How is the exact position of the source in the applicator confirmed?

Taking an auto radiograph is a method that allows the precise location of a source within an applicator to be confirmed. This technique involves using a radiographic imaging system to capture an image that clearly shows the position of the radioactive source. Since radiographs can indicate the exact placement and configuration of the source within the treatment device, they provide a reliable visual confirmation.

This approach is critical in ensuring that the source is optimally placed for effective treatment delivery. The need for accuracy is vital in medical dosimetry, as even slight deviations can significantly affect the dose distribution and, consequently, the treatment outcomes.

In contrast, while calibrating with a standard source may ensure that the equipment is functioning correctly, it does not provide specific information about the exact position of the source. Utilizing a surface probe could give information about dose rates but would not directly confirm the positional accuracy of the source itself. Cross-referencing treatment plans is essential for treatment verification but is typically not used as a direct method for confirming the physical position of the source within the applicator.