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Use of fast-sequence spine MRI in pediatric patients

Jordan I. Gewirtz, Alex Skidmore, Matthew D. Smyth, David D. Limbrick Jr., Manu Goyal, Joshua S. Shimony, Robert C. McKinstry, Mari L. Groves, and Jennifer M. Strahle

T raditional spine MRI protocols require the patient to remain still during the examination, frequently resulting in the need for sedation in young children. The immediate and long-term risk of anesthesia in the pediatric population is controversial. Studies suggesting the possibility of negative neurocognitive outcomes with prenatal or pediatric exposure to general anesthesia have led the US FDA to issue updated warnings and require label changes on general anesthesia and sedation medications regarding the dangers of repeated use in pregnant women and children

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Comparison of MRI techniques for detecting microadenomas in Cushing's disease

Yuval Grober, Hagit Grober, Max Wintermark, John A. Jane Jr., and Edward H. Oldfield

T he ACTH-secreting pituitary adenomas that cause Cushing's disease are often so small that they are difficult to detect with pituitary MRI. Surgical remission rates for Cushing's disease are in the range of 80%–90% when a tumor is detected on MRI, but decrease to 50%–70% when MRI fails to detect a lesion. 19 , 23 In patients with Cushing's syndrome but a negative pituitary MRI, inferior petrosal sinus sampling (IPSS) is done in many centers to confirm Cushing's disease as the source of excess adrenocorticotropic hormone (ACTH) production. 14 , 22 Although

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Prospective observational study of acute postlumbar laminectomy MRI

Clinical article

Scott D. Wait, M. Yashar S. Kalani, Andrew S. Little, Giac D. Consiglieri, Jeffrey S. Ross, Matthew R. Kucia, Volker K. H. Sonntag, and Nicholas Theodore

lumbar spine on MRI in this immediate postoperative period is not well described and may be useful in interpreting MR images in patients who awake with unanticipated findings. Methods Institutional review board approval was obtained prior to undertaking this study. Twenty-four nonconsecutive patients were enrolled in the study. All patients underwent single or multilevel laminectomies with or without a discectomy. No patient who underwent anterior, lateral, or “minimally invasive” approaches was included. To avoid the degradation of images due to artifact, no

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Upright MRI after decompression of spinal stenosis and concurrent spondylolisthesis

Michael Kern, Matthias Setzer, Lutz Weise, Ali Mroe, Holger Frey, Katharina Frey, Volker Seifert, and Stephan Duetzmann

could develop micro-instability 7 and be on the way to clinically significant instability but not yet have obvious symptoms of instability. 18 , 19 Previous analysis of radiographic data showed a slip progression rate in 5 years of only 8% in flexion/extension radiographs. 5 We hypothesized that the actual rate was much higher and that radiographs represent a rather crude method to detect this. Thus we conducted a retrospective analysis of cases involving patients treated from 2010 through 2013 and conducted upright MRI studies in flexion and extension to identify

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Analysis of the utility of early MRI/MRA in 400 patients with spontaneous intracerebral hemorrhage

Nohra Chalouhi, Nikolaos Mouchtouris, Fadi Al Saiegh, Somnath Das, Ahmad Sweid, Adam E. Flanders, Robert M. Starke, Michael P. Baldassari, Stavropoula Tjoumakaris, Michael Reid Gooch, Syed Omar Shah, David Hasan, Nabeel Herial, Robin D’Ambrosio, Robert Rosenwasser, and Pascal Jabbour

S pontaneous , nontraumatic intracerebral hemorrhage (ICH) accounts for 10%–20% of all strokes, with high rates of morbidity and mortality. 7 The most common etiologies are hypertension and cerebral amyloid angiopathy, but there are multiple other causes of ICH, including vascular, neoplastic, or infectious lesions that affect the immediate management of these patients. 3 , 6 , 12 Although CT has high sensitivity for identifying acute ICH and is considered the gold standard, it does not allow for diagnosis of underlying structural lesions. MRI and MRA studies

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Portable MRI to assess optic chiasm decompression after endoscopic endonasal resection of sellar and suprasellar lesions

