BACKGROUND AND PURPOSE Experimental studies have shown that solutes diffuse more slowly into degenerated intervertebral disks than into normal disks. A noninvasive clinical study of diffusion in intervertebral disks is not generally available. Our purpose was to evaluate contrast-enhanced MR images to study diffusion in normal and degenerated lumbar intervertebral disks. METHODS The change in...

Most functional magnetic resonance imaging (fMRI) studies in animals are conducted under anesthesia to minimize motion artifacts. However, methods and techniques have been developed recently for imaging fully conscious rats. Functional MRI studies on conscious animals report enhanced BOLD signal changes as compared to the anesthetized condition. In this study, rats were exposed to different con...

PURPOSE To evaluate the MR appearance of normal and pathologic states of the submandibular gland. METHODS MR images of 22 healthy subjects and 21 patients with histopathologically confirmed disorders of the submandibular gland (five pleomorphic adenomas, two hemangiomas, two malignant lymphomas, one adenoid cystic carcinoma, one squamous cell carcinoma, and 10 cases of sialadenitis) were revi...

The high-intensity signal seen on MR images of the posterior pituitary has been the subject of numerous reports, including an important one in this issue of AJNR [1]. In 1984, we studied anatomic sections of the sella. A curvilinear pad of fat in the posterolateral recesses of the sella corresponded in location to the high-intensity signal on MR images [2] . Subsequent observations on the failu...

PURPOSE Using MR imaging, we assessed the signal, size, and enhancing characteristics of the cervical cord in patients in whom radiation myelopathy developed after radiotherapy for nasopharyngeal carcinoma. PATIENTS AND METHODS Ten patients, 3 men and 7 women, aged from 32 to 77 years, were included. MR imaging was performed 1 to 53 months after clinical manifestations of myelopathy. RESULT...

OBJECTIVE We wanted to assess the MR imaging findings of ovarian cystadenofibroma and cystadenocarcinofibroma, and we wanted to find clues for making the differential diagnosis between them. MATERIALS AND METHODS The MR images of 12 pathologically proven cystadenofibromas and two cystadenocarcinofibromas were reviewed, with a focus on the internal architecture, signal intensity and enhancemen...

BACKGROUND AND PURPOSE Lumbar pedicle marrow hyperintense signal on T2- and STIR-weighted images is not an uncommon finding. We hypothesize that these marrow signal intensity changes and their behavior within the pedicle are associated with clinical symptoms and that their improvement or resolution correlates with clinical improvement. We investigated the prevalence of these pedicle marrow chan...

OBJECTIVE The purpose of this study was to determine whether MR imaging features can reliably distinguish hemangiomas from malignant soft-tissue masses. MATERIALS AND METHODS We retrospectively reviewed MR imaging studies of 22 patients with soft-tissue hemangiomas and 22 patients with malignant soft-tissue masses. Images were reviewed and agreement reached by a consensus interpretation of tw...

Focal signal intensity loss of the basilar artery on MR angiograms obtained in a 69-year-old man was considered to be caused by an embolus, and thrombolytic therapy was initiated. On the follow-up MR angiograms, the same oval signal intensity loss of the basilar artery was observed. On the basis of a virtual endoscopic look into the basilar artery, the diagnosis of a rare vascular anomaly--a fe...

MR findings of a patient with hemolytic uremic syndrome involving the CNS are described. Abnormal high signal intensity on T2-weighted images combined with swelling in the lentiform nucleus, posterior limb of internal capsule, external capsule bilaterally, and left extreme capsule was shown on initial MR; a small low signal intensity in the left putamen on T1- and T2-weighted images and general...