Constantinus F. Buckens
Utrecht University
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American Journal of Sports Medicine | 2010
Constantinus F. Buckens; Daniël B.F. Saris
Background Growing awareness of the biomechanical contribution of the medial patellofemoral ligament has led to an upsurge in the publication of techniques and trials dealing with reconstructive techniques, warranting a review that includes the most recent evidence. Study Design Systematic review. Methods The authors undertook a systematic electronic search and rigorous screening process to find and identify published evidence describing the outcomes of medial patellofemoral ligament reconstruction. Results Fourteen trials were included for analysis. Although they showed generally excellent outcomes for medial patellofemoral ligament reconstruction modalities, there were several recurring weaknesses. Most were small case series, many had limited follow-up, and a majority employed other adjunctive techniques besides medial patellofemoral ligament reconstruction, making it difficult to distinguish the determining factors in their outcomes. Conclusion There is limited but growing evidence that a medial patellofemoral ligament—based surgical approach to patellofemoral instability leads to excellent functional outcomes.
Annals of Surgical Oncology | 2012
Charlotte S. van Kessel; Constantinus F. Buckens; Maurice A. A. J. van den Bosch; Maarten S. van Leeuwen; Richard van Hillegersberg; Helena M. Verkooijen
BackgroundChemotherapy treatment induces parenchymal changes that potentially affect imaging of CRLM. The purpose of this meta-analysis was to provide values of diagnostic performance of magnetic resonance imaging (MRI), computed tomography (CT), fluorodeoxyglucose positron emission tomography (FDG-PET), and FDG-PET/CT for preoperative detection of colorectal liver metastases (CRLM) in patients treated with neoadjuvant chemotherapy.MethodsA comprehensive search was performed for original articles published from inception to 2011 assessing diagnostic performance of MRI, CT, FDG-PET, or FDG-PET/CT for preoperative evaluation of CRLM following chemotherapy. Intraoperative findings and/or histology were used as reference standard. For each imaging modality we calculated pooled sensitivities for patients who received neoadjuvant chemotherapy as well as for chemonaive patients, defined as number of malignant lesions detected divided by number of malignant lesions as confirmed by the reference standard.ResultsA total of 11 papers, comprising 223 patients with 906 lesions, were included. Substantial variation in study design, patient characteristics, imaging features, and reference tests was observed. Pooled sensitivity estimates of MRI, CT, FDG-PET, and FDG-PET/CT were 85.7% (69.7–94.0%), 69.9% (65.6–73.9%), 54.5% (46.7–62.1%), and 51.7% (37.8–65.4%), respectively. In chemonaive patients, sensitivity rates were 80.5% (67.0–89.4%) for CT, 81.3% (64.1–91.4%) for FDG-PET, and 71.0% (64.3–76.9%) for FDG-PET/CT. Specificity could not be calculated because of non-reporting of “true negative lesions.”ConclusionIn the neoadjuvant setting, MRI appears to be the most appropriate imaging modality for preoperative assessment of patients with CRLM. CT is the second-best diagnostic modality and should be used in the absence of MRI. Diagnostic accuracy of FDG-PET and PET-CT is strongly affected by chemotherapy.
