Intraplaque dissection of the basilar artery.
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Biomedical subjects
Publications and source records attributed to C Douglas Phillips.
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OBJECTIVE: The purpose of our study was to quantitatively evaluate calcified atherosclerotic burden in the cervical carotid arteries using MDCT to determine the relationship of scores with luminal stenosis and symptomatology. MATERIALS AND METHODS: Calcium plaque volume was measured in 106 cervical carotid arteries (53 patients) using MDCT angiography. The study group included 32 asymptomatic patients (mean age, 70.2 +/- 8.7 [SD] years; 15 women, 17 men) and 21 patients with ischemic neurologic symptoms (69.6 +/- 12.9 years; eight women, 13 men). By vessel, there were 43 high-grade stenotic (> or = 60% by North American Symptomatic Carotid Endarterectomy Trial [NASCET] criteria), 15 moderate-grade stenotic (30-59%), and 44 mild-grade stenotic or normal (0-29%) vessels, with four excluded for prior carotid endarterectomy. Volume scores were calculated by summing the area of calcium in the common and extracranial internal carotid arteries on axial slices and multiplying by the slice increment. RESULTS: Controlling for cardiovascular risk factors and luminal stenosis, we found that scores were significantly related to the occurrence of symptoms (p = 0.003). Even with patient age as a covariant, patients with high-grade stenosis had significantly higher scores than those without high-grade disease (p = 0.004). Moreover, quantitative burden was associated with luminal stenosis on adjusted multivariate analysis (p = 0.034). The specificity and positive predictive value for high-grade luminal narrowing were notably lower on individual vessel analysis than on total score analysis, likely secondary to variability in vascular remodeling. CONCLUSION: Calcium scores in the cervical carotid arteries may represent an independent marker for luminal stenosis and ischemic symptoms. A prospective longitudinal study examining calcium levels and morbidity may be warranted to examine whether burden has a role in risk stratification.
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BACKGROUND: Aspirin-exacerbated respiratory disease (AERD) is a disease of intense eosinophilic inflammation that can produce fibrosis, hyperplasia, and remodeling. OBJECTIVE: To investigate the usefulness of quantifying severity of chronic hyperplastic eosinophilic sinusitis in predicting the presence of AERD. METHODS: Data were compared between asthmatic patients who reported exacerbations after aspirin ingestion and those who did not. The primary outcome measure was severity of sinusitis using a validated computed tomography (CT) scan-based scoring system. Indices of lower airway remodeling and other markers of inflammation were also evaluated. RESULTS: Twenty-one patients with AERD were compared with 19 patients with aspirin-tolerant asthma (ATA). Patients were well matched for asthma severity as shown by their similar lung function as measured by postbronchodilator forced expiratory volume in 1 second. Patients with AERD were distinguished by their sinus CT scores (AERD patients: 16.9; 95% confidence interval [CI], 13.4-21.3; ATA patients: 6.2; 95% CI, 4.2-9.1; P < .001), and they were considerably more likely to have nasal polyps (AERD patients: 90%; ATA patients: 26%; P < .001). In addition, AERD patients demonstrated increased total lung capacity (AERD patients: 107.9%; 95% CI, 99.9%-117.6%; ATA patients: 98.0%; 95% CI, 93.7%-102.5%; P = .05), reflecting a trend toward increased air trapping. No significant differences occurred in diffusing capacity, exhaled nitric oxide, eosinophilia, or exhaled breath condensate pH. CONCLUSIONS: AERD can be distinguished from ATA by the extent of hyperplasia on CT scan and the presence of nasal polyps. We hypothesize that AERD represents a remodeling process that affects both the upper and lower airways.
OBJECTIVE: Risk assessment based on plaque vulnerability would be valuable in the management of asymptomatic carotid stenosis. The purpose of this study was to compare plaque morphology in symptomatic and asymptomatic patients with significant extracranial carotid artery stenosis using MDCT angiography. MATERIALS AND METHODS: We identified 31 patients with greater than 60% carotid artery stenosis on MDCT angiography using the criteria of the North American Symptomatic Carotid Endarterectomy Trial Collaborators. We analyzed plaque density by blinded review in Hounsfield units in the atherosclerotic plaques of 15 symptomatic and 21 asymptomatic stenotic vessels for classification as soft, intermediate, or calcified. Data were analyzed using multiple logistic regression. RESULTS: Even with age, traditional cardiovascular risk factors, and treatment taken into account, we found that calcified plaques were 21 times less likely to be symptomatic than noncalcified plaques (95% confidence interval for odds ratio, 0.003, 0.749; p = 0.030). No significant predictive value was found between soft (p = 0.23) or intermediate (p = 0.18) plaque morphology for the occurrence of symptoms. CONCLUSION: MDCT angiography may help risk-stratify patients with asymptomatic carotid artery stenosis. Extracranial carotid artery calcified plaques causing stenosis are significantly less likely to be symptomatic and thus may be more stable than noncalcified plaques. This finding may have implications for the interpretation of calcification of atherosclerotic plaque in other vascular beds.
