We have identified details of both PTA/PTAV. The incidence of PTA was similar to previous studies, and the co-existence of cerebral aneurysm was also similar when compared to patients in the general population without PTA or PTAV.

MR angiography is useful as the primary diagnostic tool for evaluating suspected intracranial steno-occlusive disease.

To determine the characteristics of sudden deafness associated with slow blood flow (SBF) within the vertebrobasilar arteries, we evaluated 57 patients with sudden deafness using magnetic resonance imaging (MRI). We detected SBF in 12 (21%) patients, predominantly men over 50 years of age. A second MRI performed in 5 patients 2 months after the onset of symptoms showed recovery of blood flow. All 12 patients complained of vertigo. Audiological and neurotologic tests suggested that hearing loss mainly involved the inner ear. Our findings suggest that unless central lesions are detected, headache, hypoesthesia of the external ear canal, and electronystagmographic abnormalities are signs of SBF. Because sudden deafness may recur in patients who have SBF, they should be monitored and treated to prevent recurrence.

To assess tissue changes responsible for enhancement of the meninges adjacent to meningiomas on magnetic resonance (MR) images, the authors correlated the MR imaging characteristics of meningeal lesions seen before and after administration of gadolinium diethylenetriamine-pentaacetic acid (DTPA) with the appearance of these lesions on contrast material-enhanced computed tomographic (CT) images and with histopathologic findings in four patients. Histopathologic examination of meninges showed increased loose connective tissue, hypervascularity, and dilated vessels. There was neoplastic infiltration of the dura mater in two patients but it was restricted to the immediate junction of neoplasm and dura mater, with maximum peripheral extension within 1 mm of the tumor margin. In both patients the meninges were enhanced far beyond the neoplastic infiltration. The other two patients showed no infiltration of dura mater. These findings suggest that pathologic enhancement of meninges adjacent to meningioma after administration of Gd-DTPA mainly represents reactive changes to the neoplasm and does not necessarily indicate neoplastic involvement.

SUMMARY:IVL is characterized by a propensity for intravascular tumor cell proliferation. Premortem diagnosis of IVL is difficult because of its nonspecific clinical, laboratory, and imaging manifestations. This study examined cerebral MR imaging patterns of IVL and their changes with and without chemotherapy. Nine of 11 patients studied presented with abnormal findings. We define 5 patterns of abnormal MR imaging findings: 1) infarctlike lesions, 2) nonspecific white matter lesions, 3) meningeal enhancement, 4) masslike lesions, and 5) hyperintense lesions in the pons on T2WI. Seven patients presented with only 1 pattern, while 2 patients presented with multiple patterns. Lesions in 7 treated patients responded to chemotherapy. Pathologic specimens revealed intravascular tumor cell infiltration with associated infarctions, necrosis, congestion, demyelination, vasculitis, and tumor cell extravasation. We conclude that MR imaging patterns can be possible manifestations of intravasculardominant infiltration by tumor cells with associated occlusion or inflammation, depending on the level of affected vessels.ABBREVIATIONS: IVL ϭ intravascular large B-cell lymphoma; PRES ϭ posterior reversible encephalopathy syndrome; R-CHOP ϭ rituximab with cyclophosphamide, vincristine, doxorubicin, and prednisolone

MRI using T(2)*-WI is a sensitive, specific, and accurate method to evaluate EP. T(2)*-WI is highly accurate for detecting and diagnosing EP because of its sensitivity to fresh hematoma.

Purpose:To assess the efficacy of 1 H MR spectroscopy (MRS) to evaluate early responses to neoadjuvant chemotherapy in breast cancer patients, as compared to that of the standardized uptake value (SUV) in 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET). Materials and Methods:This retrospective study included seven patients with breast cancer who had both single-voxel 1 H MRS and PET/computed tomography (CT) acquired before, during, and after neoadjuvant chemotherapy. Results:The averages of the Choline (Cho) integral value and peak SUV before chemotherapy were 2.5 (range, 1.2-5.3) and 7.5 (range, 1.9 -19), respectively. Three cases became negative for both Cho and peak SUV after two cycles of chemotherapy, and one patient became negative before surgery. In the remaining three patients, the curves of both values paralleled the time course of chemotherapy treatment. The difference between Cho and peak SUV before, during, and after chemotherapy was r ϭ 0.65 (P ϭ 0.12), r ϭ 0.80 (P ϭ 0.03), and r ϭ 0.99 (P Ͻ 0.001), respectively. The reduction rate (RR) of both values after chemotherapy was also correlated (r ϭ 0.84, P ϭ 0.02). Conclusion:A change in the Cho integral value is well correlated with that of peak SUV in the time course of neoadjuvant chemotherapy; thus, breast 1 H MRS is thought to be an alternative to sequential 18 F-FDG PET.

BACKGROUND: Intravascular large B-cell lymphoma (IVL) is characterized by lymphoma cell proliferation in the lumina of small vessels in various organs. A high incidence of neurologic symptoms associated with the central nervous system has been reported, but peripheral nerve involvement (neurolymphomatosis [NL]) rarely has been described. METHODS: The medical records from patients who were diagnosed with IVL over the past 4 years were reviewed. A diagnosis of NL was made based on the combination of neurologic symptoms and their correspondence with imaging studies, such as magnetic resonance imaging (MRI), 18 F-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography/computed tomography (PET/CT), and/or the histologic confirmation of lymphoma cells within the peripheral nerves, nerve root/plexuses, or cranial nerves. RESULTS: Four patients with NL were identified among 11 patients who had IVL. All cases of NL occurred as relapsed disease during or shortly after the completion of chemotherapy. Although MRI studies of the brains and whole spines revealed nerve infiltration by gadolinium enhancement in 2 patients, the technology was not sensitive enough to detect such infiltration in the remaining 2 patients. In contrast, FDG-PET/CT studies successfully revealed cranial or peripheral nerve lesions in all 4 patients and was useful for evaluating therapeutic response. Patients received treatment with high-dose methotrexate with or without other systemic chemotherapy, which achieved varied success. Further studies will be needed to determine the optimal treatment. CONCLUSIONS: Considering the rarity of IVL and NL, the current observations suggested that IVL may have a predilection not only for the vessels but also for both the central and peripheral nervous systems. Cancer 2011;117:4512-