Keith C. Fischer

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UNLABELLED Patients with rising prostate-specific antigen (PSA) levels after definitive local therapy of prostate carcinoma present a diagnostic dilemma. A local recurrence would be amenable to additional local therapy with curative intent, whereas metastatic disease would require palliative androgen ablation therapy. In this study, we evaluated the(More)
PURPOSE To compare the diagnostic sensitivity of posteroanterior and lateral dual x-ray absorptiometry (PA-DXA, L-DXA, respectively) and quantitative computed tomography (CT). MATERIALS AND METHODS Among 108 women undergoing lumbar spine bone mineral density assessment, 66 were healthy (mean age, 52.9 years +/- 1.2 [standard error of mean]) and 42 had(More)
In an unselected series of patients whose only perfusion abnormalities on lung scan matched abnormalities on chest radiograph, the prevalence of pulmonary embolism ranged from 8 to 15%. These estimates depended upon whether only angiographic and autopsy-proven diagnoses were allowed or whether clinical diagnoses were also considered correct. Physical(More)
Dual energy radiography (DER) has been recently proposed as a new technique for the non invasive measurement of vertebral mineral density. This preliminary study was undertaken to assess the short-term precision of DER and to compare DER to dual photon absorptiometry (DPA) measurements. Three DER measurements were obtained in 19 healthy volunteers (mean age(More)
Each of 36 patients was studied with two separate brain scans performed sequentially after the injection of 20 mCi of 99mTc-pertechnetate or 20 mCi of 99mTc(Sn)-diphosphonate. The resulting scans were qualitatively compared, and lesion-to-nonlesion ratios of activity determined. Diagnoses were established by clinical criteria and were supported in the(More)
Thallium-201 myocardial scintigraphy was performed in patients with congenital heart defects to determine whether, by quantification of right ventricular isotope uptake, one could assess the degree of right ventricular hypertrophy and so predict the level of right ventricular pressure. A total of 24 patients ranging in age from 7 months to 30 years was(More)