POTENTIAL ADDED VALUE OF 3-DIMENSIONAL RECONSTRUCTION AND DISPLAY OF SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHIC GATED BLOOD-POOL IMAGES

Background Single photon emission computed tomographic (SPECT) acquisi tion provides potential advantages for blood pool imaging. However, th e method has been little applied. Methods. An improved method of three -dimensional (3-D) reconstruction and display of SPECT equilibrium blo od pool scintigrams and related phase data was developed, Dynamic slic es and volume-rendered dynamic 3-D images were displayed. Images were viewed from each of 34 solid angles referenced to a sphere surrounding the reconstruction field. Each image pixel was ''painted'' with inten sity-coded regional amplitude and color-coded for its phase angle, The method was applied to evaluate the cardiac anatomy, regional contract ion, and related conduction sequence at rest in 17 patients, Twelve ha d normal left ventricular function including 7 patients with minimal s eptal preexcitation. Five patients had abnormal left ventricular funct ion, including 2 with left bundle branch block. Results. Slices contai ned all of the functional information, but necessary data integration was time-consuming and evaluation of chamber size and anatomy was diff icult. Three-dimensional projection images condensed and integrated th e data, presenting new vantage points on anatomy, contraction, and con duction not otherwise available in the clinically limited angulations of planar images, This provided excellent visual separation of cardiac chambers with full and increased visualization of right and left vent ricular wall motion in all segments compared with the conventional pro jections acquired clinically (p < 0.05). Atria and great vessels were well separated with evident size and function. Phase-angle progression paralleled the electrocardiogram, permitting bypass pathway localizat ion and the direct noninvasive localization of posteroseptal pathways. Conclusions. The 3-D method permits greater access to and utilization of SPECT blood pool image data. It suggests specific advantages for c linical use.