Myocardial contrast echocardiography in human beings: correlation of resting perfusion defects to sestamibi single photon emission computed tomography.

The presence of myocardial perfusion abnormalities is generally accepted to suggest underlying coronary artery disease. In previous animal studies, myocardial contrast echocardiography (MCE) has been shown to be useful in delineating areas at risk after coronary occlusions. We sought to compare the presence or absence, size, and location of perfusion defects detected in human beings by MCE and sestamibi single photon emission computed tomography (SPECT).

Immunoassays for quantifying choriogonadotropin compared for assay performance and clinical application.

We examined calibration and accuracy, precision, sensitivity, specificity, and "hook" effects for recently revised automated choriogonadotropin (hCG) immunoassay systems (Baxter-Dade Stratus II, Abbott IMx intact hCG and total beta hCG) and compared them with a widely used immunoradiometric assay (Hybritech). We estimated hCG in pregnant women, women with trophoblastic disease, nonpregnant young and menopausal women, normal men, and men with testicular tumors. We found clinically unimportant differences in calibration (all calibrated to the 3rd International Standard).

Quantification of the reversibility of stress-induced thallium-201 myocardial perfusion defects: a multicenter trial using bull's-eye polar maps and standard normal limits.

A multicenter trial was performed on 140 patients from four centers to determine the accuracy of quantitative analysis of stress/delayed thallium-201 myocardial tomograms using normal limits to assess the relative amount of reversibility of stress-induced defects. The patients were found to have 85 fixed and 124 reversible defects, as determined by visual interpretation. Reversibility bull's-eye polar maps were compared to gender-matched normal limits from 36 normals.

Radionuclide bone/joint imaging in children with rheumatic complaints.

We reviewed the medical records and technetium bone/joint scans of 160 children presenting to the inpatient Pediatric Rheumatology service over a 3-year period. When the scan result (normal versus abnormal) was considered for each patient as a whole, scan sensitivity and specificity were both approximately 75%. However, when each joint was considered individually, sensitivity decreased to 37%, while specificity rose to more than 95% when compared to clinical examination.

Chemically blocked analog assays for free thyronines. I. The effect of chemical blockers on T4 analog and T4 binding by albumin and by thyroxin-binding globulin.

Analog assays for free thyroxin (FT4) produce inaccurate results because the T4 analog is sequestered by albumin. Diagnostic Products Corp. (DPC) introduced the concept of chemically blocking analog-albumin binding in 1982.