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Rationale and Objectives Fluid-attenuated inversion recovery (FLAIR) imaging can detect elevated protein levels in fluid that may be difficult or impossible to detect with T1- or T2-weighted imaging. The purpose of this study is to evaluate the frequency and asses the diagnostic utility of abnormal FLAIR signal in various types of inner ear and internal auditory canal (IAC) pathology. Materials and Methods A retrospective review of medical records and magnetic resonance images from 187 consecutive patients who underwent imaging of the temporal bones for possible inner ear or IAC pathology over a 1-year period were reviewed for abnormal increased FLAIR signal, increased intrinsic T1 signal, abnormal enhancement after gadolinium administration, and the presence of a mass lesion within the cerebellopontine angle, IAC, or inner ear. Reviewers were blinded to clinical diagnosis. Results Twenty-five of 32 (78%) patients with schwannomas restricted to the IAC and cerebellopontine angle demonstrated associated increased FLAIR signal within the ipsilateral inner ear structures. The sensitivity, specificity, positive predictive value, and negative predictive value of inner ear FLAIR hyperintensity for a schwannoma were 80%, 95%, 78%, and 95%, respectively. Inner ear FLAIR hyperintensity was also seen in cases of intracochlear hemorrhage, labyrinthitis, and labyrinthitis ossificans, but these conditions did not occur with sufficient frequency in our study population to determine statistical significance. Conclusion Identification of inner ear FLAIR hyperintensity can alert the radiologist to scrutinize pre- and post-gadolinium T1-weighted images and T2-weighted images for subtle IAC and inner ear abnormalities. Although enhancement after the administration of gadolinium contrast media is the gold standard for detection of schwannoma, inner ear FLAIR hyperintensity may be a helpful diagnostic adjunct for vestibular schwannoma. This may be particularly helpful when gadolinium was not administered and the T2-weighted images are equivocal, especially when dedicated thin-section imaging of the IACs and temporal bones was not performed.

Dural arteriovenous fistulae (dAVF) provide a diagnostic challenge and must be part of a broad differential in pursuit of a difficult diagnosis or unusual presentation. This case report demonstrates an initially misguided diagnosis of bilateral thalamic neoplasm and demonstrates the importance of continued pursuit until the correct diagnosis is obtained. Moreover, to our knowledge, this is the first reported case of a dAVF simulating a bilateral thalamic neoplasm. We present a patient with a provisional diagnosis of bilateral thalamic neoplasm based on clinical history and an advanced imaging workup including MR spectroscopy. Subsequent biopsy suggested venous congestion, hypoxia, and edema without neoplasia. Routine post-operative CT the following day revealed suggestion of dAVF due to the presence of residual contrast from prior unrelated abdominal CT. Cerebral angiography eventually revealed a Cognard grade IIb dAVF. Trans-arterial Onyx embolization resulted in a dramatic clinical and radiographic improvement. This case highlights an unusual presentation and challenging diagnosis of a dAVF and the importance of pursuing the correct diagnosis.

No current therapy for relapsing-remitting multiple sclerosis (MS) results in significant reversal of disability.To determine the association of nonmyeloablative hematopoietic stem cell transplantation with neurological disability and other clinical outcomes in patients with MS.Case series of patients with relapsing-remitting MS (n = 123) or secondary-progressive MS (n = 28) (mean age, 36 years; range, 18-60 years; 85 women) treated at a single US institution between 2003 and 2014 and followed up for 5 years. Final follow-up was completed in June 2014.Treatment with cyclophosphamide and alemtuzumab (22 patients) or cyclophosphamide and thymoglobulin (129 patients) followed by infusion of unmanipulated peripheral blood stem cells.Primary end point was reversal or progression of disability measured by change in the Expanded Disability Status Scale (EDSS) score of 1.0 or greater (score range, 0-10). Secondary outcomes included changes in the Neurologic Rating Scale (NRS) score of 10 or greater (score range, 0-100), Multiple Sclerosis Functional Composite (MSFC) score, quality-of-life Short Form 36 questionnaire scores, and T2 lesion volume on brain magnetic resonance imaging scan.Outcome analysis was available for 145 patients with a median follow-up of 2 years and a mean of 2.5 years. Scores from the EDSS improved significantly from a pretransplant median of 4.0 to 3.0 (interquartile range [IQR], 1.5 to 4.0; n = 82) at 2 years and to 2.5 (IQR, 1.9 to 4.5; n = 36) at 4 years (P .001 at each assessment). There was significant improvement in disability (decrease in EDSS score of ≥1.0) in 41 patients (50%; 95% CI, 39% to 61%) at 2 years and in 23 patients (64%; 95% CI, 46% to 79%) at 4 years. Four-year relapse-free survival was 80% and progression-free survival was 87%. The NRS scores improved significantly from a pretransplant median of 74 to 88.0 (IQR, 77.3 to 93.0; n = 78) at 2 years and to 87.5 (IQR, 75.0 to 93.8; n = 34) at 4 years (P .001 at each assessment). The median MSFC scores were 0.38 (IQR, -0.01 to 0.64) at 2 years (P .001) and 0.45 (0.04 to 0.60) at 4 years (P = .02). Total quality-of-life scores improved from a mean of 46 (95% CI, 43 to 49) pretransplant to 64 (95% CI, 61 to 68) at a median follow-up of 2 years posttransplant (n = 132) (P .001). There was a decrease in T2 lesion volume from a pretransplant median of 8.57 cm3 (IQR, 2.78 to 22.08 cm3) to 5.74 cm3 (IQR, 1.88 to 14.45 cm3) (P .001) at the last posttransplant assessment (mean follow-up, 27 months; n = 128).Among patients with relapsing-remitting MS, nonmyeloablative hematopoietic stem cell transplantation was associated with improvement in neurological disability and other clinical outcomes. These preliminary findings from this uncontrolled study require confirmation in randomized trials.