JAMA | 2011
Onno M. Mets; Constantinus F. Buckens; Pieter Zanen; Ivana Išgum; Bram van Ginneken; Mathias Prokop; Hester A. Gietema; Jan-Willem J. Lammers; Rozemarijn Vliegenthart; Matthijs Oudkerk; Rob J. van Klaveren; Harry J. de Koning; Willem P. Th. M. Mali; Pim A. de Jong
CONTEXT Smoking is a major risk factor for both cancer and chronic obstructive pulmonary disease (COPD). Computed tomography (CT)-based lung cancer screening may provide an opportunity to detect additional individuals with COPD at an early stage. OBJECTIVE To determine whether low-dose lung cancer screening CT scans can be used to identify participants with COPD. DESIGN, SETTING, AND PATIENTS Single-center prospective cross-sectional study within an ongoing lung cancer screening trial. Prebronchodilator pulmonary function testing with inspiratory and expiratory CT on the same day was obtained from 1140 male participants between July 2007 and September 2008. Computed tomographic emphysema was defined as percentage of voxels less than -950 Hounsfield units (HU), and CT air trapping was defined as the expiratory:inspiratory ratio of mean lung density. Chronic obstructive pulmonary disease was defined as the ratio of forced expiratory volume in the first second to forced vital capacity (FEV(1)/FVC) of less than 70%. Logistic regression was used to develop a diagnostic prediction model for airflow limitation. MAIN OUTCOME MEASURES Diagnostic accuracy of COPD diagnosis using pulmonary function tests as the reference standard. RESULTS Four hundred thirty-seven participants (38%) had COPD according to lung function testing. A diagnostic model with CT emphysema, CT air trapping, body mass index, pack-years, and smoking status corrected for overoptimism (internal validation) yielded an area under the receiver operating characteristic curve of 0.83 (95% CI, 0.81-0.86). Using the point of optimal accuracy, the model identified 274 participants with COPD with 85 false-positives, a sensitivity of 63% (95% CI, 58%-67%), specificity of 88% (95% CI, 85%-90%), positive predictive value of 76% (95% CI, 72%-81%); and negative predictive value of 79% (95% CI, 76%-82%). The diagnostic model showed an area under the receiver operating characteristic curve of 0.87 (95% CI, 0.86-0.88) for participants with symptoms and 0.78 (95% CI, 0.76-0.80) for those without symptoms. CONCLUSION Among men who are current and former heavy smokers, low-dose inspiratory and expiratory CT scans obtained for lung cancer screening can identify participants with COPD, with a sensitivity of 63% and a specificity of 88%.
Current Opinion in Allergy and Clinical Immunology | 2015
Judith L. Thijs; Todor Krastev; Stephan Weidinger; Constantinus F. Buckens; Marjolein S. de Bruin-Weller; Carla A.F.M. Bruijnzeel-Koomen; Carsten Flohr; DirkJan Hijnen
Purpose of reviewA large number of studies investigating the correlation between severity of atopic dermatitis and various biomarkers have been published over the past decades. The aim of this review was to identify, evaluate and synthesize the evidence examining the correlation of biomarkers with disease severity in atopic dermatitis patients, something that has not been performed previously. Recent findingsThree electronic databases were systematically searched and relevant studies were selected for inclusion. A total of 222 articles, reporting on 115 different biomarkers in 30 063 patients, were critically appraised. Studies were divided into two main groups. The first group consisted of longitudinal randomized controlled trials and cohort studies, which reported measurements at multiple time points. The second contained cross-sectional studies that reported only one measurement per patient. Out of 222 articles, 108 articles reported sufficient data for meta-analysis. Only four biomarkers were eligible for meta-analysis in the longitudinal group, and nine in the cross-sectional group. SummarySerum thymus and activation-regulated chemokine (TARC) was found to be the most reliable biomarker studied, showing pooled correlation coefficients of 0.60 (95% CI 0.48–0.70) and 0.64 (95% CI 0.57–0.70) in longitudinal and cross-sectional studies, respectively. Additional biomarkers that could prove useful but require additional research include serum cutaneous T-cell attracting chemokine (CTACK), sE-selectin, macrophage-derived chemokine (MDC), lactate dehydrogenase (LDH) and interleukin (IL)-18.
