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41.
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   
42.
Background/ObjectiveOccurrence of post-dural puncture headache (PDPH) after diagnostic lumbar puncture (LP) for idiopathic intracranial hypertension (IIH) may seem very unlikely in clinical practice. Nevertheless, it has been suggested by several studies, mainly in sub-group analyses. We aimed to evaluate the prevalence of PDPH in an IIH population and determine any eventual predictive factors of PDPH occurrence.MethodsWe conducted a retrospective multiple-center observational study. All newly diagnosed IIH patients who met the International Classification of Headache Disorders (ICHD-3) or the Dandy modified criteria were included from three different French hospitals. They all underwent LP following the same process with the same type of needle. We recorded PDPH occurring within five days after LP, as defined by ICHD-3 criteria.ResultsSeventy-four IIH patients were recruited, of whom 23 (31%) presented with PDPH. Neither classical risk factors for PDPH such as body mass index, age or gender, nor cerebrospinal fluid opening pressure, or specific IIH features were associated with occurrence of PDPH.ConclusionPDPH can occur after LP in IIH patients. Clinicians should be aware of this possible event during the IIH diagnosis assessment and should not automatically reconsider IIH diagnosis. PDPH prevention using an atraumatic needle and dedicated PDPH treatment seem relevant in IIH patients.  相似文献   
43.
AimsOrgan preservation, an important goal in the treatment of head and neck squamous cell carcinoma (HNSCC), may include induction chemotherapy and cisplatin with radiation therapy (CRT). To our knowledge, no reports have directly compared the impact of induction chemotherapy with that of CRT on health-related quality of life (HRQOL).Materials and methodsIn a phase II trial, we assessed the HRQOL of patients treated with induction chemotherapy followed by CRT. Eligible patients had stage III–IV HNSCC. HRQOL questionnaires were administered at baseline, the end of induction (EOI), the end of CRT (EOCRT) and after CRT. Functional Assessment of Cancer Therapy (FACT version 4) assessed HRQOL. We carried out a comparison of changes in HRQOL from baseline to EOI and from EOI to EOCRT. This trial is registered with ClinicalTrials.gov (NCT01566435).ResultsThirty patients were enrolled in the study. Most HRQOL questionnaires were completed (88%). The mean total FACT scores did not differ from baseline to EOI (general: 83.8 versus 79.1, P = 0.08; head and neck: 109.7 versus 105.8, P = 0.33; Total Outcome Index: 69.7 versus 62.3, P = 0.03; respectively, using P ≤ 0.01 to adjust for multiple simultaneous tests of differences). However, total FACT scores significantly worsened from EOI to EOCRT (79.1 versus 62.3, P = 0.01; 105.8 versus 74.2, P < 0.01; 62.3 versus 34.2, P = 0.01; respectively). Within domains, the head and neck cancer subscale score did not differ from baseline to EOI (median 28.5 versus 27.0, P = 0.69), but significantly worsened from EOI to EOCRT (27.0 versus 9.5, P < 0.01). Swallowing, oral pain and voice quality improved from baseline to EOI, but worsened from EOI to EOCRT. Physical and functional scores worsened from baseline to EOI and from EOI to EOCRT. The emotional well-being score improved from baseline to EOI but worsened from EOI to EOCRT.ConclusionsOverall, HRQOL did not significantly change from baseline to EOI but dramatically worsened from EOI to EOCRT.  相似文献   
44.

Purpose

To investigate the preoperative use of combination metformin and statin versus monotherapy on biochemical recurrence (BCR) after radical prostatectomy (RP) in diabetic men.

Patients and Methods

Data of 843 diabetic men who underwent RP were stratified on the basis of preoperative use of no drug or of metformin, statin, or both. Multivariable Cox models were used to test the association between treatment and BCR. In a secondary analysis, models were stratified by race and body mass index (BMI) and further adjusted for glycated hemoglobin (HbA1c).

Results

A total of 259 men (31%) received statin therapy, 94 (11%) metformin, 307 (36%) metformin + statin, and 183 (22%) neither. Five-year BCR-free survival rates were 75% in metformin only versus 75% in metformin + statin versus 60% in statin versus 68% in no drug groups (log-rank, P = .003). On multivariable analysis, preoperative statin use was associated with increased BCR risk versus men receiving neither drug (hazard ratio [HR] = 1.84; 95% confidence interval [CI], 1.28-2.64). Metformin alone (HR 0.88; 95% CI, 0.53-1.47) and metformin + statin (HR 0.88; 95% CI, 0.58-1.33) were unrelated to BCR risks. In secondary analysis, the association between statin use and higher BCR risk was similar regardless of race, but was stronger among men with BMI ≥ 30 kg/m2 (HR 3.12; 95% CI, 1.70-5.72). These results were largely unchanged after adjusting for HbA1c.

Conclusion

Among diabetic men undergoing RP, preoperative statin use was associated with worse BCR risk, especially among men with a high BMI, but these associations may be mitigated by concomitant use of metformin. If validated in future findings, research is needed to understand the basis for these associations.  相似文献   
45.

Background

Private hospital rooms have a number of potential advantages compared to shared rooms, including reduced noise and increased control over the hospital environment. However, the association of room type with patient experience metrics in total joint arthroplasty (TJA) patients is currently unclear.

Methods

For private versus shared rooms, we compared our institutional Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) scores in patients who underwent primary TJA over a 2-year period. Regression model odds ratios (ORs) were adjusted for surgeon, date of surgery, and length of stay.

