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2 posterior spine fields are required to treat a patient.  They are treated with 6 MV and to a depth of 7 cm.  One field measures 8 x 23 cm at 112 SSD.  Another field measures 8 x 19 cm at 110 SSD.  What is the required gap needed for this treatment?

Which of the following are considered when designing fields and beam arrangements?  (Select all that apply)

Calculate the percentage of the dose attenuated if the measured dose with the wedge is 95 cGy and the dose without the wedge is 125 cGy.

A patient is 24 cm thick.  You are to treat right and left  laterals and give 3600 cGy to midline weighted 2:1 respectively.  the PDD for a depth of 12 cm is .621.  What is the given dose to the left side?

Which of the following represents the relationship between the dose and the PDD at a point?

A patient’s prescription requires a total of 180 cGy to be delivered per day to equally weighted to POP fields (Parallel Opposed Ports).  The treatment time to deliver 100 cGy is 2.15 minutes.  What treatment time must be delivered to each field to follow the prescription?

Which of the following is the ratio of the dose rate of a given field size to the dose rate of the reference field size?

A patient is prescribed 3600 cGy with a total of 15 fractions for an AP/PA lung field weighted 2:1 respectively.  How many cGy does the AP field receive in one fraction?

As depth increases, PDD:

When using a wedge in the radiation beam, the degree of tilt in the iso dose curve is equal to: