Hematogenous pyogenic facet joint infection.

STUDY DESIGN: Retrospective. OBJECTIVES: To determine the incidence, clinical presentation, diagnostic laboratory values, imaging characteristics, and optimal treatment of hematogenous pyogenic facet joint infections. SUMMARY OF BACKGROUND DATA: There are 27 documented cases of hematogenous pyogenic facet joint infections. Data regarding incidence, clinical presentation, diagnosis, and treatment response are incomplete because of the paucity of reported cases. METHODS: This is a retrospective study of all cases of hematogenous pyogenic facet joint infection treated at one institution. Data from previous publications were combined with the present series to identify pertinent clinical characteristics and response to treatment. RESULTS: A total of six cases (4%) of hematogenous pyogenic facet joint infection were identified of 140 cases of hematogenous pyogenic spinal infection at our institution. Combining all reported cases reveals the following: The average patient age is 55 years. Ninety-seven percent of cases occur in the lumbar spine. Epidural abscess formation complicates 25% of the cases of which 38% develop severe neurologic deficit. Erythrocyte sedimentation rate and C-reactive protein are elevated in all cases. Staphylococcus aureus is the most common infecting organism. Magnetic resonance imaging is accurate in identifying the septic joint and associated abscess formation. Percutaneous drainage of the involved joint has a higher rate of success (85%) than treatment with antibiotics alone (71%), but the difference is not significant (P = 0.37). CONCLUSIONS: Hematogenous pyogenic facet joint infection is a rare but underdiagnosed clinical entity. Facet joint infections may be complicated by abscess formation in the epidural space or in the paraspinal muscles. Uncomplicated cases treated with percutaneous drainage and antibiotics may fare better than those treated with antibiotics alone. Cases complicated by an epidural abscess and severe neurologic deficit should undergo immediate decompressive laminectomy.

Neuroimaging of the aging brain.

Age-related white matter injury has been recognized increasingly with the improvement of brain imaging technology. Arteriosclerosis and venous collagenosis, which occur with aging, result in a spectrum of white matter changes that range from periventricular to subcortical and deep white matter hyperintensities best seen on T2 weighted magnetic resonance imaging. These white matter changes are associated not only with aging, but with hypertension and silent infarctions. Loss of brain volume and accumulation of iron in putamen occur with normal, healthy aging. This article discusses the imaging appearance of healthy aging and pathological correlates of similar appearing alterations. The imaging findings of the most common neurodegenerative disorders, Alzheimer's and Parkinson's disease, are highlighted.

Pseudoprogression of cerebral cavernous angiomas: the importance of proper magnetic resonance imaging technique.

Magnetic resonance imaging (MRI) is the method of choice to detect cerebral cavernous angiomas. Specifically tailored MRI studies are necessary to evaluate patients with cerebral cavernous angiomas. The patient described here, for whom serial MRIs performed on different scanners falsely suggested rapid disease progression, illustrates the point.

Parietal occipital edema in hypertensive encephalopathy: a pathogenic mechanism.

Eight patients with hypertensive encephalopathy from diverse etiologies developed cerebral edema in the vertebrobasilar distribution which resolved after blood pressure was lowered. Parietal occipital edema is a recognized feature of hypertensive encephalopathy. The explanation for this regional pathological variation in hypertensive encephalopathy remains undefined. Some evidence suggests that sympathetic innervation of the anterior cerebral vasculature may be protective, and conversely, the relative lack of sympathetic innervation in the vertebrobasilar vasculature may predispose the parietal occipital region to the development of cerebral edema in hypertensive encephalopathy.

Infantile-onset spinocerebellar ataxia: MR and CT findings.

PURPOSE: To report the MR and CT findings in a hereditary disease, infantile-onset spinocerebellar ataxia (IOSCA). METHODS: We studied the brains of 17 patients with infantile-onset spinocerebellar ataxia with CT and/or MR to determine the presence of cerebellar and brain stem atrophy and parenchymal lesions. RESULTS: Cerebellar cortical atrophy was seen in 13 patients. The degree of atrophy correlated with increasing age and clinical deterioration. Brain stem atrophy was seen in 8 patients. It was never severe, and the basis pontis was not flattened even in the most severe cases. Hyperintense lesions were noted within the white matter of cerebellum, in the dentate nuclei, and in the middle cerebellar peduncles in 3 patients. The upper cervical cord was seen in 9 patients and showed mild to moderate atrophy in 4. The basal ganglia and cerebral hemispheres were normal, except in 2 patients transient cortical and subcortical lesions developed during episodes of status epilepticus; mild cortical brain atrophy subsequently developed. CONCLUSION: The brain MR and CT findings of patients with infantile-onset spinocerebellar ataxia correspond to the neuropathologic entities of cerebellar cortical atrophy, olivopontocerebellar atrophy, and spinocerebellar atrophy. The appearance of the findings followed a uniform time sequence from cerebellar cortical atrophy in the early stage of the disease to olivopontocerebellar atrophy and spinocerebellar atrophy in the later stage. The severity of atrophy correlated with clinical deterioration.

