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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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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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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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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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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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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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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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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

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Hirotaka Hasegawa, Akitoshi Inoue, Ahmed Helal, Kosuke Kashiwabara, and Fredric B. Meyer

including internal septations, thicker wall with nodularity, multilobulated shape, and multicystic appearance may be possible. Signal intensity (SI) on MRI is variable depending on the cyst components, although usually it is similar but slightly hyperintense to CSF on T1-weighted and FLAIR images. 7 , 8 The etiology of PC remains to be elucidated, but there are several theories, such as an enlargement of the embryonic pineal cavity, ischemic degeneration of glial plaques, and necrotic/hemorrhagic degeneration of pineal parenchyma. 2 , 7 – 11 Female prevalence may also

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Aaron E. Bond, Robert F. Dallapiazza, M. Beatriz Lopes, and W. Jeffrey Elias

S tereotactic surgery is commonly used to treat chronic neurological disorders such as Parkinson's disease, tremor, epilepsy, and psychiatric diseases. Lesioning, stimulation, and local delivery of drugs 9 , 22 all rely on the ability to treat specific brain regions that are often small, deep, and indistinct on conventional MRI. Validation of their placement typically requires clinical testing or electrophysiological mapping with microelectrode recordings (MERs), or both of these. 8 , 18 , 29 , 32–35 Image-guided techniques have been developed to