Results

Patients in private rooms were more likely to report a top-box score for overall hospital rating (85.6% vs 79.4%, OR = 1.53, P = .011), hospital recommendation (89.3% vs 83.0%, OR = 1.78, P = .002), call button help (76.0% vs 68.7%, OR = 1.40, P = .028), and quietness (70.4% vs 59.0%, OR = 1.78, P < .001). There were no significant differences on surgeon metrics including listening (P = .225), explanations (P = .066), or treatment with courtesy and respect (P = .396).

Conclusion

For patients undergoing TJA, private hospital rooms were associated with superior performance on patient experience metrics. This association appears specific for global and hospital-related metrics, with little impact on surgeon evaluations. With the utilization of HCAHPS data in value-based initiatives, placement of TJA patients in private rooms may lead to increased reimbursement and higher hospital rankings.

Level of Evidence

Level III, retrospective cohort.  相似文献   
46.

Background

Comprehensive Care for Joint Replacement (CJR) is a Medicare initiative to test the impact of holding a hospital accountable for services provided during an episode of care for a lower extremity joint arthroplasty on costs and quality. This study examines whether hospital participation in CJR is associated with having programs focused on improving posthospitalization care or reducing costs using a survey of orthopedic surgeons.

Methods

Seventy-three (of 104) orthopedic surgeon members of the Hip Society, a national professional organization of hip surgeons, completed the survey.

Results

Surgeons practicing in CJR hospitals were more likely to report that their hospital had implemented programs focused on improving posthospitalization care or reducing costs. Surgeons in CJR hospitals were significantly more likely to report that the hospital had a narrow network of skilled nursing facilities to enhance care and limit length of stay in skilled nursing facilities (83% vs 47%, P < .01). Surgeons in CJR hospitals were also more likely to report the hospital provides incentives or some type of gainsharing. There were no statistically significant differences in implementation of having programs to reduce costs or improve care during hospitalization.

Conclusion

Participation in CJR is associated with higher utilization of hospital practices aimed at improving postdischarge care and higher utilization of linking surgeon compensation to cost and quality.  相似文献   
47.

Background

Anterior knee pain (AKP) remains a complex issue affecting patient satisfaction after total knee arthroplasty. Several radiographic parameters have been shown to be causative factors with various designs. The aim of this study is to evaluate the known radiographic parameters of AKP and clinical outcomes (ie, AKP) in the setting of a modern prosthesis with an anatomic patella button.

Methods

Between July 2012 and December 2013, 90 total knee arthroplasties received 3 skyline views taken at 30°, 45°, and 60°. A patient-administered questionnaire was administered at 2-year follow-up to assess the incidence of AKP, painless noise, and satisfaction. Radiographs were analyzed for patellofemoral overstuffing, patellar tilt, and patellar displacement, and evaluated the patella resection angle.

Results

On the patient-administered questionnaire, 10 (11.1%) patients reported AKP of a mild-to-moderate nature. Thirty-one had the best view at 30 Merchant views, 24 had best views at 45, and 35 had best views at 60. We found that patellar resection angle correlated with AKP (odds ratio 1.21, P = .044) and painless noise (odds ratio 1.22, P = .034). Patellar displacement and patellofemoral stuffing did not correlate with AKP or painless noise. No radiographic measurements correlated with changes in Knee Society Score pain or function scores or range of motion.

Conclusion

We found that a patellar resection angle correlated with the incidence of AKP and painless noise at 2-year follow-up. We failed to find any correlation with patellofemoral overstuffing, patellar displacement, or patellar tilt with clinical outcomes. We recommend the use of 3 Merchant views to fully evaluate the patellofemoral joint.  相似文献   
48.

Background

Liver transplantation from donors after either controlled or uncontrolled cardiac death (DCD) is associated with considerable rates of primary nonfunction (PNF) and ischemic cholangiopathy (IC). Normothermic regional perfusion (NRP) could significantly reduce such rates.

Methods

Retrospective study to analyze short-term (mortality, PNF, vascular complications) and long-term (IC, survival) complications in 11 liver transplants from controlled DCDs using NRP with extracorporeal membrane oxygenation (ECMO) (group 1). They were compared with 51 patients transplanted with grafts from donors after brain death (DBD) (group 2). Mean recipient age, sex, and Model for End-stage Liver Disease (MELD) score were not significantly different.

Results

In group 1, mean functional warm ischemia time was 15.8 (range, 7–40) minutes and 94.1 (range, 20–150) minutes on NRP. The ischemic damage was minimal, as shown by the slight alanine aminotransferase (ALT) and aspartate aminotransferase (AST) rises in the donor serum after 1 hour on NRP and similar rises 24 hours after transplantation in both groups. No patient had IC or acute renal failure. No significant difference was found between the groups for vascular or biliary complications. One group 1 patient had PNF (9.1%), resulting in death. Overall retransplantation and in-hospital death rates were 8.1% and 4.8%, respectively, with no significant difference between groups. Estimated mean survival was 24.6 (95% confidence interval [CI], 20.2–29.1) months in group 1 and 32.3 (95% CI, 30.4–34.2) months in group 2 (not a statistically significant difference).

Conclusion

In our experience, liver transplants from controlled DCDs using NRP with ECMO is associated with a low risk of PNF and IC, with short- and long-term results comparable to those in DBD transplants.  相似文献   
49.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
50.
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