A novel transosseous approach for percutaneous access of the lumbar subarachnoid space is described in a patient with advanced ankylosing spondylitis (AS) and instrumented spinal fusion who presented for myelography. Use of a coaxial threaded bone biopsy system to provide transosseous access to the thecal sac, imaging findings, and outcome are discussed. This technique provided access to an otherwise inaccessible subarachnoid space and is an alternative approach in the setting of advanced AS or posterior spinal fusion.

Capecitabine is used to treat advanced breast and gastrointestinal malignancies. A single case of encephalopathy and three cases of peripheral neuropathy are the only neurotoxicities reported. The authors report five additional cases of capecitabine-induced multifocal leukoencephalopathy.

Bevacizumab has been reported to cause diffusion restriction in the tumor bed of patients with malignant gliomas. This study evaluated prolonged diffusion restriction, in the corpus callosum (CC), of patients with malignant brain tumors treated with bevacizumab. We retrospectively reviewed our database of patients treated with bevacizumab for malignant brain tumors looking for those with restricted diffusion in the CC. CC ADC ratio measurements were obtained prior to and following treatment. Correlation was made with biopsy (n = 3) and MR perfusion (n = 7) and PET (n = 4). The temporal evolution of these changes relative to therapy was examined with mixed effects regression analysis. Nine patients (eight malignant gliomas, one malignant meningioma) out of 146 patients were found to have developed areas of diffusion restriction in the CC. These areas tended to enlarge and coalesce over serial MRIs and persisted for up to 22 months. Hypoperfusion was demonstrated in MR perfusion in 7/7. PET was hypometabolic in all 4. Biopsy of the CC showed no tumor in 3/3. ADC ratio measurements indicated a significant overall effect of time (F(16,60) = 11.2; p < 0.0001), consistent with persistent diffusion restriction over the measured time periods. Bevacizumab causes prolonged diffusion restriction in the CC. The negative MR perfusion, FDG PET and histopathology suggest this is a toxicity of bevacizumab and not active tumor. Awareness of these changes can assist in patient care.

✓The authors report a unique case of subarachnoid hemorrhage caused by a traumatic pseudoaneurysm of the ophthalmic artery, which was successfully treated with coil embolization. Clinical and imaging features, as well as the relevant literature, are described.

We present a method of quantifying cerebral blood volume using dynamic susceptibility contrast. Our approach combines T(2)-weighted echo planar imaging (EPI) pulse sequences and reference scans that determine the parenchymal T(1) changes resulting from an injection of a gadolinium chelate. This combined T(2)- and T(1)-weighted approach (the "bookend" technique) has been shown to be effective in the quantification of gradient-echo (GRE) (T(2)*-weighted) perfusion images but has not been applied to spin-echo EPI (SE-EPI) (T(2)-weighted) images. The physics related to blood volume measurement based on T(2)- and T(2)*-weighted EPI sequences is known to be different, and there is a question as to whether the bookend approach is effective with SE-EPI. We have compared the quantitative SE-EPI with GRE-EPI in a series of patients with central nervous system (CNS) tumors. We found that quantitative cerebral blood volume (qCBV) values for SE-EPI and GRE-EPI are in agreement with each other and with historical reference values. A subjective evaluation of image quality showed that image quality in the SE-EPI scans was high and exhibited high interreader agreement. We conclude that measuring qCBV using the bookend technique with SE-EPI images is possible and may be a viable alternative to GRE-EPI in the evaluation of CNS tumors.

