Three-dimensional ultrasound in gynecology

Abstract

Three-dimensional volume imaging techniques are commonplace in CT and MR imaging; practitioners in these modalities are familiar with the volume or multiplanar environment and recognize their clinical value. More recently in the field of sonography, developments in computer imaging technologies and transducer design have made possible the acquisition of ultrasound volumes that can also be interactively manipulated. With 3D or volume ultrasound (3D US), a volume, rather than a slice, of ultrasound data is acquired and stored. In gynecological applications, 3D US permits any desired plane through a pelvic organ to be obtained. One of the most useful, the coronal so-called face-on plane through the uterus, is routinely obtained with 3D US but rarely seen with 2D US. This view is helpful for assessing uterine contour, allowing precise diagnosis of uterine anomalies. Coronal views of the uterus demonstrate the relationship between the endometrium and myometrium at the uterine fundus, delineate the cervical canal, and depict the cornual angles. Multiple coronal planes facilitate evaluation of the endometrium for focal changes and the endometrial/myometrial junction. Other advantages of 3D US compared to 2D US are: 1) the ability to digitally store ultrasound volume data, which can be retrieved and studied at a later time either on-site or remotely, facilitating consultation and networking; 2) the ability to interact with the volume data and obtain any plane through the uterus, adnexa, and pelvic floor, even after the patient is no longer present; 3) simultaneous correlation of three orthogonal planes in the multiplanar display, along with rendered images; and 4) accurate volume calculations.