design (team introduction, outcome selection, action agenda), building (outcome set integration in daily practice), implementation (training, outcome registration and implementation) and the continuous improvement cycle. We described two cases for illustration of the approach; the Cleft Lip and Palate and the Chronic Kidney Disease patient groups. For a good start, involvement of a clinical leader as driving force, ensuring participation of patient representatives and sufficient resources are needed. Conclusion We have experienced that several defining features of the development and implementation of this approach may have contributed to its completeness and applicability. Key elements for success have been organisational readiness and clinical leadership. In conclusion, the approach has provided a first step towards VBHC in our hospital. Further research is needed for evaluation of its effectiveness including impact on value for patients.
Static axial overloading primes lumbar caprine intervertebral discs for posterior herniation
Lumbar hernias occur mostly in the posterolateral region of IVDs and mechanical loading is an important risk factor. Studies show that dynamic and static overloading affect the nucleus and annulus of the IVD differently. We hypothesize there is also variance in the effect of overloading on the IVD's anterior, lateral and posterior annulus, which could explain the predilection of herniations in the posterolateral region. We assessed the regional mechanical and cellular responses of lumbar caprine discs to dynamic and static overloading. IVDs (n = 125) were cultured in a bioreactor and subjected to simulated-physiological loading (SPL), high dynamic (HD), or high static (HS) overloading. The effect of loading was determined in five disc regions: nucleus, inner-annulus and anterior, lateral and posterior outer-annulus. IVD height loss and external pressure transfer during loading were measured, cell viability was mapped and quantified, and matrix integrity was assessed. During culture, overloaded IVDs lost a significant amount of height, yet the distribution of axial pressure remained unchanged. HD loading caused cell death and disruption of matrix in all IVD regions, whereas HS loading particularly affected cell viability and matrix integrity in the posterior region of the outer annulus. Axial overloading is detrimental to the lumbar IVD. Static overloading affects the posterior annulus more strongly, while the nucleus is relatively spared. Hence, static overloading predisposes the disc for posterior herniation. These findings could have implications for working conditions, in particular of sedentary occupations, and the design of interventions aimed at prevention and treatment of early intervertebral disc degeneration.
Simulated-Physiological Loading Conditions Preserve Biological and Mechanical Properties of Caprine Lumbar Intervertebral Discs in Ex Vivo Culture
Low-back pain (LBP) is a common medical complaint and associated with high societal costs. Degeneration of the intervertebral disc (IVD) is assumed to be an important causal factor of LBP. IVDs are continuously mechanically loaded and both positive and negative effects have been attributed to different loading conditions.In order to study mechanical loading effects, degeneration-associated processes and/or potential regenerative therapies in IVDs, it is imperative to maintain the IVDs' structural integrity. While in vivo models provide comprehensive insight in IVD biology, an accompanying organ culture model can focus on a single factor, such as loading and may serve as a prescreening model to reduce life animal testing. In the current study we examined the feasibility of organ culture of caprine lumbar discs, with the hypothesis that a simulated-physiological load will optimally preserve IVD properties.Lumbar caprine IVDs (n = 175) were cultured in a bioreactor up to 21 days either without load, low dynamic load (LDL), or with simulated-physiological load (SPL). IVD stiffness was calculated from measurements of IVD loading and displacement. IVD nucleus, inner- and outer annulus were assessed for cell viability, cell density and gene expression. The extracellular matrix (ECM) was analyzed for water, glycosaminoglycan and total collagen content.IVD biomechanical properties did not change significantly with loading conditions. With SPL, cell viability, cell density and gene expression were preserved up to 21 days. Both unloaded and LDL resulted in decreased cell viability, cell density and significant changes in gene expression, yet no differences in ECM content were observed in any group.In conclusion, simulated-physiological loading preserved the native properties of caprine IVDs during a 21-day culture period. The characterization of caprine IVD response to culture in the LDCS under SPL conditions paves the way for controlled analysis of degeneration- and regeneration-associated processes in the future.
International study to develop a patient-reported outcome measure to evaluate outcomes of gender-affirming care - the GENDER-Q
Background To meaningfully understand outcomes of gender-affirming care, patient-reported outcome measures (PROMs) that are grounded in what matters to individuals seeking care are urgently needed. The objective of this study was to develop a comprehensive PROM to assess outcomes of gender-affirming care in clinical practice, research, and quality initiatives (the GENDER-Q). Methods Internationally established guidelines for PROM development were used to create a field test version of the GENDER-Q. In-depth interviews were conducted from December 2018 to March 2020 with youth and adults aged 16 years and older who were seeking or had received gender-affirming care at outpatient clinics providing gender-affirming care located within tertiary care centers or communities in Canada, Denmark, the Netherlands or the US. Data were analyzed and used to develop a conceptual framework and an item pool, which was used to develop preliminary scales. Between February 2021 to November 2021, iterative feedback was sought from clinicians and patient participants on the scales and used to refine or develop new scales. The revised scales were pilot-tested using a crowd-sourcing platform between February 2022 and April 2022. Results Data from interviews with 84 participants (aged 34 ± 14 years) resulted in a conceptual framework of the GENDER-Q with 13 domains measuring health-related quality of life, sexual, urination, gender practices, voice, hair, face and neck, body, breasts, genital feminization, chest, genital masculinization, and experience of care. Preliminary versions of 44 scales were developed covering most concepts in the conceptual framework. Iterative feedback was obtained from clinician experts (4 to 37 experts per scale; response rate, 67%) and 7–14 patient participants (depending on scale). All scales were refined, and 15 new scales were developed, resulting in 55 scales in the field test version of the GENDER-Q. In total, 601 transgender and gender diverse (TGD) people (aged 25 ± 6 years) participated in the pilot field test and the data were used to make changes to the field test survey. Conclusion The GENDER-Q was developed using extensive input from TGD individuals and clinician experts and represents the most comprehensive set of independently functioning scales that are available to date. An international field test of the GENDER-Q was completed in 2024 and the GENDER-Q is available for use in patient care, clinical research and quality improvement efforts.
