Recently, microvessel imaging at super resolution using contrast agents has been successfully demonstrated. However, the computational costs associated with the processing is extremely high. To overcome some of the computational issues, new techniques for generating high-resolution microvessel images with contrast MBs are warranted. One computationally inexpensive technique to realize high-resolution microvessel imaging is to use null subtraction imaging (NSI) . NSI uses nulls in the beam pattern to produce images at much higher apparent lateral resolution and is especially suited for sharpening ultrasound images of specular scatters like MBs. In this study we acquired 1000 frames of ultrasonic data of chicken embryo with microbubble as contrast agent inside and utilized NSI to attain image with improved spatial resolution compared with traditional delay and sum image.