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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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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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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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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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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

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Abdelilah el Barzouhi, Carmen L. A. M. Vleggeert-Lankamp, Geert J. Lycklama à Nijeholt, Bas F. Van der Kallen, Wilbert B. van den Hout, Bart W. Koes and Wilco C. Peul

M agnetic resonance imaging is widely used in diagnosis and treatment planning for patients with intervertebral disc herniations. 4 It is considered the imaging procedure of choice for patients with suspected lumbar disc herniation 18 , 28 and is indicated in patients with severe symptoms who do not respond to 6–8 weeks of conservative care. 17 Qualitative MRI findings, such as the presence of disc extrusion or severe nerve root compression, have indeed been reported to be strongly associated with sciatica. 3 In addition, the size and shape of disc

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Brandon G. Chew, Christopher M. Spearman, Matthew R. Quigley and James E. Wilberger

of a CT scan that fails to account for such deficits. Increasingly, MRI has been used in the evaluation of the stabilized TBI patient in the acute setting. This imaging modality provides superior visualization of the brainstem and allows for delineation of areas of edema, ischemia, hemorrhage, and infarction. While such injuries are often ominous signs, outcomes can range from complete recovery to severe disability or death. Although MRI may help clarify the anatomical extent of neurological injury and account for abnormal findings on neurological examination

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Stephen T. Magill, Marcel Brus-Ramer, Philip R. Weinstein, Cynthia T. Chin and Line Jacques

, electrodiagnostic studies, and therapeutic trials. Until recently, MRI for TOS evaluation was unable to accurately predict intraoperative findings; new imaging sequences were needed to improve the diagnostic accuracy of MRI. Singh et al. tried to correlate MRI results with intraoperative findings but were successful in identifying surgically proven points of compression by MRI in less than 50% of patients, demonstrating the need for improved MRI. 18 MR neurography (MRN) has been available as a specialized imaging study since 1993, when Filler et al. reported methods for