Impact of short-term reconstructive surgical missions: a systematic review
IntroductionShort-term missions providing patients in low-income countries with reconstructive surgery are often criticised because evidence of their value is lacking. This study aims to assess the effectiveness of short-term reconstructive surgical missions in low-income and middle-income countries.MethodsA systematic review was conducted according to PRISMA guidelines. We searched five medical databases from inception up to 2 July 2018. Original studies of short-term reconstructive surgical missions were included, which reported data on patient safety measurements, health gains of individual patients and sustainability. Data were combined to generate overall outcomes, including overall complication rates.ResultsOf 1662 identified studies, 41 met full inclusion criteria, which included 48 546 patients. The overall study quality according to Oxford CEBM and GRADE was low. Ten studies reported a minimum of 6 months’ follow-up, showing a follow-up rate of 56.0% and a complication rate of 22.3%. Twelve studies that did not report on duration or follow-up rate reported a complication rate of 1.2%. Fifteen out of 20 studies (75%) that reported on follow-up also reported on sustainable characteristics.ConclusionsEvidence on the patient outcomes of reconstructive surgical missions is scarce and of limited quality. Higher complication rates were reported in studies which explicitly mentioned the duration and rate of follow-up. Studies with a low follow-up quality might be under-reporting complication rates and overestimating the positive impact of missions. This review indicates that missions should develop towards sustainable partnerships. These partnerships should provide quality aftercare, perform outcome research and build the surgical capacity of local healthcare systems.PROSPERO registration numberCRD42018099285.
Labiaplasty: motivation, techniques, and ethics
Labiaplasty (also known as labia minora reduction) is attracting increasing attention in the media and in online forums. Controversy exists among health-care professionals on how to manage a request for this surgery. Furthermore, the indications for and outcomes of labiaplasty have not yet been systematically assessed, and long-term outcomes have not yet been reported. Labia minora hypertrophy is defined as enlargement of the labia minora; however, the natural variation of labia minora size has scarcely been studied, with only one study suggesting objective criteria. Perception of the 'normal' appearance of labia minora is influenced by culture, exposure to idealized photographs in media, health-care professionals' opinions, and family, friends, and sexual partners (although this influence has not been substantiated by research). The desire for labiaplasty is predominantly based on dissatisfaction with genital appearance and not on functional complaints. Most health-care professionals believe that women seeking labiaplasty should be referred to a psychiatrist or psychologist for consultation before surgery, although whether counselling and education are effective at alleviating dissatisfaction or a low genital self-esteem is not clear. As the nature of patient motivation for this type of surgery is often psychological, counselling and education could be useful in reducing the demand for labiaplasty. However, current studies on surgical technique and outcomes include few patients, therefore, evidence on the results of different labiaplasty techniques and patient satisfaction is inconclusive. Further research is required to assess the value of this treatment and the appropriate indications for it. Improved understanding as to why women seek this treatment is needed and whether conservative treatments (such as counselling) are effective. Furthermore, systematic assessment of the surgical and patient-reported outcomes of labiaplasty is needed to assess whether it is safe and effective. Moreover, understanding the effect of cultural trends, for example, the way in which many women in Western society see any exception to the ideal body as a problem, will be insightful.
Two-stage implant-based breast reconstruction compared with immediate one-stage implant-based breast reconstruction augmented with an acellular dermal matrix: an open-label, phase 4, multicentre, randomised, controlled trial
The evidence justifying the use of acellular dermal matrices (ADMs) in implant-based breast reconstruction (IBBR) is limited. We did a prospective randomised trial to compare the safety of IBBR with an ADM immediately after mastectomy with that of two-stage IBBR. We did an open-label, randomised, controlled trial in eight hospitals in the Netherlands. Eligible women were older than 18 years with breast carcinoma or a gene mutation linked with breast cancer who intended to undergo skin-sparing mastectomy and immediate IBBR. Randomisation was done electronically, stratified per centre and in blocks of ten to achieve roughly balanced groups. Women were assigned to undergo one-stage IBBR with ADM (Strattice, LifeCell, Branchburg, NJ, USA) or two-stage IBBR. The primary endpoint was quality of life and safety was assessed by the occurrence of adverse outcomes. Analyses were done per protocol with logistic regression and generalised estimating equations. This study is registered at Nederlands Trial Register, number NTR5446. 142 women were enrolled between April 14, 2013, and May 29, 2015, of whom 59 (91 breasts) in the one-stage IBBR with ADM group and 62 (92 breasts) in the two-stage IBBR group were included in analyses. One-stage IBBR with ADM was associated with significantly higher risk per breast of surgical complications (crude odds ratio 3·81, 95% CI 2·67–5·43, p<0·001), reoperation (3·38, 2·10–5·45, p<0·001), and removal of implant, ADM, or both (8·80, 8·24–9·40, p<0·001) than two-stage IBBR. Severe (grade 3) adverse events occurred in 26 (29%) of 91 breasts in the one-stage IBBR with ADM group and in five (5%) of 92 in the two-stage IBBR group. The frequency of mild to moderate adverse events was similar in the two groups. Immediate one-stage IBBR with ADM was associated with adverse events and should be considered very carefully. Understanding of selection of patients, risk factors, and surgical and postsurgical procedures needs to be improved. Pink Ribbon, Nuts-Ohra, and LifeCell.