A detailed study of the magnetic resonance (MR) appearance of the cervical nerves and neural foramina is presented. Using a "butterfly" local coil and a 1.5-T GE Signa MR system, the authors obtained 3-mm-thick axial, parasagittal, and 45 degrees oblique MR images of the cervical neural foramina in four normal volunteers. For the oblique images, subjects were rotated 45 degrees toward the right...

Attenuation correction is necessary for quantification in micro-single-photon emission computed tomography (micro-SPECT). In general, this is done based on micro-computed tomographic (micro-CT) images. Derivation of the attenuation map from magnetic resonance (MR) images is difficult because bone and lung are invisible in conventional MR images and hence indistinguishable from air. An ultrashor...

BACKGROUND AND PURPOSE Sparganosis is a rare parasitic infection in humans by a larval cestode of the genus Spirometra. Preoperative diagnosis of cerebral sparganosis in the past has been very difficult. Our objective was to evaluate the CT and MR features of cerebral sparganosis in order to make a definite diagnosis. MATERIALS AND METHODS We retrospectively reviewed 25 patients (13 male and ...

Hajime Sakuma,' Kakuya Kitagawa,' Yasutaka Ichikawa,' Nanaka Ishida,' Kan Takeda,' Naoki Kato,' Satoshi Yoshise.* Mie University, 2-1 74 Edobashi, Tsu, Mie, Japan; 2Nihon Schering, 2-6-64 Nishimiyahara, Osaka, Japan Introduction: With recent advances in fast imaging techniques, contrast enhanced cardiac MR study can provide comprehensive assessments of myocardial perfusion, cardiac function and...

BACKGROUND AND PURPOSE MR imaging has played an increasingly important role in the diagnosis of Creutzfeldt-Jakob disease (CJD) since basal ganglia abnormalities on T2-weighted images have been described; thus, the aim of our study was to compare the value of different MR images in the diagnosis of CJD. METHODS One hundred fifty-seven patients with CJD underwent MR imaging examinations. Ninet...

The reconstruction of PET brain data in a PET/MR hybrid scanner is challenging in the absence of transmission sources, where MR images are used for MR-based attenuation correction (MR-AC). The main challenge of MR-AC is to separate bone and air, as neither have a signal in traditional MR images, and to assign the correct linear attenuation coefficient to bone. The ultra-short echo time (UTE) MR...

Spatially registered positron emission tomography (PET), computed tomography (CT), and magnetic resonance (MR) images of the same small animal offer potential advantages over PET alone: CT images should allow accurate, nearly noise-free correction of the PET image data for attenuation; the CT or MR images should permit more certain identification of structures evident in the PET images; and CT ...

BACKGROUND AND PURPOSE Our purpose was to investigate transient MR signal changes on periictal MR images of patients with generalized tonicoclonic seizure or status epilepticus and to evaluate the clinical significance of these findings for differential diagnosis and understanding of the pathophysiology of seizure-induced brain changes. METHODS Eight patients with MR images that were obtained...

background dynamic contrast-enhanced magnetic resonance imaging (dce - mri) has been widely used in the management of breast cancer, and its diagnostic value in breast imaging has been demonstrated. there have only been a few reports regarding the usefulness of pre-contrast imaging. knowledge about clinically significant findings of preoperative, pre-contrast t1 and t2 mr images will allow more...

mutual information (mi) is a widely used similarity metric for multimodality image registration. however, it involves an extremely high computational time especially when it is applied to volume images. moreover, its robustness is affected by existence of local maxima. the multi-resolution pyramid approaches have been proposed to speed up the registration process and increase the accuracy of th...