Objectives
Technical assessment of SHINKEI pulse sequence and conventional 3DIRTSE for LS plexus MR neurography.
Methods
Twenty-one MR neurography examinations of the LS plexus were performed at 3 T, ...using 1.5-mm isotropic 3DIRTSE and SHINKEI sequences. Images were evaluated for motion and pulsation artefacts, nerve signal-to-noise ratio, contrast-to-noise ratio, nerve-to-fat ratio, muscle-to-fat ratio, fat suppression homogeneity and depiction of LS plexus branches. Paired Student
t
test was used to assess differences in nerve conspicuity (
p
< 0.05 was considered statistically significant). ICC correlation was obtained for intraobserver performance.
Results
Four examinations were excluded due to prior spine surgery. Bowel motion artefacts, pulsation artefacts, heterogeneous fat saturation and patient motion were seen in 16/17, 0/17, 17/17, 2/17 on 3DIRTSE and 0/17, 0/17, 0/17, 1/17 on SHINKEI. SHINKEI performed better (
p
< 0.01) for nerve signal-to-noise, contrast-to-noise, nerve-to-fat and muscle-to-fat ratios. 3DIRTSE and SHINKEI showed all LS plexus nerve roots, sciatic and femoral nerves. Smaller branches including obturator, lateral femoral cutaneous and iliohypogastric nerves were seen in 10/17, 5/17, 1/17 on 3DIRTSE and 17/17, 16/17, 7/17 on SHINKEI. Intraobserver reliability was excellent.
Conclusion
SHINKEI MRN demonstrates homogeneous and superior fat suppression with increased nerve signal- and contrast-to-noise ratios resulting in better conspicuity of smaller LS plexus branches.
Key Points
• SHINKEI provides homogeneous and superior fat suppression, shown by higher nerve and muscle-to-fat ratios.
• SHINKEI shows better nerve signal-to-noise and contrast-to-noise ratios than 3DIRTSE.
• SHINKEI enables nerve-selective images with increased conspicuity of smaller LS plexus branches.
• SHINKEI should be considered in routine MR neurography of the LS plexus.
Background
Pediatric interventional radiology has grown as an advanced subspecialty with increased demand, number and complexity of cases, and number of pediatric institutions offering a pediatric ...interventional radiology service. Despite the overall increase in the number of pediatric interventionalists over the past two decades, there is a heterogeneity in their academic backgrounds and a lack of uniform training pathways.
Objective
To analyze the demographics, academic backgrounds and scholarly activities of pediatric interventionalists across the United States (U.S.) and Canada.
Materials and methods
A list of all members of the Society for Pediatric Interventional Radiology was obtained and pediatric interventionalists at academic and private practice institutions in the U.S. and Canada were included. Publicly available online sources were used to gather demographic and educational information about each pediatric interventionalist, which included the online curriculum vitae, the
HealthGrades.com
and
Doximity.com
websites, and Elsevier’s Scopus database. Demographic and educational data including age, gender, educational background, additional degrees, academic rank, previous leadership positions, and metrics of scholarly activities were recorded. Fellowships in diagnostic pediatric radiology, adult interventional radiology and/or pediatric interventional radiology were recorded. Mann-Whitney
U
tests and Kruskal-Wallis tests were used to compare differences between groups.
Results
One hundred and twenty-five pediatric interventionalists were included, of whom 24 (19.2%) were female. The mean age was 48.6 years (standard deviation SD: 10.6, median: 45 years, range: 36–82 years). There was no statistical difference between median age for male versus female pediatric interventionalists (44.5 years vs. 45 years,
P
=0.89). A majority of pediatric interventionalists were American medical school graduates (96, 76.8%), while 29 (23.2%) were international medical graduates. Eighty-three percent (104) of the pediatric interventionalists completed diagnostic radiology residency training in the U.S., most commonly at the University of Cincinnati in Ohio (6.4%) and Washington University in St. Louis, MO (5.6%). Among fellowship training, pediatric interventionalists completed a pediatric radiology fellowship (61.6%), adult interventional radiology fellowship (40%) and/or a dedicated pediatric interventional radiology fellowship (57.6%). The mean±SD (median) publications, citations and Hirsch index (h-index) for pediatric interventionalists were 32±45 (12), 68±1,317 (120) and 9±10 (5), respectively. There was a statistically higher number of publications, citations and h-index with increasing academic rank at the assistant, associate and professor levels (
P
<0.001 for all groups). International medical graduate pediatric interventionalists had a higher, but not statistically significant, median publication count (26 vs. 11,
P
=0.0.25), citation count (236 vs. 93,
P
=0.36) and h-index (9.0 vs. 5,
P
=0.24) compared to pediatric interventional radiologists from American medical schools.
Conclusion
Pediatric interventionalists in North America are predominantly male, with about a quarter having graduated from international medical schools. Pediatric radiology fellowship, followed by pediatric interventional radiology fellowship, was the most frequently pursued training pathway.
