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Since the relatively recent regulatory approval for clinical use in both Europe and North America, 7-Tesla (T) MRI has been adopted for clinical practice at our institution. Based on this experience, this article reviews the unique features of 7-T MRI neuroimaging and addresses the challenges of establishing a 7-T MRI clinical practice. The underlying fundamental physics principals of high-field strength MRI are briefly reviewed. Scanner installation, safety considerations, and artifact mitigation techniques are discussed. Seven-tesla MRI case examples of neurologic diseases including epilepsy, vascular abnormalities, and tumor imaging are presented to illustrate specific applications of 7-T MRI. The advantages of 7-T MRI in conjunction with advanced neuroimaging techniques such as functional MRI are presented. Seven-tesla MRI produces more detailed information and, in some cases, results in specific diagnoses where previous 3-T studies were insufficient. Still, persistent technical issues for 7-T scanning present ongoing challenges for radiologists.

Traumatic brain injuries (TBI) are commonly associated with motor vehicle accidents. Neuroimaging plays a crucial role in the initial management of TBIs. We present a case of a TBI related to a motor vehicle accident in an 18-year-old woman. Initial brain imaging revealed significant traumatic injuries and an enhancing mass, without restricted diffusion, in the thalamus favored to be a thalamic glioma. Subsequent imaging revealed resolution of enhancement of the thalamic lesion and reduction in size. On review of the original imaging, it was determined that the thalamic lesion was related to a tear and partial thrombosis of a large thalamic vein resulting in infarction and hemorrhage.

Background Carotid-cavernous fistulas (CCFs) are commonly misdiagnosed on computed tomography angiography (CTA). Purpose This study sought to identify the most sensitive and specific imaging features of CCFs on CTA. Material and Methods A retrospective review identified 18 consecutive patients suspected of having a CCF on CTA and subsequently underwent digital subtraction angiography (DSA). Two blinded reviewers assessed multiple findings on CTA: cavernous sinus asymmetry/enlargement; arterial-phase contrast in the cavernous sinus; proptosis; pre- or post-septal orbital edema; and dilated regional vasculature. Each was graded as positive, possible, and negative; “possible” was counted as positive. A third blinded reviewer served as a tiebreaker. Results Of 18 patients, nine were true-positive and nine were false-positive. Superior ophthalmic vein early enhancement and dilatation had 100.0% sensitivity (95% confidence interval [CI] 40.0–100.0) and 77.8% specificity (95% CI 44.4–100.0); arterial-phase contrast in the cavernous sinus had 88.9% sensitivity (95% CI 44.4–100.0) and 66.7% specificity (95% CI 18.5–90.1); peri-orbital edema had 88.9% sensitivity (95% CI 35.5–100.0) and 77.8% specificity (95% CI 22.2–100.0). The most specific markers of CCF were superior petrosal sinus and inferior ophthalmic vein dilatation/enhancement (100.0%, 95% CI 88.8–100.0 and 88.9%, 95% CI 44.4–100.0, respectively); the specificity of asymmetric cavernous enlargement was 44.4% (95% CI 11.1–77.7). Conclusions Among patients in whom a CCF is suspected on CTA, superior ophthalmic vein dilatation/enhancement and arterial-phase contrast within the cavernous sinus are the most sensitive findings. Asymmetric cavernous sinus enlargement has poor specificity and may result in false-positive diagnoses of CCFs. False positive cases were less likely to have an optimally timed contrast bolus.

