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991.
《Journal of the American College of Radiology》2016,13(11):1324-1336
There has been a rapid increase in the number of shoulder arthroplasties, including partial or complete humeral head resurfacing, hemiarthroplasty, total shoulder arthroplasty, and reverse total shoulder arthroplasty, performed in the United States over the past two decades. Imaging can play an important role in diagnosing the complications that can occur in the setting of these shoulder arthroplasties. This review is divided into two parts. The first part provides a general discussion of various imaging modalities, comprising radiography, CT, MRI, ultrasound, and nuclear medicine, and their role in providing useful, treatment-guiding information. The second part focuses on the most appropriate imaging algorithms for shoulder arthroplasty complications such as aseptic loosening, infection, fracture, rotator cuff tendon tear, and nerve injury.The evidence-based ACR Appropriateness Criteria guidelines offered in this report were reached via an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (the RAND/UCLA Appropriateness Method and the Grading of Recommendations Assessment, Development, and Evaluation) for rating the appropriateness of imaging and treatment procedures for specific clinical scenarios. Further analysis and review of the guidelines were performed by a multidisciplinary expert panel. In those instances in which there was insufficient or equivocal data for recommending the appropriate imaging algorithm, expert opinion may have supplemented the available evidence. 相似文献
992.
4D flow MRI can detect subtle right ventricular dysfunction in primary left ventricular disease
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993.
Reproducibility and interobserver variability of systolic blood flow velocity and 3D wall shear stress derived from 4D flow MRI in the healthy aorta
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994.
Feasibility of a reduced field‐of‐view diffusion‐weighted (rFOV) sequence in assessment of myometrial invasion in patients with clinical FIGO stage I endometrial cancer
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995.
Assessment of renal function using intravoxel incoherent motion diffusion‐weighted imaging and dynamic contrast‐enhanced MRI
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996.
Repeatability and sensitivity of
measurements in patients with head and neck squamous cell carcinoma at 3T
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Rafal Panek PhD Liam Welsh PhD Alex Dunlop PhD Kee H. Wong MSc Angela M. Riddell MD Dow‐Mu Koh MD Maria A. Schmidt PhD Simon Doran PhD Dualta Mcquaid PhD Georgina Hopkinson PgDip Cheryl Richardson DCR Christopher M. Nutting PhD Shreerang A. Bhide PhD Kevin J. Harrington PhD Simon P. Robinson PhD Kate L. Newbold MD Martin O. Leach PhD 《Journal of magnetic resonance imaging : JMRI》2016,44(1):72-80
997.
Evaluation of interobserver variability and diagnostic performance of developed MRI‐based radiological scoring system for invasive placenta previa
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998.
Open‐MRI measures of cam intrusion for hips in an anterior impingement position relate to acetabular contact force
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Lawrence L. Buchan Honglin Zhang Sujith Konan Ingrid Heaslip Charles R. Ratzlaff David R. Wilson 《Journal of orthopaedic research》2016,34(2):205-216
Open MRI in functional positions has potential to directly and non‐invasively assess cam femoroacetabular impingement (FAI). Our objective was to investigate whether open MRI can depict intrusion of the cam deformity into the intra‐articular joint space, and whether intrusion is associated with elevated acetabular contact force. Cadaver hips (9 cam; 3 controls) were positioned in an anterior impingement posture and imaged using open MRI with multi‐planar reformatting. The β‐angle (describing clearance between the femoral neck and acetabulum) was measured around the entire circumference of the femoral neck. We defined a binary “MRI cam‐intrusion sign” (positive if β < 0°). We then instrumented each hip with a piezoresistive sensor and conducted six repeated positioning trials, measuring acetabular contact force (F). We defined a binary “contact‐force sign” (positive if F > 20N). Cam hips were more likely than controls to have both a positive MRI cam‐intrusion sign (p = 0.0182, Fisher's exact test) and positive contact‐force sign (p = 0.0083), which represents direct experimental evidence for cam intrusion. There was also a relationship between the MRI cam‐intrusion sign and contact‐force sign (p = 0.033), representing a link between imaging and mechanics. Our findings indicate that open MRI has significant potential for in vivo investigation of the cam FAI mechanism. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:205–216, 2016. 相似文献
999.
Differences in the vascular tree of the femoral trochlear growth cartilage at osteochondrosis‐susceptible sites in foals revealed by SWI 3T MRI
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Gabrielle Martel Sabrina Kiss Guillaume Gilbert Nicolas Anne‐Archard Hélène Richard Thomas Moser Sheila Laverty 《Journal of orthopaedic research》2016,34(9):1539-1546
Focal ischemic chondronecrosis of epiphyseal growth cartilage (EGC) during endochondral ossification is believed to be a key early event on the pathway to osteochondrosis (OC) in both animals and humans. The lateral ridge of the equine trochlea is a site where severe osteochondritis dissecans lesions frequently arise and is a model for the study of naturally occurring disease. Non‐invasive imaging to investigate EGC vascularity may help elucidate why focal ischemia occurs. 3T MRI susceptibility‐weighted imaging (SWI) of femoral trochlea of OC predisposed (n = 10) and control (n = 6) day‐old foals, with minimal joint loading after birth, was performed. SWI and 3D images revealed the EGC vascular architecture without a contrast agent, and matched histologic observations. No vascular lesions were identified. There was no difference in the vascular density and architecture between control and OC specimens, but a striking difference in vascular pattern was seen at the OC‐predilected site in the lateral ridge of the trochlea in all specimens, when compared to the medial ridge of the trochlea, where OC lesions are rarely observed. This site was less ossified with more perichondrial vessels not yet bridging with the subchondral bone. Furthermore, the mean vascular density of all specimens was significantly higher at this site. We speculate that joint morphology and focal internal trauma on this site with a unique vascular architecture may trigger ischemic events at this site. SWI permitted visualization of EGC in young foals with a clinical 3T MRI and paves the way for non‐destructive longitudinal studies to improve understanding of OC in all species. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1539–1546, 2016. 相似文献
1000.
目的探讨高分辨MRI(HR-MRI)双重造影结合弥散加权成像(DWI)判断直肠癌T分期的方法和效果。方法回顾性分析赤峰市医院2014年3月至2016年5月收治的84例原发性直肠癌患者的临床资料。通过HR-MRI双重造影结合DWI综合分析判定直肠癌的大小、浸润程度、与邻近器官的关系,做出术前T分期诊断,并与术后病理相对照,判断影像学方法对T分期诊断的准确性。结果本组84例原发性直肠癌患者均可被HR-MRI双重造影结合DMI检出,T分期诊断准确率为78.6%(66/84)。结论 HR-MRI双重造影结合DWI对直肠癌术前T分期具有较高的诊断价值。 相似文献