title: The bifocal diverging collimator: a means of simultaneous biplane imaging of the heart during equilibrium radionuclide ventriculography.
abstract: We have constructed a bifocal diverging collimator (BDC), capable of simultaneously recording two views of the heart 50 degrees apart on each half of a standard imaging field. In this study, simultaneous two-view blood-pool scans using the BDC were compared with the same two separate views obtained using an all-purpose parallel-hole collimator (PHC), assessing left-ventricular ejection fraction and regional wall motion in 20 patients undergoing contrast left ventriculography (CV). Ejection fraction by BDC correlated closely with PHC (r = 0.94) and with CV (r = 0.88). Regional wall motion was scored qualitatively on a five-point scale from 3 (normal) to--1 (dyskinesis) with an 88% agreement between BDC and PHC and PHC for segment scores. The percentages for agreement between BDC and CV, and between PHC and CV, were identical, 79%. A single blood-pool scan acquisition using a new BDC provides information about global and regional left-ventricular function in two planes, comparable with that of a PHC.
mesh_terms: D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011756:Diphosphates; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D007089:Image Enhancement; D011877:Radionuclide Imaging / Q000295:instrumentation* / Q000379:methods; D013667:Technetium; D013793:Thallium
chemical_list: D011756:Diphosphates; D013667:Technetium; D013793:Thallium