Background There are numerous barriers to identifying patients with silent brain infarcts (SBIs) and white matter disease (WMD) in routine clinical care. A natural language processing (NLP) algorithm may identify patients from neuroimaging reports, but it is unclear if these reports contain reliable information on these findings. Methods Four radiology residents reviewed 1000 neuroimaging reports (RI) of patients age > 50 years without clinical histories of stroke, TIA, or dementia for the presence, acuity, and location of SBIs, and the presence and severity of WMD. Four neuroradiologists directly reviewed a subsample of 182 images (DR). An NLP algorithm was developed to identify findings in reports. We assessed interrater reliability for DR and RI, and agreement between these two and with NLP. Results For DR, interrater reliability was moderate for the presence of SBIs (k = 0.58, 95 % CI 0.46–0.69) and WMD (k = 0.49, 95 % CI 0.35–0.63), and moderate to substantial for characteristics of SBI and WMD. Agreement between DR and RI was substantial for the presence of SBIs and WMD, and fair to substantial for characteristics of SBIs and WMD. Agreement between NLP and DR was substantial for the presence of SBIs (k = 0.64, 95 % CI 0.53–0.76) and moderate (k = 0.52, 95 % CI 0.39–0.65) for the presence of WMD. Conclusions Neuroimaging reports in routine care capture the presence of SBIs and WMD. An NLP can identify these findings (comparable to direct imaging review) and can likely be used for cohort identification.

Since the relatively recent regulatory approval for clinical use in both Europe and North America, 7-Tesla (T) MRI has been adopted for clinical practice at our institution. Based on this experience, this article reviews the unique features of 7-T MRI neuroimaging and addresses the challenges of establishing a 7-T MRI clinical practice. The underlying fundamental physics principals of high-field strength MRI are briefly reviewed. Scanner installation, safety considerations, and artifact mitigation techniques are discussed. Seven-tesla MRI case examples of neurologic diseases including epilepsy, vascular abnormalities, and tumor imaging are presented to illustrate specific applications of 7-T MRI. The advantages of 7-T MRI in conjunction with advanced neuroimaging techniques such as functional MRI are presented. Seven-tesla MRI produces more detailed information and, in some cases, results in specific diagnoses where previous 3-T studies were insufficient. Still, persistent technical issues for 7-T scanning present ongoing challenges for radiologists.

Background Given the absence of consensus diagnostic criteria for giant cell arteritis, clinicians may encounter difficulty with identification of new-onset headache in patients older than age 50 years presenting with visual changes and elevated inflammatory markers, particularly if temporal artery biopsies are performed and negative. Case presentation We present a case of a 57-year-old white man with headache, diplopia, and jaw paresthesia initially diagnosed and managed as steroid-refractory biopsy-negative giant cell arteritis. Further investigation disclosed evidence of soft tissue infiltration into Meckel’s (trigeminal) cave bilaterally. Positron emission tomography suggested the presence of a lymphoproliferative disorder. Histology confirmed the diagnosis of diffuse large B cell lymphoma. Conclusions Metastatic involvement in Meckel’s cave in diffuse large B cell lymphoma is extremely rare and presents a diagnostic challenge. Patients with suspicion of giant cell arteritis should undergo advanced imaging, particularly those with negative biopsy, atypical features, or lack of response to standard therapy, in order to assess for the presence of large-vessel vasculitis or other mimicking pathologies.

BACKGROUND AND PURPOSE: There is a general assumption in the cerebrovascular literature that there is an association between carotid artery tortuosity and connective tissues disease; however, this has not been firmly established. The purpose of this study was to determine the prevalence of carotid artery tortuosity in patients with connective tissue diseases relative to matched controls. MATERIALS AND METHODS: Patients with previous CTA or MRA and a diagnosis of connective tissue diseases were identified and compared with a cohort of age-matched controls. Radiologists blinded to the diagnosis reviewed the images and evaluated the presence of carotid artery tortuosity (including loops, kinks, or coils). Continuous variables were compared using the Student t test, and categoric variables with χ(2) tests. RESULTS: One hundred forty-three patients with connective tissue disease and 143 controls were included in this study. Specific diagnoses included Marfan (n = 33), nonvascular Ehlers-Danlos (n = 36), Ehlers-Danlos vascular-type (n = 32), neurofibromatosis type 1 (n = 26), and Loeys-Dietz (n = 16) syndromes. The presence of carotid tortuosity was 44% in connective tissue disease and 16% in controls (P < .001). Of tortuosity manifestations, coils were most prevalent (23% versus 3%; P < .001). Among the various connective tissue diseases, the rates of any carotid tortuosity were 88% for Marfan syndrome, 63% for Loeys-Dietz syndrome, 42% for neurofibromatosis type 1, and 19% for both vascular- and nonvascular-type Ehlers-Danlos syndrome. The positive predictive value of the combination of aortic aneurysm and carotid tortuosity being associated with connective tissue disease was 95.4%. The specificity was 98.6%. CONCLUSIONS: Carotid artery tortuosity is highly associated with connective tissue diseases, particularly Marfan syndrome, Loeys-Dietz syndrome, and neurofibromatosis type 1. Such findings are relevant in risk assessment for vascular complications in connective tissue disease, endovascular treatment planning, and in understanding the pathomechanisms of vascular tortuosity in general.