Jacc-cardiovascular Imaging | 2013
Onno M. Mets; Rozemarijn Vliegenthart; Martijn J. A. Gondrie; Max A. Viergever; Matthijs Oudkerk; Harry J. de Koning; Willem P. Th. M. Mali; Mathias Prokop; Rob J. van Klaveren; Yolanda van der Graaf; Constantinus F. Buckens; Pieter Zanen; Jan-Willem J. Lammers; Harry J.M. Groen; Ivana Išgum; Pim A. de Jong
OBJECTIVES The aim of this study was to derivate and validate a prediction model for cardiovascular events based on quantification of coronary and aortic calcium volume in lung cancer screening chest computed tomography (CT). BACKGROUND CT-based lung cancer screening in heavy smokers is a very timely topic. Given that the heavily smoking screening population is also at risk for cardiovascular disease, CT-based screening may provide the opportunity to additionally identify participants at high cardiovascular risk. METHODS Inspiratory screening CT of the chest was obtained in 3,648 screening participants. Next, smoking characteristics, patient demographics, and physician-diagnosed cardiovascular events were collected from 10 years before the screening CT (i.e., cardiovascular history) until 3 years after the screening CT (i.e., follow-up time). Cox proportional hazards analysis was used to derivate and validate a prediction model for cardiovascular risk. Age, smoking status, smoking history, and cardiovascular history, together with automatically quantified coronary and aortic calcium volume from the screening CT, were included as independent predictors. The primary outcome measure was the discriminatory value of the model. RESULTS Incident cardiovascular events occurred in 145 of 1,834 males (derivation cohort) and 118 of 1,725 males and 2 of 89 females (validation cohort). The model showed good discrimination in the validation cohort with a C-statistic of 0.71 (95% confidence interval: 0.67 to 0.76). When high risk was defined as a 3-year risk of 6% and higher, 589 of 1,725 males were regarded as high risk and 72 of 118 of all events were correctly predicted by the model. CONCLUSIONS Quantification of coronary and aortic calcium volumes in lung cancer screening CT images-information that is readily available-can be used to predict cardiovascular risk. Such an approach might prove useful in the reduction of cardiovascular morbidity and mortality and may enhance the cost-effectiveness of CT-based screening in heavy smokers.
International Journal of Cardiology | 2013
Tim Luijkx; Birgitta K. Velthuis; Frank J.G. Backx; Constantinus F. Buckens; Niek H. Prakken; Rienk Rienks; Willem P. Th. M. Mali; Maarten J. Cramer
BACKGROUND Uncertainty remains about possible cardiac adaptation to resistance training. Androgenic anabolic steroids (AAS) use plays a potential role and may have adverse cardiovascular effects. OBJECTIVE To elucidate the effect of resistance training and of AAS-use on cardiac dimensions and function. PARTICIPANTS Cardiac magnetic resonance (CMR) were performed in 156 male subjects aged 18-40 years: 52 non-athletes (maximum of 3 exercise hours/week), 52 strength-endurance (high dynamic-high static, HD-HS) athletes and 52 strength (low dynamic-high static, LD-HS) trained athletes (athletes ≥ 6 exercise hours/week). 28 LD-HS athletes denied and 24 admitted to AAS use for an average duration of 5 years (range 3 months-20 years). RESULTS No significant differences were found between non-athletes and non-AAS-using LD-HS athletes. AAS-using LD-HS athletes had significantly larger LV and RV volumes and LV wall mass than non-AAS-using LD-HS athletes, but lower than HD-HS athletes. In comparison to all other groups AAS-using LD-HS athletes showed lower ejection fractions of both ventricles (LV/RV EF 51/48% versus 55-57/51-52%) and lower E/A ratios (LV/RV 1.5/1.2 versus 1.9-2.0/1.4-1.5) as an indirect measure of diastolic function. Linear regression models demonstrated a significant effect of AAS-use on LV EDV, LV EDM, systolic function and mitral valve E/A ratio (all ANOVA-tests p<0.05). CONCLUSIONS Strength athletes who use AAS show significantly different cardiac dimensions and biventricular systolic dysfunction and impaired ventricular inflow as compared to non-athletes and non-AAS-using strength athletes. Increased ventricular volume and mass did not exceed that of strength-endurance athletes. These findings may help raise awareness of the consequences of AAS use.
