Every year, a new decayed value must be determined for the c…

Every year, a new decayed value must be determined for the clinical use of cesium-137 tubes. The decay is always calculated from the original assayed value obtained when the source was received. This particular source was received on May 18th, 2017 and upon reception, the activity was 105.3 mCi. You plan to use this source on May 18th, 2021. What will the activity of this source be on the day you plan to use it?

A patient is treated on the 6-MV linear accelerator at 122 c…

A patient is treated on the 6-MV linear accelerator at 122 cm SSD. The collimator setting is 18 x 18 cm and the field size on the patient’s skin is 23 x 23 cm. The prescription calls for a dose of 150 cGy to be administered to a depth of 10 cm with a single anterior field. Calculate the MU setting with the use of PDD.