BACKGROUND AND PURPOSE: Contrast-enhanced MR angiography (CE MRA) is a proven diagnostic tool in evaluation of the carotid arteries; however, few studies have addressed its accuracy in the vertebrobasilar system. The purpose of this study was to assess the sensitivity and specificity of CE MRA compared with digital subtraction angiography (DSA) for detection of vertebrobasilar disease. METHODS: Forty patients with suspected atherosclerotic disease of the carotid and vertebrobasilar circulations underwent CE MRA on a 1.5T MR imaging scanner by use of a coronal 3D gradient-echo pulse sequence after intravenous injection of gadolinium diethylene triamine penta-acetic acid. All patients had correlative DSA within a 1-month period. CE MRA images were randomized and then independently assessed by 2 observers who were blinded to the DSA results. DSA examinations were analyzed in a similar manner. Each observer was asked to report the presence or absence of clinically significant stenosis (>50%), occlusion, fistula, aneurysm, and dissection. The MRA findings were then correlated with DSA. RESULTS: The sensitivity and specificity of MRA for detection of disease in the entire carotid and vertebrobasilar systems were 90% and 97%, respectively; for the carotid system alone, the sensitivity and specificity were 94% and 97%, respectively; and for the vertebrobasilar system they were 88% and 98% respectively. The overall interobserver reliability was 98% (κ = 0.92). CONCLUSION: CE MRA is accurate at detecting disease not only in the carotid vessels, but also in the vertebrobasilar circulation, and has the potential to provide a comprehensive and noninvasive evaluation of the head and neck arteries in a single study.

Objective. To determine whether anteroposterior (AP) and lateral views of the knee are equivalent to four views in acute fracture detection. Design. Three musculoskeletal radiologists retrospectively interpreted the plain film knee examinations of each patient, establishing ground truth for the presence or absence of a fracture. Cases were presented to four masked senior radiology residents twice – once as a two-view study and again as a four-view study – with 4 weeks separating the two reading sessions to minimize recall bias. Sensitivity, specificity, and diagnostic performance were calculated. Patients. Ninety-two patients presenting to the emergency department with acute knee trauma were evaluated with at least a four-view plain film examination. Results and conclusions. Mean sensitivity for fracture detection using four views (85%) was significantly higher than that using two views (79%). Mean specificity and receiver operating characteristic curve areas were not significantly different using two or four views. Four views are more sensitive than AP and lateral views alone in detection of acute knee fracture.

Objective: This study investigates MRI changes that may predict which brain tumor patients are at increased risk for seizures. Background The 2000 AAN practice parameter states that prophylactic anticonvulsants should not be used in patients with newly diagnosed brain tumors. Many physicians still administer prophylactic anticonvulsants. Design/Methods: A retrospective chart review compared primary brain tumor patients presenting with seizures to those who did not. A neuro-radiologist blinded to seizure status read initial MRIs. Imaging factors such as lesion type, presence of necrosis, mass effect (ME), tumor enhancement (TE) and cortical involvement (CI) were measured. Degree of TE was rated 0-4+. Cortical involvement was rated of 0-3. Results: Of the 40 patients included in the study, 19 presented with seizures. All patients were diagnosed with high-grade gliomas (GBM = 37, AG =2), except 1 patient (had oligodendroglioma). Lesion type (seizure/non-seizure): multifocal (26.3%/19.1%), single (47.7%/71.4%), single with satellites (21.1%/9.5%). Necrosis (seizure/non-seizure): 63.2%/95.2%. ME (seizure/non-seizure): no ME (42.1%/9.52%), mild ME (36.8%/23.6%), mild-moderate ME (5.3%/28.6%), moderate (15.8%/33.3%). TE (seizure/non-seizure): 0(25%/0%), 1+(10.5%/4.8%), 2+(10.5%/4.8%), 3+(26.3%/19.0%), 4+(36.8%/71.4%). CI (seizure/non-seizure): 0(0%/19.0%), 1(5.3%/4.8%), 2(0%/14.3%), 3(94.7%/61.9%), 4(0%/0%). Conclusions: Patients with seizures were more likely to have multifocal or single lesions with satellites, no necrosis, no or mild ME, less TE and more CI than patients without seizures. Seizures likely occur from cortical involvement unless necrosis is present and there is loss of neurons. These imaging findings need to be validated in larger patient population and suggest that there may be imaging factors that can guide physicians on which primary brain tumor patients to treat with anti-convulsants. Disclosure: Dr. Coffino has nothing to disclose. Dr. Carroll has nothing to disclose. Dr. Grimm has nothing to disclose. Dr. Raizer has received personal compensation for activities with Genentech, Merck, and Enzon as a speaker and advisory board member. Dr. Raizer has received research support from Genentech Inc., Novartis, Lilly, Myriad, Arno, and Med-Immune. Dr. Futterer has nothing to disclose.