Three-dimensional reconstruction of echo-cardiographic images using the rotation method.
We describe a method for three-dimensional reconstruction of real time two-dimensional echocardiographic images using a rotation method. Seven tissue specimens were studied in a water bath and two-dimensional images were recorded by rotating the transducer every 30 degrees, from 0 to 180 degrees. Angular reconstruction of areas was obtained at different axial locations and volumes calculated by a Sigma 9 computer using axial summation without geometric assumptions. Using spatial coordinate data, three-dimensional perspective images could be plotted by the computer in any desired view. The volumes obtained by this method (range 90-231 ml) corresponded closely (R = 0.96) with volumes measured directly by water displacement (range 95-200 ml). Two patients were also studied with this technique by placing the transducer at the cardiac apex to record two-dimensional left ventricular and diastolic and end systolic images. Three-dimensional reconstructed volumes closely correlated with those obtained by left ventricular angiography. Ejection fraction in one patient was 52% by three-dimensional reconstruction, 47% by angiocardiography. In the other patient, the ejection fraction was 76% by three-dimensional imaging, 69% by angiocardiography. This preliminary study demonstrates the feasibility and simplicity of three-dimensional reconstruction using the rotation method.