P3J-1 A Novel Multi-Focus Image Reconstruction Technique in High Frequency Ultrasound

Due to the lack of arrays operating at frequencies above 20 MHz, all scanning at these frequencies must be performed mechanically with a fixed depth of field (DOF) transducer. To obtain the required diagnosis information from different depths, brightness/depth (B/D) scanning technique has been used in previous study. We found that the image variance in the focus region is larger than that in unfocus region. Thus, the image variance was adopted as an index to determine which B/D image providing focus information at specific depths. Finally, the significant focus regions were selected and reconstructed to a complete multi-focus image. The variance ratio between selected regions was addressed as a weighting factor to smooth the overlap boundary by linear interpolation method. Potential applications of this technique include high-resolution 3D tumor images in small animals. Speckle tracking will be applied across acquired frames to remove the challenging physiologic motion artifacts