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1.

Objective

Phlebolymphedema (chronic venous insufficiency-related lymphedema) is a common and costly condition. Nevertheless, there is a dearth of evidence comparing phlebolymphedema therapeutic interventions. This study sought to examine the medical resource utilization and phlebolymphedema-related cost associated with Flexitouch (FLX; Tactile Medical, Minneapolis, Minn) advanced pneumatic compression devices (APCDs) relative to conservative therapy (CONS) alone, simple pneumatic compression devices (SPCDs), and other APCDs in a representative U.S. population of phlebolymphedema patients.

Methods

This was a longitudinal matched case-control analysis of deidentified private insurance claims. The study used administrative claims data from Blue Health Intelligence for the complete years 2012 through 2016. Patients were continuously enrolled for at least 18 months, diagnosed with phlebolymphedema, and received at least one claim for CONS either alone or in addition to pneumatic compression (SPCDs or APCDs). The main outcomes included direct phlebolymphedema- and sequelae-related medical resource utilization and costs.

Results

After case matching, the study included 86 patients on CONS (87 on FLX), 34 on SPCDs (23 on FLX), and 69 on other APCDs (67 on FLX). Compared with CONS, FLX was associated with 69% lower per patient per year total phlebolymphedema- and sequelae-related costs net of any pneumatic compression device-related costs ($3839 vs $12,253; P = .001). This was driven by 59% fewer mean annual hospitalizations (0.13 vs 0.32; P < .001) corresponding to 82% lower inpatient costs and 55% lower outpatient hospital costs. FLX was also associated with 52% lower outpatient physical therapy and occupational therapy costs and 56% lower other outpatient-related costs. Compared with SPCDs, FLX was associated with 85% lower total costs ($1153 vs $7449; P = .008) driven by 93% lower inpatient costs ($297 vs $4215; P = .002), 84% lower outpatient hospital costs ($368 vs $2347; P = .020), and 85% lower other outpatient-related costs ($353 vs $2313; P = .023). Compared with APCDs, FLX was associated with 53% lower total costs ($3973 vs $8436; P = .032) because of lower outpatient costs and lower rates of cellulitis (22.4% vs 44.9% of patients; P = .02).

Conclusions

This analysis indicates significant benefits attributable to FLX compared with alternative compression therapies that can help reduce the notable economic burden of phlebolymphedema.  相似文献   
2.

Objective

Arteriovenous fistulas created in patients with chronic kidney disease often lose patency and fail to become usable. This prospective trial evaluated the efficacy of vonapanitase, a recombinant human elastase, in promoting radiocephalic fistula patency and use for hemodialysis.

Methods

PATENCY-1 was a double-blind, placebo-controlled trial that enrolled 349 patients on or approaching hemodialysis and being evaluated for radiocephalic arteriovenous fistula creation. Of these, 313 were randomized and 311 treated. Patients were assigned to vonapanitase (n = 210) or placebo (n = 103). The study drug solution was applied topically to the artery and vein for 10 minutes immediately after fistula creation. The primary and secondary end points were primary patency (time to first thrombosis or corrective procedure) and secondary patency (time to abandonment). Tertiary end points included use of the fistula for hemodialysis, fistula maturation by ultrasound, and procedure rates.

Results

The Kaplan-Meier estimates of 12-month primary patency were 42% (95% confidence interval [CI], 35-49) and 31% (95% CI, 21-42) for vonapanitase and placebo (P = .25). The Kaplan-Meier estimates of 12-month secondary patency were 74% (95% CI, 68-80) and 61% (95% CI, 51-71) for vonapanitase and placebo (P = .048). The proportions of vonapanitase and placebo patients were 39% and 25% (P = .035) with unassisted use for hemodialysis and 64% and 44% (P = .006) with unassisted plus assisted use.

