Endosonography in obstetrics and gynecology: the importance of standardized image display

The use of endosonographic methods (transvaginal sonography, transrectal sonography, cystosonography, hysterosonography) is increasing for diagnostic and therapeutic procedures in obstetrics and gynecology. Because different means of description lead to confusion, endosonography needs a defined method of orientation. The topography used for transabdominal sonography should also be employed for endosonography. When performing transabdominal sonography, the scanner surface is always projected to the top of the screen, regardless of whether the patient is investigated from a ventral or dorsal position. With endosonography, the contact surface of all linear arrays, curved arrays, and sector scanners should be projected to the bottom of the screen. Using a frontally radiating sector scanner or curved array for a sagittal section, the left side of the screen should correspond with dorsal and the right side with ventral; for all other sections, left and right must be defined. A standardized way of displaying images obtained by endosonography should project the scanner surface to the bottom of the image and can be used on all available technical equipment without major difficulty. The advantage of displaying endosonographic images in this standardized manner is the simple differentiation of pictures obtained by an endosonographic or transabdominal technique.