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排序方式: 共有1812条查询结果,搜索用时 31 毫秒
1.
Irmak Karaca Suzan Güven Yılmaz Melis Palamar Halil Ateş 《Ocular immunology and inflammation》2020,28(6):947-951
ABSTRACT
Purpose
To investigate the effect of 1% tropicamide on anterior chamber aqueous flare (ACAF) measurements acquired with laser flare meter in patients with pseudoexfoliation. 相似文献2.
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David L Reich Loren M Horn Sabera Hossain Suzan Uysal 《European journal of cardio-thoracic surgery》2004,25(3):401-6; discussion 406-8
OBJECTIVES: Deep hypothermic circulatory arrest (DHCA) is commonly used during thoracic aortic surgery, and is initiated only after a sufficient degree of cerebral hypothermia is induced. The criteria for initiating DHCA vary among institutions: most centers use temperature criteria, some use electroencephalography, and a minority use jugular bulb oxyhemoglobin saturation SjO(2) criteria. The purpose of this study was to determine whether the use of SjO(2) monitoring to guide the onset of DHCA was associated with better post-operative neuropsychological outcome. METHODS: Sixty-one thoracic aortic surgical patients underwent both pre- and post-operative neuropsychological testing. Patients were divided into three groups: (1) those with SjO(2)> or =95% at DHCA onset; (2) those with SjO(2)<95% at DHCA onset; and (3) those without SjO(2) monitoring. RESULTS: There were no statistically significant differences in the incidence of post-operative decline in neuropsychological function among the three groups of patients. Patients in whom SjO(2) data were used to guide onset of DHCA had lower esophageal and bladder temperatures at that time compared with patients without SjO(2) monitoring. CONCLUSIONS: Monitoring of SjO(2) had no apparent effect upon post-operative neuropsychological outcome, and there were no trends in our small patient cohort suggesting differences that our study was not adequately powered to detect. Use of SjO(2) monitoring was associated with more profound hypothermia prior to DHCA due to more prolonged cooling in attempts to bring the SjO(2) above the 95% threshold. Using our institutional cooling protocol, SjO(2) monitoring does not appear to increase neuroprotection in patients undergoing DHCA for thoracic aortic repairs. 相似文献
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Abdou Elhendy Marcel L. Geleijnse Ron T. van Domburg Jeroen J. Bax Peter R. Nierop Suzan A. M. Beerens Roelf Valkema Eric P. Krenning M. Mohsen Ibrahim Jos R. T. C. Roelandt 《European journal of nuclear medicine and molecular imaging》1997,25(1):69-78
Stress echocardiography has been considered an accurate method for the diagnosis of coronary artery disease in hypertensive
patients and in patients with left ventricular hypertrophy. In contrast, the specificity of myocardial perfusion scintigraphy
in these patients has been questioned. The aim of this study was to compare the accuracy of these two imaging modalities in
conjunction with dobutamine stress test for the diagnosis of coronary artery disease in hypertensive patients with and without
left ventricular hypertrophy. Dobutamine (up to 40 μg kg–1min–1) stress echocardiography in conjunction with sestamibi (MIBI) single-photon emission tomography (SPET) was performed in 84
patients with the diagnosis of systemic hypertension who had been referred for evaluation of myocardial ischaemia. Ischaemia
was defined as new or worsened wall motion abnormalities at echocardiography and reversible perfusion defects at SPET. Significant
coronary artery disease (≥50% luminal diameter stenosis) was detected in 66 patients (79%). The sensitivity, specificity and
accuracy of the ischaemic pattern at echocardiography for the diagnosis of coronary artery disease were 73% (CI 63%–82%),
83% (CI 75%–91%) and 75% (CI 66%–84%), those for MIBI were 67% (CI 57%–77%), 83% (CI 75%–91%) and 70% (CI 60%–80%) respectively
(P = NS vs echocardiography). Significant stenosis was detected in 123 (49%) of the 252 analysed coronary arteries. The sensitivity,
specificity and accuracy of echocardiography for the regional diagnosis of coronary artery disease were 63% (CI 56%–69%),
90% (CI 86%–94%) and 77% (CI 72%–82%). Those for MIBI were 58% (CI 51%–64%), 91% (CI 87%–94%) and 75% (CI 69%–80) respectively
(P = NS vs echocardiography). Left ventricular hypertrophy was detected in 59 patients (70%) by echocardiography and did not
influence the overall or regional specificity of echocardiography or MIBI SPET. It is concluded that in hypertensive patients,
dobutamine stress echocardiography and MIBI SPET have a comparable accuracy for the overall and regional diagnosis of coronary
artery disease. Hypertensive patients with or without left ventricular hypertrophy should not be considered unsuitable candidates
for stress myocardial perfusion scintigraphy.
Received 10 July and in revised form 19 September 1997 相似文献
9.
Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
10.
Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis. 相似文献