Intradural schwannomas of the spine: MR findings with emphasis on contrast-enhancement characteristics.

Intradural extramedullary schwannomas are nerve sheath neoplasms that consist of focal proliferations of Schwann cells involving a spinal nerve. We reviewed the MR findings in seven patients with pathologically proved intradural schwannomas. The contrast-enhancement characteristics on MR images were determined and compared with the histologic features of the tumor.

Role of magnetic resonance imaging in the evaluation of the hydroxyapatite orbital implant.

The role of magnetic resonance imaging (MRI) in the assessment of fibrovascular ingrowth in the integrated hydroxyapatite orbital implant is evaluated. Fifteen patients who underwent enucleation and placement of a hydroxyapatite orbital implant were evaluated for degree of implant vascularity with gadolinium-DPTA-enhanced MRI with surface coil before drilling the implant. On T1-weighted images, the hydroxyapatite sphere appeared with intermediate signal.

Prognostic significance of magnetic resonance imaging in the acute phase of cervical spine injury.

Fifty-seven patients with acute cervical spine injuries and associated major neurological deficit were examined within 2 weeks of injury by magnetic resonance (MR) imaging. All patients had abnormal scans, indicating intramedullary lesions. This study was undertaken to determine if the early MR imaging pattern had a prognostic relationship to the eventual neurological outcome.

Unusual dissection of the proximal vertebral artery: description of three cases.

We report three cases that reveal an array of etiologic and radiologic findings associated with dissection of the proximal segment of the vertebral arteries. Regardless of etiology, the proximal segment may be the principal site of dissection in these vessels.

Clinical safety and efficacy of gadoteridol: a study in 411 patients with suspected intracranial and spinal disease.

In this phase III study, 411 adult patients with suspected intracranial or spinal disease underwent magnetic resonance (MR) imaging before and after intravenous injection of 0.1 mmol/kg gadoteridol (gadolinium 1,4,7-tris [carboxymethyl]-10-[2'-hydroxypropyl]-1,4,7,10-tetraazacyclododecane+ ++). MR images were evaluated by a single unblinded reader at each of 27 sites; the diagnosis was confirmed with one of nine imaging or surgical procedures within 8 weeks before or after MR imaging.

Assessment of carotid artery patency on routine spin-echo MR imaging of the brain.

We retrospectively reviewed the routine spin-echo MR studies of the brain in 12 patients with 13 angiographically demonstrated occlusions and in 14 patients with 16 high-grade stenoses of the carotid arteries. Intraluminal signal that was isointense with adjacent brain on long TR/short TE and long TR/long TE images was 100% specific for atherosclerotic occlusion. Of the 13 proved occlusions, six (46%) had significant degrees of hyperintense intraluminal signal indistinguishable from that observed consequent to slow flow distal to high-grade stenoses.

Intervertebral disc injury complicating cervical spine trauma.

The incidence of acute herniated nucleus pulposus was determined in 55 patients with cervical spine trauma. A standardized protocol and a 1.5-T magnetic resonance image scanner was used to document a 42% incidence of acute herniated nucleus pulposus in patients studied within 72 hours of injury.

Enhanced resolution of pituitary fossa by three-dimensional fat-suppressed gradient-echo magnetic resonance: before and after gadolinium enhancement.

In imaging small anatomical parts such as the pituitary fossa, thin sections enhance the spatial resolution. Gradient recalled images (GRASS) using three-dimensional volume data produce ultrathin contiguous sections with a high signal-to-noise ratio. In this study, conventional spin-echo magnetic resonance images (MRIs) of the pituitary fossa were compared to three-dimensional gradient recalled MRI in 5 volunteers and 10 patients suspected of having pituitary gland abnormalities.

Diagnostic capabilities of magnetic resonance imaging and computed tomography in acute cervical spinal column injury.

The present study was conducted to evaluate the imaging capabilities of magnetic resonance imaging (MRI) in evaluating acute cervical spinal column injury and compare these results to that of computed tomographic (CT) imaging. Forty-nine patients undergoing MRI at a Level I and regional spinal cord trauma center to evaluate cervical spinal column injury were studied. Seventy-one injuries were identified by MRI.

Magnetic resonance imaging of acute cervical spine trauma. Correlation with severity of neurologic injury.

Prior to the advent of computer-assisted imaging techniques, conventional radiographic studies did not accurately depict the severity of soft tissue injury (spinal cord and paravertebral tissue) attending severe spinal trauma. Computed tomography scanning is clearly superior to plain radiography in the demonstration of osseous fractures and impactions, but this modality does not clearly depict ligamentous or disc injuries and does not image the spinal cord directly. The authors' preliminary experience indicates that magnetic resonance imaging (MRI) more accurately defines the extent of soft tissue damage in the zone of injury.

Paranasal sinus mucocele: unusual MR manifestations at 1.5 T.

The classic MR appearance of paranasal sinus mucoceles is due to its cystic composition. We present two cases of paranasal sinus mucocele that exhibit atypical signal characteristics. The morphology of this lesion, rather than its signal intensity, is paramount in establishing this diagnosis.

CT characteristics of orbital pseudotumors and other orbital inflammatory processes.

Orbital pseudotumor is a nonspecific inflammatory process of unknown etiology that may mimic a true orbital neoplasm, specifically lymphoma. It exhibits a highly variable clinical and radiographic presentation. Thirty-nine patients with a presumptive diagnosis of orbital inflammatory disease were examined with CT and evaluated with respect to 13 findings associated with inflammatory disease of the orbit.

Retinoblastoma and simulating lesions: role of CT and MR imaging.

Diagnosis of retinoblastoma is one of the most challenging problems of pediatric ophthalmology and radiology. It must be differentiated from numerous simulating lesions. Accurate diagnosis by means of ultrasonography, CT, and MR is essential for prompt treatment and prevention of metastasis.

Orbital lymphoma. Role of CT and MRI.

CT and MRI have made it possible to make a strongly presumptive diagnosis of orbital lymphoid tumors. Orbital lymphomas are usually homogeneous masses of relatively high density and sharp margins. The lesions mold themselves to pre-existing structures without eroding the bone.

Microspectrophotometric studies of Romanowsky stained blood cells. IV. Maturation of myeloid and erythroid cell lines in bone marrow.

A quantitative characterization has been made of azure B/eosin stained cells from bone marrow. Two cell lines were followed: the myeloid line (white cell blast, promyelocyte, neutrophilic myelocyte, neutrophilic metamyelocyte, neutrophilic band, neutrophilic segmented) and the erythroid line (rubriblast, prorubricyte, rubricyte, metarubricyte, diffusely basophilic erythrocyte, erythrocyte). A consensus scheme was used to obtain the "true" classification of the cells.