1080-2 Indexing and Summarization of Echocardiogram Videos

Background: The pericardial effusion volume (PEV) does not possess a known regular shape. Therefore, the standard methods for volume estimation based on 2-D echooardiography can not be / / applied. This study was conducted to evaluate a new computer algorithm for acoustic quantification of PEV. Methods: Borders of the pericardial sac and the heart were identified either by hand tracing or with the help of an automated border detection algorithm in the apical 4-chamber view. A 3-D disk model was developed to represent the pericardium and the heart with stacks of circular or eltipficai disks along the long axis. Volumes were calculated based on the modified Simpson's rule. For comparison the standard area-length method for volume estimation was also applied. PEV was determined as the difference between the pericardial volume and the heart volume. The methods were implemented in C++ for the Macintosh computer. Results: Preliminary results demonstrated the advantage of the 3-D disk model for asymmetric and non-ellipsctdai volumes. For the example shown in the figure PEV was estimated to be 657 ml by the 3-D disk model and 523 ml by the area-length method. The actual fluid volume drained was 700 ml. Conclusion: The 3-D disk model does not rely on the assumption of symmetrical and ellipsoidal volumes. The software should be useful for obtaining an accurate estimate of the pericardial effusion volume by use of 2-D echocardiography.