Conclusions

Vonapanitase treatment did not significantly improve primary patency but was associated with increased secondary patency and use for hemodialysis. Further research is needed to evaluate these end points.  相似文献   
3.
Gain of chromosome 1q (+1q) is one of the most common recurrent cytogenetic abnormalities in multiple myeloma (MM), occurring in approximately 40% of newly diagnosed cases. Although it is often considered a poor prognostic marker in MM, +1q has not been uniformly adopted as a high-risk cytogenetic abnormality in guidelines. Controversy exists regarding the importance of copy number, as well as whether +1q is itself a driver of poor outcomes or merely a common passenger genetic abnormality in biologically unstable disease. Although the identification of a clear pathogenic mechanism from +1q remains elusive, many genes at the 1q21 locus have been proposed to cause early progression and resistance to anti-myeloma therapy. The plethora of potential drivers suggests that +1q is not only a causative factor or poor outcomes in MM but may be targetable and/or predictive of response to novel therapies. This review will summarize our current understanding of the pathogenesis of +1q in plasma cell neoplasms, the impact of 1q copy number, identify potential genetic drivers of poor outcomes within this subset, and attempt to clarify its clinical significance and implications for the management of patients with multiple myeloma.Subject terms: Cancer genomics, Myeloma, Myeloma  相似文献   
4.
BACKGROUND AND PURPOSE:Head motion causes image degradation in brain MR imaging examinations, negatively impacting image quality, especially in pediatric populations. Here, we used a retrospective motion correction technique in children and assessed image quality improvement for 3D MR imaging acquisitions.MATERIALS AND METHODS:We prospectively acquired brain MR imaging at 3T using 3D sequences, T1-weighted MPRAGE, T2-weighted TSE, and FLAIR in 32 unsedated children, including 7 with epilepsy (age range, 2–18 years). We implemented a novel motion correction technique through a modification of k-space data acquisition: Distributed and Incoherent Sample Orders for Reconstruction Deblurring by using Encoding Redundancy (DISORDER). For each participant and technique, we obtained 3 reconstructions as acquired (Aq), after DISORDER motion correction (Di), and Di with additional outlier rejection (DiOut). We analyzed 288 images quantitatively, measuring 2 objective no-reference image quality metrics: gradient entropy (GE) and MPRAGE white matter (WM) homogeneity. As a qualitative metric, we presented blinded and randomized images to 2 expert neuroradiologists who scored them for clinical readability.RESULTS:Both image quality metrics improved after motion correction for all modalities, and improvement correlated with the amount of intrascan motion. Neuroradiologists also considered the motion corrected images as of higher quality (Wilcoxon z = −3.164 for MPRAGE; z = −2.066 for TSE; z = −2.645 for FLAIR; all P < .05).CONCLUSIONS:Retrospective image motion correction with DISORDER increased image quality both from an objective and qualitative perspective. In 75% of sessions, at least 1 sequence was improved by this approach, indicating the benefit of this technique in unsedated children for both clinical and research environments.

