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Renal cell carcinoma (RCC) is one of the most common human cancers. We previously reported that claspin is a key regulator in the progression of gastric cancer, and it likely plays an important role in cancer stem cells of gastric cancer. However, the significance of claspin in RCC has not been examined. First, we analyzed the expression and distribution of claspin in 95 RCC cases by immunohistochemistry. In the nonneoplastic kidney, the staining of claspin was either weak or absent, whereas RCC tissue showed nuclear staining. In total, claspin expression was detected in 45 (47%) of 95 RCC cases. The claspin staining appeared relatively stronger in high nuclear grade RCC than in low nuclear grade RCC. Claspin‐positive RCC cases were associated with higher T grade, tumor stage, nuclear grade, vein invasion, and poorer prognosis. CLSPN siRNA treatment decreased RCC cell proliferation. The levels of phosphorylated Erk and Akt were lower in CLSPN siRNA‐transfected RCC cells than in control cells. In addition, claspin was coexpressed with CD44, epidermal growth factor receptor, p53, and programmed death ligand‐1. These results suggest that claspin plays an important role in tumor progression in RCC and might be a prognostic marker and novel therapeutic target molecule., The present study is the first detailed analysis of claspin expression in renal cell carcinoma (RCC) including its clinicopathological significance and biological function. Our investigation showed that claspin plays an important role in tumor progression in RCC and might be a prognostic marker and novel therapeutic target molecule.

Objective: Esophageal cancer is one of the deadliest cancers in the world, and the main subtype is esophageal squamous cell carcinoma (ESCC), which comprises 90% of cases. Expression of tryptophan 2,3-dioxygenase (TDO2), an enzyme involved in tryptophan catabolism, has been linked with tumor survival and poor prognosis of brain and breast cancer. However, no studies have investigated the potential role of TDO2 in esophageal cancer. Here we explored the expression and biological significance of TDO2 in ESCC. Methods: TDO2 protein expression was evaluated in 90 ESCC tissue samples by immunohistochemistry. TDO2 function in ESCC cell lines and spheroid colony formation were evaluated by RNA interference (RNAi). Results: TDO2 overexpression was associated with tumor stage, recurrence status, and the CD44 cancer stem cell marker in ESCC. TDO2 overexpression was correlated with poor outcome of ESCC patients. Inhibition of TDO2 expression by RNAi in TE-10 and TE-11 cell lines reduced both the number and the size of spheroid colonies as well as cell proliferation. Knockdown of TDO2 expression also induced inactivation of the epidermal growth factor receptor signaling pathway. Conclusion: Our results imply that TDO2 could play an important role in the progression of ESCC. Furthermore, TDO2 may be a potential therapeutic target in ESCC.

Bladder cancer (BC) is a common malignancy worldwide. Signal peptidase complex 18 (SPC18) protein, which is encoded by the SEC11A gene, is one of the subunits of the signal peptidase complex and induces transforming growth factor-α secretion. In the present study, we analyzed the expression and function of SPC18 protein in human BC.Expression of SPC18 was analyzed by immunohistochemistry. RNA interference was used to inhibit SEC11A expression in BC cell lines. For constitutive expression of the SEC11A gene, a SEC11A expression vector was transfected into BC cell lines. To examine cell viability, we performed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Modified Boyden chamber assays were used to examine cell invasiveness.SPC18 was upregulated in 54% of 81 BC cases. SPC18 expression served as an independent prognostic classifier of patients with BC. SPC18-positive BC cases frequently expressed cytokeratin 5/6, a marker of basal-like BC. Cell growth and invasiveness were inhibited by SEC11A knockdown and enhanced by forced expression of SEC11A.These results indicate that SPC18 plays an important role in the progression of BC. Specific inhibitors of SPC18 may be promising anticancer drugs for patients with basal-like BC.

Purpose We compared gross characterization of intracranial dural arteriovenous fistulas (DAVFs) between unenhanced 3-tesla 3-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) and digital subtraction angiography (DSA). Methods We subjected 26 consecutive patients with intracranial DAVF to unenhanced 3T 3D TOF MRA and to DSA. Two independent sets of observers inspected the main arterial feeders, fistula site, and venous drainage pattern on MRA and DSA images. Interobserver and intermodality agreements were assessed by k statistics. Results Interobserver agreement was excellent for fistula site (κ = 0.919; 95% confidence interval [CI], 0.805 to 1.000), good for main arterial feeders (κ = 0.711; 95% CI, 0.483 to 0.984), and very good for venous drainage (κ = 0.900; 95% CI, 0.766 to 1.000). Intermodality agreement was excellent for fistula site (κ = 0.968; 95% CI, 0.906 to 1.000) and good for main arterial feeder (κ = 0.809; 95% CI, 0.598 to 1.000) and venous drainage (κ = 0.837; 95% CI, 0.660 to 1.000). Conclusion Gross characterization of intracranial DAVF was similar for both imaging modalities, but unenhanced 3T 3D TOF MRA cannot replace DSA.

Background Renal cell carcinoma (RCC) is one of the most common types of cancer in developed countries. Bone marrow stromal cell antigen 2 (BST2) gene, which encodes BST2 transmembrane glycoprotein, is overexpressed in several cancer types. In the present study, we analyzed the expression and function of BST2 in RCC. Materials and methods BST2 expression was analyzed by immunohistochemistry in 123 RCC cases. RNA interference was used to inhibit BST2 expression in a RCC cell line. Results Immunohistochemical analysis showed that 32% of the 123 RCC cases were positive for BST2. BST2 expression was positively associated with tumour stage. Furthermore, BST2 expression was an independent predictor of survival in patients with RCC. BST2 siRNA-transfected Caki-1 cells displayed significantly reduced cell growth and invasive activity relative to negative control siRNA-transfected cells. Conclusion These results suggest that BST2 plays an important role in the progression of RCC. Because BST2 is expressed on the cell membrane, BST2 is a good therapeutic target for RCC.

