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101.
Miller DL; Simmons JT; Chang R; Ward BA; Shawker TH; Doppman JL; Chang AE 《Radiology》1987,165(3):785-790
A prospective, blinded comparison of three methods of hepatic contrast enhancement in computed tomography (CT) was conducted in 15 patients with colorectal carcinoma metastatic to the liver. Arterial portography (AP-CT) was performed with injection of contrast material into the superior mesenteric artery during CT. Delayed scanning (DS-CT) was performed 4 hours after intravascular administration of contrast material (mean dose, 280 mL). CT with an ethiodized oil emulsion (EOE-CT) was performed 1 hour after slow intravenous infusion of the emulsion. All patients underwent laparotomy following imaging studies. A lesion-by-lesion analysis of 56 metastases showed no significant differences in sensitivity (AP-CT, 77%; DS-CT, 83%; EOE-CT, 82%), but the false-positive rate for AP-CT was significantly higher than that for DS-CT (P less than .001) or EOE-CT (P less than .01). False-positive rates for EOE-CT and DS-CT were not significantly different. The predictive value of a positive test was 63% for AP-CT, 90% for DS-CT, and 81% for EOE-CT. AP-CT does not appear to be clinically useful for detection of hepatic metastases because of the high false-positive rate. No difference could be demonstrated between DS-CT and EOE-CT. DS-CT is a valuable method for hepatic contrast enhancement. 相似文献
102.
Elizondo G; Weissleder R; Stark DD; Todd LE; Compton C; Wittenberg J; Ferrucci JT Jr 《Radiology》1987,165(3):795-800
Magnetic resonance images were obtained before and after treatment in 17 patients with 29 amebic liver abscesses. Pretreatment T1-weighted images showed a sharply circumscribed, heterogeneous, low-signal-intensity mass, devoid of normal hepatic tissue and corresponding to the abscess cavity as measured sonographically. T2-weighted images showed the abscess cavity as a hyperintense region and also showed a larger region of hyperintensity extending from the cavity margins to the liver surface, corresponding to edematous but morphologically normal liver tissue. After treatment, the abscess cavity became homogeneously hypointense on T1-weighted images, corresponding to liquefaction of the abscess center. With successful treatment, concentric rings corresponding to (a) an inner margin of inflamed granulation tissue, (b) bands of type I collagen, and (c) the outer margin of atrophic and/or mildly inflamed liver tissue became prominent on T1- and T2-weighted images. T2-weighted images showed rapid resolution of the perifocal hepatic edema. 相似文献
103.
104.
105.
Van Lysel MS; Dobbins JT d; Peppler WW; Hasegawa BH; Lee CS; Mistretta CA; Zarnstorff WC; Crummy AB; Kubal W; Bergsjordet B; Strother CM; Sackett JF 《Radiology》1983,147(3):869-874
Initial clinical results using a digital fluoroscopic implementation of the combined time-energy ("hybrid") subtraction technique are described, with emphasis on carotid and renal imaging. Where patient motion artifacts are due to soft-tissue motion alone, hybrid subtraction can remove them. Due to the need for a finite separation time between high- and low-energy pairs, however, the present implementation of the hybrid technique is not completely immune to soft-tissue motion. The intrinsic signal-to-noise ratio of hybrid imaging is less than that of conventional temporal subtraction. However, since the low-energy temporal subtraction images are included in the hybrid data set, the diagnostic quality of the examination is not compromised. 相似文献
106.
Ton AF Lenssen Mike JA van Steyn Yvonne HF Crijns Eddie MH Waltjé George M Roox Ruud JT Geesink Piet A van den Brandt Rob A De Bie 《BMC musculoskeletal disorders》2008,9(1):60
Background
Adequate and intensive rehabilitation is an important requirement for successful total knee arthroplasty. 相似文献107.
108.
