We have reported on standardization of the display of the midcoronal plane of the uterus in 3D volumes in gynecology; this technique, termed the Z technique, should help reduce operator dependency and enhance the diagnostic accuracy of 3D sonography in everyday uses. Details of the Z technique are as follows:
Step 1. Place the reference/rotational point at the midlevel of the endometrial stripe in the sagittal plane (Figure 2).
Step 2. Use Z rotation to align the long axis of the endometrial stripe along the horizontal axis in the sagittal plane of the uterus (Figure 3).
Step 3. Place the reference/rotational point at the midlevel of the endometrial stripe in the transverse plane (Figure 4).
Step 4. Use Z rotation to align the endometrial stripe with the horizontal axis in the transverse plane of the uterus (Figure 5).
Step 5. After step 4, the midcoronal plane of the uterus will be displayed in plane C (Figure 5); apply the Z rotation on plane C to display the midcoronal plane in the traditional orientation (Figure 6).