Investigative radiology
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Investigative radiology · Feb 2004
Comparative StudyDual-probe radiofrequency ablation: an in vitro experimental study in bovine liver.
To determine whether alternative radiofrequency (RF) application with dual probes has advantages over sequential or simultaneous RF application for creating larger coagulation necrosis. ⋯ The alternative RF application creates larger, more regular ablation zones than either the sequential or simultaneous RF application. This result suggests that use of an alternating RF power application will improve the results of RF ablation for the treatment of larger tumors.
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Investigative radiology · Jan 2004
Relationship between cerebrospinal fluid and blood dynamics in healthy volunteers and patients with communicating hydrocephalus.
Using magnetic resonance imaging (MRI), we investigated cerebral blood and cerebrospinal fluid (CSF) flows in patients with communicating hydrocephalus (CH) and in healthy volunteers to determine the contribution of CSF flow to brain pressure regulation in CH patients. ⋯ Venous vessel compression and/or changes in intracranial subarachnoid CSF flow produce an increase in ventricular CSF flush that compensates for vascular brain expansion in patients with CH.
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Investigative radiology · Nov 2003
Potential of magnetic resonance lymphography with intrapulmonary injection of gadopentetate dimeglumine for visualization of the pulmonary lymphatic basin in dogs: preliminary results.
To evaluate a new approach of magnetic resonance (MR) lymphography with intraalveolar injection of a conventional extracellular contrast agent (gadopentetate dimeglumine) for imaging lymphatic basin draining from specific portions of the lung. ⋯ MR lymphography with low-concentration gadopentetate dimeglumine can quickly and sufficiently visualize the drainage lymphatic station from specific lung portions, and may have the potential of sentinel node mapping in lung cancer.
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Investigative radiology · Sep 2003
Comparative StudyAutomatic model-based contour detection and blood flow quantification in small vessels with velocity encoded magnetic resonance imaging.
The quantitative assessment of blood flow in peripheral vessels from phase-contrast magnetic resonance imaging studies requires the accurate delineation of vessel contours in cross-sectional magnetic resonance images. The conventional manual segmentation approach is tedious, time-consuming, and leads to significant inter- and intraobserver variabilities. The aim of this study was to verify whether automatic model-based segmentation decreases these problems by fitting a model to the actual blood velocity profile. ⋯ Blood flow in magnetic resonance images of small vessels can be assessed accurately, rapidly, and fully automatically using model-based postprocessing by fitting a first approximation of the velocity profile to the actual flow data.
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Investigative radiology · Aug 2003
Comparative StudyTime-related changes of radiofrequency ablation lesion in the normal rabbit liver: findings of magnetic resonance imaging and histopathology.
To study time-related magnetic resonance imaging (MRI) and histopathological findings after radiofrequency ablation (RFA) in the normal liver. ⋯ The time-related pathologic changes of RFA lesions in rabbit livers can be reflected as laminar patterns on MR images. Understanding of the zone structure of the lesions is useful for the evaluation of follow-up MRI.