323 research outputs found

    Multi-detector row computed tomography angiography of peripheral arterial disease

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    With the introduction of multi-detector row computed tomography (MDCT), scan speed and image quality has improved considerably. Since the longitudinal coverage is no longer a limitation, multi-detector row computed tomography angiography (MDCTA) is increasingly used to depict the peripheral arterial runoff. Hence, it is important to know the advantages and limitations of this new non-invasive alternative for the reference test, digital subtraction angiography. Optimization of the acquisition parameters and the contrast delivery is important to achieve a reliable enhancement of the entire arterial runoff in patients with peripheral arterial disease (PAD) using fast CT scanners. The purpose of this review is to discuss the different scanning and injection protocols using 4-, 16-, and 64-detector row CT scanners, to propose effective methods to evaluate and to present large data sets, to discuss its clinical value and major limitations, and to review the literature on the validity, reliability, and cost-effectiveness of multi-detector row CT in the evaluation of PAD

    Cost-effectiveness of CT angiography and perfusion imaging for delayed cerebral ischemia and vasospasm in aneurysmal subarachnoid hemorrhage

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    BACKGROUND AND PURPOSE: Delayed cerebral ischemia and vasospasm are significant complications following SAH leading to cerebral infarction, functional disability, and death. In recent years, CTA and CTP have been used to increase the detection of delayed cerebral ischemia and vasospasm. Our aim was to perform comparative-effectiveness and cost-effectiveness analyses evaluating CTA and CTP for delayed cerebral ischemia and vasospasm in aneurysmal SAH from a health care payer perspective. MATERIALS AND METHODS: We developed a decision model comparing CTA and CTP with transcranial Doppler sonography for detection of vasospasm and delayed cerebral ischemia in SAH. The clinical pathways were based on the Guidelines for the Management of Aneurysmal Subarachnoid Hemorrhage: A Guideline for Healthcare Professionals from the American Heart Association/American Stroke Association (2012). Outcome health states represented mortality and morbidity according to functional outcomes. Input probabilities of symptoms and serial test results from CTA and CTP, transcranial Doppler ultrasound, and digital subtraction angiography were directly derived from an SAH cohort by using a multinomial logistic regression model. Expected benefits, measured as quality-adjusted life years, and costs, measured in 2012 US dollars, were calculated for each imaging strategy. Univariable, multivariable, and probabilistic sensitivity analyses were performed to determine the independent and combined effect of input parameter uncertainty. RESULTS: The transcranial Doppler ultrasound strategy yielded 13.62 quality-adjusted life years at a cost of 154,719.TheCTAandCTPstrategygenerated13.89qualityāˆ’adjustedlifeyearsatacostof154,719. The CTA and CTP strategy generated 13.89 quality-adjusted life years at a cost of 147,097, resulting in a gain of 0.27 quality-adjusted life years and cost savings of $7622 over the transcranial Doppler ultrasound strategy. Univariable and multivariable sensitivity analyses indicated that results were robust to plausible input parameter uncertainty. Probabilistic sensitivity analysis results yielded 96.8% of iterations in the right lower quadrant, representing higher benefits and lower costs. CONCLUSIONS: Our model results suggest that CTA and CTP are the preferred imaging strategy in SAH, compared with transcranial Doppler ultrasound, leading to improved clinical outcomes and lower health care costs