Rationale and Objectives For the evaluation of patients scheduled for the treatment of brain arteriovenous malformations (AVMs), accurate anatomical information is essential. The purpose of this study was to assess the usefulness of three-dimensional (3D) digital subtraction angiography (DSA)-magnetic resonance (MR) fusion imaging for the pretreatment evaluation of AVMs. Materials and Methods The study population consisted of 11 consecutive patients (7 males, 4 females; age 10–72 years; mean 45 years) with brain AVMs. All prospectively underwent pretreatment MR imaging (MRI), MR angiography (MRA), and two-dimensional (2D) and 3D DSA. The 3D DSA and MR images were semiautomatically fused with fusion software on a workstation. In the delineation of AVM nidus, feeder, drainer, and relationship between AVM and the adjacent brain structures, two radiologists independently evaluated MRA and MRI, three-dimensional (3D) DSA, and MRI, and 3D DSA-MR fusion images using a 4-point scoring system. The referring neurosurgeons were asked whether the information provided by 3D DSA-MR fusion images was helpful for treatment decisions. Results For all four items, the delineation was significantly better with the 3D DSA/MRI or 3D DSA-MR fusion images than the MRA/MRI images. Although the delineation for the nidus, feeder, and drainer were not significantly different between the 3D DSA/MRI and 3D DSA-MR fusion images, 3D DSA-MR fusion imaging were significantly better for the relationship between AVM and the adjacent brain structures than 3D DSA/MR imaging ( P = .0047). The information provided by 3D DSA-MR fusion images was helpful for treatment decisions in all cases. Conclusion 3D DSA-MR fusion images are useful for the pretreatment evaluation of brain AVMs.

BACKGROUND AND PURPOSE: For identifying the arterial feeders of meningiomas, the usefulness of 3D TOF MRA at 3T has not been systematically investigated. This study was intended to assess whether unenhanced 3D TOF MRA at 3T can replace DSA for the identification of arteries feeding intracranial meningiomas and whether it is useful for assessing their dural attachment. MATERIALS AND METHODS: Twenty-one consecutive patients with intracranial meningiomas (18 women, 3 men; aged 42–77 years, mean 57 years) underwent DSA, conventional MR imaging, and 3D TOF MRA. Two neuroradiologists independently evaluated the primary and secondary feeders of each tumor on maximum-intensity-projection and source MRA images. They also identified the location of dural attachments based on information from MR imaging/MRA images. Interobserver and intermodality agreement was determined by calculating the κ coefficient. RESULTS: For the identification of primary and secondary feeders on MRA images, interobserver agreement was very good (κ = 0.83; 95% CI, 0.66–1.00) and moderate (κ = 0.58; 95% CI, 0.34–0.82) and intermodality agreement (consensus reading of MRA versus DSA findings) was excellent (κ = 0.94; 95% CI, 0.84–1.00) and good (κ = 0.72; 95% CI, 0.51–0.93), respectively. With respect to the dural attachment of meningiomas, interobserver agreement was very good (κ = 0.95; 95% CI, 0.84–1.00). The agreement in the diagnosis between MR imaging/MRA and surgery was excellent (κ = 1.00). CONCLUSIONS: Unenhanced 3D TOF MRA at 3T cannot at present supplant DSA for the identification of the feeding arteries of intracranial meningiomas. This information may be useful for evaluating their dural attachment.

BACKGROUND AND PURPOSE: QUASAR is a particular application of the ASL method and facilitates the user-independent quantification of brain perfusion. The purpose of this study was to assess the intermodality agreement of TBF measurements obtained with ASL and DSC MR imaging and the inter- and intraobserver reproducibility of glioma TBF measurements acquired by ASL at 3T. MATERIALS AND METHODS: Two observers independently measured TBF in 24 patients with histologically proved glioma. ASL MR imaging with QUASAR and DSC MR imaging were performed on 3T scanners. The observers placed 5 regions of interest in the solid tumor on rCBF maps derived from ASL and DSC MR images and 1 region of interest in the contralateral brain and recorded the measured values. Maximum and average sTBF values were calculated. Intermodality and intra- and interobsever agreement were determined by using 95% Bland-Altman limits of agreement and ICCs. RESULTS: The intermodality agreement for maximum sTBF was good to excellent on DSC and ASL images; ICCs ranged from 0.718 to 0.884. The 95% limits of agreement ranged from 59.2% to 65.4% of the mean. ICCs for intra- and interobserver agreement for maximum sTBF ranged from 0.843 to 0.850 and from 0.626 to 0.665, respectively. The reproducibility of maximum sTBF measurements obtained by methods was similar. CONCLUSIONS: In the evaluation of sTBF in gliomas, ASL with QUASAR at 3T yielded measurements and reproducibility similar to those of DSC perfusion MR imaging.

The purpose of this study was to evaluate whether cerebral perfusion from bypassed arteries can be demonstrated on regional perfusion imaging (RPI) using arterial spin labeling. We then compared cerebral perfusion on RPI and digital subtraction angiography (DSA) in moyamoya patients who underwent extracranial-intracranial bypass surgery. We performed RPI using a 3-T magnetic resonance scanner and DSA studies in 11 moyamoya patients treated by bypass surgery. For RPI we placed a selective labeling slab on the bypassed external carotid artery. Two neuroradiologists determined the extent and location of the cerebral perfusion from bypass arteries in the middle cerebral artery territories on RPI and DSA. Kappa analysis was used to assess the interobserver agreement with respect to the extent and location of the cerebral perfusion and to evaluate the intermodality agreement between RPI and DSA. Interobserver agreement for the extent of cerebral perfusion on RPI was very good (kappa = 0.89), with excellent location (kappa = 1.00). Intermodality agreement for the extent of perfusion was very good (kappa = 0.89), with good location (kappa = 0.74). RPI is useful for evaluating cerebral perfusion from bypass arteries in moyamoya patients.

We applied multivariate analysis to the clinical findings in patients with acute gastrointestinal (GI) hemorrhage and compared the relationship between these findings and angiographic evidence of extravasation. Our study population consisted of 46 patients with acute GI bleeding. They were divided into two groups. In group 1 we retrospectively analyzed 41 angiograms obtained in 29 patients (age range, 25-91 years; average, 71 years). Their clinical findings including the shock index (SI), diastolic blood pressure, hemoglobin, platelet counts, and age, which were quantitatively analyzed. In group 2, consisting of 17 patients (age range, 21-78 years; average, 60 years), we prospectively applied statistical analysis by a logistics regression model to their clinical findings and then assessed 21 angiograms obtained in these patients to determine whether our model was useful for predicting the presence of angiographic evidence of extravasation. On 18 of 41 (43.9%) angiograms in group 1 there was evidence of extravasation; in 3 patients it was demonstrated only by selective angiography. Factors significantly associated with angiographic visualization of extravasation were the SI and patient age. For differentiation between cases with and cases without angiographic evidence of extravasation, the maximum cutoff point was between 0.51 and 0.0.53. Of the 21 angiograms obtained in group 2, 13 (61.9%) showed evidence of extravasation; in 1 patient it was demonstrated only on selective angiograms. We found that in 90% of the cases, the prospective application of our model correctly predicted the angiographically confirmed presence or absence of extravasation. We conclude that in patients with GI hemorrhage, angiographic visualization of extravasation is associated with the pre-embolization SI. Patients with a high SI value should undergo study to facilitate optimal treatment planning.

