The purpose of this study is to evaluate the capability of breast MRI (magnetic resonance imaging) and mammography in determining tumor extent and the detectability of ductal carcinoma in situ (DCIS) in association with histopathological features.
Thirty women with breast cancer underwent 3D dynamic MRI. Twelve women had pure DCIS and 18 women had DCIS with microinvasion. We analyzed the results of preoperative MRI and mammography with histopathologic results, retrospectively. The mean lesion size was 55.1 mm from the histopathologic results. Twenty-six lesions were detected through the MRI (a sensitivity of 86.7%). MRI depicted eight lesions without mammographically detected microcalcification. In seven cases, MRI showed tumor extent accurately compared with mammography, and the combined diagnosis improved the accuracy of evaluating tumor extent. MRI can complement mammography in guiding surgical treatment of DCIS by providing better assessment of the extent of the lesion.

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Purpose: The usefulness of fluid-attenuated inversion recovery (FLAIR) imaging for the evaluation of brain diseases has been reported. The purpose of this study was to evaluate the brain-meningioma interface with MRI including FLAIR imaging.
Materials and methods: This study involved 48 patients with 50 intracranial meningiomas. We retrospectively evaluated the brain-meningioma interface by various imaging method including FLAIR. If a thin layer with a signal intensity different from that of the tumor and brain was observed in the areas of the tumor-brain interface in T₁-weighted IR (T₁WIR) and T₂-weighted turbo SE (T₂WTSE) images, we defined this structure as the rim. The presence or absence of the rim and the signal intensity were evaluated, and the length and the signal intensity of the rim observed with FLAIR and contrast-enhanced T₁WIR (CE-T₁WIR) images were evaluated.
Results: In 35 of the 50 lesions (70.0%), the rim was observed in the tumor-brain interface as a layer of low signal intensity in T₁WIR images and high signal intensity in T₂WTSE images. In 13 lesions (26.0%), no rim was detected. Flow voids were observed at the tumor-brain interface in 20 of the 50 lesions (40.0%). No rim showed a low signal intensity of the tumor-brain interface in both T₁WIR and T₂WTSE images. The rim exhibited an iso-to-high signal intensity compared to the tumor parenchyma in FLAIR images and an enhanced signal intensity in CE-T₁WIR images. In contrast to T₁WIR images, the rim in FLAIR images tended to be identified across the entire circumference.
Conclusion: The rim at the brain-meningioma interface revealed as low signal intensity in T₁WIR images and high signal intensity in T₂WTSE images, which was conventionally considered to be the CSF cleft, was often revealed in FLAIR images as high signal intensity compared to the tumor parenchyma, and an enhanced signal intensity in CE-T₁WIR images. Therefore, the presence of CSF in such rims is unlikely, and the rims might reflect the capsule structure of the tumor surface.

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Objectives: The purpose of this study was to evaluate the usefulness of MRI (magnetic resonance imaging) and DSA (digital subtraction angiography) by using preoperative MRI and DSA findings in the examination of meningiomas before excision. In particular, we focused on their usefulness in predicting tumor-brain adhesion during surgery.
Materials and methods: The subjects were 36 patients with intracranial meningioma who underwent tumor excision at which time neurosurgeons examined the tumor-brain adhesion. Two neurosurgeons evaluated the degree of tumor-brain adhesion from operation records and videotapes recorded during surgery. Two neuroradiologists retrospectively evaluated the preoperative MRI findings including tumor diameter, signal intensity of the tumor parenchyma obtained with T₂-weighted imaging (T₂WI), characteristics of the tumor-brain interface, and degree of peritumoral brain edema. The vascular supply was also evaluated from the preoperative DSA findings. The relationship between these MRI and DSA findings and the degree of tumor-brain adhesion during surgery as classified by the neurosurgeons was statistically analyzed.
Results: The degree of peritumoral brain edema and the shapes and characteristics of the tumor-brain interface, including the findings of FLAIR (fluid-attenuated inversion recovery) imaging and vascular supply observed by DSA, were significantly correlated with tumor-brain adhesion. In particular, the shapes and characteristics of the tumor-brain interface as observed by T₁-weighted imaging (T₁WI), T₂WI, and FLAIR, respectively, as well as the vascular supply observed by DSA, were closely correlated with the degree of tumor-brain adhesion encountered during surgery. According to these results, we developed a method of predicting tumor-brain adhesion that considers the shape of the tumor-brain interface revealed by MRI and the vascular supply revealed by DSA.
Conclusions: We retrospectively examined the findings of MRI and DSA performed before excision of meningioma and clarified the relationship between the findings and tumor-brain adhesion. We speculated that tumor-brain adhesion can be accurately and simply predicted before surgery with a new method that considers the shape of the tumor-brain interface observed by MRI and vascular supply observed by DSA.

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Functional magnetic resonance imaging (fMRI) is now the method of choice for studying neural correlates of various tasks in normal subjects as well as patients. This method, however, is inevitably coupled with the acoustic noise produced during the image acquisition process. This is a problem not only in auditory experiments but also in other cognitive tasks in general. The problems caused by such noise are modulation of auditory activation, impaired perception of auditory stimuli, and deterioration of task performance possibly due to stress from the abnormal circumstances. While both hardware and software solutions have been reported, several methods are introduced here that focus on software solutions that can be implemented in scanners already installed. Their advantages and disadvantages differ depending on the kinds of tasks involved, i.e. whether block design or event-related design, and they are discussed with a view to better utilization.

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We constructed a gas polarization system to test the feasibility of using hyperpolarized ¹²⁹Xe gas as an NMR (nuclear magnetic resonance) probe to explore brain function. Both in vitro and in vivo experiments were performed with a 4.7T NMR spectrometer. Xenon spectra from human blood confirmed the existence of two peaks corresponding to red blood cells and plasma. In rat studies, three peaks at around 200 ppm were observed. Our results are consistent with previously reported data.

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We present magnetic resonance (MR) findings of siblings affected by spinal muscular atrophy (SMA) Type II. MRI of their thighs showed severe muscle atrophy and fatty infiltration. Selective preservation of the adductor longus muscle, the gracilis muscle, and the sartorius muscles was observed, suggesting a characteristic finding of SMA Type II. These findings were more severe in the older patient.

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Malignant fibrous histiocytoma (MFH) arising from the renal capsule is a rare tumor. We report a case of 55-year-old man with this tumor. Radiological imaging, including magnetic resonance (MR) imaging, was helpful in the differential diagnosis between MFH of the renal capsule and other renal tumors. In particular, a hypointense area identified on T₂-weighted images reflecting the fibrous component was identified as an important characteristic of renal MFH.

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