AJR. American journal of roentgenology
-
AJR Am J Roentgenol · Nov 1994
Comparative Study Clinical Trial Controlled Clinical TrialProspective evaluation of extracranial carotid stenosis: MR angiography with maximum-intensity projections and multiplanar reformation compared with conventional angiography.
The purpose of this prospective study was to compare MR angiography of the carotid artery from the aortic arch through the circle of Willis using maximum-intensity projection (MIP) and multiplanar reformation (MPR) images with intraarterial angiography in the depiction of extracranial carotid atherosclerosis. ⋯ It is possible to image the entire carotid artery from the aortic arch through the circle of Willis with MR angiography in a clinically acceptable time. MPR of the 3D TOF MR angiogram reliably shows the percentage of carotid stenosis with no statistically significant difference compared with intraarterial angiography. The role of MR angiography in showing lesions in the circle of Willis or the aortic arch is promising, but the limited number of tandem lesions in this study makes it difficult to draw any conclusions.
-
Nosocomial (i.e., originating or taking place in a hospital) pneumonia is the leading cause of death from acquired nosocomial infections. The estimated prevalence of nosocomial pneumonia in intensive care units ranges from 10% to 65%, with fatality rates of 13-55%. ⋯ Recent investigations have provided new insights into the pathogenesis of VAP, and improved techniques have been developed for its diagnosis. Most important, emerging clinical data now suggest that new management strategies for VAP, including more specific indications for antimicrobial use, may significantly improve patients' outcomes.
-
AJR Am J Roentgenol · Nov 1994
Rotational injury of cervical facets: CT analysis of fracture patterns with implications for management and neurologic outcome.
Imaging studies of patients with rotational facet injuries of the cervical spine were retrospectively reviewed to determine the prevalence and pattern of associated fractures, to correlate injury pattern with recommended surgical stabilization, and to assess neurologic outcome. ⋯ Cervical rotational facet injuries are often accompanied by facet fractures and bilateral damage of the rotated vertebra. These injuries contribute to rotational instability and require specific internal fixation based on a precise delineation of all injuries. Facet dislocations without fractures have a significantly higher association with cord syndromes than do rotational facet injuries with fractures. CT, particularly with parasagittal reformations, is valuable in identifying all injuries of the rotated and subjacent vertebrae.
-
AJR Am J Roentgenol · Oct 1994
Comparative StudyFat-suppressed spoiled GRASS imaging of knee hyaline cartilage: technique optimization and comparison with conventional MR imaging.
We studied healthy volunteers with fat-suppressed three-dimensional (3D) spoiled gradient-recalled acquisition in the steady state (SPGR) to determine parameters that maximize positive contrast between knee articular cartilage and fluid, marrow fat, and muscle; and we compared the technique with conventional MR imaging sequences. The purpose was to determine if fat-suppressed 3D SPGR imaging is useful for detecting abnormalities of the articular cartilages. ⋯ When a fat-suppressed 3D SPGR sequence of 60/5/40 degrees (TR/TE/flip angle) is used, MR images can show high positive contrast between articular hyaline cartilage and adjacent structures. This convenient technique is different from standard MR imaging sequences because it demonstrates greater signal intensity in cartilage than in fluid, marrow fat, and muscle, and because it consistently shows an organized internal architecture of hyaline cartilage. Fat-suppressed 3D SPGR imaging therefore has promise for detecting abnormalities of the articular cartilage.