PURPOSE To determine the importance of obtaining precontrast T1-weighted magnetization transfer (MT) MR images for better interpretation contrast-enhanced T1-weighted MT images. METHODS One hundred fifty-five patients referred for MR imaging of the brain were examined prospectively with noncontrast T1-weighted imaging, noncontrast T1-weighted imaging with MT, contrast-enhanced T1-weighted ima...

BACKGROUND AND PURPOSE Pulsed arterial spin-labeling is a noninvasive MR imaging perfusion method performed with the use of water in the arterial blood as an endogenous contrast agent. The purpose of this study was to determine the inversion time with the largest difference in normalized intratumoral signal intensity between high-grade and low-grade astrocytomas. MATERIALS AND METHODS Thirty-...

BACKGROUND AND PURPOSE Intratumoral calcifications are very important in the diagnosis of retinoblastoma. Although CT is considered superior in detecting calcification, its ionizing radiation, especially in patients with hereditary retinoblastoma, should be avoided. The purpose of our study was to validate T2*WI for the detection of calcification in retinoblastoma with ex vivo CT as the criteri...

BACKGROUND AND PURPOSE Magic angle effects are well recognized in MR imaging of tendons and ligaments, but have received virtually no attention in MR neurography. We investigated the hypothesis that signal intensity from peripheral nerves is increased when the nerve's orientation to the constant magnetic induction field (B(0)) approaches 55 degrees (the magic angle). METHODS Ten volunteers we...

BACKGROUND AND PURPOSE Calcium can potentially shorten T1, generating high signal intensity in GREs. Because IPH appears as high signal intensity in MRIPH and the surface effects of calcium can potentially shorten T1 of surrounding water protons, the purpose of this study was to evaluate whether the high signal intensity seen on MRIPH could be attributed solely to IPH and not calcification. M...

BACKGROUND We previously demonstrated that superparamagnetic iron oxide (SPIO)-enhanced MR imaging is promising for the detection of metastases in sentinel nodes localized by CT-lymphography in patients with breast cancer. The purpose of this study was to determine the predictive criteria of the size of nodal metastases with SPIO-enhanced MR imaging in breast cancer, with histopathologic findin...

BACKGROUND AND PURPOSE The subplate layer and intermediate zone are the precursors for neonatal white matter. The aims of this study were to evaluate 1) T1 and T2 signal intensity, and 2) FA of subplate and intermediate zone in postmortem fetuses and correlate with histology, and 3) T2 signal intensity of subplate and intermediate zone on antenatal MR imaging. MATERIALS AND METHODS Fourteen i...

PURPOSE To compare the MR findings of eight cases with clinical diagnosis of Hallervorden-Spatz disease (HSD) with the pathologic findings of two other cases of HSD. MATERIALS AND METHODS The eight imaged cases were studied with 0.5-T (seven cases) and/or 1.5-T (five cases) units. Six patients also had CT scans. The two other cases with proven HSD had detailed histologic evaluation. RESULTS...

BACKGROUND AND PURPOSE Rathke's cleft cysts often may be difficult to differentiate from other intrasellar or suprasellar masses on radiologic studies. The purpose of this study was to describe the significance of intracystic nodules, a diagnostic characteristic found in Rathke's cleft cysts, on MR images. METHODS A retrospective review of MR studies was conducted for 13 patients who, after p...

Background: Electroencephalography (EEG) has vital and significant applications in different medical fields and is used for the primary evaluation of neurological disorders. Hence, having easy access to suitable and useful signal is very important. Artifacts are undesirable confusions which are generally originated from inevitable human activities such as heartbeat, blinking of eyes and facial ...