Head motion is a common cause of image degradation in brain MR imaging. Motion artifacts negatively impact MR image quality and therefore radiologists’ capacity to read the images, ultimately affecting patient clinical care.1 Motion artifacts are more common in noncompliant patients,2 but even in compliant adults, intrascan movement is reported in at least 10% of cases.3 For children who require high-resolution MR images, obtaining optimal image quality can be challenging, owing to the requirement to stay still over long durations needed for acquisition.4 Sedation can be an option, but it carries higher risks, costs, and preparation and recovery time.5In conditions such as intractable focal epilepsy, identification of an epileptogenic lesion is clinically important to guide surgical treatment. However, these lesions can be visually subtle, particularly in children in whom subtle cortical dysplasias are more common.6 Dedicated epilepsy MR imaging protocols use high-resolution 3D sequences to allow better cortical definition and free reformatting of orientation but involve acquisition times in the order of minutes, so data collection becomes more sensitive to motion.7For children in particular, multiple strategies are available for minimizing motion during MR examinations. Collaboration with play specialists using mock scanners and training or projecting a cartoon are good approaches to reduce anxiety.8,9 These tools are not always available in clinical radiology and, even with these strategies, motion can still be an issue.10 Different scanning approaches to correct for intrascan motion have been proposed. Broadly, prospective methods track head motion in real time and modify the acquisition directions accordingly.11 These approaches are applicable to a wide range of sequences but require optical systems with external tracking markers, sometimes uncomfortable or impractical, and extra setup can ultimately result in longer examinations. Furthermore, these approaches may also not be robust to continuous motion.11-13 Retrospective techniques have also been proposed, in some cases relying on imaging navigators that are not compatible with all standard sequences or contrasts.12Here, we use a more general retrospective motion correction technique: Distributed and Incoherent Sample Orders for Reconstruction Deblurring by using Encoding Redundancy (DISORDER). In this method, k-space samples are reordered to enable retrospective motion correction during image reconstruction.14 Our hypothesis is that DISORDER improves clinical MR imaging quality and readability. To assess its use for clinical sequences, we acquired a dedicated epilepsy MR imaging protocol in 32 children across a wide age range. We used both objective image quality metrics and expert neuroradiologist ratings to evaluate the outcome after motion correction.  相似文献   
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6.
Background: Cancer of unknown primary is the fourth most common cause of cancer death in the United Kingdom. National guidance in 2010 recommended the establishment of a dedicated unknown primary team to facilitate targeted investigation and symptom control. A service development project was undertaken to identify those affected by malignancy of unknown origin and institute a pathway for coordinating their care led by a palliative physician.

Method: In order to describe the patient population and illness trajectory and to assess the effect of the new pathway on the clinical outcomes we used a retrospective and prospective comparative case notes survey to identify the pre- and post-pathway population. This took place in secondary care. Inclusion criteria were patients with metastatic disease with no known primary; exclusion criteria were where the site of metastasis was so suggestive of a primary that it would be managed as per that disease process. 88 patients were included.Results: Mean age was 72.5 years. The mean survival time from presentation was 81.8 days. There was no difference pre or during pathway implementation in age, performance status or survival time. There was no reduction in the numbers referred for tumour directed therapy. There was a non-statistically significant reduction in the number who died in hospital during the pathway implementation.

Conclusions: This study suggests having a metastatic malignancy of unknown primary origin service led by a palliative physician does not reduce the number referred for tumour directed therapy. It also adds evidence of the poor prognosis and thus the need for early palliative care input.  相似文献   

7.
Gas-to-liquid (GTL) products are synthetic hydrocarbons produced from natural gas using a catalytic process known as the Fischer–Tropsch process. This process yields a synthetic crude oil that consists of saturated hydrocarbons which can subsequently be refined to a range of products analogous to those obtained from petroleum refining. However, in contrast to their petroleum-derived analogs, GTL products are essentially free of unsaturated or aromatic compounds and do not contain any sulfur-, oxygen-, or nitrogen-containing compounds. Under new chemical substance notification requirements, an extensive testing program covering the entire portfolio of GTL products has been undertaken to assess their hazardous properties to human health and environment. The results of these studies have been summarized in a two-part review. Part 1 provides an overview of the mammalian toxicity hazardous properties of the various GTL products. This second part of the review focuses on the aquatic, sediment, terrestrial, and avian toxicity studies which assess the ecotoxicological hazard profile of the GTL products. Many challenges were encountered during these tests relating to dosing, analysis and interpretation of results. These are discussed with the intent to share experiences to help inform and shape future regulatory mandates for testing of poorly soluble complex substances. As was the case with the mammalian toxicology review, there were a few cases where adverse effects were found, but overall the GTL products were found to exert minimal adverse ecotoxicological effects and these were less severe than effects observed with their conventional, petroleum-derived analogs.  相似文献   
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