What is the PDD for a 10 MV beam at 10 cm depth in a 10x10 cm field?

The percentage depth dose (PDD) for a 10 MV photon beam at a depth of 10 cm in a 10x10 cm field is commonly found to be around 73.0%. This value is important in radiation therapy as it helps dosimetrists determine how much dose is delivered at a certain depth within the tissue compared to the dose at the surface.

The PDD is influenced by several factors, including the energy of the radiation beam and the size of the irradiated field. Higher energy beams, such as 10 MV, have a greater PDD at deeper depths than lower energy beams because they have more penetrating power. At 10 cm depth, the 10 MV beam effectively penetrates the tissue, resulting in a PDD of approximately 73.0%, which reflects the dose that a patient would receive at that depth.

Understanding PDD is essential for accurate dose calculation and patient safety during treatment planning in radiation therapy. The chosen value indicates that a significant portion of the initial dose remains at that depth, showcasing the beam's effectiveness and the impact of the energy and field size on dose distribution.