Objective We aimed to assess the usefulness of 3-T 4-dimensional (4D) arterial spin-labeling (ASL)-based magnetic resonance angiography (MRA) with color-coded time-of-arrival (TOA) maps for the evaluation of cerebral arteriovenous malformations (AVMs). Methods Our study included 6 patients with cerebral AVMs. They underwent 4D-ASL MRA at 3T and digital subtraction angiography. A pseudocontinuous arterial spin labeling protocol with look-locker sampling was used for spin labeling. Two independent readers reviewed the 4D-ASL MRA images with color-coded TOA maps for the nidus size, arterial feeders, and venous drainage. Two other readers consensually reviewed the digital subtraction angiography images. Results The cerebral AVMs were demonstrated on all 4D-ASL MRA images. In 5 high-flow AVMs, the color-coded TOA maps were especially useful for identifying the feeder/drainer. Intermodality agreement was excellent for the nidus size (κ = 1.0), very good for arterial feeders (κ = 0.88), and good for venous drainage (κ = 0.80). Conclusions The 4D-ASL 3-T MRA with color-coded TOA maps is useful for assessing the gross angiographic characteristics of intracranial AVMs.

Adult T-cell leukaemia (ATL) is a T-cell lymphoid neoplasm caused by human T-cell leukaemia virus type I (HTLV-I). Radiological findings in central nervous system (CNS) involvement have not been well characterised. We reviewed the MRI of 18 patients with ATL who developed new neurological symptoms or signs, and pathology specimens from a 53-year-old woman who died of ATL. MRI findings were divided into three categories: definite, probable, and other abnormal. Definite and probable findings were defined as ATL-related. The characteristic findings were multiple parenchymal masses with or without contrast enhancement adjacent to cerebrospinal fluid (CSF) spaced and the deep grey matter of both cerebral hemispheres, plus leptomeningeal lesion. One patient had both cerebral and spinal cord lesions. Other abnormal findings in eight patients included one case of leukoencephalopathy caused by methotrexate. The histology findings consisted of clusters of tumour cells along perivascular spaces, and scattered infiltration of the parenchyma, with nests of tumour cells. Leptomeningeal infiltration by tumour spread into the parenchyma and secondary degeneration of the neuronal tracts was observed. MRI was useful for detecting CNS invasion by ATL and differentiating it from other abnormalities. The MRI findings seemed to correlate well with the histological changes.

Aim To evaluate whether 3-T four-dimensional (4D) arterial spin-labelling (ASL) -based magnetic resonance angiography (MRA) is useful for assessing the collateral circulation via the circle of Willis in patients with carotid artery steno-occlusive disease. Materials and methods Institutional review board approval and prior written informed consent from all patients were obtained. The inclusion criteria were fulfilled by 13 patients with carotid artery steno-occlusive disease. All underwent 4D-ASL MRA at 3 T and digital subtraction angiography (DSA). The flow-sensitive alternating inversion recovery (FAIR) preparation scheme with look-locker sampling was used for spin labeling. At 300-ms intervals seven dynamic scans were obtained with a spatial resolution of 0.5×0.5×0.6 mm 3 . The collateral flow via the circle of Willis was read on 4D-ASL MRA and DSA images by two sets of two independent readers each. κ statistics were used to assess interobserver and intermodality agreement. Results On DSA, collateral flow via the anterior communicating artery (AcomA) was observed in six patients, via the posterior communicating artery (PcomA) in four patients, and via both the AcomA and PcomA in three patients. With respect to the qualitative evaluation of 4D-ASL MRA images, interobserver agreement was excellent for all items (κ=1). 4D-ASL MRA and DSA consensus readings agreed on the type of collateral flow pattern in 10 of the 13 patients (77%). Intermodality agreement was good (κ=0.606; 95% confidence interval (CI): 0.215–0.997). Conclusion 3 T 4D-ASL MRA may be a useful tool for the evaluation of the collateral circulation in patients with carotid artery steno-occlusive disease.

Our purpose was to evaluate and compare the performance of ultra-fast single-shot T2-weighted sequences: echo-planar imaging (EPI) versus half-Fourier single-shot turbo spin-echo (HASTE) and to assess the usefulness of their combined reading. Comparative experiments on a phantom as well as a prospective clinical study in 47 patients were done. Axial images acquired with the following methods were compared: (a) HASTE; (b) segmented HASTE (s-HASTE); (c) single-shot spin-echo EPI (SE-EPI); and (d) gradient-echo EPI (GREEPI). Quantitative and qualitative criteria as well as lesion detectability were analyzed against the "gold standard" fast spin-echo (FSE) sequence. For contrast and contrast-to-noise ratio (CNR) between gray and white matter, GRE-EPI was best. The visibility of small markedly hyperintense lesion was best with HASTE and s-HASTE in the clinical study. Small hyperintense lesions were detected equally well with all four sequences, although all performed significantly worse than FSE. The two HASTE variants were better than the EPIs for the extraaxial lesions. The combination of the GRE-EPI and s-HASTE was judged best, and sometimes superior to the FSE image. HASTE or EPI alone cannot substitute for FSE in the screening evaluation of the brain. However, together, EPI and HASTE could provide comparable diagnostic information to that of FSE because their combination compensates for their individual limitations.

