Visualizing the anatomic structures of human prostates using Acoustic Radiation Force Impulse (ARFI) imaging
McNeal's zonal anatomy for prostate has been the standard anatomical model for human prostate for about 30 years. It divides a human prostate into one non-glandular zone (the anterior flbromuscular stroma), and three glandular zones (central zone (CZ), transitional zone (TZ) and peripheral zone (PZ)). Visualizing these zones is of great importance for diagnosing prostate diseases. However, they are not well visualized by current ultrasound techniques. In this study, 3D Acoustic Radiation Force Impulse (ARFI) imaging has been implemented in order to visualize anatomic structures of excised human prostates. Prostate specimens were obtained immediately after radical prostatectomy and put in an isotonic saline bath at room temperature. ARFI data were acquired from the posterior side of the prostate using a Siemens Antares scanner and a VF10-5 linear array, whose imaging plane is the axial/lateral view in the normal anatomy. The position of the imaging transducer was controlled by a 3D translation stage. The scanner and the translation stage were programmed to scan the entire prostate specimen automatically with 1 mm spacing between elevation planes. 3D ARFI images with high spatial resolution were acquired for each specimen. Different zones and structures within the prostates have been well visualized in 3D ARFI images, which are in agreement with McNeal's zonal anatomy. Prostate lesions and benign prostatic hyperplasia were also detected and correlated with histopathological results. This study demonstrated that ARFI imaging is capable of visualizing internal structures and detecting suspicious lesions in the prostate.