Benign triton tumors (neuromuscular hamartomas) are rare neoplasms composed of well-differentiated striated muscle fibers admixed with peripheral nerve fibers. To the best of our knowledge, this is the third case reported in the world literature of a benign triton tumor involving cranial nerve V (trigeminal nerve) and the first in the radiology literature. The previous reports of this lesion have focused on its unusual pathology and not on the imaging findings. In light of the imaging appearance of this lesion, we consider that the imaging findings may suggest this uncommon diagnosis.
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We report a case of a thoracic intradural extramedullary capillary hemangioma. The MR imaging appearance was nonspecific for this lesion, and it could not be distinguished from more common spinal intradural extramedullary lesions. The presence of subtly enlarged abnormal vessels on contrast MR images should, however, lead one to consider a vascular mass and order preoperative spinal arteriography.
We describe a rare case of progressive osseous heteroplasia of the face in a child. Biopsy showed osteoma cutis superficially with ectopic bone formation in the deeper tissues including skeletal muscle. Analysis of DNA from peripheral blood leukocytes showed mutations in the gene encoding the alpha subunit of the stimulatory G protein of adenylyl cyclase (GNAS1), confirming the diagnosis of progressive osseous heteroplasia.
BACKGROUND: The inappropriate closure of the vocal cords is characteristic of vocal cord dysfunction (VCD). These patients present with wheezing and frequently receive a misdiagnosis of asthma. OBJECTIVE: To demonstrate the ability of computed tomography (CT) scored for the presence and extent of sinus disease and markers of inflammation to distinguish patients with VCD from patients with asthma. METHODS: Comparisons of 13 patients with VCD were made to 77 patients presenting to the emergency room with acute asthma, 31 non-acute asthmatic patients, and 65 nonasthmatic controls. Evaluation consisted of exhaled nitric oxide gas (eNO), circulating eosinophils, and total serum immunoglobulin (Ig)E, as well as the sinus CT scan. RESULTS: Extensive sinus CT changes were present in 23 of 74 acute asthmatic patients, 5 of 29 non-acute asthmatic patients, and 2 of 59 nonasthmatic controls. In addition, absolute eosinophil counts, eNO, and total IgE were significantly elevated among the asthmatic patients. Sinus symptoms reported by questionnaire did not predict sinus CT findings. Among the patients with VCD, none had extensive sinus disease. They also had normal eNO, low IgE, and normal eosinophil count. Five of the patients presenting to the emergency room who were identified as acute asthmatic were identified with VCD by laryngoscopy and were all characterized by the absence of significant inflammation on their sinus CT scan, low IgE, and normal eosinophil count. CONCLUSIONS: Among patients presenting with intermittent or reversible airway obstruction, patients with VCD can be distinguished from asthma by minimum or absence of inflammation in their sinuses as shown by CT scan. Clinical symptom scores are not predictive of presence or extent of sinus disease in most cases.
OBJECTIVE: To determine the utility of performing three-dimensional (3D) computed tomography (CT) of congenital naso-frontal anomalies for preoperative planning and counseling and compare it with standard two-dimensional (2D) imaging and intraoperative findings. STUDY DESIGN: Prospective case evaluation of imaging studies and medical records in cohort of patients with congenital nasal anomalies. METHODS: We performed 3D CT imaging of three different types of congenital nasal lesions. Additional preoperative imaging consisted of standard 2D CT scans and/or magnetic resonance imaging (MRI). Information obtained from the 3D CTs was compared with other standard imaging and intraoperative findings. RESULTS: 3D CT was most useful in the case of a large encephalocele with a significant bony defect of the anterior cranial fossa. It provided moderate utility when used to evaluate a nasal dermoid with nasal bone and septal abnormalities and was of limited benefit in the case of a bifid nose with significant external soft tissue deformity and relatively normal bony anatomy. CONCLUSION: Congenital midline nasal anomalies are rare lesions with the potential for intracranial extension and anterior skull base abnormalities. The safe surgical treatment of these lesions depends upon accurate preoperative imaging to assist in establishing the diagnosis, to help guide surgical planning, and to assist in communicating the diagnosis and surgical approach for optimal counseling of families. 3D CT was instrumental in providing additional useful information in cases with significant bony abnormalities at little additional cost or time. It is also beneficial for preoperative counseling of patients and families with limited medical knowledge.
CTA and MRA techniques likely will continue to increase in use in the evaluation of the extracranial cerebrovascular system. The increasing reliance on noninvasive tests mirrors an overall concern with the risks and costs of more invasive examinations. Given the rapid development of the computer technology, data acquisition, and reconstruction algorithms in the past few years, it is apparent that CTA and MRA also will continue to improve.
The seventh cranial nerve is responsible for much of what makes us individual--the facial expression worn by each individual. The facial nerve (CN VII) is commonly divided into 4 segments for examination: the nucleus and tracts, the cistemal segment that traverses the internal auditory canal, the intratemporal segment (through the bony facial nerve canal), and the peripheral segment. Immediately on leaving the temporal bone at the stylomastoid foramen, the peripheral segment of CN VII becomes much more complicated to follow and is essentially invisible to imaging. Each segment of the facial nerve may be involved by differing pathology. In this report we break down the facial nerve into more easily understood divisions and cover the common pathology of each of these segments.
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Digital subtraction myelography is described for its utility in the detection of dural leaks associated with pseudomeningoceles. Although myelography, CT, and MR imaging have been described as effective means for diagnosing pseudomeningocele, this complicated entity can be difficult to diagnose.