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Intensity modulated radiation therapy

A doctor prescribes a non-isocentric treatment to a patient’s thoracic spine on a linear accelerator that is calibrated to 100 cm.  The patient is being treated in an AP/PA set up, where the treatment dose is prescribed to the depth of the spine, which is 3.7 cm from the posterior aspect of the patient. The total dose prescribed is 4000 cGy for 10 fractions.  The portal size for the AP is 5 cm x 12 cm and the portal for the PA is 5.3 cm x 11.7 cm. The patient AP/PA separation is 23.1 cm.  What would be the equivalent square for the PA portal when calculating the monitor unit for this portal? 

The subcutaneous layer of the breast contains

Drugs are eliminated from the body through

The time over which a patient’s total dose is delivered is termed as

The tissue surrounding a tumor has a tolerance of 3000 cGy; the tumor has a lethal dose of approximately 3500 cGy. The tumor is considered to be:

A doctor prescribes a non-isocentric treatment to a patient’s thoracic spine on a linear accelerator that is calibrated to 100 cm.  The patient is being treated in an AP/PA set up, where the treatment dose is prescribed to the depth of the spine, which is 3.7 cm from the posterior aspect of the patient. The total dose prescribed is 4000 cGy for 10 fractions.  The portal size for the AP is 5 cm x 12 cm and the portal for the PA is 5.3 cm x 11.7 cm. The patient AP/PA separation is 23.1 cm.  What is the portal size at the prescribed depth for the PA portal? 

You are treating a rectal patient on a Varian 2300 linear accelerator with a calculated SSD of 100 cm.  Your patient’s AP/PA separation is 36 cm and his lateral separations are 42 cm. The tumor is located 19 cm deep from his anterior surface.  The doctor has written a prescription for 28 fractions to a dose of 5040 cGy and a prescription for a boost of 3 fractions to a dose of 540 cGy. The daily monitor units for the AP portal are 58, RT lateral portal 73 and the LT lateral portal 78.  Your patient is beginning his treatment on Thursday 12/1/2019.  Your patient will miss his treatment on 12/9 due to previous obligations. What is your patient’s elapsed day after treatment delivered on 12/6?

Which of the following radiation beam energies will result in more skin sparing?

A patient is being treated for a skin lesion and the order calls for 1 cm of superflab bolus. As the treating therapist, you begin to notice the area you are treating is becoming irritated and moist with each fraction of radiation.  The patient is not complaining of soreness in the affected area, but you feel sorry for your patient. The correct thing to do as the treating therapist is to