Reference Case 1 (Pelvis)

Plan a typical treatment using the attached field set-up.   Collimator settings are indicated in addition to field blocking illustrated in the lateral and PA diagrams.   Use a 60 ° (or the wedge most apt to be used) for this set-up and treatment.   The set-up may be isocentric or fixed SSD based on your institution’s treatment technique.  

Implement a weight ratio of 2:1:1 for the posterior and lateral fields respectively. Create two treatment plans with the first photon energy in the range of 4MV-10MV and the second photon energy greater than 10MV, if available.   Please calculate the monitor units or time set to deliver 1.80 Gy at the beam’s intersection.  

Create the plans as if they were actual patients.   Be sure to include the independent monitor set calculation you normally perform.

Calculations:

1.) Radiation Therapy Unit: __________________________________________________________

Treatment distance:      SSD _________ cm;   SAD _________ cm.

Low energy beam: _______ MV;   Wedge Angle ________;   Transmission _________.

High energy beam: _______ MV;   Wedge Angle ________; Transmission _________.   

Does the wedge transmission vary with field size?      YES / NO   (circle one)

Does the wedge transmission vary with depth?      YES / NO   (circle one)

Attach copies of the transmission data

2.) Equation with variables used to calculate required monitor set (mu or min).

Post. monitor set =

Lat. monitor set =

Variables defined:

3.) Please list the actual monitor set used

Post. monitor set =

Left Lat. monitor set =

Right Lat. monitor set =

Pelvis