Corrective action of the Treatment Planning Systems Eclipse from Varian
2005.03.14
Product group Radiotherapy / Radiation protection
Reference 00219/05
Varian Medical Systems informed about a corrective action of the Treatment Planning Systems Eclipse using Pencil Beam Convolution photon dose calculation algorithm build 7.2.24 or earlier. If for a given field the gantry angle is within 0.1 degrees of 0 or 180 degrees but not exactly 0 or 180 degrees (independent of the treatment unit scale convention used), then the calculated dose distribution for that field is rotated about the field axis by some amount between -90 and +90 degrees from what would be expected.