Familial hypophosphatemic rickets causing ocular calcification and optic canal narrowing.

In a case of familial hypophosphatemic rickets, marked bone thickening caused narrowing of the optic canals, resulting in bilateral optic atrophy. The case also showed metastatic calcification in the walls of both globes.

Meningeal myelomatosis: CT and MR appearances.

Meningeal myelomatosis is a rare feature of multiple myeloma. We report a case of IgG-kappa myeloma presenting as bilateral intracranial extraaxial masses.

Central nervous system cryptococcosis: parenchymal calcification and large gelatinous pseudocysts.

In an 11-year-old immunocompetent girl with protracted cryptococcal infection of the central nervous system, CT showed multiple areas of parenchymal calcification. MR imaging showed large gelatinous pseudocysts around the brain stem. These imaging features and the child's age are unusual for intracranial cryptococcosis.

Engorged anterior epidural venous plexus mimics an anterior epidural mass.

A 48-year-old woman presented with severe neck pain on flexion 1 week after a reportedly uncomplicated lumbar puncture, and with a slightly elevated white blood cell count. Magnetic resonance imaging showed an anterior epidural mass that was thought to represent an epidural abscess. At surgery, the epidural "mass" was due to an engorged anterior epidural venous plexus.

Neurosarcoidosis resembling meningioma: MRI characteristics and pathologic correlation.

A 37-year-old woman had visual changes. Magnetic resonance imaging showed an extraaxial mass in the anterior clinoid region that was presumed to be meningioma. There was no evidence of systemic or leptomeningeal disease. Pathologic findings were consistent with sarcoidosis. Isolated mass-like neurosarcoidosis, without systemic or leptomeningeal disease is difficult to diagnose preoperatively.

The spectrum of neuroimaging abnormalities in solvent abuse and their clinical correlation.

The brain magnetic resonance (MR) images and medical records of 6 patients with a history of chronic toluene abuse were reviewed retrospectively. The imaging findings were correlated with clinical impairment. The major findings consisted of atrophy (6 patients), white matter T2 hyperintensity (6 patients), and T2 hypointensity involving the basal ganglia and thalami (5 patients). Also seen was focal enhancement, previously unreported for patients who abused toluene. This study showed a correlation between the degree of neurological impairment and extent of white matter disease. There was no correlation between the severity of white matter changes on MR images and the presence of T2 hypointensity or duration of toluene abuse. There was no definite clinical evidence of damage to the basal ganglia and thalami despite the MR imaging finding of T2 hypointensity. Temporal evidence against the theory that toluene accumulation causes the T2 hypointensity was found.

Sarcoid myelopathy.

A 45-year-old woman with history of iritis, uveitis, and sarcoidosis of the skin presented with a subacute cervical myelopathy. Magnetic resonance imaging (MRI) showed patchy, multifocal, gadolinium-enhancing intramedullary lesions of the spinal cord, and extramedullary lesions of the basal cisterns and fourth ventricle. Symptoms and MRI abnormalities were improved within 1 month of corticosteroid therapy.

Solitary plasmacytoma of the mastoid bone presenting as coalescent mastoiditis.

Acute mastoiditis is a complication of acute otitis media that produces air cell opacification and coalescence on computed tomographic (CT) imaging. This appearance, however, is nonspecific and may be seen in patients with infection and tumor. Magnetic resonance imaging (MRI) can aid in differentiating the two on the basis of differences in tissue signal characteristics and by showing the presence or absence of an associated soft-tissue mass. In this report, we demonstrate the utility of MRI as a complementary imaging modality to CT in the diagnosis of a solitary plasmacytoma of the temporal bone that was initially thought to be coalescent mastoiditis.

Hypoxic-ischemic encephalopathy in areas of primary myelination: a neuroimaging and PET study.

The stage of regional structural and biochemical development of the central nervous system appears as a critical factor determining the distribution of hypoxic-ischemic lesions during the perinatal period. We describe the brain lesions in 12 patients who suffered hypoxia-ischemia during the perinatal period. The gestational age ranged from 35 to 42 weeks and the age at death from 2 to 16 weeks. There is one patient alive at age 18 years and a second patient at age 1 year. The cerebral cortical damage is mainly restricted to areas of primary myelination and adjacent subcortical white matter. In addition, there is thalamic, basal ganglia, brainstem, and spinal cord damage. It is postulated that selective damage occurs in those areas which at the moment of the hypoxic-ischemic insult had achieved higher rates of oxygen-glucose utilization. This hypothesis is supported by studies utilizing positron emission tomography which indicates that glucose utilization in the normal human neonatal brain follows a phylogenetic order. Regions that achieved higher levels of glucose consumption are those that suffered the brunt of the damage in our term neonates.

