title: Radionuclide angiocardiography. Improved diagnosis and quantitation of left-to-right shunts using area ratio techniques in children.
abstract: A comparison of several reported methods for detection and quantitation of left-to-right shunts by radionuclides was performed in 50 children. Count ratio (C2/C1) techniques were compared with the exponential extrapolation and gamma function area ratio techniques. C2/C1 ratios accurately detected shunts and could reliably separate shunts from normals, but there was a high rate of false positives in children with valvular heart disease. The area ratio methods provided more accurate shunt quantitation and a better separation of patients with valvular heart disease than did the C2/C1 ratio. The gamma function method showed a higher correlation with oximetry than the exponential method, but the difference was not statistically significant. For accurate shunt quantitation and a reliable separation of patients with valvular heart disease from those with shunts, area ratio calculations are preferable to the C2/C1 ratio.
mesh_terms: D000293:Adolescent; D001017:Aortic Coarctation / Q000175:diagnosis; D001024:Aortic Valve Stenosis / Q000175:diagnosis; D006328:Cardiac Catheterization; D002648:Child; D002675:Child, Preschool; D003936:Diagnosis, Computer-Assisted; D006330:Heart Defects, Congenital / Q000175:diagnosis*; D006344:Heart Septal Defects, Atrial / Q000175:diagnosis; D006345:Heart Septal Defects, Ventricular / Q000175:diagnosis; D006349:Heart Valve Diseases / Q000175:diagnosis*; D006801:Humans; D007223:Infant; D008433:Mathematics; D008944:Mitral Valve Insufficiency / Q000175:diagnosis; D008946:Mitral Valve Stenosis / Q000175:diagnosis; D011666:Pulmonary Valve Stenosis / Q000175:diagnosis; D011877:Radionuclide Imaging / Q000379:methods*; D012044:Regression Analysis; D013667:Technetium; D014188:Transposition of Great Vessels / Q000175:diagnosis
chemical_list: D013667:Technetium