Duplication of the extracranial internal carotid artery.

We describe a case of duplication of the left internal carotid artery from a point 1 cm distal to the origin to the proximal petrous segment where the vessel reunites. Duplication and fenestration of the internal carotid artery are discussed. A review of embryologic development is presented. Identification of these entities is important, especially in patients who require surgical intervention involving the internal carotid artery.

Acute and delayed cerebral infarction after wasp sting anaphylaxis.

A 52-year-old man developed a severe anaphylactic reaction after a wasp sting. Slurred speech and left hemiparesis were noted a few hours later. Three-and-one-half weeks later, he became acutely obtunded and quadriparetic. Angiographic studies demonstrated complete and near-complete occlusions of the right and left internal carotid arteries, respectively. A mechanism is suggested for delayed ischemic stroke after wasp sting anaphylaxis that involves cerebrovascular sympathetic innervation.

Wasp sting-associated cerebral infarction: a role for cerebrovascular sympathetic innervation.

A 38-year-old man, stung repeatedly by wasps on the left face and neck, had his left internal carotid artery occluded 2 days later. A mechanism for ischemic stroke involving the sympathetic innervation of cerebral vasculature is suggested.

Serial MRI and CT findings in infantile Krabbe disease.

Krabbe disease (globoid cell leukodystrophy) is an autosomal recessive childhood disorder characterized by severe motor and mental deterioration. The disease has been divided into 3 main types and further subdivided into several subtypes based on age of onset and symptoms. Initial clinical findings and magnetic resonance imaging (MRI) with several follow-up scans are presented to identify the order and extent of white matter involvement and developing brain atrophy in a child with the floppy infant variant of Krabbe disease. When the patient's clinical condition proceeded to stage 2, MRI disclosed severe involvement of the deep white matter around the atria and posterior limbs of the internal capsules. At the same time there was progression of normal myelination around the frontal horns. At age 32 months, the patient's clinical condition proceeded to stage 3; she did not interact with her environment. MRI revealed a significant decrease of white matter volume, generalized atrophy, and abnormal high signal in all white matter areas except the anterior limbs of the internal capsules. At the same time the volume of the central gray nuclei was decreased and also demonstrated abnormal high signal. Despite its sensitivity, MRI could not differentiate the findings of this variant of Krabbe disease from the classic form; therefore, subclassifications of Krabbe disease should be made on clinical grounds because they cannot be distinguished by biochemical or radiologic (MRI) criteria.

The initial impact of computed tomography on mortality attributed to brain tumor.

The exponential growth in the number of computed tomography scanners in the United States between 1975 and 1977 was associated with a transient increase (11.9 and 14.4% for men and women, respectively) in annual crude mortality rates for primary malignant brain tumor from 1976 through 1978. This transient increase in mortality appears to have been an artifactual epiphenomenon associated with the introduction of a new technology.

Multiple sclerosis masquerading as a mass lesion.

Six patients presenting with new neurological deficits underwent magnetic resonance imaging (MRI) that displayed mass lesions leading to diagnoses of tumor or abscess. Biopsy revealed demyelinating lesions.

Clinical evaluation of stenosis of the carotid bifurcation with magnetic resonance angiographic techniques.

We evaluated the images of 60 carotid artery bifurcations in 31 patients suspected to have carotid artery disease who underwent invasive carotid angiography and combined two-dimensional, phase-sensitive and a gradient-echo magnetic resonance angiography. The phase scans consisted of seven serial projections that were obtained at 20 degrees intervals (11.0 minutes) around the carotid bifurcation; the gradient-echo (GRASS) scans were composed of 11 axial images (2.4 minutes) acquired through the bifurcation. The two magnetic resonance angiographic techniques yielded complementary pieces of information and were used together to compare magnetic resonance angiography with invasive angiography. Comparison of magnetic resonance and invasive angiograms of the 60 carotid arteries shows that the sensitivity (86%) and specificity (92%) of the magnetic resonance angiographic techniques we used to diagnose clinically significant carotid stenosis approach but do not reach those of invasive angiography.