3D reconstruction of prostate from ultrasound images

The aim of our study was to obtain a 3D model of the prostate from the ultrasound images and to represent it and calculate its volume. The establishing of prostate volume represents a necessary stage in choosing the method of solving prostate adenoma. The evaluation of the prostate volume can be done by transabdominal or endorectal echography. If the second method is not available it is necessary to use the echographic estimation of the volume of the prostate adenoma by suprapubian examination. This method lacks precision. In order to have a more accurate calculation of the prostate's volume than the ellipsoid approximation given by the echographic equipment, we designed a software tool for handling and management of digital images. The primary information is composed of two 2D digital images obtained by digitising the frames acquired from an 3.5 MHz ultrasound equipment for two incidences: sagittal and transversal. The bitmaps were filtered to reduce the noise and a contour detection algorithm was used. Further, the new 2D detected contours were processed with the help of an interactive image editor toward a 3D reconstruction of the prostate. The examiner can perform rotations and translations on the 2D projections and can adjust the angle between them. The resulting object (the 3D model of the prostate) was adjusted accordingly and its volume was displayed. The software was implemented on a PC system and was used in the Urology Clinic for several cases. It has been shown that, compared with the value provided by the approximation of the echographic equipment, a more accurate value of the volume of the prostate was obtained.