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101.
Objectives.?To determine whether growth velocity parameters derived from routine prenatal ultrasound measurements at first, second and third trimester can identify normal growth at term as well as late-onset growth abnormalities.

Material and methods.?Longitudinal study of fetal growth in normal singleton pregnancies with three normal ultrasound examinations and delivered at term. Fetuses were classified into 3 groups (?<?10th percentile, 10–90th percentile, >?90th percentile) based on birth weight. Multiple regression on birth weight classification was used to build up a prediction equation of fetal growth potential (FGP) based on fetal biometry and fetal growth velocity parameters between ultrasound examinations. Best cut-off value for FGP predicting growth restriction and macrosomia were defined.

Results.?356 pregnancies were included. Fetal biometry growth velocities between examinations were calculated for all measurements. Using best cut-off values, the estimated sensitivity, specificity and odds ratio were: 60% [44;74], 91%[89;92] and 14.55 [6.30;33.98] and 53% [36;69], 89%[88;91] and 10 [4.27;23.49] for the prediction of growth restriction and macrosomia, respectively.

Discussion.?Fetal growth potential can be derived and calculated from standard ultrasound measurements. It can improve identification of these fetuses at risk for late-onset growth abnormalities and their related morbidity.  相似文献   
102.
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104.
Schertz  LD; Lee  JK; Heiken  JP; Molina  PL; Totty  WG 《Radiology》1989,173(2):401-405
The contribution of proton spectroscopic (PS) imaging to magnetic resonance (MR) imaging of the liver was assessed at 0.5 T in 55 patients with known or suspected hepatic malignancy. PS images were compared subjectively with T1- and T2-weighted spin-echo (SE) images for hepatic lesion detection and conspicuity. For hepatic metastases (n = 27), PS images were equal to T1-weighted images in lesion detection in 17 patients but showed fewer lesions in five patients and false-negative results in two. When compared with T2-weighted images, PS images depicted more lesions in six patients, an equal number of lesions in 18, and fewer lesions in two. Hepatomas (n = 8) were detected with each sequence in all patients. Hepatomas were often more conspicuous on PS images than on T2-weighted images; they were of equal conspicuity on PS and T1-weighted images in most cases. Whereas fatty infiltration (n = 16) appeared on PS images as areas of low signal intensity similar to that of paraspinal muscle, it produced no detectable abnormality on either T1- or T2-weighted images. PS imaging is inferior to T1-weighted SE imaging in the detection of hepatic metastases. The major role of PS imaging at intermediate field strength is to differentiate focal fatty infiltration from hepatic metastases.  相似文献   
105.
McGahan  JP; Lindfors  KK 《Radiology》1989,173(2):481-485
Emergency percutaneous cholecystostomy was successfully performed in 39 of 40 attempted procedures in 37 hospitalized patients with possible acute cholecystitis. All cholecystostomies were performed with ultrasound guidance and preferentially with the transhepatic route, and all but four were performed at the patient's bedside. The patients had been hospitalized an average of 27 days before the procedure. Twenty-two of the 37 patients (59%) eventually died during hospitalization because of other medical or surgical problems. Only minor complications related to percutaneous cholecystostomy placement occurred in this series: catheter dislodgment without sequelae (n = 2) and significant abdominal pain (n = 2). Technical problems included guide-wire buckling during catheter insertion (n = 1) and failed attempted cholecystostomy (n = 1). Percutaneous cholecystostomy is a safe alternative to surgical cholecystostomy in the treatment of patients suspected of having acute cholecystitis.  相似文献   
106.
Magnetic resonance installation: siting and economic considerations   总被引:1,自引:0,他引:1  
Bradley  WG; Opel  W; Kassabian  JP 《Radiology》1984,151(3):719
  相似文献   
107.
Insertion of a screw biopsy stylet into a thin-walled biopsy needle greatly enhances detection of the needle during ultrasound-guided percutaneous biopsy. This technique is helpful when precise needle-tip localization is needed for biopsies of small lesions.  相似文献   
108.
What’s known on the subject? and What does the study add? Oxidative stress and inflammation are tissue‐ and cell‐level components of shock wave lithotripsy (SWL)‐induced acute renal injury, which we recently showed to be localized principally to the medulla within the focal zone of the lithotripter. This study reports that the magnitude of the oxidative stress and inflammation observed in the medulla after SWL is dependent on the number of shock waves delivered to the kidney, indicating that this is a sensitive measure of renal injury caused by shock waves. OBJECTIVE To determine if the magnitude of the acute injury response to shock‐wave lithotripsy (SWL) depends on the number of SWs delivered to the kidney, as SWL causes acute renal oxidative stress and inflammation which are most severe in the portion of the kidney within the focal zone of the lithotripter. MATERIALS AND METHODS Pigs (7–8 weeks old) received 500, 1000 or 2000 SWs at 24 kV from a lithotripter to the lower pole calyx of one kidney. At 4 h after treatment the kidneys were removed, and samples of cortex and medulla were frozen for analysis of the cytokine, interleukin‐6, and for the stress response protein, heme oxygenase‐1 (HO‐1). Urine samples taken before and after treatment were analysed for the inflammatory cytokine, tumour necrosis factor‐α. For comparison, we included previously published cytokine data from pigs exposed to sham treatment. RESULTS Treatment with either 1000 or 2000 SWs caused a significant induction of HO‐1 in the renal medulla within the focal zone of the lithotripter (F2, 1000 SWs, P < 0.05; 2000 SWs, P < 0.001). Interleukin‐6 was also significantly elevated in the renal medulla of the pigs that received either 1000 or 2000 SWs (P < 0.05 and <0.001, respectively). Linear dose–response modelling showed a significant correlation between the HO‐1 and interleukin‐6 responses with SW dose (P < 0.001). Urinary excretion of tumour necrosis factor‐α from the lithotripsy‐treated kidney increased only for pigs that received 2000 SWs (P < 0.05). CONCLUSION The magnitude of renal oxidative stress and inflammatory response in the medulla increased with the number of SWs. However, it is not known if the HO‐1 response is beneficial or deleterious; determining that will inform us whether SWL‐induced renal injury can be assessed by quantifying markers of oxidative stress and inflammation.  相似文献   
109.
Badami  JP; Baker  RA; Scholz  FJ; McLaughlin  M 《Radiology》1986,158(1):175-177
A group of 228 consecutive patients undergoing metrizamide myelography was prospectively evaluated for postprocedure symptoms. The observed prevalence of these symptoms concurs with previously reported inpatient studies, with the most common sequelae being exacerbation or onset of spine or extremity pain, headache, nausea, and paresthesia. Limitation of administered dose of metrizamide in lumbar myelography may slightly reduce the occurrence of common symptoms, but withdrawal of contrast medium at the completion of examination had no impact on their occurrence. There was a higher occurrence of paresthesia in cervical myelography, but otherwise there was no significant difference in symptoms between cervical and lumbar studies. Outpatient metrizamide myelography can be performed with relative safety with the potential for significant cost savings.  相似文献   
110.
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs.  相似文献   
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