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151.
Simeone JF; Edelman RR; Stark DD; Wittenberg J; White EM; Butch RJ; Mueller PR; Brady TJ; Ferrucci JT Jr 《Radiology》1985,157(2):437-441
Eight healthy volunteers and 11 patients with pancreatic abnormalities were studied using a conventional body coil and a prototype magnetic resonance (MR) surface coil. Final pathologic diagnoses included carcinoma of the head (six), body (one), and tail of the pancreas (two) and chronic pancreatitis (two). In surface coil images of the volunteers, the body and tail of the pancreas was visualized in all cases but one, and the pancreatic duct was seen in five of eight cases. In-plane spatial resolution of 0.9 X 0.9 mm and 5-mm section thickness was obtained. At the same time, pancreatic surface coil images had a twofold improvement in the signal-to-noise ratio (SNR) compared with body coil images. T1-weighted spin-echo images gave greater SNR, reduced motion artifacts, provided superior anatomic detail, and offered more diagnostic information than comparable T2-weighted images. Significant abnormalities detected only by surface coil imaging included a small tumor surrounded by reactive edema and periglandular tumor invasion. This study demonstrates that surface coil imaging of the pancreas not only is feasible but provides an improved method for examining the pancreas by MR. 相似文献
152.
Metallic hip implants: CT with multiplanar reconstruction 总被引:4,自引:0,他引:4
Thirty consecutive patients with metallic implants in the hip were evaluated with both standard transaxial computed tomography (CT) and multiplanar reconstruction (MPR) to assess the contribution of MPR. The metallic devices included total hip replacements (n = 6), one or more surgical plates with screws (n = 9), acetabular pins or screws (n = 9), and Knowles pins (n = 6). The metallic implants were on the side of interest in 25 hips and in the contralateral hip in five cases. One patient had bilateral hardware. MPR reformats axially acquired data into other planes. The reconstruction program weights the true signal over the randomly distributed artifacts by integrating adjacent axial images. Examination using standard transaxial imaging was graded as excellent in five cases, adequate in 15 cases, and inadequate in ten cases. After MPR, 19 studies were classified as excellent, 11 were classified as adequate, and none were classified as inadequate. It is concluded that MPR significantly reduced artifacts caused by metal present in transaxial images. 相似文献
153.
ABSTRACT: In a prospective longitudinal study, 202 primigravidas were assessed for depression using the National Institute of Mental Health's (NIMH) standardized clinical interview, the Schedule for Affective Disorders and Schizophrenia (SADS), and Research Diagnostic Criteria (RDC) at four periods: 10 to 14 weeks of pregnancy, 30 to 32 weeks of pregnancy, 1 to 2 weeks postpartum, and 14 weeks postpartum. Women's responses did not fit the SADS standardized questions and prescribed ratings because pregnancy and postpartum symptoms often mimicked depression symptoms. This was addressed by adding questions and scoring criteria to separate out pregnancy and postpartum symptoms from depression symptoms. Results showed that, after accounting for pregnancy-postpartum symptoms, women consistently claimed eight symptoms with high frequency and higher mean ratings: dysphoric mood, worrying, somatic and psychic anxiety, insomnia, fatigue, anger, and irritability. The findings suggest that 1) depression in pregnant and newly delivered women may be underdiagnosed if caregivers attribute their complaints or symptoms to time-limited somatic conditions; 2) depression may be overdiagnosed if clinicians use self-report measures solely, or without carefully interviewing women to separate the symptoms of depression from symptoms of pregnancy and postpartum; and 3) women's reactions to perinatal symptoms may have some bearing on the development of depression then or later. Simple clinical and social amelioration of the symptoms of distress might reduce their effect and diminish the rate of mistaken diagnoses of depression. 相似文献
154.
Edelman RR; McFarland E; Stark DD; Ferrucci JT Jr; Simeone JF; Wismer G; White EM; Rosen BR; Brady TJ 《Radiology》1985,157(2):425-430
Prototype surface coil magnetic resonance (MR) images were obtained from phantoms and 42 subjects at 0.6 T to assess the feasibility of imaging relatively deep abdominal structures. Surface coil images demonstrated a two- to fourfold improvement in signal-to-noise ratio (SNR) when compared with whole-body coil images with the same resolution elements. This improvement in SNR allowed us to obtain images with thinner sections, higher in-plane resolution, or, alternatively, a decrease in image time. Compared with body images, surface coil images demonstrated greater anatomic detail and reduction in motion artifacts. Despite the limited field of view in very large patients, the use of surface coils improves the diagnostic capability of MR imaging of the abdomen. 相似文献
155.
Stark DD; Moseley ME; Bacon BR; Moss AA; Goldberg HI; Bass NM; James TL 《Radiology》1985,154(1):137-142
Experimental animals that had been given excess iron in their diet were studied by magnetic resonance (MR) imaging in vivo and by magnetic resonance (MR) spectroscopy in vitro. Hepatic iron overload in patients with transfusional iron excess was studied by MR imaging, and isolated iron protein fractions were studied in vitro by MR spectroscopy. The spin echo image intensity of livers with iron overload was decreased because of the extreme decreases in T2 compared with normal; T1 was decreased only moderately. The relaxation rates 1/T2 and 1/T1 both showed a linear relationship to hepatic iron levels. Ferritin solutions showed moderate decreases in T2 and mild decreases in T1. The T2 relaxivity of ferritin, which is due to the iron core rather than the apoferritin protein shell, does not appear sufficient to account for the extreme decrease in T2 observed in hepatic iron overload. Low molecular weight cytosol iron is present in lower concentrations than ferritin but potentially has much greater relaxivity and may contribute to the MR findings. These techniques may be useful in other studies of iron metabolism. 相似文献
156.
157.
O R Affonso C V de Moura V Cavallari E Mitidieri 《Anais da Academia Brasileira de Ciências》1981,53(3):617-620
Liver X.O. activity does not change significantly in tumor bearers although it is known that in this case there is a severe protein deficiency (hypoproteinosis). A decrease in the blood serum X.D. activity was observed in tumor bearing rats but no change occurred in the level of the plasmatic protein. It was suggested that the fall in the blood serum enzyme can be due to factors not correlated with the protein deficiency due to the animals inanition. 相似文献
158.
159.
160.
Esophageal food impaction: treatment with glucagon 总被引:7,自引:0,他引:7