Respiratory Research | 2013
Onno M. Mets; Michael Schmidt; Constantinus F. Buckens; Martijn J. A. Gondrie; Ivana Išgum; Matthijs Oudkerk; Rozemarijn Vliegenthart; Harry J. de Koning; Carlijn M. van der Aalst; Mathias Prokop; Jan-Willem J. Lammers; Pieter Zanen; Firdaus A. A. Mohamed Hoesein; Willem PThM Mali; Bram van Ginneken; Eva M. van Rikxoort; Pim A. de Jong
BackgroundBeyond lung cancer, screening CT contains additional information on other smoking related diseases (e.g. chronic obstructive pulmonary disease, COPD). Since pulmonary function testing is not regularly incorporated in lung cancer screening, imaging biomarkers for COPD are likely to provide important surrogate measures for disease evaluation. Therefore, this study aims to determine the independent diagnostic value of CT emphysema, CT air trapping and CT bronchial wall thickness for COPD in low-dose screening CT scans.MethodsPrebronchodilator spirometry and volumetric inspiratory and expiratory chest CT were obtained on the same day in 1140 male lung cancer screening participants. Emphysema, air trapping and bronchial wall thickness were automatically quantified in the CT scans. Logistic regression analysis was performed to derivate a model to diagnose COPD. The model was internally validated using bootstrapping techniques.ResultsEach of the three CT biomarkers independently contributed diagnostic value for COPD, additional to age, body mass index, smoking history and smoking status. The diagnostic model that included all three CT biomarkers had a sensitivity and specificity of 73.2% and 88.%, respectively. The positive and negative predictive value were 80.2% and 84.2%, respectively. Of all participants, 82.8% was assigned the correct status. The C-statistic was 0.87, and the Net Reclassification Index compared to a model without any CT biomarkers was 44.4%. However, the added value of the expiratory CT data was limited, with an increase in Net Reclassification Index of 4.5% compared to a model with only inspiratory CT data.ConclusionQuantitatively assessed CT emphysema, air trapping and bronchial wall thickness each contain independent diagnostic information for COPD, and these imaging biomarkers might prove useful in the absence of lung function testing and may influence lung cancer screening strategy. Inspiratory CT biomarkers alone may be sufficient to identify patients with COPD in lung cancer screening setting.
British Journal of Sports Medicine | 2012
Tim Luijkx; Maarten J. Cramer; Niek H. Prakken; Constantinus F. Buckens; Arend Mosterd; Rienk Rienks; Frank J.G. Backx; Willem P. Th. M. Mali; Birgitta K. Velthuis
Background Physiological cardiac adaptation in athletes is influenced by body surface area, gender, age, training intensity and sport type. This study assesses the influence of sport category and provides a physiological reference for sport category and gender. Methods Three hundred and eighty-one subjects (mean age 25±5 years, range 18 to 39 years; 61% men) underwent cardiac MRI and ECG: 114 healthy non-athletes (≤3 training h/week) and 267 healthy elite athletes (mean 17±6.6 training h/week). Athletes performed low-dynamic high-static (LD-HS, n=42), high-dynamic low-static (HD-LS, n=144) or high-dynamic high-static sports (HD-HS, n=81). Results Left ventricular (LV) end-diastolic volume (EDV) index (ml/m2) for non-athletes/LD-HS/HD-LS/HD-HS, respectively, was 101/107/122/129 in men and 90/103/106/111 in women. LV end-diastolic mass (EDM) index (g/m2) for non-athletes/LD-HS/HD-LS/HD-HS was, respectively, 47/49/57/69 for men and 34/38/42/51 for women. Left or right ventricular EDV ratios were alike in all groups. LV EDV/EDM ratios were similar in non-athletes/LD-HS/HD-LS athletes, and only lower in HD-HS athletes, disproving selective ventricular wall thickening in LD-HS athletes. Multivariate linear regression demonstrated HD-LS and HD-HS sport category coefficients (p<0.01) larger than those of training hours, gender and age (LV EDV/EDM coefficients for sport category LD-HS 6/0.75, HD-LS 16/7, HD-HS 21/17). ECG abnormalities were most frequent in HD-HS athletes and in male subjects. Conclusions This study demonstrates a balanced cardiac adaptation with preserved ratios of LV/right ventricular volume (in all sport categories) and LV volume/wall mass (in LD-HS and HD-LS sports). Sport category has a strong impact on cardiac adaptation. HD-HS sports show the largest changes, whereas LD-HS sports show dimensions similar to non-athletes.