    Microstructural brain injury in post-concussion syndrome after minor head injury

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    Introduction: After minor head injury (MHI), post-concussive symptoms commonly occur. The purpose of this study was to correlate the severity of post-concussive symptoms in MHI patients with MRI measures of microstructural brain injury, namely mean diffusivity (MD) and fractional anisotropy (FA), as well as the presence of microhaemorrhages. Methods: Twenty MHI patients and 12 healthy controls were scanned at 3Ā T using diffusion tensor imaging (DTI) and high-resolution gradient recalled echo (HRGRE) T2*-weighted sequences. One patient was excluded from the analysis because of bilateral subdural haematomas. DTI data were preprocessed using Tract Based Spatial Statistics. The resulting MD and FA images were correlated with the severity of post-concussive symptoms evaluated with the Rivermead Postconcussion Symptoms Questionnaire. The number and location of microhaemorrhages were assessed on the HRGRE T2*-weighted images. Results: Comparing patients with controls, there were no differences in MD. FA was decreased in the right temporal subcortical white matter. MD was increased in association with the severity of post-concussive symptoms in the inferior fronto-occipital fasciculus (IFO), the inferior longitudinal fasciculus and the superior longitudinal fasciculus. FA was reduced in association with the severity of post-concussive symptoms in the uncinate fasciculus, the IFO, the internal capsule and the corpus callosum, as well as in the parietal and frontal subcortical white matter. Microhaemorrhages were observed in one patient only. Conclusions: The severity of post-concussive symptoms after MHI was significantly correlated with a reduction of white matter integrity, providing evidence of microstructural brain injury as a neuropathological substrate of the post-concussion syndrome

    Managing Injuries of the Neck Trial (MINT) : design of a randomised controlled trial of treatments for whiplash associated disorders

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    Background: A substantial proportion of patients with whiplash injuries develop chronic symptoms. However, the best treatment of acute injuries to prevent long-term problems is uncertain. A stepped care treatment pathway has been proposed, in which patients are given advice and education at their initial visit to the emergency department (ED), followed by review at three weeks and physiotherapy for those with persisting symptoms. MINT is a two-stage randomised controlled trial to evaluate two components of such a pathway: 1. use of The Whiplash Book versus usual advice when patients first attend the emergency department; 2. referral to physiotherapy versus reinforcement of advice for patients with continuing symptoms at three weeks. Methods: Evaluation of the Whiplash Book versus usual advice uses a cluster randomised design in emergency departments of eight NHS Trusts. Eligible patients are identified by clinicians in participating emergency departments and are sent a study questionnaire within a week of their ED attendance. Three thousand participants will be included. Patients with persisting symptoms three weeks after their ED attendance are eligible to join an individually randomised study of physiotherapy versus reinforcement of the advice given in ED. Six hundred participants will be randomised. Follow-up is at 4, 8 and 12 months after their ED attendance. Primary outcome is the Neck Disability Index (NDI), and secondary outcomes include quality of life and time to return to work and normal activities. An economic evaluation is being carried out. Conclusion: This paper describes the protocol and operational aspects of a complex intervention trial based in NHS emergency and physiotherapy departments, evaluating two components of a stepped-care approach to the treatment of whiplash injuries. The trial uses two randomisations, with the first stage being cluster randomised and the second individually randomised

    Effectiveness of prophylactic implantation of cardioverter-defibrillators without cardiac resynchronization therapy in patients with ischaemic or non-ischaemic heart disease: a systematic review and meta-analysis

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    Aims: Much controversy exists concerning the efficacy of primary prophylactic implantable cardioverter-defibrillators (ICDs) in patients with low ejection fraction due to coronary artery disease (CAD) or dilated cardiomyopathy (DCM). This is also related to the bias created by function improving interventions added to ICD therapy, e.g. resynchronization therapy. The aim was to investigate the efficacy of ICD-only therapy in primary prevention in patients with CAD or DCM.Methods and results: Public domain databases, MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials, were searched from 1980 to 2009 for randomized clinical trials of ICD vs. conventional therapy. Two investigators independently abstracted the data. Pooled estimates were calculated using both fixed-effects and random-effects models. Eight trials were included in the final analysis (5343 patients). Implantable cardioverter-defibrillators significantly reduced the arrhythmic mortality [relative risk (RR): 0.40; 95 confidence interval (CI): 0.27-0.67] and all-cause mortality (RR: 0.73; 95 CI: 0.64-0.82). Regardless of aetiology of heart disease, ICD benefit was similar for CAD (RR: 0.67; 95 CI: 0.51-0.88) vs. DCM (RR: 0.74; 95 CI: 0.59-0.93).Conclusions: The results of this meta-analysis provide strong evidence for the beneficial effect of ICD-only therapy on the survival of patients with ischaemic or non-ischaemic heart disease, with a left ventricular ejection fraction ā‰¤35, if they are 40 days from myocardial infarction and ā‰„3 months from a coronary revascularization procedure
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