Background Identification of the central sulcus can require inspection of subtle differences or require certain pulse sequences. This study identifies the central sulcus by signal intensity on Double Inversion Recovery (DIR) images in multiple anatomic locations and imaging planes. Methods 49 patients (98 hemispheres) were retrospectively reviewed by three neuroradiologists and one radiology resident. The central sulcus was compared to the surrounding sulci for differences in signal intensity at axial hand knob, axial operculum, and lateral convexity sagittal images (294 locations) on DIR images. The use of the 'disappearing central sulcus sign' where the window level is increased at constant width and black/white inversion were also assessed. Results In 49 patients (22 female, 27 male; median age 36 years), the central sulcus cortex signal intensity was lower than adjacent sulci with a frequency of 90/98 (91.8%) at the axial hand knob level, 68/98 (69.4%) at the axial operculum level, and 76/98 (77.5%) at the sagittal level. With black and white inversion, the frequencies were of 96/98 (98%), 92/98 (94%), and 87/98 (89%). The central sulcus was the first to disappear at all three levels with high degrees of inter-reader agreement (86%-99%). Traditional anatomic landmarks were absent or conflicting in seven hemispheres (5 patients). The central sulcus was identified by DIR signal intensity in all seven hemispheres. Conclusions The central sulcus can be identified by differences in signal intensity of the peri-rolandic cortex on DIR. Use of black/white inversion and the disappearing central sulcus sign may further facilitate identification.

Posterior reversible encephalopathy syndrome refers to a neuroradiologic disorder in which seizure activity (multiple seizures are more common than single events) is commonly the initial presenting symptom. We describe a case of posterior reversible encephalopathy syndrome in a previously healthy parturient who presented to the labor and delivery suite with generalized tonic-clonic seizures. Prompt recognition and treatment of this potentially catastrophic disease may avert injury to the patient and neonate.

The clinical significance of cerebral microbleeds (CMB) in patients hospitalized with atrial fibrillation (AF) and cerebral ischemia is unclear. We aimed to determine the prevalence of CMB in this population and determine the future risk of intracerebral hemorrhage (ICH) and cerebral infarction (CI). The medical records and brain imaging of patients hospitalized with cerebral ischemia due to AF between 2008 and 2011 were reviewed. Followup was obtained through medical record review, mailed survey, and acquisition of death certificates. Prevalence was calculated from those patients with a hemosiderin-sensitive MRI sequence. Recurrent CI and ICH were calculated using Kaplan-Meier curves censored at 3 years. Among 426 patients hospitalized with cerebral ischemia due to AF, 134 had an MRI with hemosiderin-sensitive sequences. The prevalence of CMB was 27.6%. At 3 years, 90.6% of CMB-negative patients were overall stroke free (ICH and CI) compared to 78.6% CMB-positive patients (p = 0.0591). Only one patient in the CMB-positive group had an ICH distant to the CMB. There was a nonsignificant trend toward higher recurrent CI, recurrent overall stroke rate, and mortality in patients with 5 or more CMB compared to 0-4 CMB. The rate of prospective CI in patients with prior cerebral ischemia due to AF is higher than the rate of ICH in patients with CMB. Further study is warranted to assess larger numbers of patients to determine appropriate antithrombotic use in this high-risk population.

