Real-time compounding of three-dimensional transesophageal echocardiographic volumes: the phantom study

3D ultrasound has attracted considerable interest in recent years as a low cost, mobile and real-time imaging modality for interventional cardiac applications. However, the low image quality and small field of view have been two major barriers preventing 3D ultrasound from being widely accepted as a solution to the guidance of cardiac interventions. By using the 3D transesophageal echographic (TEE) probe, it is possible to acquire images with better quality compared to the images acquired from traditional transthoracic probe (TTE). However, the 3D TEE volume has even smaller field of view and is insufficient to cover the whole geometry of the heart. Previously, we have developed a technique to compound 3D TTE volumes in real-time. In this study, we extend this technique to compound 3D TEE volumes by using an electromagnetic tracking system. In this pilot study, two different types of phantoms were used to evaluate our technique. The results suggest our method is accurate and efficient. The compounding error is approximately 2.5mm.