The purpose of this study was to evaluate a three-dimensional (3D) constructive interference in steady state (CISS) sequence in the assessment of syringomyelia. Eleven patients with syringomyelia were prospectively studied with magnetic resonance imaging. All patients underwent sagittal imaging with T1- and T2-weighted spin-echo (SE), and 3D-CISS sequences. The SE and 3D-CISS images, as well as multiplanar reconstruction (MPR) images of the 3D-CISS sequence, were analyzed with regard to image quality, degree of artifacts, visualization of the extent and internal structure of the syringomyelia, and contrast-to-noise ratio (CNR) of the fluid within the syringomyelia. Contrast between the spinal cord and cerebrospinal fluid (CSF), as well as delineation was significantly poorer for the T1-weighted SE sequence than for the 3D-CISS sequence (P < 0.01), while there was no significant difference between the T2-weighted SE sequence and the 3D-CISS sequence. Artifacts induced by CSF flow were significantly more for the T2-weighted SE sequence than for the 3D-CISS sequence (P < 0.01). Although the extent of syringomyelia was delineated equally among the three sequences in 9 of 11 patients, it was better for the 3D-CISS sequence than for the SE sequences in the remaining two. Septation and communication between the cavities were best detected by the 3D-CISS MPR images. The CNR of the 3D-CISS sequence was significantly higher than that of the SE sequences (P < 0.01). The 3D-CISS sequence demonstrates the extent and internal structures of syringomyelia better than conventional SE sequences and should be added to SE sequences in the evaluation of syringomyelia. J. Magn. Reson. Imaging 2000;11:120–126. © 2000 Wiley-Liss, Inc.

This work investigated whether turbo magnetic resonance angiography (MRA) can replace conventional MRA in screening examination of intracranial arteries. A phantom was used to evaluate the effect of the zero-filling interpolation (ZFI) technique on spatial resolution and partial volume effect. Thirty-one consecutive patients underwent both turbo MRA with a slice thickness of 0.7 mm (data were measured as 1.33 mm sections) and conventional MRA with 1.0 mm sections. In the phantom studies, ZFI did not improve the spatial resolution, but the partial volume effect was somewhat reduced. In the clinical evaluation, turbo MRA showed better signal-to-noise and contrast-to-noise ratios of the intracranial major vessels than conventional MRA. The lesions included cerebral aneurysms less than 3 mm in diameter, occlusive vascular disease, arteriovenous malformations, and arteriovenous fistulas. These were all depicted on both turbo MRA and conventional MRA. Turbo MRA is a useful screening procedure because of its capability of delineating lesions in approximately half the usual imaging time. J. Magn. Reson. Imaging 1999;10:939-944.

Purpose: To date, there have been no systematic reports examining cerebral lymphomas with perfusion-sensitive MRI. We sought to determine the characteristics of perfusion-sensitive MRI of these tumors. Method: Five primary and three secondary cerebral lymphomas were analyzed. None of the patients had a history of AIDS. Various areas of relative cerebral blood volume (rCBV) within tumor were analyzed, and maximum CBV ratios (CBV[tumor/ contralateral]) were identified for evaluation. Results: In three primary and three secondary cerebral lymphomas, maximum CBV ratios were

Purpose The purpose of this work was to assess the changes of signal intensity on constructive interference in steady state (CISS) 3D Fourier transformation (3DFT) MRI after administration of Gd-DTPA and to evaluate the efficacy of contrast-enhanced CISS-3DFT MRI to depict the seventh and eighth cranial nerves affected by vestibular schwannomas. Method All scans were carried out on a 1.5 T MR unit. First, an experimental study was conducted to evaluate the changes in signal intensity of the CISS-3DFT sequence in relation to the concentration of contrast medium. Second, nine consecutive patients with 11 vestibular schwannomas underwent CISS-3DFT imaging before and after contrast agent administration. Signal intensities of the tumors and nerves were measured and compared between the pre- and postcontrast images. Visualization of the facial and cochlear nerves was rated on pre- and postcontrast CISS imaging independently. Results On the phantom study, the CISS-3DFT sequence showed a constant increase in signal intensity as the concentration of Gd-DTPA increased. The contrast between the nerves and tumors significantly increased after contrast agent administration (from 0.1 to 9.0 as mean contrast-to-noise ratio). The ability to depict the nerves was also significantly higher for postcontrast CISS-3DFT imaging than for precontrast. Conclusion Although the CISS-3DFT sequence offers similar contrast as other heavily T2-weighted sequences, the signal intensity of contrast-enhanced tumors increased on CISS-3DFT imaging. Contrast-enhanced CISS imaging was valuable for evaluating the seventh and eighth cranial nerves affected by vestibular schwannomas.

Our purpose was to evaluate the relationships between the ratio of maximum relative cerebral blood volume (rCBV) (rCBV ratio = rCBV[tumor]/rCBV[contralateral white matter]) and histologic and angiographic vascularities of gliomas using the gradient-echo echoplanar MR imaging technique. We also evaluated the usefulness of rCBV maps for grading gliomas.We examined 30 patients with histologically verified gliomas. Gliomas were classified as glioblastoma, anaplastic glioma with enhancement, anaplastic glioma without enhancement, and low-grade glioma. The maximum rCBV ratio of each glioma was compared with both histologic and angiographic vascularities, and the relationship between the maximum rCBV ratios and each type of glioma was established.The maximum rCBV ratios of the gliomas significantly correlated with both histologic and angiographic vascularities (p.001). Mean values and SDs of maximum rCBV ratios of each type of tumor were 7.32+/-4.39 for glioblastomas, 5.84+/-1.82 for anaplastic gliomas with enhancement, 1.53+/-0.75 for anaplastic gliomas without enhancement, and 1.26+/-0.55 for low-grade gliomas. The maximum rCBV ratios of the glioblastomas were significantly higher than those of the anaplastic gliomas without enhancement (p = .002) and the low-grade gliomas (p.001). The maximum rCBV ratios of the anaplastic gliomas with enhancement were higher than those of the anaplastic gliomas without enhancement and the low-grade gliomas, but the differences were not statistically significant (p = .08 and p = .03, respectively).The results of perfusion-sensitive MR imaging with gradient-echo echoplanar technique correlated with both histologic and angiographic vascularities.

