After the entire thickness was measured by 2D ultrasound, 3 D measurement were taken in the mid-saggittal plan using the multiplanar display mode and then moving through the acquired 3-D volume in the saggittal plane till the thinnest area was seen and then measurements were taken.3-D volume dataset was obtained of the LUS by the same operator. The acquired volume was manipulated on the multiplanar display mode, searching for the thinnest part of the LUS avoiding obliquity.