Highlights • Uniform documentation of meniscal pathology is necessary for optimal multi-disciplinary communication and validation of patient outcomes. • ISAKOS arthroscopic meniscus tear ...classification system has been shown to provide sufficient interobserver reliability among the surgeons. • We discuss the MRI of meniscal tears based on ISAKOS classification on 2D and multiplanar 3D isotropic spin echo imaging techniques. • Meniscal pathologies are illustrated and correlated with relevant arthroscopic images. • ISAKOS classification will likely lead to better multi-disciplinary communication for the treatment of meniscal tears.
Cranial nerve disease outside the skull base is a common cause of facial and/or neck pain, which causes significant disability for patients and frustration for clinicians. Neuropathy in this region ...can be traumatic, idiopathic, or iatrogenic secondary to dental and surgical procedures. MR neurography is a modification of conventional MRI techniques dedicated to evaluation of peripheral nerves and is being increasingly used for imaging of peripheral neuropathies at various sites in the body. MR neurography facilitates assessment of different causes of craniofacial pain and cranial nerves and allows elegant depiction of a multitude of regional neuropathies. This article discusses the anatomy, pathologic conditions, and imaging findings of the commonly implicated but difficult to image infratentorial nerves, such as the peripheral trigeminal nerve and its branches, facial nerve, glossopharyngeal nerve, vagus nerve, hypoglossal nerve, and greater and lesser occipital nerves.
RSNA, 2018.
To determine the impact, if any, of the 2010 FDA safety communication on the rate of inferior vena cava filter (IVCF) placement over time.
The Nationwide Inpatient Sample was interrogated for the ...most recent years preceding and after the FDA safety communication-from 2005 to 2014. IVCF placements and associated diagnoses were identified using corresponding International Classification of Diseases, version nine codes. Trends in number of IVCF placement were evaluated in aggregate and by associated diagnoses, both of which were further stratified by hospital geographic cluster, hospital teaching status, and patient demographics. Generalized linear regression models were used to determine statistical significance of trends over time.
IVCF placements steadily increased between 2005 and 2010 (100,434 in 2005 versus 129,614 in 2010, growth rate 5.81%). Aggregate IVCF placements subsequently declined between 2010 and 2014 (96,005 in 2014, decline rate -6.48%). IVCF placements peaked in 2010, the year of the FDA advisory. The proportion of filter placements for therapeutic indication of venous thromboembolism increased significantly during the study period (69.8% in 2005 versus 80.4% in 2014, P < .001). Neither trend varied significantly by patient demographics or hospital characteristics.
IVCF placements have declined significantly since 2010, when the FDA advisory was released. The proportion of IVCFs placed in patients with venous thromboembolism, as opposed to prophylactic indications, is increasing.
Highlights • The Spring ligament complex is an important stabilizer of medial arch of foot. • Of all SLC components, the integrity of Supero-Medial band is the most important. • Associated ...pathologies with SLC instability include PTT injury, pes planovalgus and sinus tarsi syndrome. • Conservative and operative management are viable depending on pes planovalgus progression.
Purpose
To evaluate the feasibility of whole‐body magnetic resonance neurography (WBMRN) in polyneuropathy for technical feasibility, distribution of nerve abnormalities, and differentiation.
...Materials and Methods
Twenty WBMRN examinations were performed on a 3T scanner over 2 years. Patient demographics including history of hereditary and acquired neuropathy were recorded. The images were evaluated by two independent readers with nerve imaging experience for quality. The nerve signal and size alterations were measured in the brachial plexus, lumbosacral plexus, and femoral and sciatic nerves; diffusion tensor imaging parameters (fractional anisotropy FA and apparent diffusion coefficient ADC) were determined in plexuses, and tractography was performed. Nonparametric Wilcoxon rank sum test, receiver operating characteristic (ROC) analysis, and intraclass correlation coefficients (ICCs) were obtained.
Results
Excellent image quality was obtained for the majority of lumbosacral (LS) plexus (18/20) and 50% of brachial plexus (10/20) regions. Qualitatively among cases, the nerve hyperintensity and/or thickening involved the brachial plexus (11/11), LS plexus (7/11), and both plexuses (7/11), with most nerve thickenings observed in Charcot‐Marie‐Tooth disease type 1. The nerve signal intensity alterations were significantly different for both brachial (P < 0.05) and LS (P < 0.05) plexuses in cases versus controls. The femoral and sciatic nerve size alterations were different (P < 0.05), while signal intensity differences were not significant (P = 0.1–0.97). Transverse dimensions of C8 (4 mm), L5 (6.2 mm) and S1 (5.1 mm) nerve roots, and sciatic nerves (10.2 mm) were the most accurate diagnostic performance measures in distinguishing cases from controls.
Conclusion
WBMRN is feasible for use in the clinical practice for the identification and potential characterization of polyneuropathy. J. Magn. Reson. Imaging 2016;44:1513–1521.
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