Overview: 2 Fld vs. 4 Fld Module

This module describes two basic beam arrangements: 2-field (AP/PA) and a 4-field (AP, PA, right lateral, left lateral). When to apply them and the benefits of each arrangement are discussed. In addition, 2-fields vs. 4-fields are illustrated graphically using “real world” patient cases.

At the end of this module, there is a 15 item multiple-choice quiz to gauge your understanding and mastery of 2-field vs. 4-field techniques.

Module Key Words

• 2-field
• AP/PA
• Parallel-opposed
• 4-field
• Rx
• Hot spot
• Weighting