A retrospective study of pretransfusion testing records compared the utility of the antiglobulin test (AGT) phase of the crossmatch and the autologous control (autocontrol) for detecting clinically significant alloimmunization to red cells (RBCs). Of 110,780 consecutive crossmatches, 141 were positive after a negative antibody screening test; only 4 of these were due to alloantibodies of potential clinical significance, for a predictive value of a positive AGT crossmatch, after a negative antibody screen, of 2.8 percent (4/141). The frequency of potentially shortened RBC survival was 1 in 27,685 units crossmatched. During a similar period, 56,090 autocontrols were performed with the antibody screen. The autocontrol was positive on 902 samples in which the antibody screen was negative. Antibody identification performed in 684 cases generally yielded only cold or warm autoagglutinins. In 96 cases, some form of alloantibody was detected, but only 25 had potential clinical significance by our criteria. Eight of these alloantibodies had concurrently caused in vivo sensitization of RBCs and were classified as delayed hemolytic transfusion reactions. The predictive value of the autocontrol, calculated as the number of significant alloantibodies detected in autocontrol-positive, antibody-screen-negative samples, was 3.6 percent (25/684). Inspection of these cases revealed 11 in which shortened RBC survival might have resulted if the serologic abnormality had not been detected. Thus, the autocontrol had a slightly greater yield of clinically significant findings than the AGT crossmatch.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
109.
Detecting fetomaternal hemorrhage: a comparison of five methods 总被引:3,自引:0,他引:3
KM Bayliss ; BD Kueck ; ST Johnson ; JT Fueger ; PW McFadden ; D Mikulski ; JL Gottschall 《Transfusion》1991,31(4):303-307
Appropriate postpartum administration of Rh immune globulin relies on sensitive detection and accurate quantitation of fetomaternal hemorrhage (FMH). Recently, the microscopic Du test (micro Du) enhanced with polyethylene glycol (PEG Du) and flow cytometry (FC) have been advocated for this purpose. Three qualitative methods (micro Du, rosette test, and PEG Du) and two quantitative methods (acid elution and FC) for assessing FMH were evaluated with particular attention given to PEG Du and FC. In vitro studies comprised 10 series of dilutions of D+ cord cells in D- adult cells to yield D+ cell concentrations of 0.06, 0.12, 0.25, 0.50, 0.75, 1.0, and 2.0 percent. Additionally, 26 postpartum samples were tested. Of the qualitative techniques, the micro Du test was the least sensitive with 20 percent false-negative results occurring at 0.5 percent fetal cells. The PEG Du test was only slightly more sensitive and offered no clinical advantage. The rosette test was the most sensitive, consistently detecting fetal cells at concentrations of 0.25 percent or greater. FC and acid elution showed similar results, with good correlation obtained between measured and expected quantities of fetal cells (r = 0.99 and 0.96, respectively). One of 26 postpartum samples was positive by all screening techniques; acid elution and FC detected 0.3-percent concentrations of fetal cells and 0.17-percent concentrations of D+ cells, respectively. Although acid elution is a more commonly used method for quantitating FMH, FC offers an acceptable alternative that is capable of analyzing large numbers of cells with objectivity and reproducibility. 相似文献
110.
Wegener's granulomatosis: long-term follow-up of patients treated with pulse cyclophosphamide 总被引:3,自引:1,他引:3
Treatment with daily oral cyclophosphamide (CY) has improved survival in
Wegener's granulomatosis (WG), but is associated with severe and
potentially lethal adverse effects. Less toxic treatment regimens, such as
pulse CY, have been used, but the effect has been questioned. We have
treated 11 patients with WG with pulse CY (15 mg/kg initially every second
week, gradually increasing the pulse interval). After 4.5 yr follow-up and
a total of 501 pulses of CY, one patient died and eight patients (73%) were
in complete remission. Remission was induced in 91% of the patients after a
median period of 3.5 months and relapses were seen in 60%. With the same
treatment protocol, a new complete remission was induced in 75% of those
relapsing. Except for one patient who died, no patient developed end-stage
renal failure. Haemorrhagic cystitis was not observed and no malignancies
recorded. Severe infections were seen in 36%, but none caused by
Pneumocystis carinii. Nausea was the most frequent side-effect, seen in 64%
of the patients. We conclude that treatment with pulse CY every second week
is safe and effective in inducing remission and treating relapses in WG.
The relapse rate seems to be higher than with low-dose oral CY, but the
cumulative dose of CY is less.
相似文献