PURPOSE: To compare the accuracy of a fluid-attenuated inversion-recovery (FLAIR) sequence with that of a conventional double spin-echo (SE) sequence in the identification of increased signal intensity of the hippocampus in mesial temporal sclerosis (MTS). MATERIALS AND METHODS: Three blinded reviewers independently graded the FLAIR and SE images in 36 patients with intractable complex partial seizures. Reproducibility was tested. At histopathologic examination, the criterion standard, 32 patients had MTS. RESULTS: The accuracy of FLAIR images was 97% versus 91% for SE images (P

OBJECTIVE AND IMPORTANCE A case of acutely symptomatic epidural hematoma caused by metastatic hepatocellular carcinoma (HCC) to the cranium is reported. This is a rare case of metastatic HCC without known primary presenting as an epidural hematoma. CLINICAL PRESENTATION The patient presented with an acute onset of headache, aphasia, and right hemiparesis 2 weeks after he experienced minor trauma to the cranium. An emergency computed tomographic scan of the head revealed the presence of a left parietal epidural hematoma. INTERVENTION An emergency evacuation of the epidural hematoma was performed, and metastatic HCC was diagnosed. CONCLUSION The patient's neurological deficits were reversed with surgical intervention, and he is now undergoing palliative chemotherapy. This was the first clinical manifestation of HCC in this patient. This case reaffirms the neurosurgeon's role in the complex, multidisciplinary care of patients with craniospinal metastasis.

Feingold syndrome is a rare autosomal dominant condition that is characterized by variable expressivity of microcephaly, limb malformations, esophageal atresia, and a host of other malformations. This syndrome results from mutations in the MYCN proto-oncogene. Few examples of cross-sectional imaging of the brain in these patients are found in the literature. We present a patient who was found to have areas of cerebral and cerebellar white matter hyperintensity with T2 weighted magnetic resonance (MR) imaging. To the best of our knowledge, this finding has not been previously described. While the significance and pathologic basis of this finding are unknown, its recognition is important since it has potential to be confused with imaging findings in other conditions. Moreover, it is likely to be observed in the future due to increased use of MR imaging.

To determine the accuracy of elliptic centric contrast material-enhanced magnetic resonance (MR) angiography by using conventional angiography as the reference standard.Fifty patients were examined prospectively with contrast-enhanced MR angiography and conventional angiography. The two examinations were performed within 1 week of each other. Two patients underwent conventional angiography of only one carotid artery, which yielded 98 arteries for comparison.With conventional angiography as the reference standard and by using a 70% threshold for internal carotid arterial diameter stenosis, maximum intensity projection (MIP) images had a sensitivity of 93.3%, specificity of 85.1%, and accuracy of 87.6%, whereas reformatted transverse source images had a sensitivity of 83.3%, specificity of 97.0%, and accuracy of 92.8%. Interobserver variability for conventional angiograms was 0.97, for MIP images was 0.91, and for source images was 0.90. The contrast-enhanced MR angiographic technique had a sensitivity of 88.9% and specificity of 58.1% for the presence of irregularity and/or ulceration. All 50 examinations were triggered appropriately so that minimal or no venous signal intensity was depicted.Contrast-enhanced elliptic centric three-dimensional MR angiography offers high-spatial-resolution, venous-suppressed images of the carotid arteries that appear to be adequate to replace conventional angiography in most patients examined prior to carotid endarterectomy.

The optimization of contrast is considered for the fluid-attenuated inversion recovery (FLAIR) MRI pulse sequence, specifically the contrast of multiple sclerosis (MS) to white matter (WM). A performance bound is identified at 1.5 Tesla as that provided using an inversion time (TI) of 2900 ms. It is shown that TR/TI times exceeding 11000/2600 ms provide about 90% of the MS-WM contrast possible theoretically. The commonly reported TR/TI combination of 6000/2000 provides only about 60%. For TR times exceeding 8000 ms, an echo time (TE) of 140 ms is at or near optimum. Use of TR/TI times less than 9000/2400 lacks efficiency in multisection imaging. Predicted relative contrast performance of TR/TI 11000/2600 versus 6000/2000 was evaluated in seven patients with known MS lesions, and measurements closely matched theoretical predictions. It is strongly recommended that for near optimum contrast and high multisection efficiency, FLAIR should be performed with TR/TI times exceeding 10000/2500 ms.