Christopher S. Hong, Layton A. Lamsam, Vineetha Yadlapalli, Nethra Parasuram, Mercy Mazurek, Isha Chavva, Dheeraj Lalwani, Julia Zabinska, Steven J. Schiff, R. Peter Manes, Eugenia M. Vining, Ryan A. Rimmer, W. Taylor Kimberly, Kevin N. Sheth, and Sacit Bulent Omay

B edside low-field portable MRI (pMRI) is a recent technological advancement with potential for broad applications ranging from rural hospitals with limited resources to emergency departments, neurointensive care units, and even operating rooms in the tertiary care setting. Compared with conventional MRI scanners, pMRI is more cost-effective to purchase and maintain, does not require specialized technicians to operate, and can be rapidly deployed in a variety of settings as a point-of-care diagnostic tool. 1 Portable MRI has also been proposed as a means

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Deep brain stimulator implantation in a diagnostic MRI suite: infection history over a 10-year period

Alastair J. Martin, Paul S. Larson, Nathan Ziman, Nadja Levesque, Monica Volz, Jill L. Ostrem, and Philip A. Starr

I ntraoperative MRI has been used for a range of neurosurgical procedures such as tumor resection monitoring, biopsy, and laser ablation. 6 Over the past 10 years, we have pioneered the use of interventional (i)MRI techniques to implant deep brain stimulation (DBS) electrodes. 10 , 11 , 16 Precise electrode placement within a selected brain region is necessary to achieve efficacy, which is traditionally done with frame-based or “frameless” neuronavigation-guided stereotaxy supported by invasive physiological testing including microelectrode recording

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Fast-sequence MRI studies for surveillance imaging in pediatric hydrocephalus

Clinical article

Daxa M. Patel, R. Shane Tubbs, Gigi Pate, James M. Johnston Jr., and Jeffrey P. Blount

this patient population. 14 Brenner et al. performed a retrospective review of children treated at St. Louis Children's Hospital and estimated lifetime cancer mortality risks attributable to the radiation exposure from a CT scan in a 1-year-old child as 0.18% (abdominal) and 0.07% (head). They also observed that radiation risk is highest in the youngest children. 3 To eliminate the risk of radiation exposure, MRI is increasingly used. Traditional MR images require longer acquisition time and sedation, which can result in an increased risk from anesthetic

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Ferumoxytol-enhanced MRI for surveillance of pediatric cerebral arteriovenous malformations

Yuhao Huang, Timothy G. Singer, Michael Iv, Bryan Lanzman, Siddharth Nair, James A. Stadler III, Jia Wang, Michael S. B. Edwards, Gerald A. Grant, Samuel H. Cheshier, and Kristen W. Yeom

. Gadolinium-enhanced MRI/MRA is frequently used in conjunction with DSA for the surveillance of cerebral AVMs, especially after the first surveillance DSA study is negative for residual AVM. However, the sensitivity and specificity for evaluating cerebral AVMs using MRI/MRA have ranged from 76.7% to 84.9% and 88.9% to 95.2%, respectively. 11 Due to its imperfect sensitivity, gadolinium-enhanced MRI is not recommended as the sole modality for AVM follow-up. 15 A recent study has shown that ferumoxytol (Feraheme, AMI-7228, AMAG Pharmaceuticals, Inc.), a blood pool agent

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Differentiation of idiopathic spinal cord herniation from dorsal arachnoid webs on MRI and CT myelography

Randall Schultz Jr., Andrew Steven, Aaron Wessell, Nancy Fischbein, Charles A. Sansur, Dheeraj Gandhi, David Ibrahimi, and Prashant Raghavan

similar as well. In a review of 27 patients with SCH by Tekkök, 15 a correct preoperative diagnosis was made in only 9, with SCH being confused most often with dorsal arachnoid cysts or masses. On MRI and myelography, both entities present as focal anterior displacements of the midthoracic cord with widening of the posterior subarachnoid space. The arachnoid web and the dural defect through which the cord herniates are difficult to directly visualize on imaging. Indeed, some cases of SCH were mistakenly attributed to ventral displacement of the cord by dorsally located