Faster, More Accurate Diffusion Filtering for Fetal Ultrasound Volumes

3D ultrasound is a unique medical imaging modality for observing the growth and malformation of the fetus. But it is necessary to enhance its visual quality by filtering to reduce speckle noise and artifacts. Because imaging of fetuses takes place real time, these processes must also be fast. Previous methods have limited speed, quality, or are only applicable to 2D. We propose a new 3D filtering technique for 3D US fetus volume data which classifies the volume according to local coherence and applies different filters to the volume of interest and to the rest of the 3D image. The volume of interest, which contains the fetus, is determined automatically from key frames, and is processed using a nonlinear coherence enhancing diffusion (NCED) filter. Our method enhances 3D US fetus images more effectively than previous techniques, runs more quickly, and reduces the number of artifacts because it is a true extension to 3D.