被服に対する意識及び行動とそれに影響する要因

博士（学術）神戸大

Le diagnostic ultrasonore des métastases hépatiques

SCOPUS: NotDefined.jinfo:eu-repo/semantics/publishe

CT doses in children: a multicentre study

We evaluated examination protocols used for common CT procedures of paediatric patients at different hospitals in Belgium in order to determine whether adjustments related to patient size are made in scanning parameters, and to compare patient doses with proposed reference levels. Three paediatric hospitals and one non-paediatric hospital participated in the study. Weighted CT dose-index (CTDIw), dose-length product (DLP) and effective dose (E) were evaluated for three patient ages (1 year, 5 years and 10 years) and three common procedures (brain, thorax and abdomen). CTDIw and DLP values higher than the reference levels were found for all types of evaluated examination. E ranged from 0.4 mSv to 2.3 mSv, 1.1 mSv to 6.6 mSv, and 2.3 mSv to 19.9 mSv for brain, thorax and abdomen examinations, respectively. All centres but one adapted their protocols as a function of patient size. However, no common trend in the selection of protocols was observed. Some centres divided the whole range of patient size into only two/three groups by age, while others classified the patients into six groups by weight. It was also observed that some centres used the same mAs for the total range of patient sizes and decreased the pitch factor for small children, which resulted in higher doses. This indicates the importance of careful selection of technical scan parameters. If CT parameters used for paediatric patients are not adjusted on the basis of examination type, age and/or size of the child, then some patients will be exposed to an unnecessarily high radiation dose during CT examinations

Laparoscopic evaluation of computed tomography (CT) and ultrasonography (US) in liver and abdominal tumor dissemination

73 patients porteurs d'une affection maligne histologiquement prouvée ont été soumis à une laparoscopie avec biopsies guidées sous contrôle de la vue, à une tomographie computée (TC) et/ou à une ultrasonographie (US). La laparoscopie a été utilisée comme test de référence. Le taux de faux négatifs est de 4 (TC) et 8 % (US). La plupart de ces cas sont observés parmi les lymphomes et les affections hématologiques qui sont mieux investigués par la laparoscopie et des biopsies guidées. L'envahissement tumoral du péritoine et la réponse à la chimiothérapie anticancéreuse n'ont pas été reconnus par ces méthodes. Le taux de faux positifs est de 4 (TC) et 14 % (US). Il pourrait être surestimé dans la mesure où la laparoscopie ne permet pas de démontrer avec certitude l'absence de métastase. Ces résultats préliminaires, quoique difficiles à interpréter en terme de précision des méthodes, mettent l'accent sur l'apport de la TC et de l'US dans l'identification des métastases hépatiques

Pituitary microadenomas: diagnosis with two-and three-dimensional MR imaging at 1.5 T before and after injection of gadolinium.

The usefulness of different magnetic resonance (MR) imaging sequences (coronal and sagittal spin-echo [SE] and three-dimensional fast low-angle shot [3D FLASH]) in the detection of pituitary microadenomas before and after gadolinium injection was prospectively evaluated in 28 patients with surgical confirmation. When evaluated separately, the most useful sequences in the detection of these microadenomas were coronal pregadolinium T1-weighted SE, coronal pregadolinium 3D FLASH, coronal postgadolinium T1-weighted SE, and coronal postgadolinium 3D FLASH. The combination of pre- and postgadolinium T1-weighted sequences with pre-and postgadolinium 3D FLASH sequences produced the highest number of true-positive findings (90%) and the lowest number of false-positive findings (5%). When a 1.5-T imaging unit with a high signal-to-noise ratio allowing useful three-dimensional acquisition is used, the authors advocate a coronal T1-weighted SE sequence, followed (if necessary) by a coronal 3D FLASH sequence, both without injection of gadolinium, in the diagnosis of pituitary microadenomas. When no confident diagnosis is reached, the same sequences should be performed after the injection of gadolinium. The sagittal pre- and postgadolinium T1-weighted SE and long-TR SE sequences are useful only in specific cases

Editing with a three RF pulse sequence for NMR proton surface coil spectroscopy

SCOPUS: ar.jinfo:eu-repo/semantics/publishe