Journal of Neurosurgery | 2010
Agnita Stadhouder; Constantinus F. Buckens; Herman R. Holtslag; F. Cumhur Oner
OBJECT Valid outcome assessment tools specific for spinal trauma patients are necessary to establish the efficacy of different treatment options. So far, no validated specific outcome measures are available for this patient population. The purpose of this study was to assess the current state of outcome measurement in spinal trauma patients and to address the question of whether this group is adequately served by current disease-specific and generic health-related quality-of-life instruments. METHODS A number of widely used outcome measures deemed most appropriate were reviewed, and their applicability to spinal trauma outcome discussed. An overview of recent movements in the theoretical foundations of outcome assessment, as it pertains to spinal trauma patients has been attempted, along with a discussion of domains important for spinal trauma. Commonly used outcome measures that are recommended for use in trauma patients were reviewed from the perspective of spinal trauma. The authors further sought to select a number of spine trauma-relevant domains from the WHOs comprehensive International Classification of Functioning, Disability and Health (ICF) as a benchmark for assessing the content coverage of the commonly used outcome measurements reviewed. RESULTS The study showed that there are no psychometrically validated outcome measurements for the spinal trauma population and there are no commonly used outcome measures that provide adequate content coverage for spinal trauma domains. CONCLUSIONS Spinal trauma patients are currently followed either as a subset of the polytrauma population in the acute and early postacute setting or as a subset of neurological injury in the long-term revalidation medicine setting.
Journal of Bone and Mineral Research | 2014
Constantinus F. Buckens; Pim A. de Jong; Willem P. Th. M. Mali; Harald J. J. Verhaar; Yolanda van der Graaf; Helena M. Verkooijen
Subclinical or undiagnosed vertebral fractures on routine chest computed tomography (CT) may be useful for detecting patients at increased risk of future hip fractures who might benefit from preventive interventions. We investigated whether prevalent vertebral fractures on routine chest CT are associated with future hip fractures. From a source population of 5679 patients ≥40 years old undergoing chest CT in one of three Dutch hospitals between 2002 and 2005, patients hospitalized for hip fractures (n = 149) during a median follow‐up of 4.4 years were identified. Following a case‐cohort design, a random sample of 576 patients was drawn from the source population and added to the cases. In this group, the presence and severity of vertebral fractures was determined using semiquantitative vertebral fracture assessment and multivariate case‐cohort appropriate Cox modeling. We found that cases were older (69 versus 63 years) and more often female (48% versus 38%) than the source population. Compared with those with no fracture, patients with any vertebral fracture had triple the risk of future hip fracture (age‐ and gender‐adjusted hazard ratio [HR] = 3.1, 95% confidence interval [CI] 2.1–4.7). This HR rose to 3.8 (CI 2.6–5.6) if mild fractures were discounted. Future fracture risk increased significantly with increasing severity of vertebral fracture status: from mild (HR = 2.4, CI 1.5–3.7) and moderate (HR = 4.8, CI 2.5–9.2) to severe (HR = 6.7, CI 2.9–15.5). The same was true for having higher cumulative fracture grades: 1 to 3 (HR = 2.7, CI 1.8–4.1), 4 to 6 (HR = 4.8, CI 2.2–10.5), or ≥7 (HR = 11.2, CI 3.7–34.6). In conclusion, prevalent vertebral fractures on routine clinical chest CT are associated with future hip fracture risk.