We used constructive interference in steady state (CISS) 3D Fourier transform (3DFT) MRI data sets to obtain three-dimensional (3D) virtual MRI endoscopic views of the intracranial cerebrospinal fluid (CSF) spaces, processing them with a commercially available perspective endoscopic algorithm. We investigated the potential of the intracranial virtual MRI endoscopy applied to visualisation of the pathology in 13 patients with surgically confirmed trigeminal neuralgia (3), hemifacial spasm (3), acoustic neuroma (3), suprasellar germinoma (1), Langerhans cell histiocytosis (1), lateral ventricle nodules (1) and pituitary dwarfism (1). All images were acquired using a 1.5-T imager employing a circular polarised head coil. The CISS-3DFT data sets were transferred to a workstation for processing with the perspective endoscopic algorithm. Postprocessing for virtual MRI endoscopy was possible for all data sets. The lesions in 12 patients, and their complex anatomical relationships with the surrounding structures, were well seen on the 3D images. A small acoustic neuroma in the internal auditory meatus was not seen using virtual endoscopy. Although virtual MRI endoscopy has limitations, it provides 3D images which cannot be acquired using any other procedure.

The aim of this study was to assess the efficacy of CT angiography for steno-occlusive diseases before and after interventional procedures, focusing on the role of multiplanar reconstruction (MPR) and source images. 17 patients with 20 steno-occlusive lesions underwent CT angiography before and after interventional procedures. For each lesion, the percentage stenosis obtained on CT angiography was compared with that on conventional angiography. In addition, MPR and source images were evaluated for the presence of wall thickening and calcification before interventional procedures, and the presence of dissection and luminal shape after interventional procedures. These findings were compared with those of conventional angiography. Although the percentage stenosis depicted on CT angiography correlated well with that on conventional angiography, MPR and source images clearly demonstrated the effect of intervention and the residual stenosis. MPR and source images clearly depicted wall thickening, wall calcification, the presence of dissection and the luminal shape. CT angiography provides useful information before intervention, while MPR and source images are of value in evaluating arterial wall abnormalities and morphological changes associated with interventional procedures.

To evaluate whether 3-T four-dimensional (4D) arterial spin-labeling (ASL)-based magnetic resonance (MR) angiography is useful for the evaluation of shunt lesions in patients with intracranial dural arteriovenous fistulas (AVFs).Institutional review board approval and prior written informed consent from all patients were obtained. Nine patients with intracranial dural AVF (seven men, two women; age range, 52-77 years; mean age, 63 years) underwent 4D ASL MR angiography at 3 T and digital subtraction angiography (DSA). Spin tagging was with flow-sensitive alternating inversion recovery with Look-Locker sampling. At 300-millisecond intervals, seven dynamic images with a spatial resolution of 0.5 × 0.5 × 0.6 mm(3) were obtained. The 4D ASL MR angiographic and DSA images were read by two sets of two independent readers each. Interobserver and intermodality agreement was assessed with the κ statistic.On all 4D ASL MR angiographic images, the major intracranial arteries were demonstrated at a temporal resolution of 300 milliseconds. Interobserver agreement was excellent for the fistula site (κ = 1.00; 95% confidence interval [CI]: 1.00, 1.00), moderate for the main arterial feeders (κ = 0.53; 95% CI: 0.08, 0.98), and good for venous drainage (κ = 0.77; 95% CI: 0.35, 1.00). Intermodality agreement was excellent for the fistula site and venous drainage (κ = 1.00; 95% CI: 1.00, 1.00) and good for the main arterial feeders (κ = 0.80; 95% CI: 0.58, 1.00).The good-to-excellent agreement between 3-T 4D ASL MR angiographic and DSA findings suggests that 3-T 4D ASL MR angiography is a useful tool for the evaluation of intracranial dural AVFs.

BACKGROUND AND PURPOSE: For the localization of spinal dural arteriovenous fistulas, it is not determined whether dynamic contrast-enhanced MRA is more reliable than multidetector CTA. The aim of this study was to compare the agreement between intra-arterial DSA, dynamic contrast-enhanced MRA at 3T, and 64-row multidetector CTA for the localization of spinal dural arteriovenous fistulas. MATERIALS AND METHODS: We enrolled 12 consecutive patients (11 men, 1 woman; age range, 46–83 years; mean, 65 years) who underwent preoperative dynamic contrast-enhanced MRA at 3T and 64-row multidetector CTA. The spinal dural arteriovenous fistula location was confirmed by intra-arterial DSA as the reference standard. Two reviewers independently evaluated the level of the artery feeding the spinal dural arteriovenous fistula on the basis of continuity between the feeder and abnormal spinal vessels on 3T dynamic contrast-enhanced MRA and 64-row multidetector CTA images. Interobserver and intermodality agreement was determined by calculation of the κ coefficient. RESULTS: On DSA, the vessel feeding the spinal dural arteriovenous fistula was the intercostal artery (7 cases), the lumbar artery (3 cases), and the internal iliac artery or the ascending pharyngeal artery (1 case each). For the fistula level, interobserver agreement was excellent for 3T dynamic contrast-enhanced MRA (κ = 0.97; 95% CI, 0.92–1.00) and very good for 64-row multidetector CTA (κ = 0.84; 95% CI, 0.72–0.96). Intermodality agreement with DSA was good for 3T dynamic contrast-enhanced MRA (κ = 0.78; 95% CI, 0.49–1.00) and moderate for 64-row multidetector CTA (κ = 0.41; 95% CI, 0.020–0.84). CONCLUSIONS: For the localization of spinal dural arteriovenous fistulas, 3T dynamic contrast-enhanced MRA may be more reliable than 64-row multidetector CTA.

OBJECTIVE: The purpose of this study was to determine how the gray-to-white matter contrast in healthy subjects changes on high-b-value diffusion-weighted imaging (DWI) acquired at 3 T and evaluate whether high-b-value DWI at 3 T is useful for the detection of cortical lesions in inflammatory brain diseases. METHODS: Ten healthy volunteers underwent DWI at b = 1000, 2000, 3000, 4000, and 5000 s/mm(2) on a 3-T MRI unit. On DW images, 1 radiologist performed region-of-interest measurements of the signal intensity of 8 gray matter structures. The gray-to-white matter contrast ratio (GWCR) was calculated. Ten patients with inflammatory cortical lesions were also included. All patients underwent conventional MRI and DWI at b = 1000 and 3000 s/mm(2). Using a 4-point grading system, 2 radiologists independently assessed the presence of additional information on DW images compared with fluid-attenuated inversion recovery images. Interobserver agreement was assessed by κ statistics. RESULTS: In the healthy subjects, the b value increased as the GWCR decreased in all evaluated gray matter structures. On DW images acquired at b = 3000 s/mm(2), mean GWCR was less than 1.0 in 7 of 8 structures. For both reviewers, DWI at b = 3000 s/mm(2) yielded significantly more additional information than did DWI at b = 1000 s/mm(2) (P < 0.05). Interobserver agreement for DWI at b = 1000 s/mm(2) and b = 3000 s/mm(2) was fair (κ = 0.35) and excellent (κ = 1.0), respectively. CONCLUSIONS: At 3-T DWI, the gray-to-white matter contrast in most gray matter structures reverses at b = 3000 s/mm. In the evaluation of cortical lesions in patients with inflammatory brain diseases, 3-T DWI at b = 3000 s/mm was more useful than b = 1000 s/mm(2).

BACKGROUND AND PURPOSE: Systematic assessment of brain and head and neck tumors with 4D-CE-MRA at 3T has not been investigated. The purpose of this study was to test the hypothesis that 4D-CE-MRA at 3T can replace DSA in the identification of feeding arteries and tumor stain to plan interventional procedures in hypervascular brain and head and neck tumors. MATERIALS AND METHODS: Fifteen consecutive patients with brain and head and neck tumors underwent 4D-CE-MRA at 3T and DSA. 4D-CE-MRA combined randomly segmented central k-space ordering, keyhole imaging, SENSE, and half-Fourier imaging. We obtained 30 dynamic scans every 1.9 seconds at an acquired spatial resolution of 0.9 × 0.9 × 1.5 mm; the matrix was 256 × 256. Two independent observers inspected the 4D-CE-MRA images for the main arterial feeders and tumor stain. Interobserver and intermodality agreement was assessed by κ statistics. RESULTS: For 4D-CE-MRA, the interobserver agreement was fair with respect to the main arterial feeders and very good for the degree of tumor stain (κ = 0.28 and 0.87, respectively). Intermodality agreement was moderate for the main arterial feeders (κ = 0.45) and good for the tumor stain (κ = 0.74). CONCLUSIONS: Although 4D-CE-MRA may be useful for evaluating tumor stain in hypervascular brain and head and neck tumors, it is not able to replace DSA in planning interventional procedures.

BACKGROUND AND PURPOSE: Although 3D FLAIR imaging visualizes detailed structures of the brain stem, it has not been used to evaluate its normal anatomy. The purpose of this study was to evaluate whether 3D FLAIR images can provide more detailed anatomic information of the brain stem than 2D FLAIR and 2D T2WI. MATERIALS AND METHODS: We prospectively evaluated MR images in 10 healthy volunteers. 3D and 2D FLAIR images, 2D T2WI, and DTI were obtained on a 3T MR imaging scanner. A VISTA technique was used for 3D FLAIR imaging. White matter tracts and nuclei of the brain stem were determined on 3D and 2D FLAIR images and 2D T2WI by referring to anatomic atlases and DTI color maps. The subjective assessment of the visibility by using a 4-point grading system and the contrast ratio of the structures on 3D and 2D FLAIR images and 2D T2WI were evaluated. RESULTS: The visibility of the SCP and MCP, DSCP, CST, and CTT was higher on 3D FLAIR images than on 2D T2WI and 2D FLAIR images. The contrast ratio for the CST, SCP, MCP, DSCP, and CTT was significantly different on 3D FLAIR images and 2D T2WI and on 3D FLAIR and 2D FLAIR images; there was no significant difference in contrast ratio for the SCP at the pons on 3D FLAIR and 2D T2WI. CONCLUSIONS: 3D FLAIR images provide detailed anatomic information of the brain stem that cannot be obtained on 2D T2WI and 2D FLAIR images.

It is sometimes difficult to distinguish between primary central nervous system lymphomas (PCNSL) and glioblastoma multiforme (GBM). The aim of this study was to investigate whether the addition of (18)F-2-fluoro-2-deoxy-D: -glucose positron emission tomography ([(18)F]FDG-PET) and apparent diffusion coefficients (ADC) to conventional MRI improves diagnostic accuracy for distinguishing between PCNSL and GBM with similar MRI findings.We used conventional- and diffusion-weighted MRI and FDG-PET scans of 21 patients with histologically confirmed brain tumors exhibiting similar MRI findings (PCNSL, n = 14, GBM, n = 7) in our observer performance study that consisted of 3 interpretation sessions. ADC and maximum standard uptake values (SUV(max)) of the tumors were calculated. Three radiologists first interpreted conventional MRI (1st session), then they read images to which the ADC value had been added (2nd session), and finally they interpreted images supplemented with SUV(max) (3rd session). Observer performance was evaluated using κ statistic and receiver operating characteristics analyses.The addition of ADC values to conventional MRI failed to improve the differentiation between PCNSL and GBM. The addition of SUV(max) at the third session improved the diagnostic accuracy of all 3 readers and resulted in higher interobserver agreement; mean accuracy was 95% (range 93-100%). In one observer the accuracy of tumor differentiation was significantly improved at the third compared to the second session (p = 0.017).In a selected group of PCNSL and GBM with similar MRI findings, the addition of quantitative FDG-PET to MRI may improve their differentiation. ADC measurement did not allow further discrimination.

BACKGROUND AND PURPOSE: The usefulness of contrast-enhanced 3D T2-FLAIR MR imaging for the evaluation of leptomeningeal diseases has not been systematically investigated. The purpose of this study was to assess the value added by contrast-enhanced 3D T2-FLAIR and MPRAGE sequences to conventional postcontrast T1-weighted images in the evaluation of leptomeningeal diseases. We also undertook in vitro studies in attempts to understand the consequences of our patient study. MATERIALS AND METHODS: Twelve patients with confirmed leptomeningeal diseases underwent postcontrast T1-weighted, MPRAGE, and 3D T2-FLAIR imaging at 3T. Two radiologists independently assessed the presence of additional information on postcontrast 3D MR images compared with postcontrast T1-weighted images. The effect of different Gd concentrations and flow velocities on the signal intensity on 3D T2-FLAIR images was investigated in vitro. RESULTS: According to both reviewers, 3D T2-FLAIR images yielded significantly more information than did MPRAGE images (P < .05 and P < .01, respectively). In the in vitro study, 3D T2-FLAIR was more highly sensitive to low Gd concentrations and less sensitive to high Gd concentrations than were T1-weighted or MPRAGE sequences. On 3D T2-FLAIR sequences, at a flow velocity exceeding 1.0 cm/s, the signal intensity of blood-mimicking fluids at concentrations of 0 and 0.1 mmol/L was as low as at 1.3 mmol/L. CONCLUSIONS: For the depiction of leptomeningeal diseases, postcontrast 3D T2-FLAIR provides more additional information than postcontrast MPRAGE imaging. The superiority of the 3D T2-FLAIR sequence is associated with its high sensitivity to flow.

Source images from three-dimensional time-of-flight MR angiography (3D TOF MRA) are useful for the diagnosis of cavernous dural arteriovenous fistulas. The purpose of this study was to assess the accuracy of source images from 3D TOF MRA compared with digital subtraction angiography (DSA) as a follow-up technique for the detection of residual or recurrent fistulas after treatment. We also assessed the effect of embolized materials in the evaluation of MRA.In 14 patients who were treated with embolization and/or radiation therapy, follow-up MRA and DSA were performed after a mean follow-up duration of 3 months. Two observers independently reviewed the source images from MRA in regard to the presence of hyperintense regions within the cavernous sinus and enlargement of the draining veins. They also assessed whether embolized materials affected the evaluation.Sensitivity, specificity, and positive predictive value of source images from MRA in revealing residual or recurrent fistulas were 100% (9 of 9 true positive findings), 80% (4 of 5 true negative findings), and 90% (9 of 10 positive findings), respectively. In all five patients treated with platinum coils, hypointense areas in the cavernous sinus were observed but did not affect image evaluation.Source images from 3D TOF MRA provided accurate diagnosis with no effect of embolized materials in the follow-up of treated cavernous dural arteriovenous fistulas.

BACKGROUND AND PURPOSE: If venous congestion is the primary cause of pituitary gland enlargement in cases of dural arteriovenous fistulas (AVFs), other abnormal pituitary findings may be detectable on MR images. We sought to investigate the perfusion abnormality of the pituitary gland secondary to dural AVFs in the cavernous sinus and to clarify its clinical importance. METHODS: Nine consecutive patients (all female; age range, 50–77 years) with dural AVFs in the cavernous sinus underwent prospective MR examinations, including dynamic studies, before and after therapy. Their clinical signs and symptoms were recorded. Two radiologists visually evaluated the enhancement patterns of the anterior pituitary gland. Dynamic MR curves were obtained by locating regions of interest at the center and bilateral peripheral areas of the anterior pituitary gland on coronal images. MR images obtained in five healthy individuals served as controls. RESULTS: No patient had symptoms of hypopituitarism or other endocrine abnormalities. Asymmetric pituitary enhancement was found in five patients; the side with the dural AVF was less enhancing. This finding disappeared after therapy. Although asymmetric enhancement was not detected in the remaining four patients, statistical analysis showed significantly delayed enhancement of the pituitary gland in the patients compared with enhancement patterns in control subjects. After treatment, this delay improved significantly. The pituitary gland significantly decreased in size after treatment. CONCLUSION: Perfusion of the pituitary gland is impaired in patients with a dural AVF in the cavernous sinus. This finding is probably due to venous congestion of the pituitary gland caused by high pressure in the cavernous sinus; it is usually not related to pituitary dysfunction.

BACKGROUND AND PURPOSE: The potential pitfalls in the diagnosis of dural sinus thrombosis include the presence of arachnoid granulations, intrasinus fibrotic bands (so-called septa), and hypoplasia or aplasia of the dural sinuses. The purpose of this study was to assess the appearance, distribution, and prevalence of arachnoid granulations and septa in the dural sinuses by using a high resolution 3D contrast-enhanced magnetization prepared rapid acquisition gradient-echo (MPRAGE) imaging sequence. METHODS: Conventional MR images and contrast-enhanced MPRAGE images of 100 consecutive patients who had no abnormalities of the dural sinuses were retrospectively reviewed. The incidence, site, number, size, signal intensity, and shape of arachnoid granulations and septa within the sinuses and their relationship with adjacent veins were recorded. RESULTS: With 3D contrast-enhanced MPRAGE imaging, 433 round, oval, or lobulated focal filling defects were found in a total of 90 patients. Curvilinear septa were observed in 92 patients. Sixty-nine patients had round, oval, or lobulated defects in the transverse sinus, 59 had such defects in the superior sagittal sinus, and 47 had such defects in the straight sinus. All except two of the above defects were isointense relative to CSF on all images. These structures were presumed to be arachnoid granulations. Of 431 arachnoid granulations, 233 (53.8%) were located in the superior sagittal sinus, 122 (28.1%) in the transverse sinus, and 76 (17.6%) in the straight sinus. One or more veins were seen to enter arachnoid granulations in 414 (96%) instances. CONCLUSION: The contrast-enhanced 3D MPRAGE imaging sequence showed a much higher prevalence and a different distribution of arachnoid granulations and septa within dural sinuses than have been observed in previous radiologic studies. Arachnoid granulations were closely related spatially to veins.

Our aim was to review the MRI appearances of primary intracranial germ-cell tumours (GCT). We reviewed the MRI studies of 32 patients: 19 with germinomas, five with teratomas, one with an embryonal carcinoma, five with mixed and two with malignant nongerminomatous GCT. Eleven were in the pineal region, 12 suprasellar, five in the both sites, two in the basal ganglia and two in the corpus callosum. Contrast-enhanced images were available for 27 patients. The solid parts of GCT were nearly isointense with grey matter on both T1- and T2-weighted images. In seven patients with nongerminomatous GCT high-signal components were found on T1-weighted images, representing haemorrhage, high-protein fluid or fat. Cystic components were detected in 17 of 27 patients; eight germinomas and all nine nongerminomatous GCT had cysts. The solid components of germinomas enhanced homogeneously in eight cases and heterogeneously in 10, while all nongerminomatous GCT showed heterogeneous enhancement. MRI features tumours can facilitate correct diagnosis of GCT, including histological subtypes.

