Optimization of photon beam energy in aperture‐based inverse planning

摘要: Optimal choice of beam energy in radiation therapy is easy many well-documented cases, but less obvious some others. Low-energy beams may provide better conformity around the target than their high-energy counterparts due to reduced lateral scatter, they also contribute overdosage peripheral normal tissue. Beam was added as an optimization parameter automatic aperture-based inverse planning system. We have investigated two sites (prostate and lung), representative deep-seated moderately tumors. For each case different numbers incidences, four plans were optimized: 6 MV, 23 MV, mixed with one or energies per incidence. Each plan scored a dose-volume cost function. Cost function values, number segments, monitor units, parameters isodose distributions compared. prostate lung mixing improved terms more important reduction for small incidences. Use high allows tissue sparing, while keeping similar coverage sensitive structures avoidance. Low contribution units usually increased Thus, tumors, can produce interesting dose low alone.