Ma. Bray et al., Three-dimensional surface reconstruction and fluorescent visualization of cardiac activation, IEEE BIOMED, 47(10), 2000, pp. 1382-1391
Optical imaging of transmembrane potentials in cardiac tissue is a rapidly
growing technique in cardiac electrophysiology. Traditional studies typical
ly use a monocular imaging setup, thus limiting investigation to a restrict
ed region of tissue, However, studies of large-scale wavefront dynamics, es
pecially those during fibrillation and defibrillation, would benefit from v
isualization of the entire epicardial surface. To solve this problem, a pan
oramic cardiac visualization algorithm was developed which performs the two
tasks of reconstruction of the surface geometry of the heart, and represen
tation of the panoramic fluorescence information as a texture mapping onto
the geometry that was previously created, This system permits measurement o
f epicardial electrodynamics over a geometrically realistic representation
of the actual heart being studied. To verify the accuracy of the algorithm,
the procedure was applied to synthetic images of a patterned ball; further
verification was provided by application of the algorithm to a model heart
placed in the experimental setup, Both sets of images produced mean regist
ration image errors on the order of 2 pixels, corresponding to roughly 3 mm
on the geometry. We demonstrate the algorithm by visualizing epicardial wa
vefronts on an isolated, perfused rabbit heart.