3D and 4D ultrasound volume ultrasound can obtain image planes and provide depth far beyond the capability of 2D ultrasound. Source: VOLUME SONOGRAPHY: CORE CONCEPTS FOR CLINICAL PRACTICE, Sonography in Obstetrics and Gynecology: Principles & Practice, 7e Citation: Fleischer AC, Toy EC, Lee W, Manning FA, Romero RJ. Sonography in Obstetrics and Gynecology: Principles & Practice, 7e; 2014 Available at: https://obgyn.mhmedical.com/DownloadImage.aspx?image=/data/books/1414/fle_ch43_f002.png&sec=76397129&BookID=1414&ChapterSecID=76397115&imagename= Accessed: October 11, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved