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Objective: The recent FDA approval of the first 7T MRI scanner for clinical diagnostic use in October 2017 will likely increase the utilization of 7T for epilepsy presurgical evaluation. This study aims at accessing the radiological and clinical value of 7T in patients with pharmacoresistant focal epilepsy and 3T-visible lesions.Methods: Patients with pharmacoresistant focal epilepsy were included if they had a lesion on pre-operative standard-of-care 3T MRI and also a 7T research MRI. An epilepsy protocol was used for the acquisition of the 7T MRI. Prospective visual analysis of 7T MRI was performed by an experienced board-certified neuroradiologist and communicated to the patient management team. The clinical significance of the additional 7T findings was assessed by intracranial EEG (ICEEG) ictal onset, surgical resection, post-operative seizure outcome and histopathology. A subset of lesions were demarked with arrows for subsequent, retrospective comparison between 3T and 7T by 7 neuroradiologists using a set of quantitative scales: lesion presence, conspicuity, boundary, gray-white tissue contrast, artifacts, and the most helpful sequence for diagnosis. Conger's kappa for multiple raters was performed for chance-adjusted agreement statistics.Results: A total of 47 patients were included, with the main pathology types of focal cortical dysplasia (FCD), hippocampal sclerosis, periventricular nodular heterotopia (PVNH), tumor and polymicrogyria (PMG). 7T detected additional smaller lesions in 19% (9/47) of patients, who had extensive abnormalities such as PMG and PVNH; however, these additional findings were not necessarily epileptogenic. 3T−7T comparison by the neuroradiologist team showed that lesion conspicuity and lesion boundary were significantly better at 7T (p < 0.001), particularly for FCD, PVNH and PMG. Chance-adjusted agreement was within the fair range for lesion presence, conspicuity and boundary. Gray-white contrast was significantly improved at 7T (p < 0.001). Significantly more artifacts were encountered at 7T (p < 0.001).Significance: For patients with 3T-visible lesions, 7T MRI may better elucidate the extent of multifocal abnormalities such as PVNH and PMG, providing potential targets to improve ICEEG implantation. Patients with FCD, PVNH and PMG would likely benefit the most from 7T due to improved lesion conspicuity and boundary. Pathologies in the antero–inferior temporal regions likely benefit less due to artifacts.

Our case describes rhabdomyolysis of the paraspinal muscles occurring after acute type A aortic dissection. Lumbar arteries that supply the paraspinal muscles may become compromised because of either hypoperfusion or occlusion from aortic cross-clamping, or ligation of the vessels within the false lumen of the dissection, or from atheroembolic phenomena. The resultant ischemia causes edema and necrosis of the paraspinal muscles, subsequently increasing the pressure within the paraspinal compartment. Treatment includes fluid administration, urine alkalinization, and monitoring for signs of acute renal failure.

Background T1-weighted magnetic resonance imaging (MRI) remains the standard pituitary imaging sequence. However, up to 50% of pituitary adenomas are missed with standard imaging in Cushing's disease (CD) patients. Utility of other imaging sequences needs be explored. Objective To compare a T2-gradient echo sequence, constructive interference in steady state (CISS), with a contrast-enhanced (CE) T1-weighted sequence, volume-interpolated breath-hold examination (VIBE), in the detection of pituitary adenomas in CD patients. Design Retrospective analysis of CD patients who underwent endoscopic transsphenoidal pituitary adenomectomy at our institution. Patients and Measurement Twelve patients were included in the study. Two neuroradiologists, who were blinded to the patients' clinical and surgical findings, independently reviewed the CE-VIBE and CISS images. Localization of pituitary adenoma from imaging was compared with intraoperative localization. Results The averaged sensitivity of detecting pituitary adenoma in CD patients was not significantly different between CE-VIBE sequence (63%) and CISS sequence (54%). The positive predictive value was 75% (Observer A) and 100% (Observer B) with CE-VIBE sequence, and 64% (Observer A) and 100% (Observer B) with CISS sequence. In two patients, pituitary adenoma was easily localized with CISS sequence but hard to detect with CE-VIBE sequence. In two other patients, the adenoma was much better delineated on CE-VIBE sequence. Conclusion In our series, the addition of CISS sequence to T1-weighted MRI imaging protocols improved the detection of pituitary adenomas in CD patients. CISS sequence may be a useful adjunct to T1-weighted pituitary MRI protocols and an appropriate alternative for patients with gadolinium contraindications.

BACKGROUND AND PURPOSE:Deriving accurate language lateralization from fMRI studies in the clinical context can be difficult, with 10%-20% incorrect conclusions. Most interpretations are qualitative, performed by neuroimaging experts. Quantitative lateralization has been widely described but with little implementation in the clinical setting and is disadvantaged by the use of arbitrary threshold techniques. We investigated the application and utility of a nonthreshold CLI, in a clinical setting, as applied by a group of practicing neuroradiologists.