The purpose of this study is to assess the value of contrast-enhanced MP-RAGE sequence for evaluation of skull base tumors. A total of 36 patients were prospectively evaluated. MP-RAGE showed relatively higher CNRs than other sequences, and there was a significant difference of CNR between the MP-RAGE and contrast T1-weighted SE images when fat tissue was chosen as the background. MP-RAGE was significantly superior to other sequences in the diagnosis of the extent of tumors. Contrast-enhanced MP-RAGE sequence is useful in evaluation of skull base tumors because of its higher contrast, higher spatial resolution, multiplanar capability, and suppression of the fat signal.

Purpose: To investigate the MR dynamic patterns of neurohypophyseal germ cell tumors (GCTs) for differential diagnosis of infundibular diseases affecting young people. Material and Methods: Eleven patients with neurohypophyseal GCTs underwent dynamic MR studies with T1-weighted spin-echo (SE) or turbo SE techniques. Other infundibular lesions, including adenohypophysitis (n=3), Langerhans' cell histiocytosis (LCH, n=2), and 1 hemangioblastoma from von Hippel-Lindau disease, were also evaluated. Serial images were obtained every 15 s (turbo SE) or 30 s (SE technique) for 240 s after rapid injection of contrast medium. The dynamic patterns were analyzed quantitatively with the contrast medium enhancement ratio. Results: On dynamic MR images, GCTs typically showed a gradual enhancement increase with a peak between 105 s and 180 s, while two showed a relatively rapid increase. LCH and hemangioblastoma showed a dynamic pattern similar to GCTs, while adenohypophysitis demonstrated a sharp rise and a steeper wash-out with an obvious peak before 90 s. Conclusion: Typical dynamic pattern of GCTs was the gradual enhancement increase without wash-out. Dynamic MR imaging can distinguish GCTs from adenohypophysitis, but is not useful for differentiation from LCH.

The degree of tumor malignancy generally correlates to tumor grade, and the direct measurement of tumor vasculature is desired. Dynamic susceptibility contrast magnetic resonance imaging can provide relative cerebral blood volume and, therefore, is one of the most reliable methods to evaluate tumor vasculature in vivo. Tumor vessel size is extremely variable due to complex tumor angiogenesis, and the gradient-echo echo-planar imaging (GE-EPI) technique, which is sensitive to the total vascular bed, is well suited for this purpose. As many studies have shown, dynamic susceptibility contrast magnetic resonance imaging is more useful for grading glioma than conventional magnetic resonance imaging. We found that this technique can also provide supplementary information to differentiate between malignant lymphoma and glioma because the absence of tumor neovascularization of malignant lymphoma leads to low rCBV, which is in contrast to those of malignant gliomas. Indeed, this technique can be used for the differentiation of extra-axial tumors such as between meningioma and neurinoma. Recently, this technique has been focused toward determining the stereotactic biopsy site, monitoring the embolization of effect in meningioma, or evaluation of treatment effects after radiation therapy. However, the value of tumor rCBV is affected by many conditions such as the T1 relaxivity effects of gadolinium in the extravascular space. To establish the usefulness of this technique, further examination will be needed.

PURPOSE: To compare qualitatively and quantitatively the contrast of brain lesions detected with fluid-attenuated inversion-recovery (FLAIR) and intermediate-weighted sequences at magnetic resonance (MR) imaging. MATERIALS AND METHODS: In this prospective study, 47 patients suspected of having a brain lesion underwent MR imaging with FLAIR, intermediate-weighted, and T2-weighted sequences. Qualitative assessment was performed of lesion conspicuity, detection, overall image artifact, and additional clinical information. Contrast and contrast-to-noise ratio (CNR) were calculated between lesions and the normal brain or cerebrospinal fluid (CSF). RESULTS: FLAIR images were equal to intermediate-weighted images for overall lesion conspicuity and detection but were associated more often with image artifacts. Lesion-to-background contrast was significantly higher on FLAIR than on intermediate-weighted images. FLAIR images failed to demonstrate multiple sclerosis (MS) plaques located in the basal ganglia and brain stem. CONCLUSION: Although FLAIR images provided additional information in some cases, they did not have distinct advantages over intermediate-weighted images. When cases of MS are evaluated, intermediate-weighted images are preferable to FLAIR images. Except in cases of MS, either FLAIR or intermediate-weighted sequences should be added to T2-weighted sequences at MR imaging.

PURPOSE To compare MR imaging findings of the striate cortex with visual field deficits in patients with Minamata disease and to reestimate the classical Holmes retinotopic map by using the data obtained from comparing visual field abnormalities with degree of visual cortex atrophy. METHODS MR imaging was performed in eight patients with Minamata disease who had been given a full neuroophthalmic examination, including Goldmann dynamic perimetry. The atrophic portions of the calcarine area were measured in the sagittal plane next to the midsagittal image and represented as a percentage of atrophy of the total length of the calcarine fissure. MR findings were compared with results of a visual field test. RESULTS The visual field test revealed moderate to severe concentric constriction of the visual fields, with central vision ranging from 7 degrees to 42 degrees (mean, 19 degrees). The ventral portion of the calcarine sulcus was significantly dilated on MR images in all patients. A logarithmic correlation was found between the visual field defect and the extent of dilatation of the calcarine fissure. The central 10 degrees and 30 degrees of vision seemed to fill about 20% and 50% of the total surface area of the calcarine cortex, respectively. CONCLUSION Visual field deficits in patients with Minamata disease correlated well with MR findings of the striate cortex. Our data were consistent with the classical Holmes retinotopic map.

PURPOSE To study MR images for atrophic changes in the calcarine area resulting from retinal degeneration. METHODS MR images from nine patients with retinal degeneration confirmed by ophthalmologic examination and from 30 healthy volunteers were reviewed. The causes of retinal degeneration were hereditary pigmentary degeneration of the retina (four patients), high myopia (two patients), and chorioretinal atrophy (three patients); all patients had visual disturbances and visual field abnormalities. To estimate the morphological changes of the calcarine area, the widths of the right and left calcarine fissures were measured on T1-weighted sagittal images and compared with images from age-matched control subjects. RESULTS The calcarine fissures were significantly dilated in the patients with retinal degeneration. The anterior and middle points, which represent the peripheral visual field center, were more dilated than the posterior point. CONCLUSION The MR findings suggested calcarine atrophy related to retinal degeneration. Transneuronal degenerative changes may occur in the calcarine area after retinal degeneration.