Clinical and surgical application of reformatted high-resolution CT of the temporal bone.

High resolution CT has played a pivotal role in temporal bone imaging since the early 1980s. Although the appearance of MR imaging technology with its superior demonstration of fluid-containing spaces of the inner ear and the posterior fossa structures, CT continues to offer distinct advantages for the evaluation of conductive hearing loss, and petrous apex lesions. With the advent of helical scanning techniques, CT is increasingly the imaging study of choice for definitive preoperative temporal bone imaging.

FLAIR and HASTE imaging in neurologic diseases.

The need to develop faster imaging techniques has led to the implementation of fast spin-echo imaging, EPI, and hybrid imaging techniques. This article discusses two of these faster imaging techniques, fast fluid-attenuated inversion-recovery (FLAIR) imaging and half-Fourier acquisition single-shot turbo spin-echo (HASTE) imaging, and their potential clinical application in neurologic diseases. FLAIR imaging, in particular, has demonstrated considerable promise for the evaluation of intracranial pathology. HASTE imaging can be used for rapid imaging of the brain or spine in those patients who are claustrophobic or who have difficulty remaining still, but it does not yet have a primary role in clinical neuroradiology.

Increased intracranial pressure and the cerebrospinal fluid spaces.

Increased intracranial pressure is a frequent accompaniment to many of the disease processes affecting the brain and its coverings. Such increased pressure is associated with significant morbidity and mortality. This article briefly reviews the pathophysiology of increased intracranial pressure and addresses the clinical and neuroradiological presentation of increased pressure. As part of the discussion, the concept of hydrocephalus and its treatment and complications are addressed.

Neuroradiologic review of intracranial infection.

The detection of intracranial infection continues to be a common reason for neuroradiologic examination. This review covers the neuroradiologic findings of the variety of common infections. It includes meningitis and its complications, as well as bacterial, viral, tuberculous, fungal, and parasitic diseases. Finally, a review of the common infections associated with AIDS is presented. With an increased ability to recognize such infections, radiologists should be able to supply their clinical colleagues with more specific diagnoses.

CT-Guided Percutaneous Fine-Needle Aspiration Biopsy of Posterior Skull Base Lesions.

We describe a retroauricular approach, adjacent to the mastoid tip, in two patients that allowed successful biopsy of posterior skull base lesions. Diagnoses were central giant cell granuloma, an unusual tumor rarely reported in the skull base, and meningioma. In both patients, the needle biopsy accurately identified the pathology found at surgery. The described approach may allow biopsy of posterior lesions that are inaccessible with other methods.

Topical contrast-enhanced CT and MR dacryocystography: imaging the lacrimal drainage apparatus of healthy volunteers.

OBJECTIVE: The purpose of this study was to evaluate the feasibility of administering topical contrast material during helical CT dacryocystography and topical saline solution during MR dacryocystography to reveal the lacrimal drainage apparatus. SUBJECTS AND METHODS: Fourteen healthy volunteers underwent helical CT dacryocystography, MR dacryocystography, or both. Eight of the 14 subjects underwent both techniques; three subjects underwent MR dacryocystography, and three subjects underwent CT dacryocystography. Images were evaluated by two radiologists for degree of visualization of components of the lacrimal drainage apparatus. Each volunteer was questioned about the relative discomfort of contrast material and saline solution administration. RESULTS: The lacrimal drainage system was seen on both CT dacryocystography and MR dacryocystography. CT dacryocystography allowed two-dimensional and three-dimensional reconstructions on which adjacent bone anatomy could be seen. The MR dacryocystography two-dimensional reconstructions and maximum intensity projections also showed the drainage apparatus. However, smaller drainage structures were more consistently seen on CT dacryocystography than on MR dacryocystography. Saline solution was more comfortable than contrast material. CONCLUSION: CT dacryocystography and MR dacryocystography reproducibly and non-invasively revealed the lacrimal drainage apparatus and allowed a better physiologic examination than cannulation dacryocystography. MR dacryocystography can be performed without administration of ionizing radiation or contrast material, but this technique cannot show adjacent bone anatomy and less consistently showed the smaller drainage structures than CT dacryocystography.

Malignant fibrous histiocytoma in a 9-year-old girl.

A case of malignant fibrous histiocytoma in the left temporoparietal region of a 9-year-old girl is reported. The tumor was cystic with a mural nodule. Microscopically, the tumor focally infiltrated the leptomeninges sparing the dura mater, and was composed of glial fibrillary acidic protein-negative cells suspended in a rich meshwork of reticulin fibers. Electron microscopy showed the presence of extensive thin processes on the cell's surface and lysosomal-like inclusions in the cytoplasm. No basal lamina was present around the cells. The clinical and pathologic features of this case were compared with those of previous cases described in the world literature.