Before a patient is prescribed any radiation therapy dose, what is the most important thing that must occur before the patient can be considered for treatment?

Which of the following statements best describes radiation treatment depths for a given portal?

The probability for tumor cure and the likelihood for normal tissue damage is termed

The gantry of the linear accelerator  

A patient is being treated isocentrically for cervical cancer. The patient is in the 3rd week of treatment.  The patient is being treated on a machine that is calibrated at 100 SSD.  The tumor is 9.2 cm below the anterior surface of the patient.  The tumor is also located 10.2 cm medial from the patient’s left side. The patient is 26.4 cm thick (AP/PA) and from right to left lateral the patient is 34.6cm.  The doctor prescribes a total dose of 64.8 Gy to be delivered in fractions of 1.8 Gy.  The patient is being treated using a four field box technique. What is the PA SSD?  

Daily quality assurance on the linear accelerator is divided into the following three categories:

In discussing therapeutic ratio, when a tumor can be destroyed but normal tissue suffers severe complications, the tumor is thought to be:

Localizing lasers in the simulation room and the linear accelerator must be within _____________ of the isocenter.

Medical accelerator hazards, which cause the dose to be delivered to the wrong area are caused by all of the following except

Field size