WEDGES

Wedges are used to :

• Reduce hot spots
• Give a more uniform dose distribution

Below is an example of a pair of fields at 90 degree angles and the dose distribution

• Note the hotspot * (dose of 110 %), this would be unacceptable for a treatment plan

Now Wedges will be added to each field with the heels towards each other (to reduce the hotspot and to give a better isodose distribution)

The above diagram is better than the first but still the tumor volume is not within the 90% line.   In this case the isocenter would be shifted so that it will all be included as shown below:

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Below is an example of what would happen if the wedges where placed in the WRONG way: